Add Basic Event Support

.gitignore

@@ -7,3 +7,6 @@ dist
 
 # VS Code
 .vscode
+
+# Intellij
+.idea

README.md

@@ -11,16 +11,17 @@ SendGrid-Mock serves as a simple server mocking the sendgrid-apis for developmen
 * Send mails `POST /v3/mail/send`
 
 * Retrieve sent mails `GET /api/mails`
-  * Filter capabilities are included and can be combined:
-    * **To**: `GET /api/mails?to=email@address.com`
-    * **Subject**:
-      * `GET /api/mails?subject=The subject` (*exact match*)
-      * `GET /api/mails?subject=%subject%` (*contains*)
-    * **Datetime**: `GET /api/mails?dateTimeSince=2020-12-06T10:00:00Z` (*[ISO-8601 format](https://en.wikipedia.org/wiki/ISO_8601)*)
+    * Filter capabilities are included and can be combined:
+        * **To**: `GET /api/mails?to=email@address.com`
+        * **Subject**:
+            * `GET /api/mails?subject=The subject` (*exact match*)
+            * `GET /api/mails?subject=%subject%` (*contains*)
+        * **Datetime**: `GET /api/mails?dateTimeSince=2020-12-06T10:00:00Z` (
+          *[ISO-8601 format](https://en.wikipedia.org/wiki/ISO_8601)*)
 
 * Delete sent mails `DELETE /api/mails`
-  * Filter capabilities are included and can be combined:
-    * **To**: `DELETE /api/mails?to=email@address.com`
+    * Filter capabilities are included and can be combined:
+        * **To**: `DELETE /api/mails?to=email@address.com`
 
 ### UI
 
@@ -29,21 +30,31 @@ SendGrid-Mock serves as a simple server mocking the sendgrid-apis for developmen
 
 ### Extras
 
-* Basic authentication support: Add basic authentication credentials by specifying environment variable `AUTHENTICATION` to the following format: `user1:passwordForUser1;user2:passwordForUser2`
+* Basic authentication support: Add basic authentication credentials by specifying environment variable `AUTHENTICATION`
+  to the following format: `user1:passwordForUser1;user2:passwordForUser2`
 
-* Request rate limiting: Both the actual SendGrid API server as well as the SSL server can be rate limited by specifying environment variables:
-  * `RATE_LIMIT_ENABLED`: `true` or `false` (default)
-  * `RATE_LIMIT_WINDOW_IN_MS`: The time window in milliseconds (default: `60000`)
-  * `RATE_LIMIT_MAX_REQUESTS`: The maximum number of requests allowed in the time window (default: `100`)
-  * `SSL_RATE_LIMIT_ENABLED`: `true` or `false` (default)
-  * `SSL_RATE_LIMIT_WINDOW_IN_MS`: The time window in milliseconds (default: `60000`)
-  * `SSL_RATE_LIMIT_MAX_REQUESTS`: The maximum number of requests allowed in the time window (default: `100`)
+* Request rate limiting: Both the actual SendGrid API server as well as the SSL server can be rate limited by specifying
+  environment variables:
+    * `RATE_LIMIT_ENABLED`: `true` or `false` (default)
+    * `RATE_LIMIT_WINDOW_IN_MS`: The time window in milliseconds (default: `60000`)
+    * `RATE_LIMIT_MAX_REQUESTS`: The maximum number of requests allowed in the time window (default: `100`)
+    * `SSL_RATE_LIMIT_ENABLED`: `true` or `false` (default)
+    * `SSL_RATE_LIMIT_WINDOW_IN_MS`: The time window in milliseconds (default: `60000`)
+    * `SSL_RATE_LIMIT_MAX_REQUESTS`: The maximum number of requests allowed in the time window (default: `100`)
 
-* By default, all emails older than 24 hours will be deleted. This can be configured using environment variable `MAIL_HISTORY_DURATION` which uses [ISO-8601 Duration format](https://en.wikipedia.org/wiki/ISO_8601#Durations) such as *'PT24H'*.
+* By default, all emails older than 24 hours will be deleted. This can be configured using environment
+  variable `MAIL_HISTORY_DURATION` which
+  uses [ISO-8601 Duration format](https://en.wikipedia.org/wiki/ISO_8601#Durations) such as *'PT24H'*.
+
+* Event support: Add basic [event](https://www.twilio.com/docs/sendgrid/for-developers/tracking-events/event#events)
+  support by specifying the environment variable `EVENT_DELIVERY_URL`. When set,
+  [delivered](https://www.twilio.com/docs/sendgrid/for-developers/tracking-events/event#delivered) events will be
+  sent to the specified webhook URL when an email is sent.
 
