Merge pull request #4 from nextbss/custom-error-responses

NF - Custom error responses

.gitignore

@@ -32,3 +32,4 @@ build/
 ### VS Code ###
 .vscode/
 settings.xml
+target

pom.xml

@@ -68,6 +68,12 @@
                 </exclusion>
             </exclusions>
         </dependency>
+        <dependency>
+            <groupId>org.jetbrains.kotlin</groupId>
+            <artifactId>kotlin-reflect</artifactId>
+            <version>RELEASE</version>
+            <scope>compile</scope>
+        </dependency>
     </dependencies>
 
     <build>

src/main/kotlin/ao/co/nextbss/requirekt/AAACustomErrorViewModel.kt

@@ -0,0 +1,22 @@
+package ao.co.nextbss.requirekt
+
+import co.ao.nextbss.requirekt.annotation.ErrorResponse
+
+@ErrorResponse
+class AAACustomErrorViewModel(
+    var status: Int = 0,
+    var code: String? = null,
+    var message: String? = null,
+    var type: String? = null): AbstractErrorResponse() {
+
+    override fun toJSON(vararg args: ArrayList<Any>): String {
+        status = fromArgsAsInt(0, args)
+        code = fromArgsAsString(1, args)
+        message = fromArgsAsString(2, args)
+        type = fromArgsAsString(3, args)
+        return super.toJSON()
+    }
+}
+
+
+

src/main/kotlin/ao/co/nextbss/requirekt/AbstractErrorResponse.kt

@@ -0,0 +1,9 @@
+package ao.co.nextbss.requirekt
+
+import co.ao.nextbss.requirekt.interfaces.Converter
+
+abstract class AbstractErrorResponse: Converter {
+    override fun toJSON(vararg args: ArrayList<Any>): String {
+        return ErrorWrapper().toJsonString(this)
+    }
+}

src/main/kotlin/ao/co/nextbss/requirekt/ApiException.kt

@@ -2,4 +2,4 @@ package ao.co.nextbss.requirekt
 
 import org.springframework.http.HttpStatus
 
-class ApiException(val error: String, val status: HttpStatus = HttpStatus.BAD_REQUEST) : RuntimeException()
+class ApiException(val error: String, val status: Int = HttpStatus.BAD_REQUEST.value()) : RuntimeException()

src/main/kotlin/ao/co/nextbss/requirekt/CustomErrorBeanFinder.kt

@@ -0,0 +1,16 @@
+package ao.co.nextbss.requirekt
+
+import org.springframework.beans.factory.annotation.Autowired
+import org.springframework.context.annotation.ComponentScan
+import org.springframework.core.env.Environment
+import org.springframework.stereotype.Component
+
+@Component
+@ComponentScan(basePackages = [])
+open class CustomErrorBeanFinder {
+    @Autowired
+    lateinit var errors: List<AbstractErrorResponse>
+
+    @Autowired
+    lateinit var environment: Environment
+}

src/main/kotlin/ao/co/nextbss/requirekt/DefaultErrorViewModel.kt

@@ -0,0 +1,14 @@
+package ao.co.nextbss.requirekt
+
+import ao.co.nextbss.requirekt.AbstractErrorResponse
+import co.ao.nextbss.requirekt.annotation.ErrorResponse
+
+@ErrorResponse
+class DefaultErrorViewModel(val status: Int?,
+                            val code: String?,
+                            val message: String?
+) : AbstractErrorResponse() {
+    override fun toJSON(vararg args: ArrayList<Any>): String {
+        return super.toJSON()
+    }
+}

src/main/kotlin/ao/co/nextbss/requirekt/ErrorResponse.kt

@@ -0,0 +1,10 @@
+package ao.co.nextbss.requirekt
+
+import co.ao.nextbss.requirekt.annotation.ErrorResponse
+
+@ErrorResponse
+open class ErrorResponse: AbstractErrorResponse() {
+    override fun toJSON(vararg args: ArrayList<Any>): String {
+        return ErrorWrapper().toJsonString(this)
+    }
+}

src/main/kotlin/ao/co/nextbss/requirekt/ErrorWrapper.kt

@@ -2,8 +2,11 @@ package ao.co.nextbss.requirekt
 
 import co.ao.nextbss.Yoru
 
-internal class ErrorWrapper(val errors: List<ErrorViewModel>) {
-    fun toJsonString(): String {
+open class ErrorWrapper {
+    val errors = ArrayList<AbstractErrorResponse>()
+
+    fun toJsonString(error: AbstractErrorResponse): String {
+        errors.add(error)
         return Yoru<ErrorWrapper>().toJson(this)
     }
 }

