When writing a lot of small services, testing the interactions between these becomes a major headache. That's the problem Pact is trying to solve.
Integration tests typically are slow and brittle, requiring each component to have its own environment to run the tests in. With a micro-service architecture, this becomes even more of a problem. They also have to be 'all-knowing' and this makes them difficult to keep from being fragile.
After J. B. Rainsberger's talk Integrated Tests Are A Scam people have been thinking how to get the confidence we need to deploy our software to production without having a tiresome integration test suite that does not give us all the coverage we think it does.
PactNet is a .NET implementation of Pact that allows you to define a pact between service consumers and providers. It provides a DSL for service consumers to define the request they will make to a service producer and the response they expect back. This expectation is used in the consumer's specs to provide a mock producer and is also played back in the producer specs to ensure the producer actually does provide the response that the consumer expects.
This allows you to test both sides of an integration point using fast unit tests.
This workshop is aimed at demonstrating core features and benefits of contract testing with Pact.
Whilst contract testing can be applied retrospectively to systems, we will follow the consumer driven contracts approach in this workshop - where a new consumer and provider are created in parallel to evolve a service over time, especially where there is some uncertainty with what is to be built.
This workshop should take from 1 to 2 hours, depending on how deep you want to go into each topic. It's based on the Javascript version of the same workshop
Workshop outline:
- Pact .NET Core Workshop
- Introduction
- Learning objectives
- Prerequisites
- Workshop Steps
- Preamble: Clone repository and explore
- Step 1: Simple consumer calling provider
- Step 2 - Integration problems...
- Step 3 - Pact to the rescue
- Step 4 - Verify the provider
- Step 5 - Back to the client we go
- Step 6 - Consumer updates contract for missing products
- Step 7 - Adding the missing states
- Step 8 - Authorization
- Step 9 - Implement authorization on the provider
- Step 10 - Request Filters on the Provider
If running this as a team workshop format, you may want to take a look through the learning objectives.
This workshop while written with .NET Core is not specifically about it so in-depth knowledge of .NET Core is not required if you can write code in any other language you should be fine.
However before taking part in this workshop please make sure you have:
- .NET Core SDK. Make sure you pick version 6.0 for this.
- An account at github.com!
- A text editor/IDE that supports .NET Core. Check out VSCode
Clone pact-workshop-dotnet-core-v3 and familiarise yourself with its contents. There are two components in scope for our workshop.
- Product client. A command line client that queries the Product service for product information.
- Product Service (Provider). Provides useful things about products, such as listing all products and getting the details of an individual product.
The two components can be found in their respective folders and each have a solution (.sln
) file and project files for the app and test projects (.csproj
)
A consumer project in the Consumer/src folder which is a simple .NET Core console application that connects to the Provider project
A provider in the Provider/src folder and is an ASP.NET Core Web API. Both projects also have a tests/ folder which is where the Pact tests for both projects exist. (Consumer/tests / Consumer/tests)
We need to first create an HTTP client to make the calls to our provider service:
The Consumer has implemented the product service client which has the following:
GET /products
- Retrieve all productsGET /products/{id}
- Retrieve a single product by ID
The diagram below highlights the interaction for retrieving a product with ID 10:
You can see the client interface we created in Consumer/src/ApiClient.cs
:
using System;
using System.Net.Http;
using System.Threading.Tasks;
namespace Consumer
{
public class ApiClient
{
private readonly Uri BaseUri;
public ApiClient(Uri baseUri)
{
this.BaseUri = baseUri;
}
public async Task<HttpResponseMessage> GetAllProducts()
{
using (var client = new HttpClient { BaseAddress = BaseUri })
{
try
{
var response = await client.GetAsync($"/api/products");
return response;
}
catch (Exception ex)
{
throw new Exception("There was a problem connecting to Products API.", ex);
}
}
}
public async Task<HttpResponseMessage> GetProduct(int id)
{
using (var client = new HttpClient { BaseAddress = BaseUri })
{
try
{
var response = await client.GetAsync($"/api/product/{id}");
return response;
}
catch (Exception ex)
{
throw new Exception("There was a problem connecting to Products API.", ex);
}
}
}
}
}
After forking or cloning the repository, we may want to install the dependencies:
cd Consumer\src
dotnet restore
We can run the client with dotnet run
- it should fail with the error below, because the Provider is not running.
our provider team has started building out their API in parallel. Let's run our website against our provider (you'll need two terminals to do this):
###Â Start the Provider
in Provider/src
run dotnet run
❯dotnet run
Hosting environment: Development
Content root path: /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/src
Now listening on: http://localhost:9001
Application started. Press Ctrl+C to shut down.
in Consumer/src
run dotnet run
❯ dotnet run
**Retrieving product list**
Response.Code=OK, Response.Body=[
{
"id": 9,
"name": "GEM Visa",
"type": "CREDIT_CARD",
"version": "v2"
},
{
"id": 10,
"name": "28 Degrees",
"type": "CREDIT_CARD",
"version": "v1"
}
]
**Retrieving product with id=10
Response.Code=NotFound, Response.Body=
So we're able to retrieve a list of products but not a specific product even though one exists with id=10. We're getting a 404 response every time we attempt to access an individual product.
We need to have a conversation about what the endpoint should be!
Unit tests are written and executed in isolation of any other services. When we write tests for code that talk to other services, they are built on trust that the contracts are upheld. There is no way to validate that the consumer and provider can communicate correctly.
An integration contract test is a test at the boundary of an external service verifying that it meets the contract expected by a consuming service — Martin Fowler
Adding contract tests via Pact would have highlighted the /product/{id}
endpoint was incorrect.
Let us add Pact to the project and write a consumer pact test for the GET /product/{id}
endpoint.
Provider states is an important concept of Pact that we need to introduce. These states help define the state that the provider should be in for specific interactions. For the moment, we will initially be testing the following states:
product with ID 10 exists
products exist
The consumer can define the state of an interaction using the given
property.
The file can be found at Consumer/tests/ApiTest.cs
Note how similar it looks to a unit test:
using System.IO;
using PactNet;
using Xunit.Abstractions;
using Xunit;
using System.Net.Http;
using System.Net;
using System.Collections.Generic;
using Newtonsoft.Json;
using Newtonsoft.Json.Serialization;
using Consumer;
using PactNet.Matchers;
using System.Threading.Tasks;
namespace tests
{
public class ApiTest
{
private IPactBuilderV3 pact;
private readonly ApiClient ApiClient;
private readonly int port = 9000;
private readonly List<object> products;
public ApiTest(ITestOutputHelper output)
{
products = new List<object>()
{
new { id = 9, type = "CREDIT_CARD", name = "GEM Visa", version = "v2" },
new { id = 10, type = "CREDIT_CARD", name = "28 Degrees", version = "v1" }
};
var Config = new PactConfig
{
PactDir = Path.Join("..", "..", "..", "..", "..", "pacts"),
Outputters = new[] { new XUnitOutput(output) },
DefaultJsonSettings = new JsonSerializerSettings
{
ContractResolver = new CamelCasePropertyNamesContractResolver()
}
};
pact = Pact.V3("ApiClient", "ProductService", Config).WithHttpInteractions(port);
ApiClient = new ApiClient(new System.Uri($"http://localhost:{port}"));
}
[Fact]
public async Task GetAllProducts()
{
// Arrange
pact.UponReceiving("A valid request for all products")
.Given("products exist")
.WithRequest(HttpMethod.Get, "/api/products")
.WillRespond()
.WithStatus(HttpStatusCode.OK)
.WithHeader("Content-Type", "application/json; charset=utf-8")
.WithJsonBody(new TypeMatcher(products));
await pact.VerifyAsync(async ctx => {
var response = await ApiClient.GetAllProducts();
Assert.Equal(HttpStatusCode.OK, response.StatusCode);
});
}
[Fact]
public async Task GetProduct()
{
// Arrange
pact.UponReceiving("A valid request for a product")
.Given("product with ID 10 exists")
.WithRequest(HttpMethod.Get, "/api/product/10")
.WillRespond()
.WithStatus(HttpStatusCode.OK)
.WithHeader("Content-Type", "application/json; charset=utf-8")
.WithJsonBody(new TypeMatcher(products[1]));
await pact.VerifyAsync(async ctx => {
var response = await ApiClient.GetProduct(10);
Assert.Equal(HttpStatusCode.OK, response.StatusCode);
});
}
}
}
This test starts a mock server on a specificed port (9000 here) that acts as our provider service.
Running this test still passes, but it creates a pact file which we can use to validate our assumptions on the provider side, and have conversation around.
$ ❯ dotnet test
Determining projects to restore...
Restored /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Consumer/tests/tests.csproj (in 317 ms).
1 of 2 projects are up-to-date for restore.
consumer -> /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Consumer/src/bin/Debug/net6.0/consumer.dll
tests -> /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Consumer/tests/bin/Debug/net6.0/tests.dll
Test run for /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Consumer/tests/bin/Debug/net6.0/tests.dll (.NETCoreApp,Version=v6.0)
Microsoft (R) Test Execution Command Line Tool Version 17.3.1 (arm64)
Copyright (c) Microsoft Corporation. All rights reserved.
Starting test execution, please wait...
A total of 1 test files matched the specified pattern.
Passed! - Failed: 0, Passed: 2, Skipped: 0, Total: 2, Duration: 2 ms - /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Consumer/tests/bin/Debug/net6.0/tests.dll (net6.0)
A pact file should have been generated in pacts/ApiClient-ProductService.json
NOTE: even if the API client had been graciously provided for us by our Provider Team, it doesn't mean that we shouldn't write contract tests - because the version of the client we have may not always be in sync with the deployed API - and also because we will write tests on the output appropriate to our specific needs.
