Tck: Tests for error handlers with flux controller methods (#10025)

http-server-tck/src/main/java/io/micronaut/http/server/tck/tests/ErrorHandlerFluxTest.java

@@ -0,0 +1,153 @@
+/*
+ * Copyright 2017-2023 original authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.micronaut.http.server.tck.tests;
+
+import io.micronaut.context.annotation.Requires;
+import io.micronaut.core.async.annotation.SingleResult;
+import io.micronaut.http.HttpRequest;
+import io.micronaut.http.HttpResponse;
+import io.micronaut.http.HttpStatus;
+import io.micronaut.http.annotation.Controller;
+import io.micronaut.http.annotation.Error;
+import io.micronaut.http.annotation.Get;
+import io.micronaut.http.client.exceptions.HttpClientException;
+import io.micronaut.http.tck.AssertionUtils;
+import io.micronaut.http.tck.HttpResponseAssertion;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.function.Executable;
+import reactor.core.publisher.Flux;
+
+import java.io.IOException;
+
+import static io.micronaut.http.tck.TestScenario.asserts;
+
+@SuppressWarnings({
+    "java:S5960", // We're allowed assertions, as these are used in tests only
+    "checkstyle:MissingJavadocType",
+    "checkstyle:DesignForExtension"
+})
+public class ErrorHandlerFluxTest {
+
+    public static final String SPEC_NAME = "ErrorHandlerFluxTest";
+
+    @Test
+    void testErrorHandlerWithFluxThrownException() throws IOException {
+        asserts(SPEC_NAME,
+            HttpRequest.GET("/errors/flux-exception"),
+            (server, request) -> AssertionUtils.assertThrows(server, request, HttpResponseAssertion.builder()
+                .status(HttpStatus.I_AM_A_TEAPOT)
+                .body("Your request is erroneous: Cannot process request.")
+                .build()));
+    }
+
+    @Test
+    void testErrorHandlerWithFluxSingleResultThrownException() throws IOException {
+        asserts(SPEC_NAME,
+            HttpRequest.GET("/errors/flux-single-exception"),
+            (server, request) -> AssertionUtils.assertThrows(server, request, HttpResponseAssertion.builder()
+                .status(HttpStatus.I_AM_A_TEAPOT)
+                .body("Your request is erroneous: Cannot process request.")
+                .build()));
+    }
+
+    @Test
+    void testErrorHandlerWithFluxChunkedSignaledImmediateError() throws IOException {
+        //NOTE - This demonstrates the current behavior of the error handler not getting invoked
+        //when writing a chunked response, even if the error is signaled before any data to be
+        //written to the response body. It would be ideal if in this case the error handler could
+        //still be invoked with the exception from the error signal.
+        asserts(SPEC_NAME,
+            HttpRequest.GET("/errors/flux-chunked-immediate-error"),
+            (server, request) -> AssertionUtils.assertThrows(server, request, HttpResponseAssertion.builder()
+                .status(HttpStatus.INTERNAL_SERVER_ERROR)
+                .body("Internal Server Error: Cannot process request.")
+                .build()));
+    }
+
+    @Test
+    void testErrorHandlerWithFluxChunkedSignaledDelayedError() throws IOException {
+        asserts(SPEC_NAME,
+            HttpRequest.GET("/errors/flux-chunked-delayed-error"),
+            (server, request) -> {
+                Executable e = () -> server.exchange(request);
+                Assertions.assertThrows(HttpClientException.class, e);
+            });
+    }
+
+    @Test
+    void testErrorHandlerWithFluxSingleResultSignaledError() throws IOException {
+        asserts(SPEC_NAME,
+            HttpRequest.GET("/errors/flux-single-error"),
+            (server, request) -> AssertionUtils.assertThrows(server, request, HttpResponseAssertion.builder()
+                .status(HttpStatus.I_AM_A_TEAPOT)
+                .body("Your request is erroneous: Cannot process request.")
+                .build()));
+    }
+
+    @Requires(property = "spec.name", value = SPEC_NAME)
+    @Controller("/errors")
+    static class ErrorController {
+
+        @Get("/flux-exception")
+        Flux<String> fluxException() {
+            throw new MyTestException("Cannot process request.");
+        }
+
+        @Get("/flux-single-exception")
+        @SingleResult
+        Flux<String> fluxSingleException() {
+            throw new MyTestException("Cannot process request.");
+        }
+
+        @Get("/flux-single-error")
+        @SingleResult
+        Flux<String> fluxSingleError() {
+            return Flux.error(new MyTestException("Cannot process request."));
+        }
+
+        @Get("/flux-chunked-immediate-error")
+        Flux<String> fluxChunkedImmediateError() {
+            return Flux.error(new MyTestException("Cannot process request."));
+        }
+
+        @Get("/flux-chunked-delayed-error")
+        Flux<String> fluxChunkedDelayedError() {
+            return Flux.just("1", "2", "3").handle((data, sink) -> {
+                if (data.equals("3")) {
+                    sink.error(new MyTestException("Cannot process request."));
+                } else {
+                    sink.next(data);
+                }
+            });
+        }
+
+        @Error(global = true)
+        public HttpResponse<String> handleMyTestException(HttpRequest<?> request, MyTestException exception) {
+            var error = "Your request is erroneous: " + exception.getMessage();
+            return HttpResponse.<String>status(HttpStatus.I_AM_A_TEAPOT, "Bad request")
+                .body(error);
+        }
+
+    }
+
+    static class MyTestException extends RuntimeException {
+
+        public MyTestException(String message) {
+            super(message);
+        }
+    }
+}