src/main/kotlin/ao/co/nextbss/requirekt/Preconditions.kt

@@ -1,15 +1,73 @@
 package ao.co.nextbss.requirekt
 
+import org.springframework.beans.BeansException
+import org.springframework.context.ApplicationContext
+import org.springframework.context.ApplicationContextAware
+import org.springframework.core.SpringProperties
 import org.springframework.http.HttpStatus
+import org.springframework.stereotype.Component
+import java.lang.IllegalStateException
+import java.util.logging.Logger
+import kotlin.collections.ArrayList
 
 /**
  * Throws an [ApiException] with the result of calling [lazyMessage] if the [value] is false.
- * Note: HttpStatus is [Bad_REQUEST] by default
- *
+ * Note: HttpStatus is [Bad_REQUEST] by default.
  */
 inline fun require(value: Boolean, lazyMessage: () -> Any) {
     if (!value) {
-        throw ApiException(ErrorViewModel.singleJSON(HttpStatus.BAD_REQUEST, lazyMessage().toString()))
+        throw ApiException(
+            DefaultErrorViewModel(
+                HttpStatus.BAD_REQUEST.value(),
+                "",
+                lazyMessage().toString()
+            ).toJSON())
+    }
+}
+
+/**
+ * Throws an [ApiException] for a CustomError with the result of [args] if the [value] is false
+ */
+inline fun require(value: Boolean, vararg args: ArrayList<Any>,) {
+    val logger: Logger = Logger.getLogger("Preconditions")
+    if (!value) {
+        val customErrorBeanFinder = SpringContext.getBean(CustomErrorBeanFinder::class.java)
+        val errors: List<AbstractErrorResponse> = customErrorBeanFinder.errors
+        logger.info { "Number of error types found: ${errors.size} " }
+        errors.forEach { println(it.javaClass.canonicalName) }
+
+        val filteredListOfCustomErrors = errors.filterNot {
+            it.javaClass.canonicalName == "ao.co.nextbss.requirekt.DefaultErrorViewModel"
+                || it.javaClass.canonicalName == "ao.co.nextbss.requirekt.ErrorResponse"
+                || it.javaClass.canonicalName == "ao.co.nextbss.requirekt.ErrorResponse"
+        }
+
+        logger.info { "Number of filtered error types found: ${filteredListOfCustomErrors.size}" }
+
+        filteredListOfCustomErrors.forEach { println(it.javaClass.canonicalName) }
+
+        val nameOfCustomClassToInstantiate = if (customErrorBeanFinder.environment.activeProfiles.contains("test")) {
+              filteredListOfCustomErrors[0].javaClass.canonicalName
+        } else {
+            try {
+                filteredListOfCustomErrors[1].javaClass.canonicalName
+            } catch (e: IndexOutOfBoundsException) {
+                throw IllegalStateException("No CustomError added. Add a Custom Error that subclasses AbstractErrorResponse and annotate it with @ErrorResponse")
+            }
+        }
+
+        logger.info("Canonical name of class that will instantiated as a custom error: $nameOfCustomClassToInstantiate")
+
+        val customError: AbstractErrorResponse = Class.forName(nameOfCustomClassToInstantiate)
+            .getDeclaredConstructor().newInstance() as AbstractErrorResponse
+
+        throw ApiException(
+            customError.toJSON(*args),
+            fromArgsAsInt(
+                0,
+                args
+            )
+        )
     }
 }
 
@@ -19,7 +77,13 @@ inline fun require(value: Boolean, lazyMessage: () -> Any) {
  */
 inline fun require(value: Boolean, httpStatus: HttpStatus, lazyMessage: () -> Any) {
     if (!value) {
-        throw ApiException(ErrorViewModel.singleJSON(httpStatus, lazyMessage().toString()), httpStatus)
+        throw ApiException(
+            DefaultErrorViewModel(
+                httpStatus.value(),
+                "",
+                lazyMessage().toString()
+            ).toJSON(),
+            httpStatus.value())
     }
 }
 