Now let's make a start on writing Pact tests to validate the consumer contract:
In provider/tests/ProductTest.cs
:
using System;
using System.Collections.Generic;
using System.IO;
using Microsoft.AspNetCore;
using Microsoft.AspNetCore.Hosting;
using PactNet.Infrastructure.Outputters;
using PactNet.Output.Xunit;
using PactNet.Verifier;
using Xunit;
using Xunit.Abstractions;
namespace tests
{
public class ProductTest
{
private string _pactServiceUri = "http://127.0.0.1:9001";
private readonly ITestOutputHelper _output;
public ProductTest(ITestOutputHelper output)
{
_output = output;
}
[Fact]
public void EnsureProviderApiHonoursPactWithConsumer()
{
// Arrange
var config = new PactVerifierConfig
{
Outputters = new List<IOutput>
{
new XunitOutput(_output)
}
};
using (var _webHost = WebHost.CreateDefaultBuilder().UseStartup<TestStartup>().UseUrls(_pactServiceUri).Build())
{
_webHost.Start();
//Act / Assert
IPactVerifier pactVerifier = new PactVerifier(config);
var pactFile = new FileInfo(Path.Join("..", "..", "..", "..", "..", "pacts", "ApiClient-ProductService.json"));
pactVerifier.ServiceProvider("ProductService", new Uri(_pactServiceUri))
.WithFileSource(pactFile)
.WithProviderStateUrl(new Uri($"{_pactServiceUri}/provider-states"))
.Verify();
}
}
}
}
We now need to validate the pact generated by the consumer is valid, by executing it against the running service provider, which should fail:
Determining projects to restore...
All projects are up-to-date for restore.
provider -> /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/src/bin/Debug/net6.0/provider.dll
tests -> /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/bin/Debug/net6.0/tests.dll
Test run for /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/bin/Debug/net6.0/tests.dll (.NETCoreApp,Version=v6.0)
Microsoft (R) Test Execution Command Line Tool Version 17.3.1 (arm64)
Copyright (c) Microsoft Corporation. All rights reserved.
Starting test execution, please wait...
A total of 1 test files matched the specified pattern.
Verifying a pact between ApiClient and ProductService
A valid request for a product
Given product with ID 10 exists
returns a response which
has status code 200 (FAILED)
includes headers
"Content-Type" with value "application/json; charset=utf-8" (FAILED)
has a matching body (FAILED)
A valid request for all products
Given products exist
returns a response which
has status code 200 (OK)
includes headers
"Content-Type" with value "application/json; charset=utf-8" (OK)
has a matching body (OK)
Failures:
1) Verifying a pact between ApiClient and ProductService Given product with ID 10 exists - A valid request for a product
1.1) has a matching body
/ -> Expected body Present(65 bytes) but was empty
1.2) has status code 200
expected 200 but was 404
1.3) includes header 'Content-Type' with value '"application/json; charset=utf-8"'
Expected header 'Content-Type' to have value '"application/json; charset=utf-8"' but was ''
There were 1 pact failures
[xUnit.net 00:00:01.26] tests.ProductTest.EnsureProviderApiHonoursPactWithConsumer [FAIL]
Failed tests.ProductTest.EnsureProviderApiHonoursPactWithConsumer [824 ms]
Error Message:
PactNet.Exceptions.PactFailureException : Pact verification failed
Stack Trace:
at PactNet.Verifier.InteropVerifierProvider.Execute()
at PactNet.Verifier.PactVerifierSource.Verify()
at tests.ProductTest.EnsureProviderApiHonoursPactWithConsumer() in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/ProductTest.cs:line 43
Standard Output Messages:
Starting verification...
Pact verification failed
Verifier Output
---------------
Verifying a pact between ApiClient and ProductService
A valid request for a product
Given product with ID 10 exists
returns a response which
has status code 200 (FAILED)
includes headers
"Content-Type" with value "application/json; charset=utf-8" (FAILED)
has a matching body (FAILED)
A valid request for all products
Given products exist
returns a response which
has status code 200 (OK)
includes headers
"Content-Type" with value "application/json; charset=utf-8" (OK)
has a matching body (OK)
Failures:
1) Verifying a pact between ApiClient and ProductService Given product with ID 10 exists - A valid request for a product
1.1) has a matching body
/ -> Expected body Present(65 bytes) but was empty
1.2) has status code 200
expected 200 but was 404
1.3) includes header 'Content-Type' with value '"application/json; charset=utf-8"'
Expected header 'Content-Type' to have value '"application/json; charset=utf-8"' but was ''
There were 1 pact failures
Verifier Logs
-------------
2023-04-25T21:07:18.025217Z INFO ThreadId(09) pact_verifier: Running setup provider state change handler 'product with ID 10 exists' for 'A valid request for a product'
2023-04-25T21:07:18.196409Z INFO ThreadId(09) pact_verifier: Running provider verification for 'A valid request for a product'
2023-04-25T21:07:18.197103Z INFO ThreadId(09) pact_verifier::provider_client: Sending request to provider at http://127.0.0.1:9001/
2023-04-25T21:07:18.197104Z INFO ThreadId(09) pact_verifier::provider_client: Sending request HTTP Request ( method: GET, path: /api/product/10, query: None, headers: None, body: Missing )
2023-04-25T21:07:18.208601Z INFO ThreadId(09) pact_verifier::provider_client: Received response: HTTP Response ( status: 404, headers: Some({"content-length": ["0"], "server": ["Kestrel"], "date": ["Tue", "25 Apr 2023 21:07:17 GMT"]}), body: Empty )
2023-04-25T21:07:18.208817Z INFO ThreadId(09) pact_matching: comparing to expected response: HTTP Response ( status: 200, headers: Some({"Content-Type": ["application/json; charset=utf-8"]}), body: Present(65 bytes) )
2023-04-25T21:07:18.360650Z INFO ThreadId(09) pact_verifier: Running setup provider state change handler 'products exist' for 'A valid request for all products'
2023-04-25T21:07:18.509190Z INFO ThreadId(09) pact_verifier: Running provider verification for 'A valid request for all products'
2023-04-25T21:07:18.509220Z INFO ThreadId(09) pact_verifier::provider_client: Sending request to provider at http://127.0.0.1:9001/
2023-04-25T21:07:18.509221Z INFO ThreadId(09) pact_verifier::provider_client: Sending request HTTP Request ( method: GET, path: /api/products, query: None, headers: None, body: Missing )
2023-04-25T21:07:18.520127Z INFO ThreadId(09) pact_verifier::provider_client: Received response: HTTP Response ( status: 200, headers: Some({"date": ["Tue", "25 Apr 2023 21:07:17 GMT"], "server": ["Kestrel"], "content-type": ["application/json; charset=utf-8"], "transfer-encoding": ["chunked"]}), body: Present(191 bytes, application/json;charset=utf-8) )
2023-04-25T21:07:18.520168Z INFO ThreadId(09) pact_matching: comparing to expected response: HTTP Response ( status: 200, headers: Some({"Content-Type": ["application/json; charset=utf-8"]}), body: Present(130 bytes) )
The test has failed, as the expected path /product/{id}
is returning 404. We incorrectly believed our provider was following a RESTful design, but the authors were too lazy to implement a better routing solution 🤷.
The correct endpoint which the consumer should call is /products/{id}
.
We now need to update the consumer client and tests to hit the correct product path.
First, we need to update the GET route for the client:
public async Task<HttpResponseMessage> GetProduct(int id)
{
using (var client = new HttpClient { BaseAddress = BaseUri })
{
try
{
// var response = await client.GetAsync($"/api/products/{id}"); // STEP_4
var response = await client.GetAsync($"/api/product/{id}"); // STEP_5
return response;
}
catch (Exception ex)
{
throw new Exception("There was a problem connecting to Products API.", ex);
}
}
}
Then we need to update the Pact test ID 10 exists
to use the correct endpoint in path
.
[Fact]
public async Task GetProduct()
{
// Arrange
pact.UponReceiving("A valid request for a product")
.Given("product with ID 10 exists")
// .WithRequest(HttpMethod.Get, "/api/product/10") // STEP_4
.WithRequest(HttpMethod.Get, "/api/products/10") // STEP_5
.WillRespond()
.WithStatus(HttpStatusCode.OK)
.WithHeader("Content-Type", "application/json; charset=utf-8")
.WithJsonBody(new TypeMatcher(products[1]));
await pact.VerifyAsync(async ctx => {
var response = await ApiClient.GetProduct(10);
Assert.Equal(HttpStatusCode.OK, response.StatusCode);
});
}
Let's run and generate an updated pact file on the client:
Run this command under Consumer
:
dotnet test
$ dotnet test
Determining projects to restore...
All projects are up-to-date for restore.
consumer -> /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Consumer/src/bin/Debug/net6.0/consumer.dll
tests -> /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Consumer/tests/bin/Debug/net6.0/tests.dll
Test run for /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Consumer/tests/bin/Debug/net6.0/tests.dll (.NETCoreApp,Version=v6.0)
Microsoft (R) Test Execution Command Line Tool Version 17.3.1 (arm64)
Copyright (c) Microsoft Corporation. All rights reserved.
Starting test execution, please wait...
A total of 1 test files matched the specified pattern.
Passed! - Failed: 0, Passed: 2, Skipped: 0, Total: 2, Duration: 8 ms - /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Consumer/tests/bin/Debug/net6.0/tests.dll (net6.0)
Now we run the provider tests again with the updated contract
Run this command under Provider
:
dotnet test
[1] $ dotnet test
Determining projects to restore...
