Do not try to apply JsonView to failed responses

http-server-netty/src/main/java/io/micronaut/http/server/netty/jackson/JsonViewServerFilter.java

@@ -84,7 +84,10 @@ public final Publisher<? extends MutableHttpResponse<?>> doFilter(HttpRequest<?>
         if (routeInfo != null) {
             final Optional<Class<?>> viewClass = routeInfo.findAnnotation(JsonView.class)
                 .flatMap(AnnotationValue::classValue);
-            if (viewClass.isPresent()) {
+            if (viewClass.isPresent() &&
+                // if this is an error response, the response body does not come from the controller
+                !response.getAttributes().contains(HttpAttributes.EXCEPTION)) {
+
                 final Optional<?> optionalBody = response.getBody();
                 if (optionalBody.isPresent()) {
                     Object body = optionalBody.get();

http-server-netty/src/test/groovy/io/micronaut/http/server/netty/jackson/JsonViewController.groovy

@@ -17,10 +17,13 @@ package io.micronaut.http.server.netty.jackson
 
 import com.fasterxml.jackson.annotation.JsonView
 import io.micronaut.http.HttpResponse
+import io.micronaut.http.HttpStatus
 import io.micronaut.http.annotation.Body
 import io.micronaut.http.annotation.Controller
+import io.micronaut.http.annotation.Error
 import io.micronaut.http.annotation.Get
 import io.micronaut.http.annotation.Post
+import io.micronaut.http.hateoas.JsonError
 import reactor.core.publisher.Flux
 import reactor.core.publisher.Mono
 
@@ -77,4 +80,24 @@ class JsonViewController {
         assert model.password == null
         return HttpResponse.ok(model)
     }
+
+    @JsonView(Views.Public)
+    @Get("/failing")
+    TestModel failing() {
+        throw new Failure1()
+    }
+
+    @JsonView(Views.Public)
+    @Get("/failing-with-route")
+    TestModel failingWithRoute() {
+        throw new Failure2()
+    }
+
+    @Error
+    HttpResponse<JsonError> errorRoute(Failure2 f) {
+        return HttpResponse.status(HttpStatus.INTERNAL_SERVER_ERROR).body(new JsonError("failure2"));
+    }
+
+    static class Failure1 extends Exception {}
+    static class Failure2 extends Exception {}
 }

http-server-netty/src/test/groovy/io/micronaut/http/server/netty/jackson/JsonViewServerFilterSpec.groovy

@@ -20,6 +20,8 @@ import io.micronaut.core.type.Argument
 import io.micronaut.http.HttpRequest
 import io.micronaut.http.HttpResponse
 import io.micronaut.http.client.HttpClient
+import io.micronaut.http.client.exceptions.HttpClientResponseException
+import io.micronaut.http.hateoas.JsonError
 import io.micronaut.runtime.server.EmbeddedServer
 import spock.lang.AutoCleanup
 import spock.lang.Shared
@@ -126,4 +128,20 @@ class JsonViewServerFilterSpec extends Specification {
         rsp.body().birthdate == null
         rsp.body().password == null
     }
+
+    def "errors are written properly"() {
+        when:
+        client.toBlocking().exchange(HttpRequest.GET('/jsonview/failing'), TestModel)
+
+        then:
+        def f = thrown HttpClientResponseException
+        f.response.getBody(JsonError).get().message == "Internal Server Error"
+
+        when:
+        client.toBlocking().exchange(HttpRequest.GET('/jsonview/failing-with-route'))
+
+        then:
+        HttpClientResponseException e = thrown()
+        e.response.getBody(JsonError).get().message == "failure2"
+    }
 }