@@ -29,12 +93,12 @@ inline fun require(value: Boolean, httpStatus: HttpStatus, lazyMessage: () -> An
  */
 inline fun require(value: Boolean, status: HttpStatus, errorCode: String, lazyMessage: () -> Any) {
     if (!value) {
-        throw ApiException(ErrorViewModel.singleJSON(
-                status,
+        throw ApiException(
+            DefaultErrorViewModel(
+                status.value(),
                 errorCode,
                 lazyMessage().toString()
-            ),
-            status = status
-        )
+            ).toJSON(),
+            status.value())
     }
 }

src/main/kotlin/ao/co/nextbss/requirekt/SpringContext.kt

@@ -0,0 +1,22 @@
+package ao.co.nextbss.requirekt
+
+import org.springframework.beans.BeansException
+import org.springframework.context.ApplicationContext
+import org.springframework.context.ApplicationContextAware
+import org.springframework.stereotype.Component
+
+@Component
+class SpringContext : ApplicationContextAware {
+    @Throws(BeansException::class)
+    override fun setApplicationContext(context: ApplicationContext?) {
+        Companion.context = context
+    }
+
+    companion object {
+        private var context: ApplicationContext? = null
+
+        fun <T : Any?> getBean(beanClass: Class<T>?): T {
+            return context!!.getBean(beanClass)
+        }
+    }
+}

src/main/kotlin/ao/co/nextbss/requirekt/annotation/ErrorResponse.kt

@@ -0,0 +1,11 @@
+package co.ao.nextbss.requirekt.annotation
+
+import org.springframework.stereotype.Component
+
+@Target(AnnotationTarget.TYPE, AnnotationTarget.CLASS)
+@Retention(AnnotationRetention.RUNTIME)
+@MustBeDocumented
+@Component
+annotation class ErrorResponse(
+
+)

src/main/kotlin/ao/co/nextbss/requirekt/extensions.kt

@@ -0,0 +1,17 @@
+package ao.co.nextbss.requirekt
+
+fun fromArgs(index: Int, args: Array<out ArrayList<Any>>): Any {
+    return args[0][index]
+}
+
+fun fromArgsAsInt(index: Int, args: Array<out ArrayList<Any>>): Int {
+    return args[0][index] as Int
+}
+
+fun fromArgsAsString(index: Int, args: Array<out ArrayList<Any>>): String {
+    return args[0][index] as String
+}
+
+fun fromArgsAsFloat(index: Int, args: Array<out ArrayList<Any>>): Float {
+    return args[0][index] as Float
+}

src/main/kotlin/ao/co/nextbss/requirekt/interfaces/Converter.kt

@@ -0,0 +1,5 @@
+package co.ao.nextbss.requirekt.interfaces
+
+interface Converter {
+    fun toJSON(vararg args: ArrayList<Any>): String
+}

src/test/kotlin/ao/co/nextbss/requirekt/RequireTest.kt

@@ -88,4 +88,27 @@ internal class RequireTest(
                 .jsonPath("$.['errors'].[0].['code']")
                 .value(""))
     }
+
+    @Test
+    @DisplayName("It Should Return custom error response in json")
+    fun itShouldReturnCustomErrorResponse() {
+        mockMvc.perform(MockMvcRequestBuilders.post("/api/v1/messages/xHrFuz/transfer"))
+            .andDo(MockMvcResultHandlers.print())
+            .andExpect(MockMvcResultMatchers.status().isForbidden)
+            .andExpect(
+                MockMvcResultMatchers
+                    .jsonPath("$.['errors'].[0].['message']")
+                    .value("Access forbidden. You are not allowed to administrate categories."))
+            .andExpect(
+                MockMvcResultMatchers
+                    .jsonPath("$.['errors'].[0].['code']")
+                    .value("104"))
+            .andExpect(
+                MockMvcResultMatchers
+                    .jsonPath("$.['errors'].[0].['type']")
+                    .value("authentication"))
+            .andExpect(MockMvcResultMatchers
+                .jsonPath("$.['errors'].[0].['status']")
+                .value("403"))
+    }
 }

src/test/kotlin/ao/co/nextbss/requirekt/RestApiController.kt

@@ -38,7 +38,19 @@ class RestApiController {
         require(false) {
             "Message is invalid"
         }
+        return ResponseEntity.ok().build()
+    }
 
+    @PostMapping("/xHrFuz/transfer")
+    fun custom(): ResponseEntity<Any> {
+        require(value = false,
+            arrayListOf(
+                HttpStatus.FORBIDDEN.value(),
+                "104",
+                "Access forbidden. You are not allowed to administrate categories.",
+                "authentication"
+            )
+        )
         return ResponseEntity.ok().build()
     }
-}
+}