All projects are up-to-date for restore.
provider -> /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/src/bin/Debug/net6.0/provider.dll
tests -> /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/bin/Debug/net6.0/tests.dll
Test run for /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/bin/Debug/net6.0/tests.dll (.NETCoreApp,Version=v6.0)
Microsoft (R) Test Execution Command Line Tool Version 17.3.1 (arm64)
Copyright (c) Microsoft Corporation. All rights reserved.
Starting test execution, please wait...
A total of 1 test files matched the specified pattern.
Verifying a pact between ApiClient and ProductService
A valid request for a product
Given product with ID 10 exists
returns a response which
has status code 200 (OK)
includes headers
"Content-Type" with value "application/json; charset=utf-8" (OK)
has a matching body (OK)
A valid request for all products
Given products exist
returns a response which
has status code 200 (OK)
includes headers
"Content-Type" with value "application/json; charset=utf-8" (OK)
has a matching body (OK)
Passed! - Failed: 0, Passed: 1, Skipped: 0, Total: 1, Duration: < 1 ms - /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/bin/Debug/net6.0/tests.dll (net6.0)
Yay - green âś…!
We're now going to add 2 more scenarios for the contract
- What happens when we make a call for a product that doesn't exist? We assume we'll get a
404
. - What happens when we make a call for getting all products but none exist at the moment? We assume a
200
with an empty array.
Let's write a test for these scenarios, and then generate an updated pact file.
[Fact]
public async Task NoProductsExist()
{
// Arrange
pact.UponReceiving("A valid request for all products")
.Given("no products exist")
.WithRequest(HttpMethod.Get, "/api/products")
.WillRespond()
.WithStatus(HttpStatusCode.OK)
.WithHeader("Content-Type", "application/json; charset=utf-8")
.WithJsonBody(new TypeMatcher(new List<object>()));
await pact.VerifyAsync(async ctx => {
var response = await ApiClient.GetAllProducts();
Assert.Equal(HttpStatusCode.OK, response.StatusCode);
});
}
[Fact]
public async Task ProductDoesNotExist()
{
// Arrange
pact.UponReceiving("A valid request for a product")
.Given("product with ID 11 does not exist")
.WithRequest(HttpMethod.Get, "/api/products/11")
.WillRespond()
.WithStatus(HttpStatusCode.NotFound);
await pact.VerifyAsync(async ctx => {
var response = await ApiClient.GetProduct(11);
Assert.Equal(HttpStatusCode.NotFound, response.StatusCode);
});
}
Notice that our new tests look almost identical to our previous tests, and only differ on the expectations of the response - the HTTP request expectations are exactly the same.
Run this command under Consumer
:
dotnet test
dotnet test
Determining projects to restore...
All projects are up-to-date for restore.
consumer -> /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Consumer/src/bin/Debug/net6.0/consumer.dll
tests -> /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Consumer/tests/bin/Debug/net6.0/tests.dll
Test run for /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Consumer/tests/bin/Debug/net6.0/tests.dll (.NETCoreApp,Version=v6.0)
Microsoft (R) Test Execution Command Line Tool Version 17.3.1 (arm64)
Copyright (c) Microsoft Corporation. All rights reserved.
Starting test execution, please wait...
A total of 1 test files matched the specified pattern.
Passed! - Failed: 0, Passed: 4, Skipped: 0, Total: 4, Duration: 44 ms - /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Consumer/tests/bin/Debug/net6.0/tests.dll (net6.0)
What does our provider have to say about this new test?
Run this command under Provider
:
dotnet test
$ dotnet test
Determining projects to restore...
All projects are up-to-date for restore.
provider -> /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/src/bin/Debug/net6.0/provider.dll
tests -> /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/bin/Debug/net6.0/tests.dll
Test run for /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/bin/Debug/net6.0/tests.dll (.NETCoreApp,Version=v6.0)
Microsoft (R) Test Execution Command Line Tool Version 17.3.1 (arm64)
Copyright (c) Microsoft Corporation. All rights reserved.
Starting test execution, please wait...
A total of 1 test files matched the specified pattern.
fail: Microsoft.AspNetCore.Server.Kestrel[13]
Connection id "0HMQ5QENFP45T", Request id "0HMQ5QENFP45T:00000002": An unhandled exception was thrown by the application.
System.Collections.Generic.KeyNotFoundException: The given key 'no products exist' was not present in the dictionary.
at System.Collections.Generic.Dictionary`2.get_Item(TKey key)
at tests.Middleware.ProviderStateMiddleware.HandleProviderStatesRequest(HttpContext context) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 97
at tests.Middleware.ProviderStateMiddleware.Invoke(HttpContext context) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 70
at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.HttpProtocol.ProcessRequests[TContext](IHttpApplication`1 application)
fail: Microsoft.AspNetCore.Server.Kestrel[13]
Connection id "0HMQ5QENFP45T", Request id "0HMQ5QENFP45T:00000003": An unhandled exception was thrown by the application.
System.Collections.Generic.KeyNotFoundException: The given key 'no products exist' was not present in the dictionary.
at System.Collections.Generic.Dictionary`2.get_Item(TKey key)
at tests.Middleware.ProviderStateMiddleware.HandleProviderStatesRequest(HttpContext context) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 97
at tests.Middleware.ProviderStateMiddleware.Invoke(HttpContext context) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 70
at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.HttpProtocol.ProcessRequests[TContext](IHttpApplication`1 application)
fail: Microsoft.AspNetCore.Server.Kestrel[13]
Connection id "0HMQ5QENFP45T", Request id "0HMQ5QENFP45T:00000004": An unhandled exception was thrown by the application.
System.Collections.Generic.KeyNotFoundException: The given key 'no products exist' was not present in the dictionary.
at System.Collections.Generic.Dictionary`2.get_Item(TKey key)
at tests.Middleware.ProviderStateMiddleware.HandleProviderStatesRequest(HttpContext context) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 97
at tests.Middleware.ProviderStateMiddleware.Invoke(HttpContext context) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 70
at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.HttpProtocol.ProcessRequests[TContext](IHttpApplication`1 application)
fail: Microsoft.AspNetCore.Server.Kestrel[13]
Connection id "0HMQ5QENFP45V", Request id "0HMQ5QENFP45V:00000002": An unhandled exception was thrown by the application.
System.Collections.Generic.KeyNotFoundException: The given key 'product with ID 11 does not exist' was not present in the dictionary.
at System.Collections.Generic.Dictionary`2.get_Item(TKey key)
at tests.Middleware.ProviderStateMiddleware.HandleProviderStatesRequest(HttpContext context) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 97
at tests.Middleware.ProviderStateMiddleware.Invoke(HttpContext context) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 70
at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.HttpProtocol.ProcessRequests[TContext](IHttpApplication`1 application)
fail: Microsoft.AspNetCore.Server.Kestrel[13]
Connection id "0HMQ5QENFP45V", Request id "0HMQ5QENFP45V:00000003": An unhandled exception was thrown by the application.
System.Collections.Generic.KeyNotFoundException: The given key 'product with ID 11 does not exist' was not present in the dictionary.
at System.Collections.Generic.Dictionary`2.get_Item(TKey key)
at tests.Middleware.ProviderStateMiddleware.HandleProviderStatesRequest(HttpContext context) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 97
at tests.Middleware.ProviderStateMiddleware.Invoke(HttpContext context) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 70
at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.HttpProtocol.ProcessRequests[TContext](IHttpApplication`1 application)
fail: Microsoft.AspNetCore.Server.Kestrel[13]
Connection id "0HMQ5QENFP45V", Request id "0HMQ5QENFP45V:00000004": An unhandled exception was thrown by the application.
System.Collections.Generic.KeyNotFoundException: The given key 'product with ID 11 does not exist' was not present in the dictionary.
at System.Collections.Generic.Dictionary`2.get_Item(TKey key)
at tests.Middleware.ProviderStateMiddleware.HandleProviderStatesRequest(HttpContext context) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 97
at tests.Middleware.ProviderStateMiddleware.Invoke(HttpContext context) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 70
at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.HttpProtocol.ProcessRequests[TContext](IHttpApplication`1 application)
Verifying a pact between ApiClient and ProductService
A valid request for all products
Given no products exist
Request Failed - One or more of the setup state change handlers has failed
A valid request for a product
Given product with ID 10 exists
returns a response which
has status code 200 (OK)
includes headers
"Content-Type" with value "application/json; charset=utf-8" (OK)
has a matching body (OK)
A valid request for a product
Given product with ID 11 does not exist
Request Failed - One or more of the setup state change handlers has failed
A valid request for all products
Given products exist
returns a response which
has status code 200 (OK)
includes headers
"Content-Type" with value "application/json; charset=utf-8" (OK)
has a matching body (OK)
Failures:
1) Verifying a pact between ApiClient and ProductService Given no products exist - A valid request for all products - One or more of the setup state change handlers has failed
2) Verifying a pact between ApiClient and ProductService Given product with ID 11 does not exist - A valid request for a product - One or more of the setup state change handlers has failed
There were 2 pact failures
[xUnit.net 00:00:04.07] tests.ProductTest.EnsureProviderApiHonoursPactWithConsumer [FAIL]
Failed tests.ProductTest.EnsureProviderApiHonoursPactWithConsumer [3 s]
Error Message:
PactNet.Exceptions.PactFailureException : Pact verification failed
Stack Trace:
at PactNet.Verifier.InteropVerifierProvider.Execute()
at PactNet.Verifier.PactVerifierSource.Verify()
at tests.ProductTest.EnsureProviderApiHonoursPactWithConsumer() in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/ProductTest.cs:line 43
Standard Output Messages:
Starting verification...
