Polish common exception structure

Author: mduesterhoeft

src/main/kotlin/com/github/mduesterhoeft/router/ApiException.kt

@@ -1,15 +1,14 @@
 package com.github.mduesterhoeft.router
 
-import java.lang.RuntimeException
-
-class ApiException(
-    val statusCode: Int = 400,
+open class ApiException(
     message: String,
     val code: String,
-    val details: Map<String, Any> = emptyMap()
-) : RuntimeException(message) {
+    val httpResponseStatus: Int,
+    val details: Map<String, Any> = emptyMap(),
+    cause: Throwable? = null
+) : RuntimeException("[$code] $message", cause) {
 
     override fun toString(): String {
-        return "ApiException(statusCode=$statusCode, code=$code, details=$details, message=$message)"
+        return "ApiException(message='$message', code='$code', httpResponseStatus=$httpResponseStatus, details=$details, cause=$cause)"
     }
 }

src/main/kotlin/com/github/mduesterhoeft/router/RequestHandler.kt

@@ -55,7 +55,7 @@ abstract class RequestHandler : RequestHandler<APIGatewayProxyRequestEvent, APIG
         if (matchResults.any { it.matchPath && it.matchMethod && !it.matchContentType }) {
             return createErrorResponse(
                 input, ApiException(
-                    statusCode = 415,
+                    httpResponseStatus = 415,
                     message = "Unsupported Media Type",
                     code = "UNSUPPORTED_MEDIA_TYPE"
                 )
@@ -64,7 +64,7 @@ abstract class RequestHandler : RequestHandler<APIGatewayProxyRequestEvent, APIG
         if (matchResults.any { it.matchPath && it.matchMethod && !it.matchAcceptType }) {
             return createErrorResponse(
                 input, ApiException(
-                    statusCode = 406,
+                    httpResponseStatus = 406,
                     message = "Not Acceptable",
                     code = "NOT_ACCEPTABLE"
                 )
@@ -73,15 +73,15 @@ abstract class RequestHandler : RequestHandler<APIGatewayProxyRequestEvent, APIG
         if (matchResults.any { it.matchPath && !it.matchMethod }) {
             return createErrorResponse(
                 input, ApiException(
-                    statusCode = 405,
+                    httpResponseStatus = 405,
                     message = "Method Not Allowed",
                     code = "METHOD_NOT_ALLOWED"
                 )
             )
         }
         return createErrorResponse(
             input, ApiException(
-                statusCode = 404,
+                httpResponseStatus = 404,
                 message = "Not found",
                 code = "NOT_FOUND"
             )
@@ -97,7 +97,7 @@ abstract class RequestHandler : RequestHandler<APIGatewayProxyRequestEvent, APIG
                 "code" to ex.code,
                 "details" to ex.details
             )))
-            .withStatusCode(ex.statusCode)
+            .withStatusCode(ex.httpResponseStatus)
             .withHeaders(mapOf("Content-Type" to "application/json"))
 
     open fun <T> createResponse(input: APIGatewayProxyRequestEvent, response: ResponseEntity<T>): APIGatewayProxyResponseEvent {

src/main/kotlin/com/github/mduesterhoeft/router/Router.kt

@@ -64,7 +64,7 @@ class Router {
     }
 }
 
-interface Filter : (HandlerFunction<*, *>) -> HandlerFunction<*,*> {
+interface Filter : (HandlerFunction<*, *>) -> HandlerFunction<*, *> {
     companion object {
         operator fun invoke(fn: (HandlerFunction<*, *>) -> HandlerFunction<*, *>): Filter = object : Filter {
             override operator fun invoke(next: HandlerFunction<*, *>): HandlerFunction<*, *> = fn(next)
@@ -85,7 +85,7 @@ data class RouterFunction<I, T>(
     val handler: HandlerFunction<I, T>
 )
 
-data class Request<I>(val apiRequest: APIGatewayProxyRequestEvent, val body: I, val pathPattern: String) {
+data class Request<I>(val apiRequest: APIGatewayProxyRequestEvent, val body: I, val pathPattern: String = apiRequest.path) {
 
     val pathParameters by lazy { UriTemplate.from(pathPattern).extract(apiRequest.path) }
     fun getPathParameter(name: String) = pathParameters[name]

src/test/kotlin/com/github/mduesterhoeft/router/UriTemplateTest.kt

@@ -34,5 +34,4 @@ class UriTemplateTest {
             .isEqualTo(mapOf("first" to "first-value", "second" to "second-value"))
         then(UriTemplate.from("/some").extract("/some")).isEmpty()
     }
-
 }