 ## Dockerized
 
-The SendGrid-Mock server and the UI are both contained in the same docker-image which you can pull from [Docker Hub](https://cloud.docker.com/u/ghashange/repository/docker/ghashange/sendgrid-mock) and start it via:
+The SendGrid-Mock server and the UI are both contained in the same docker-image which you can pull
+from [Docker Hub](https://cloud.docker.com/u/ghashange/repository/docker/ghashange/sendgrid-mock) and start it via:
 
 ```shell
 docker run -it -p 3000:3000 -e "API_KEY=sendgrid-api-key" ghashange/sendgrid-mock:1.9.2
@@ -63,7 +74,8 @@ docker run -it -p 3000:3000 -e "API_KEY=sendgrid-api-key" -e "CERT_DOMAINNAMES=[
 
 ## Development
 
-Setup with `npm ci` and start both server and UI concurrently with `npm run dev`. Per default the server is reachable via <http://localhost:3000> and the UI via <http://localhost:1234>.
+Setup with `npm ci` and start both server and UI concurrently with `npm run dev`. Per default the server is reachable
+via <http://localhost:3000> and the UI via <http://localhost:1234>.
 
 Some prepared HTTP calls can be found [here](./http-calls).
 
@@ -81,4 +93,5 @@ Create docker image with `docker build -t ghashange/sendgrid-mock:1.9.2 .`.
 
 3. Merge PR
 
-4. Create GitHub release and update [Docker Hub description](https://hub.docker.com/repository/docker/ghashange/sendgrid-mock)
+4. Create GitHub release and
+   update [Docker Hub description](https://hub.docker.com/repository/docker/ghashange/sendgrid-mock)

__mocks__/axios.js

@@ -0,0 +1,6 @@
+const axios = {
+  post: jest.fn(() => Promise.resolve({ data: {} })),
+  // Add other axios methods you use here
+};
+
+module.exports = axios;

package.json

@@ -28,6 +28,7 @@
   },
   "license": "MIT",
   "dependencies": {
+    "axios": "^1.7.2",
     "body-parser": "^1.20.1",
     "express": "^4.19.2",
     "express-basic-auth": "^1.2.0",

src/server/RequestHandler.js

@@ -95,11 +95,12 @@ const RequestHandler = (app, apiAuthenticationKey, mailHandler) => {
       const reqApiKey = req.headers.authorization;
 
       if (reqApiKey === `Bearer ${apiAuthenticationKey}`) {
+        const messageId = crypto.randomUUID();
 
-        mailHandler.addMail(req.body);
+        mailHandler.addMail(req.body, messageId);
 
         res.status(202).header({
-          'X-Message-ID': crypto.randomUUID(),
+          'X-Message-ID': messageId,
         }).send();
       } else {
         res.status(403).send({

src/server/handler/MailHandler.js

@@ -1,5 +1,8 @@
 const {loggerFactory} = require('../logger/log4js');
 
+const axios = require('axios');
+const crypto = require('crypto');
+
 const logger = loggerFactory('MailHandler');
 
 const mailWithTimestamp = (mail) => {
@@ -123,7 +126,7 @@ class MailHandler {
       .slice(paginationStart, paginationStart + paginationSize);
   }
 
-  addMail(mail) {
+  addMail(mail, messageId = crypto.randomUUID()) {
 
     this.#mails = [mailWithTimestamp(mail), ...this.#mails];
 
@@ -132,9 +135,34 @@ class MailHandler {
       return Date.parse(mail.datetime).valueOf() >= maxRetentionTime;
     });
 
+    if (process.env.EVENT_DELIVERY_URL) {
+      this.sendDeliveryEvents(mail, messageId);
+    }
+
     logMemoryUsage(this.#mails);
   }
 
+  sendDeliveryEvents(mail, messageId) {
+    const datetime = new Date();
+    const deliveredEvents = mail.personalizations
+      .flatMap(personalization => personalization.to)
+      .map(to => {
+        let event = {
+          email: to.email,
+          timestamp: datetime.getTime(),
+          event: 'delivered',
+          sg_event_id: crypto.randomUUID(),
+          sg_message_id: messageId,
+        };
+        event['smtp-id'] = crypto.randomUUID();
+        return event;
+      });
+
+    axios.post(process.env.EVENT_DELIVERY_URL, deliveredEvents)
+      .then(() => logger.debug(`Delivery events sent successfully to ${process.env.EVENT_DELIVERY_URL}`))
+      .catch((error) => logger.debug(`Failed to send delivery events to ${process.env.EVENT_DELIVERY_URL}`, error));
+  }
+
   clear(filterCriteria) {
 
     const filters = [