Pact verification failed
Verifier Logs
-------------
2023-04-25T21:26:07.762714Z INFO ThreadId(09) pact_verifier: Running setup provider state change handler 'no products exist' for 'A valid request for all products'
2023-04-25T21:26:09.055377Z ERROR ThreadId(09) pact_verifier: Provider setup state change for 'no products exist' has failed - MismatchResult::Error("Invalid status code: 500", None)
2023-04-25T21:26:09.222861Z INFO ThreadId(09) pact_verifier: Running setup provider state change handler 'product with ID 10 exists' for 'A valid request for a product'
2023-04-25T21:26:09.378031Z INFO ThreadId(09) pact_verifier: Running provider verification for 'A valid request for a product'
2023-04-25T21:26:09.379094Z INFO ThreadId(09) pact_verifier::provider_client: Sending request to provider at http://127.0.0.1:9001/
2023-04-25T21:26:09.379097Z INFO ThreadId(09) pact_verifier::provider_client: Sending request HTTP Request ( method: GET, path: /api/products/10, query: None, headers: None, body: Missing )
2023-04-25T21:26:09.404093Z INFO ThreadId(09) pact_verifier::provider_client: Received response: HTTP Response ( status: 200, headers: Some({"date": ["Tue", "25 Apr 2023 21:26:08 GMT"], "server": ["Kestrel"], "transfer-encoding": ["chunked"], "content-type": ["application/json; charset=utf-8"]}), body: Present(82 bytes, application/json;charset=utf-8) )
2023-04-25T21:26:09.404145Z INFO ThreadId(09) pact_matching: comparing to expected response: HTTP Response ( status: 200, headers: Some({"Content-Type": ["application/json; charset=utf-8"]}), body: Present(65 bytes) )
2023-04-25T21:26:09.554354Z INFO ThreadId(09) pact_verifier: Running setup provider state change handler 'product with ID 11 does not exist' for 'A valid request for a product'
2023-04-25T21:26:10.805314Z ERROR ThreadId(09) pact_verifier: Provider setup state change for 'product with ID 11 does not exist' has failed - MismatchResult::Error("Invalid status code: 500", None)
2023-04-25T21:26:10.961930Z INFO ThreadId(09) pact_verifier: Running setup provider state change handler 'products exist' for 'A valid request for all products'
2023-04-25T21:26:11.104594Z INFO ThreadId(09) pact_verifier: Running provider verification for 'A valid request for all products'
2023-04-25T21:26:11.104626Z INFO ThreadId(09) pact_verifier::provider_client: Sending request to provider at http://127.0.0.1:9001/
2023-04-25T21:26:11.104628Z INFO ThreadId(09) pact_verifier::provider_client: Sending request HTTP Request ( method: GET, path: /api/products, query: None, headers: None, body: Missing )
2023-04-25T21:26:11.106257Z INFO ThreadId(09) pact_verifier::provider_client: Received response: HTTP Response ( status: 200, headers: Some({"content-type": ["application/json; charset=utf-8"], "date": ["Tue", "25 Apr 2023 21:26:10 GMT"], "transfer-encoding": ["chunked"], "server": ["Kestrel"]}), body: Present(191 bytes, application/json;charset=utf-8) )
2023-04-25T21:26:11.106274Z INFO ThreadId(09) pact_matching: comparing to expected response: HTTP Response ( status: 200, headers: Some({"Content-Type": ["application/json; charset=utf-8"]}), body: Present(130 bytes) )
We got two failures related to provider state:
fail: Microsoft.AspNetCore.Server.Kestrel[13]
Connection id "0HMB3KDP4M8GV", Request id "0HMB3KDP4M8GV:00000002": An unhandled exception was thrown by the application.
System.Collections.Generic.KeyNotFoundException: The given key 'no products exist' was not present in the dictionary.
at System.Collections.Generic.Dictionary`2.get_Item(TKey key)
at tests.Middleware.ProviderStateMiddleware.HandleProviderStatesRequest(HttpContext context) in /Users/erikdanielsen/work/dius/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 84
at tests.Middleware.ProviderStateMiddleware.Invoke(HttpContext context) in /Users/erikdanielsen/work/dius/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 57
at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.HttpProtocol.ProcessRequests[TContext](IHttpApplication`1 application)
fail: Microsoft.AspNetCore.Server.Kestrel[13]
Connection id "0HMB3KDP4M8H0", Request id "0HMB3KDP4M8H0:00000002": An unhandled exception was thrown by the application.
System.Collections.Generic.KeyNotFoundException: The given key 'product does not exist' was not present in the dictionary.
at System.Collections.Generic.Dictionary`2.get_Item(TKey key)
at tests.Middleware.ProviderStateMiddleware.HandleProviderStatesRequest(HttpContext context) in /Users/erikdanielsen/work/dius/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 84
at tests.Middleware.ProviderStateMiddleware.Invoke(HttpContext context) in /Users/erikdanielsen/work/dius/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 57
at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.HttpProtocol.ProcessRequests[TContext](IHttpApplication`1 application)
We can solve this by making sure we handle the missing provider states, which also helps us understand how Provider states work more generally.
Our code already deals with missing products and sends a 404
response, however our test data fixture always has product ID 9 and 10 in our database.
In this step, we will add a state handler to our provider Pact verifications, which will update the state of our data store depending on which states the consumers require.
States are invoked prior to the actual test function is invoked. You can see the full lifecycle here.
We're going to add handlers for all our states:
- products exist
- no products exist
- product with ID 10 exists
- product with ID 11 does not exist
Let's open up our provider Pact verifications in Provider/tests/Middleware/ProviderStateMiddleware.cs
:
// update the dictionary defined in the constructor
_providerStates = new Dictionary<string, Action>
{
{ "products exist", ProductsExist },
{ "product with ID 10 exists", Product10Exists },
{ "product with ID 11 does not exist", Product11DoesNotExist }, // STEP_7
{ "no products exist", NoProductsExist }, // STEP_7
// { "No auth token is provided", Product10Exists } // STEP_10
};
Also implement handlers for the two new states:
private void NoProductsExist()
{
_repository.SetState(new List<Product>());
}
private void Product11DoesNotExist()
{
ProductsExist();
}
In NoProductsExist()
we set the current state to an empty list. For Product11DoesNotExist()
we can just use one of the existing states since product 11 does not exist.
Let's see how we go now:
Run this command under Provider
:
dotnet test
$ dotnet test
Determining projects to restore...
All projects are up-to-date for restore.
provider -> /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/src/bin/Debug/net6.0/provider.dll
tests -> /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/bin/Debug/net6.0/tests.dll
Test run for /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/bin/Debug/net6.0/tests.dll (.NETCoreApp,Version=v6.0)
Microsoft (R) Test Execution Command Line Tool Version 17.3.1 (arm64)
Copyright (c) Microsoft Corporation. All rights reserved.
Starting test execution, please wait...
A total of 1 test files matched the specified pattern.
Verifying a pact between ApiClient and ProductService
A valid request for all products
Given no products exist
returns a response which
has status code 200 (OK)
includes headers
"Content-Type" with value "application/json; charset=utf-8" (OK)
has a matching body (OK)
A valid request for a product
Given product with ID 10 exists
returns a response which
has status code 200 (OK)
includes headers
"Content-Type" with value "application/json; charset=utf-8" (OK)
has a matching body (OK)
A valid request for a product
Given product with ID 11 does not exist
returns a response which
has status code 404 (OK)
has a matching body (OK)
A valid request for all products
Given products exist
returns a response which
has status code 200 (OK)
includes headers
"Content-Type" with value "application/json; charset=utf-8" (OK)
has a matching body (OK)
Passed! - Failed: 0, Passed: 1, Skipped: 0, Total: 1, Duration: < 1 ms - /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/bin/Debug/net6.0/tests.dll (net6.0)
NOTE: The states are not necessarily a 1 to 1 mapping with the consumer contract tests. You can reuse states amongst different tests. In this scenario we could have used no products exist
for both tests which would have equally been valid.
It turns out that not everyone should be able to use the API. After a discussion with the team, it was decided that a time-bound bearer token would suffice. The token must be in yyyy-MM-ddTHHmm
format and within 1 hour of the current time.
In the case a valid bearer token is not provided, we expect a 401
. Let's first update the consumer tests and add scenarios for expected the Authorization
header. In Consumer/tests/ApiTest.cs
:
[Fact]
public async Task GetAllProducts()
{
// Arrange
pact.UponReceiving("A valid request for all products")
.Given("products exist")
.WithRequest(HttpMethod.Get, "/api/products")
.WithHeader("Authorization", Match.Regex("Bearer 2019-01-14T11:34:18.045Z", "Bearer \\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d{3}Z")) // STEP_8
.WillRespond()
.WithStatus(HttpStatusCode.OK)
.WithHeader("Content-Type", "application/json; charset=utf-8")
.WithJsonBody(new TypeMatcher(products));
await pact.VerifyAsync(async ctx => {
var response = await ApiClient.GetAllProducts();
Assert.Equal(HttpStatusCode.OK, response.StatusCode);
});
}
[Fact]
public async Task GetProduct()
{
// Arrange
pact.UponReceiving("A valid request for a product")
.Given("product with ID 10 exists")
// .WithRequest(HttpMethod.Get, "/api/product/10") // STEP_4
.WithRequest(HttpMethod.Get, "/api/products/10") // STEP_5
.WithHeader("Authorization", Match.Regex("Bearer 2019-01-14T11:34:18.045Z", "Bearer \\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d{3}Z")) // STEP_8
.WillRespond()
.WithStatus(HttpStatusCode.OK)
.WithHeader("Content-Type", "application/json; charset=utf-8")
.WithJsonBody(new TypeMatcher(products[1]));
await pact.VerifyAsync(async ctx => {
var response = await ApiClient.GetProduct(10);
Assert.Equal(HttpStatusCode.OK, response.StatusCode);
});
}
// STEP_6
[Fact]
public async Task NoProductsExist()
{
// Arrange
pact.UponReceiving("A valid request for all products")
.Given("no products exist")
.WithRequest(HttpMethod.Get, "/api/products")
.WithHeader("Authorization", Match.Regex("Bearer 2019-01-14T11:34:18.045Z", "Bearer \\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d{3}Z")) // STEP_8
.WillRespond()
.WithStatus(HttpStatusCode.OK)
.WithHeader("Content-Type", "application/json; charset=utf-8")
.WithJsonBody(new TypeMatcher(new List<object>()));
await pact.VerifyAsync(async ctx => {
var response = await ApiClient.GetAllProducts();
Assert.Equal(HttpStatusCode.OK, response.StatusCode);
});
}
// STEP_6
[Fact]
public async Task ProductDoesNotExist()
{
// Arrange
pact.UponReceiving("A valid request for a product")
.Given("product with ID 11 does not exist")
.WithRequest(HttpMethod.Get, "/api/products/11")
.WithHeader("Authorization", Match.Regex("Bearer 2019-01-14T11:34:18.045Z", "Bearer \\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d{3}Z")) // STEP_8
.WillRespond()
.WithStatus(HttpStatusCode.NotFound);
await pact.VerifyAsync(async ctx => {
var response = await ApiClient.GetProduct(11);
Assert.Equal(HttpStatusCode.NotFound, response.StatusCode);
});
}
// STEP_8
[Fact]
public async Task GetProductMissingAuthHeader()
{
// Arrange
pact.UponReceiving("A valid request for a product")
.Given("No auth token is provided")
.WithRequest(HttpMethod.Get, "/api/products/10")
.WillRespond()
.WithStatus(HttpStatusCode.Unauthorized);
await pact.VerifyAsync(async ctx => {
var response = await ApiClient.GetProduct(10);
Assert.Equal(HttpStatusCode.Unauthorized, response.StatusCode);
});
}
We could implement the header as well but let's first briefly explain what's going on here. Instead of simply entering a header we use a matcher
. A matcher
can be used when we don't necessarily need to test exact values but e.g. just check the type, or the pattern. In the example above we use a Regex
matcher.
We provide an example value (which will end up in the pact file) as well as the pattern we want the value to match. This means that we can dynamically generate
the value and still have a passing test.
Before we implement the change, let's see what happens if we run it without implementing. The output is very long so it's been abbreviated to show the only one the four test cases:
[1] $ dotnet test
Determining projects to restore...
All projects are up-to-date for restore.
consumer -> /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Consumer/src/bin/Debug/net6.0/consumer.dll
tests -> /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Consumer/tests/bin/Debug/net6.0/tests.dll
Test run for /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Consumer/tests/bin/Debug/net6.0/tests.dll (.NETCoreApp,Version=v6.0)
Microsoft (R) Test Execution Command Line Tool Version 17.3.1 (arm64)
Copyright (c) Microsoft Corporation. All rights reserved.
Starting test execution, please wait...
A total of 1 test files matched the specified pattern.
[xUnit.net 00:00:00.41] tests.ApiTest.GetAllProducts [FAIL]
[xUnit.net 00:00:00.42] tests.ApiTest.GetProduct [FAIL]
Failed tests.ApiTest.GetAllProducts [43 ms]
Error Message:
Assert.Equal() Failure
Expected: OK
Actual: InternalServerError
Stack Trace:
at tests.ApiTest.<GetAllProducts>b__5_0(IConsumerContext ctx) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Consumer/tests/ApiTest.cs:line 61
at PactNet.PactBuilder.VerifyAsync(Func`2 interact)
at tests.ApiTest.GetAllProducts() in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Consumer/tests/ApiTest.cs:line 59
--- End of stack trace from previous location ---
Standard Output Messages:
Mock driver logs:
2023-04-25T21:42:47.302759Z INFO tokio-runtime-worker pact_mock_server::hyper_server: Received request HTTP Request ( method: GET, path: /api/products, query: None, headers: Some({"host": ["localhost:9000"]}), body: Empty )
2023-04-25T21:42:47.302792Z INFO tokio-runtime-worker pact_matching: comparing to expected HTTP Request ( method: GET, path: /api/products, query: None, headers: Some({"Authorization": ["Bearer 2019-01-14T11:34:18.045Z"]}), body: Missing )
Failed tests.ApiTest.GetProduct [2 ms]
Error Message:
Assert.Equal() Failure
Expected: OK
Actual: InternalServerError
Stack Trace:
at tests.ApiTest.<GetProduct>b__6_0(IConsumerContext ctx) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Consumer/tests/ApiTest.cs:line 81
at PactNet.PactBuilder.VerifyAsync(Func`2 interact)
at tests.ApiTest.GetProduct() in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Consumer/tests/ApiTest.cs:line 79
--- End of stack trace from previous location ---
Standard Output Messages:
Mock driver logs:
2023-04-25T21:42:47.310701Z INFO tokio-runtime-worker pact_mock_server::hyper_server: Received request HTTP Request ( method: GET, path: /api/products/10, query: None, headers: Some({"host": ["localhost:9000"]}), body: Empty )
2023-04-25T21:42:47.310721Z INFO tokio-runtime-worker pact_matching: comparing to expected HTTP Request ( method: GET, path: /api/products/10, query: None, headers: Some({"Authorization": ["Bearer 2019-01-14T11:34:18.045Z"]}), body: Missing )
The standard logs, don't always give us enough information in case of failure, you can enable debug logging in Consumer/tests/ApiTest.cs
:
var Config = new PactConfig
{
PactDir = Path.Join("..", "..", "..", "..", "..", "pacts"),
Outputters = new[] { new XUnitOutput(output) },
DefaultJsonSettings = new JsonSerializerSettings
{
ContractResolver = new CamelCasePropertyNamesContractResolver()
},
LogLevel = PactLogLevel.Debug // STEP_8
};
and run your test again, The key information can be found in the DEBUG
output:
2023-04-25T21:44:17.273570Z DEBUG tokio-runtime-worker pact_matching: --> Mismatches: [HeaderMismatch { key: "Authorization", expected: "\"Bearer 2019-01-14T11:34:18.045Z\"", actual: "", mismatch: "Expected header 'Authorization' but was missing" }]
2023-04-25T21:44:17.273591Z DEBUG tokio-runtime-worker pact_mock_server::hyper_server: Request did not match: Request did not match - HTTP Request ( method: GET, path: /api/products/10, query: None, headers: Some({"Authorization": ["Bearer 2019-01-14T11:34:18.045Z"]}), body: Missing ) 0) Expected header 'Authorization' but was missing
Let's update the consumer to pass the bearer token, which was missing
public async Task<HttpResponseMessage> GetAllProducts()
{
using (var client = new HttpClient { BaseAddress = BaseUri })
{
try
{
client.DefaultRequestHeaders.Add("Authorization", AuthorizationHeaderValue()); // STEP_8
var response = await client.GetAsync($"/api/products");
return response;
}
catch (Exception ex)
{
throw new Exception("There was a problem connecting to Products API.", ex);
}
}
}
public async Task<HttpResponseMessage> GetProduct(int id)
{
using (var client = new HttpClient { BaseAddress = BaseUri })
{
try
{
client.DefaultRequestHeaders.Add("Authorization", AuthorizationHeaderValue()); // STEP_8
var response = await client.GetAsync($"/api/products/{id}");
// var response = await client.GetAsync($"/api/product/{id}"); // STEP_5
return response;
}
catch (Exception ex)
{
throw new Exception("There was a problem connecting to Products API.", ex);
}
}
}
// STEP_8
private string AuthorizationHeaderValue()
{
return $"Bearer {DateTime.Now.ToString("yyyy-MM-ddTHH:mm:ss.fffZ")}";
}
Generate a new Pact file:
$ dotnet test
Determining projects to restore...
All projects are up-to-date for restore.
consumer -> /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Consumer/src/bin/Debug/net6.0/consumer.dll
tests -> /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Consumer/tests/bin/Debug/net6.0/tests.dll
Test run for /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Consumer/tests/bin/Debug/net6.0/tests.dll (.NETCoreApp,Version=v6.0)
Microsoft (R) Test Execution Command Line Tool Version 17.3.1 (arm64)
Copyright (c) Microsoft Corporation. All rights reserved.
Starting test execution, please wait...
A total of 1 test files matched the specified pattern.
Passed! - Failed: 0, Passed: 5, Skipped: 0, Total: 5, Duration: 55 ms - /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Consumer/tests/bin/Debug/net6.0/tests.dll (net6.0
The changes in the pact file located at pacts/ApiClient-ProductService.json
is now that we have some logic for header matching:
"request": {
"headers": {
"Authorization": "Bearer 2019-01-14T11:34:18.045Z"
},
"matchingRules": {
"header": {
"$.Authorization[0]": {
"combine": "AND",
"matchers": [
{
"match": "regex",
"regex": "Bearer \\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d{3}Z"
}
]
}
}
},
"method": "GET",
"path": "/api/products"
},
Let's test the provider.
Run this command under Provider
:
dotnet test
[1] $ dotnet test
Determining projects to restore...
All projects are up-to-date for restore.
provider -> /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/src/bin/Debug/net6.0/provider.dll
tests -> /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/bin/Debug/net6.0/tests.dll
Test run for /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/bin/Debug/net6.0/tests.dll (.NETCoreApp,Version=v6.0)
Microsoft (R) Test Execution Command Line Tool Version 17.3.1 (arm64)
Copyright (c) Microsoft Corporation. All rights reserved.
Starting test execution, please wait...
A total of 1 test files matched the specified pattern.
fail: Microsoft.AspNetCore.Server.Kestrel[13]
Connection id "0HMQ5QRJDM11B", Request id "0HMQ5QRJDM11B:00000002": An unhandled exception was thrown by the application.
System.Collections.Generic.KeyNotFoundException: The given key 'No auth token is provided' was not present in the dictionary.
at System.Collections.Generic.Dictionary`2.get_Item(TKey key)
at tests.Middleware.ProviderStateMiddleware.HandleProviderStatesRequest(HttpContext context) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 99
at tests.Middleware.ProviderStateMiddleware.Invoke(HttpContext context) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 72
at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.HttpProtocol.ProcessRequests[TContext](IHttpApplication`1 application)
fail: Microsoft.AspNetCore.Server.Kestrel[13]
Connection id "0HMQ5QRJDM11B", Request id "0HMQ5QRJDM11B:00000003": An unhandled exception was thrown by the application.
System.Collections.Generic.KeyNotFoundException: The given key 'No auth token is provided' was not present in the dictionary.
at System.Collections.Generic.Dictionary`2.get_Item(TKey key)
at tests.Middleware.ProviderStateMiddleware.HandleProviderStatesRequest(HttpContext context) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 99
at tests.Middleware.ProviderStateMiddleware.Invoke(HttpContext context) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 72
at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.HttpProtocol.ProcessRequests[TContext](IHttpApplication`1 application)
fail: Microsoft.AspNetCore.Server.Kestrel[13]
Connection id "0HMQ5QRJDM11B", Request id "0HMQ5QRJDM11B:00000004": An unhandled exception was thrown by the application.
System.Collections.Generic.KeyNotFoundException: The given key 'No auth token is provided' was not present in the dictionary.
at System.Collections.Generic.Dictionary`2.get_Item(TKey key)
at tests.Middleware.ProviderStateMiddleware.HandleProviderStatesRequest(HttpContext context) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 99
at tests.Middleware.ProviderStateMiddleware.Invoke(HttpContext context) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 72
at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.HttpProtocol.ProcessRequests[TContext](IHttpApplication`1 application)
Verifying a pact between ApiClient and ProductService
A valid request for a product
Given No auth token is provided
Request Failed - One or more of the setup state change handlers has failed
A valid request for all products
Given no products exist
returns a response which
has status code 200 (OK)
includes headers
"Content-Type" with value "application/json; charset=utf-8" (OK)
has a matching body (OK)
A valid request for a product
Given product with ID 10 exists
returns a response which
has status code 200 (OK)
includes headers
"Content-Type" with value "application/json; charset=utf-8" (OK)
has a matching body (OK)
A valid request for a product
Given product with ID 11 does not exist
returns a response which
has status code 404 (OK)
has a matching body (OK)
A valid request for all products
Given products exist
returns a response which
has status code 200 (OK)
includes headers
"Content-Type" with value "application/json; charset=utf-8" (OK)
has a matching body (OK)
Failures:
1) Verifying a pact between ApiClient and ProductService Given No auth token is provided - A valid request for a product - One or more of the setup state change handlers has failed
There were 1 pact failures
[xUnit.net 00:00:03.31] tests.ProductTest.EnsureProviderApiHonoursPactWithConsumer [FAIL]
Failed tests.ProductTest.EnsureProviderApiHonoursPactWithConsumer [2 s]
Error Message:
PactNet.Exceptions.PactFailureException : Pact verification failed
Stack Trace:
at PactNet.Verifier.InteropVerifierProvider.Execute()
at PactNet.Verifier.PactVerifierSource.Verify()
at tests.ProductTest.EnsureProviderApiHonoursPactWithConsumer() in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/ProductTest.cs:line 43
Standard Output Messages:
Starting verification...
Pact verification failed
Verifier Logs
-------------
2023-04-25T21:49:09.979495Z INFO ThreadId(09) pact_verifier: Running setup provider state change handler 'No auth token is provided' for 'A valid request for a product'
2023-04-25T21:49:11.277542Z ERROR ThreadId(09) pact_verifier: Provider setup state change for 'No auth token is provided' has failed - MismatchResult::Error("Invalid status code: 500", None)
2023-04-25T21:49:11.450384Z INFO ThreadId(09) pact_verifier: Running setup provider state change handler 'no products exist' for 'A valid request for all products'
2023-04-25T21:49:11.594683Z INFO ThreadId(09) pact_verifier: Running provider verification for 'A valid request for all products'
2023-04-25T21:49:11.595974Z INFO ThreadId(09) pact_verifier::provider_client: Sending request to provider at http://127.0.0.1:9001/
2023-04-25T21:49:11.595977Z INFO ThreadId(09) pact_verifier::provider_client: Sending request HTTP Request ( method: GET, path: /api/products, query: None, headers: None, body: Missing )
2023-04-25T21:49:11.612998Z INFO ThreadId(09) pact_verifier::provider_client: Received response: HTTP Response ( status: 200, headers: Some({"date": ["Tue", "25 Apr 2023 21:49:10 GMT"], "server": ["Kestrel"], "content-type": ["application/json; charset=utf-8"], "transfer-encoding": ["chunked"]}), body: Present(2 bytes, application/json;charset=utf-8) )
2023-04-25T21:49:11.613047Z INFO ThreadId(09) pact_matching: comparing to expected response: HTTP Response ( status: 200, headers: Some({"Content-Type": ["application/json; charset=utf-8"]}), body: Present(2 bytes) )
2023-04-25T21:49:11.768563Z INFO ThreadId(09) pact_verifier: Running setup provider state change handler 'product with ID 10 exists' for 'A valid request for a product'
2023-04-25T21:49:11.913473Z INFO ThreadId(09) pact_verifier: Running provider verification for 'A valid request for a product'
2023-04-25T21:49:11.913512Z INFO ThreadId(09) pact_verifier::provider_client: Sending request to provider at http://127.0.0.1:9001/
2023-04-25T21:49:11.913513Z INFO ThreadId(09) pact_verifier::provider_client: Sending request HTTP Request ( method: GET, path: /api/products/10, query: None, headers: Some({"Authorization": ["Bearer 2019-01-14T11:34:18.045Z"]}), body: Missing )
2023-04-25T21:49:11.921699Z INFO ThreadId(09) pact_verifier::provider_client: Received response: HTTP Response ( status: 200, headers: Some({"date": ["Tue", "25 Apr 2023 21:49:11 GMT"], "transfer-encoding": ["chunked"], "server": ["Kestrel"], "content-type": ["application/json; charset=utf-8"]}), body: Present(82 bytes, application/json;charset=utf-8) )
2023-04-25T21:49:11.921718Z INFO ThreadId(09) pact_matching: comparing to expected response: HTTP Response ( status: 200, headers: Some({"Content-Type": ["application/json; charset=utf-8"]}), body: Present(65 bytes) )
2023-04-25T21:49:12.066023Z INFO ThreadId(09) pact_verifier: Running setup provider state change handler 'product with ID 11 does not exist' for 'A valid request for a product'
2023-04-25T21:49:12.218216Z INFO ThreadId(09) pact_verifier: Running provider verification for 'A valid request for a product'
2023-04-25T21:49:12.218250Z INFO ThreadId(09) pact_verifier::provider_client: Sending request to provider at http://127.0.0.1:9001/
2023-04-25T21:49:12.218251Z INFO ThreadId(09) pact_verifier::provider_client: Sending request HTTP Request ( method: GET, path: /api/products/11, query: None, headers: None, body: Missing )
2023-04-25T21:49:12.219873Z INFO ThreadId(09) pact_verifier::provider_client: Received response: HTTP Response ( status: 404, headers: Some({"date": ["Tue", "25 Apr 2023 21:49:11 GMT"], "content-length": ["0"], "server": ["Kestrel"]}), body: Empty )
2023-04-25T21:49:12.219880Z INFO ThreadId(09) pact_matching: comparing to expected response: HTTP Response ( status: 404, headers: None, body: Missing )
2023-04-25T21:49:12.374008Z INFO ThreadId(09) pact_verifier: Running setup provider state change handler 'products exist' for 'A valid request for all products'
2023-04-25T21:49:12.524133Z INFO ThreadId(09) pact_verifier: Running provider verification for 'A valid request for all products'
2023-04-25T21:49:12.524173Z INFO ThreadId(09) pact_verifier::provider_client: Sending request to provider at http://127.0.0.1:9001/
2023-04-25T21:49:12.524174Z INFO ThreadId(09) pact_verifier::provider_client: Sending request HTTP Request ( method: GET, path: /api/products, query: None, headers: Some({"Authorization": ["Bearer 2019-01-14T11:34:18.045Z"]}), body: Missing )
2023-04-25T21:49:12.524756Z INFO ThreadId(09) pact_verifier::provider_client: Received response: HTTP Response ( status: 200, headers: Some({"content-type": ["application/json; charset=utf-8"], "date": ["Tue", "25 Apr 2023 21:49:11 GMT"], "server": ["Kestrel"], "transfer-encoding": ["chunked"]}), body: Present(191 bytes, application/json;charset=utf-8) )
2023-04-25T21:49:12.524769Z INFO ThreadId(09) pact_matching: comparing to expected response: HTTP Response ( status: 200, headers: Some({"Content-Type": ["application/json; charset=utf-8"]}), body: Present(130 bytes) )
Now with the most recently added interactions where we are expecting a response of 401 when no authorization header is sent, we are getting 200...
We will add a middleware to check the Authorization header and deny the request with 401
if the token is older than 1 hour.
In the folder called Provider/src/Middleware
, we are going to create a class called AuthorizationMiddleware.cs
:
using System;
using System.Text.RegularExpressions;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Http;
namespace provider.Middleware
{
public class AuthorizationMiddleware
{
private const string AuthorizationHeaderKey = "Authorization";
private readonly RequestDelegate _next;
public AuthorizationMiddleware(RequestDelegate next)
{
_next = next;
}
public async Task Invoke(HttpContext context)
{
if (context.Request.Headers.ContainsKey(AuthorizationHeaderKey))
{
DateTime tokenTime = DateTime.Parse(AuthorizationHeader(context.Request));
if (IsOlderThanOneHour(tokenTime))
{
UnauthorizedResponse(context);
}
else
{
await this._next(context);
}
}
else
{
UnauthorizedResponse(context);
}
}
private string AuthorizationHeader(HttpRequest request)
{
request.Headers.TryGetValue(AuthorizationHeaderKey, out var authorizationHeader);
var match = Regex.Match(authorizationHeader, "Bearer (.*)");
return match.Groups[1].Value;
}
private bool IsOlderThanOneHour(DateTime tokenTime)
{
return tokenTime < DateTime.Now.AddHours(-1);
}
private void UnauthorizedResponse(HttpContext context)
{
context.Response.StatusCode = StatusCodes.Status401Unauthorized;
}
}
}
Add the middleware in Provider/src/Startup.cs
, including the using
statement:
using provider.Middleware; // STEP_9
...
// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
app.UseMiddleware<AuthorizationMiddleware>(); // STEP_9
app.UseRouting();
app.UseEndpoints(e => e.MapControllers());
}
This means that a client must present an HTTP Authorization
header that looks as follows:
Authorization: Bearer 2006-01-02T15:04
Let's test this out:
Run this command under Provider
:
dotnet test
[1] $ dotnet test
Determining projects to restore...
All projects are up-to-date for restore.
provider -> /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/src/bin/Debug/net6.0/provider.dll
tests -> /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/bin/Debug/net6.0/tests.dll
Test run for /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/bin/Debug/net6.0/tests.dll (.NETCoreApp,Version=v6.0)
Microsoft (R) Test Execution Command Line Tool Version 17.3.1 (arm64)
Copyright (c) Microsoft Corporation. All rights reserved.
Starting test execution, please wait...
A total of 1 test files matched the specified pattern.
fail: Microsoft.AspNetCore.Server.Kestrel[13]
Connection id "0HMQ5R09TV075", Request id "0HMQ5R09TV075:00000002": An unhandled exception was thrown by the application.
System.Collections.Generic.KeyNotFoundException: The given key 'No auth token is provided' was not present in the dictionary.
at System.Collections.Generic.Dictionary`2.get_Item(TKey key)
at tests.Middleware.ProviderStateMiddleware.HandleProviderStatesRequest(HttpContext context) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 99
at tests.Middleware.ProviderStateMiddleware.Invoke(HttpContext context) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 72
at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.HttpProtocol.ProcessRequests[TContext](IHttpApplication`1 application)
fail: Microsoft.AspNetCore.Server.Kestrel[13]
Connection id "0HMQ5R09TV075", Request id "0HMQ5R09TV075:00000003": An unhandled exception was thrown by the application.
System.Collections.Generic.KeyNotFoundException: The given key 'No auth token is provided' was not present in the dictionary.
at System.Collections.Generic.Dictionary`2.get_Item(TKey key)
at tests.Middleware.ProviderStateMiddleware.HandleProviderStatesRequest(HttpContext context) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 99
at tests.Middleware.ProviderStateMiddleware.Invoke(HttpContext context) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 72
at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.HttpProtocol.ProcessRequests[TContext](IHttpApplication`1 application)
fail: Microsoft.AspNetCore.Server.Kestrel[13]
Connection id "0HMQ5R09TV075", Request id "0HMQ5R09TV075:00000004": An unhandled exception was thrown by the application.
System.Collections.Generic.KeyNotFoundException: The given key 'No auth token is provided' was not present in the dictionary.
at System.Collections.Generic.Dictionary`2.get_Item(TKey key)
at tests.Middleware.ProviderStateMiddleware.HandleProviderStatesRequest(HttpContext context) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 99
at tests.Middleware.ProviderStateMiddleware.Invoke(HttpContext context) in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/Middleware/ProviderStateMiddleware.cs:line 72
at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.HttpProtocol.ProcessRequests[TContext](IHttpApplication`1 application)
Verifying a pact between ApiClient and ProductService
A valid request for a product
Given No auth token is provided
Request Failed - One or more of the setup state change handlers has failed
A valid request for all products
Given no products exist
returns a response which
has status code 200 (FAILED)
includes headers
"Content-Type" with value "application/json; charset=utf-8" (FAILED)
has a matching body (FAILED)
A valid request for a product
Given product with ID 10 exists
returns a response which
has status code 200 (FAILED)
includes headers
"Content-Type" with value "application/json; charset=utf-8" (FAILED)
has a matching body (FAILED)
A valid request for a product
Given product with ID 11 does not exist
returns a response which
has status code 404 (FAILED)
has a matching body (OK)
A valid request for all products
Given products exist
returns a response which
has status code 200 (FAILED)
includes headers
"Content-Type" with value "application/json; charset=utf-8" (FAILED)
has a matching body (FAILED)
Failures:
1) Verifying a pact between ApiClient and ProductService Given No auth token is provided - A valid request for a product - One or more of the setup state change handlers has failed
2) Verifying a pact between ApiClient and ProductService Given no products exist - A valid request for all products
2.1) has a matching body
/ -> Expected body Present(2 bytes) but was empty
2.2) has status code 200
expected 200 but was 401
2.3) includes header 'Content-Type' with value '"application/json; charset=utf-8"'
Expected header 'Content-Type' to have value '"application/json; charset=utf-8"' but was ''
3) Verifying a pact between ApiClient and ProductService Given product with ID 10 exists - A valid request for a product
3.1) has a matching body
/ -> Expected body Present(65 bytes) but was empty
3.2) has status code 200
expected 200 but was 401
3.3) includes header 'Content-Type' with value '"application/json; charset=utf-8"'
Expected header 'Content-Type' to have value '"application/json; charset=utf-8"' but was ''
4) Verifying a pact between ApiClient and ProductService Given product with ID 11 does not exist - A valid request for a product
4.1) has status code 404
expected 404 but was 401
5) Verifying a pact between ApiClient and ProductService Given products exist - A valid request for all products
5.1) has a matching body
/ -> Expected body Present(130 bytes) but was empty
5.2) has status code 200
expected 200 but was 401
5.3) includes header 'Content-Type' with value '"application/json; charset=utf-8"'
Expected header 'Content-Type' to have value '"application/json; charset=utf-8"' but was ''
There were 5 pact failures
[xUnit.net 00:00:03.30] tests.ProductTest.EnsureProviderApiHonoursPactWithConsumer [FAIL]
Failed tests.ProductTest.EnsureProviderApiHonoursPactWithConsumer [2 s]
Error Message:
PactNet.Exceptions.PactFailureException : Pact verification failed
Stack Trace:
at PactNet.Verifier.InteropVerifierProvider.Execute()
at PactNet.Verifier.PactVerifierSource.Verify()
at tests.ProductTest.EnsureProviderApiHonoursPactWithConsumer() in /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/ProductTest.cs:line 43
Standard Output Messages:
Starting verification...
Pact verification failed
Verifier Output
---------------
Verifying a pact between ApiClient and ProductService
A valid request for a product
Given No auth token is provided
Request Failed - One or more of the setup state change handlers has failed
A valid request for all products
Given no products exist
returns a response which
has status code 200 (FAILED)
includes headers
"Content-Type" with value "application/json; charset=utf-8" (FAILED)
has a matching body (FAILED)
A valid request for a product
Given product with ID 10 exists
returns a response which
has status code 200 (FAILED)
includes headers
"Content-Type" with value "application/json; charset=utf-8" (FAILED)
has a matching body (FAILED)
A valid request for a product
Given product with ID 11 does not exist
returns a response which
has status code 404 (FAILED)
has a matching body (OK)
A valid request for all products
Given products exist
returns a response which
has status code 200 (FAILED)
includes headers
"Content-Type" with value "application/json; charset=utf-8" (FAILED)
has a matching body (FAILED)
Failures:
1) Verifying a pact between ApiClient and ProductService Given No auth token is provided - A valid request for a product - One or more of the setup state change handlers has failed
2) Verifying a pact between ApiClient and ProductService Given no products exist - A valid request for all products
2.1) has a matching body
/ -> Expected body Present(2 bytes) but was empty
2.2) has status code 200
expected 200 but was 401
2.3) includes header 'Content-Type' with value '"application/json; charset=utf-8"'
Expected header 'Content-Type' to have value '"application/json; charset=utf-8"' but was ''
3) Verifying a pact between ApiClient and ProductService Given product with ID 10 exists - A valid request for a product
3.1) has a matching body
/ -> Expected body Present(65 bytes) but was empty
3.2) has status code 200
expected 200 but was 401
3.3) includes header 'Content-Type' with value '"application/json; charset=utf-8"'
Expected header 'Content-Type' to have value '"application/json; charset=utf-8"' but was ''
4) Verifying a pact between ApiClient and ProductService Given product with ID 11 does not exist - A valid request for a product
4.1) has status code 404
expected 404 but was 401
5) Verifying a pact between ApiClient and ProductService Given products exist - A valid request for all products
5.1) has a matching body
/ -> Expected body Present(130 bytes) but was empty
5.2) has status code 200
expected 200 but was 401
5.3) includes header 'Content-Type' with value '"application/json; charset=utf-8"'
Expected header 'Content-Type' to have value '"application/json; charset=utf-8"' but was ''
There were 5 pact failures
Verifier Logs
-------------
2023-04-25T21:57:35.018185Z INFO ThreadId(09) pact_verifier: Running setup provider state change handler 'No auth token is provided' for 'A valid request for a product'
2023-04-25T21:57:36.301488Z ERROR ThreadId(09) pact_verifier: Provider setup state change for 'No auth token is provided' has failed - MismatchResult::Error("Invalid status code: 500", None)
2023-04-25T21:57:36.460737Z INFO ThreadId(09) pact_verifier: Running setup provider state change handler 'no products exist' for 'A valid request for all products'
2023-04-25T21:57:36.630956Z INFO ThreadId(09) pact_verifier: Running provider verification for 'A valid request for all products'
2023-04-25T21:57:36.632136Z INFO ThreadId(09) pact_verifier::provider_client: Sending request to provider at http://127.0.0.1:9001/
2023-04-25T21:57:36.632140Z INFO ThreadId(09) pact_verifier::provider_client: Sending request HTTP Request ( method: GET, path: /api/products, query: None, headers: None, body: Missing )
2023-04-25T21:57:36.634834Z INFO ThreadId(09) pact_verifier::provider_client: Received response: HTTP Response ( status: 401, headers: Some({"date": ["Tue", "25 Apr 2023 21:57:35 GMT"], "server": ["Kestrel"], "content-length": ["0"]}), body: Empty )
2023-04-25T21:57:36.634874Z INFO ThreadId(09) pact_matching: comparing to expected response: HTTP Response ( status: 200, headers: Some({"Content-Type": ["application/json; charset=utf-8"]}), body: Present(2 bytes) )
2023-04-25T21:57:36.784738Z INFO ThreadId(09) pact_verifier: Running setup provider state change handler 'product with ID 10 exists' for 'A valid request for a product'
2023-04-25T21:57:36.932746Z INFO ThreadId(09) pact_verifier: Running provider verification for 'A valid request for a product'
2023-04-25T21:57:36.932784Z INFO ThreadId(09) pact_verifier::provider_client: Sending request to provider at http://127.0.0.1:9001/
2023-04-25T21:57:36.932786Z INFO ThreadId(09) pact_verifier::provider_client: Sending request HTTP Request ( method: GET, path: /api/products/10, query: None, headers: Some({"Authorization": ["Bearer 2019-01-14T11:34:18.045Z"]}), body: Missing )
2023-04-25T21:57:36.936515Z INFO ThreadId(09) pact_verifier::provider_client: Received response: HTTP Response ( status: 401, headers: Some({"date": ["Tue", "25 Apr 2023 21:57:36 GMT"], "content-length": ["0"], "server": ["Kestrel"]}), body: Empty )
2023-04-25T21:57:36.936528Z INFO ThreadId(09) pact_matching: comparing to expected response: HTTP Response ( status: 200, headers: Some({"Content-Type": ["application/json; charset=utf-8"]}), body: Present(65 bytes) )
2023-04-25T21:57:37.083492Z INFO ThreadId(09) pact_verifier: Running setup provider state change handler 'product with ID 11 does not exist' for 'A valid request for a product'
2023-04-25T21:57:37.229871Z INFO ThreadId(09) pact_verifier: Running provider verification for 'A valid request for a product'
2023-04-25T21:57:37.229899Z INFO ThreadId(09) pact_verifier::provider_client: Sending request to provider at http://127.0.0.1:9001/
2023-04-25T21:57:37.229900Z INFO ThreadId(09) pact_verifier::provider_client: Sending request HTTP Request ( method: GET, path: /api/products/11, query: None, headers: None, body: Missing )
2023-04-25T21:57:37.230174Z INFO ThreadId(09) pact_verifier::provider_client: Received response: HTTP Response ( status: 401, headers: Some({"date": ["Tue", "25 Apr 2023 21:57:36 GMT"], "server": ["Kestrel"], "content-length": ["0"]}), body: Empty )
2023-04-25T21:57:37.230181Z INFO ThreadId(09) pact_matching: comparing to expected response: HTTP Response ( status: 404, headers: None, body: Missing )
2023-04-25T21:57:37.379565Z INFO ThreadId(09) pact_verifier: Running setup provider state change handler 'products exist' for 'A valid request for all products'
2023-04-25T21:57:37.531002Z INFO ThreadId(09) pact_verifier: Running provider verification for 'A valid request for all products'
2023-04-25T21:57:37.531038Z INFO ThreadId(09) pact_verifier::provider_client: Sending request to provider at http://127.0.0.1:9001/
2023-04-25T21:57:37.531039Z INFO ThreadId(09) pact_verifier::provider_client: Sending request HTTP Request ( method: GET, path: /api/products, query: None, headers: Some({"Authorization": ["Bearer 2019-01-14T11:34:18.045Z"]}), body: Missing )
2023-04-25T21:57:37.531277Z INFO ThreadId(09) pact_verifier::provider_client: Received response: HTTP Response ( status: 401, headers: Some({"server": ["Kestrel"], "content-length": ["0"], "date": ["Tue", "25 Apr 2023 21:57:36 GMT"]}), body: Empty )
2023-04-25T21:57:37.531286Z INFO ThreadId(09) pact_matching: comparing to expected response: HTTP Response ( status: 200, headers: Some({"Content-Type": ["application/json; charset=utf-8"]}), body: Present(130 bytes) )
Failed! - Failed: 1, Passed: 0, Skipped: 0, Total: 1, Duration: < 1 ms - /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/bin/Debug/net6.0/tests.dll (net6.0)
Oh, dear. More tests are failing. Can you understand why? If you can't don't worry, we will find out in the next step!
Because our pact file has static data in it, our bearer token is now out of date, so when Pact verification passes it to the Provider we get a 401
. There are multiple ways to resolve this - mocking or stubbing out the authentication component is a common one. In our use case, we are going to use a process referred to as Request Filtering, using a RequestFilter
.
NOTE: This is an advanced concept and should be used carefully, as it has the potential to invalidate a contract by bypassing its constraints. See https://github.com/DiUS/pact-jvm/blob/master/provider/junit/README.md#modifying-the-requests-before-they-are-sent for more details on this.
The approach we are going to take to inject the header is as follows:
- If we receive any Authorization header, we override the incoming request with a valid (in time) Authorization header, and continue with whatever call was being made
- If we don't receive an Authorization header, we do nothing
NOTE: We are not considering the 403
scenario in this example.
We'll implement this as a Middleware, similarly to have we deal with provider states
.
In the folder Provider/tests/Middleware
add a new file called AuthTokenRequestFilter.cs
:
using System;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.Primitives;
namespace tests.Middleware
{
// STEP_10
public class AuthTokenRequestFilter
{
private const string AuthorizationHeaderKey = "Authorization";
private readonly RequestDelegate _next;
public AuthTokenRequestFilter(RequestDelegate next)
{
_next = next;
}
public async Task Invoke(HttpContext context)
{
if (context.Request.Headers.ContainsKey(AuthorizationHeaderKey))
{
context.Request.Headers.Remove(AuthorizationHeaderKey);
context.Request.Headers.Add(AuthorizationHeaderKey, HeaderValue());
}
await this._next(context);
}
private StringValues HeaderValue()
{
return $"Bearer {DateTime.Now:yyyy-MM-ddTHH:mm:ss.fffZ}";
}
}
}
Then wire the new middleware in Provider/tests/TestStartup.cs
// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
app.UseMiddleware<ProviderStateMiddleware>();
app.UseMiddleware<AuthTokenRequestFilter>(); // STEP_10
_proxy.Configure(app, env);
}
And finally, add the corresponding state handler Provider/tests/Middleware/ProviderStateMiddleware.cs
We map it to a valid product, that we don't want an authenticated user to get access to, they wont be able to unless they present an valid authentication token
_providerStates = new Dictionary<string, Action>
{
{ "products exist", ProductsExist },
{ "product with ID 10 exists", Product10Exists },
{ "product with ID 11 does not exist", Product11DoesNotExist }, // STEP_7
{ "no products exist", NoProductsExist }, // STEP_7
{ "No auth token is provided", Product10Exists } // STEP_10
};
We can now run the Provider tests
Run this command under Provider
:
dotnet test
Determining projects to restore...
All projects are up-to-date for restore.
provider -> /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/src/bin/Debug/net6.0/provider.dll
tests -> /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/bin/Debug/net6.0/tests.dll
Test run for /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/bin/Debug/net6.0/tests.dll (.NETCoreApp,Version=v6.0)
Microsoft (R) Test Execution Command Line Tool Version 17.3.1 (arm64)
Copyright (c) Microsoft Corporation. All rights reserved.
Starting test execution, please wait...
A total of 1 test files matched the specified pattern.
Verifying a pact between ApiClient and ProductService
A valid request for a product
Given No auth token is provided
returns a response which
has status code 401 (OK)
has a matching body (OK)
A valid request for all products
Given no products exist
returns a response which
has status code 200 (OK)
includes headers
"Content-Type" with value "application/json; charset=utf-8" (OK)
has a matching body (OK)
A valid request for a product
Given product with ID 10 exists
returns a response which
has status code 200 (OK)
includes headers
"Content-Type" with value "application/json; charset=utf-8" (OK)
has a matching body (OK)
A valid request for a product
Given product with ID 11 does not exist
returns a response which
has status code 404 (OK)
has a matching body (OK)
A valid request for all products
Given products exist
returns a response which
has status code 200 (OK)
includes headers
"Content-Type" with value "application/json; charset=utf-8" (OK)
has a matching body (OK)
Passed! - Failed: 0, Passed: 1, Skipped: 0, Total: 1, Duration: < 1 ms - /Users/saf/dev/DIUS/pact-workshop-dotnet-core-v3/Provider/tests/bin/Debug/net6.0/tests.dll (net6.0)