Support 503 health DOWN responses, and add detection for inconsistent problem status codes

belgif-rest-problem-it/belgif-rest-problem-it-common/src/main/java/io/github/belgif/rest/problem/it/AbstractJacksonSerializationTest.java

@@ -195,6 +195,24 @@ void legacyInvalidParamProblem() throws IOException {
         assertThat(writeProblem(badRequestProblem)).isEqualToIgnoringWhitespace(json);
     }
 
+    @Test
+    void titleAndStatusOverride() throws IOException {
+        String json = "{\n"
+                + "   \"type\": \"urn:problem-type:belgif:badRequest\",\n"
+                + "   \"href\": \"https://www.test.be\",\n"
+                + "   \"title\": \"TEST\",\n"
+                + "   \"status\": 401,\n"
+                + "   \"detail\": \"Test\"\n"
+                + "}";
+        Problem problem = readProblem(json);
+        assertThat(problem).isInstanceOf(BadRequestProblem.class);
+        BadRequestProblem badRequestProblem = (BadRequestProblem) problem;
+        assertThat(badRequestProblem.getType()).isEqualTo(BadRequestProblem.TYPE_URI);
+        assertThat(badRequestProblem.getHref()).isEqualTo(URI.create("https://www.test.be"));
+        assertThat(badRequestProblem.getStatus()).isEqualTo(BadRequestProblem.STATUS);
+        assertThat(badRequestProblem.getTitle()).isEqualTo(BadRequestProblem.TITLE);
+    }
+
     @Test
     void unknownProblemWithMessage() throws IOException {
         String json = "{\n"

belgif-rest-problem-it/belgif-rest-problem-it-common/src/main/java/io/github/belgif/rest/problem/it/AbstractRestProblemIT.java

@@ -133,6 +133,18 @@ public void jacksonMismatchedInputFromBackend(String client) {
                 .body("type", equalTo("urn:problem-type:belgif:internalServerError"));
     }
 
+    @ParameterizedTest
+    @MethodSource("getClients")
+    public void inconsistentProblemStatusFromBackend(String client) {
+        getSpec().when().queryParam("client", client)
+                .get("/inconsistentProblemStatusFromBackend").then().assertThat()
+                .statusCode(400)
+                .body("type", equalTo("urn:problem-type:belgif:badRequest"))
+                .body("detail", equalTo("Bad Request with inconsistent problem status code"
+                        + " (caught successfully by frontend)"))
+                .body("status", equalTo(400));
+    }
+
     @Test
     public void notFound() {
         getSpec().when().get("/not/found").then().assertThat()
@@ -562,4 +574,13 @@ public void invalidJsonType() {
                 .body("issues[0].value", equalTo("twenty-two"));
     }
 
+    @ParameterizedTest
+    @MethodSource("getClients")
+    public void healthDown(String client) {
+        getSpec().when().queryParam("client", client)
+                .get("/healthDown").then().assertThat()
+                .statusCode(503)
+                .body("status", equalTo("DOWN"));
+    }
+
 }

belgif-rest-problem-it/belgif-rest-problem-it-common/src/main/java/io/github/belgif/rest/problem/it/ProblemPayloads.java

@@ -0,0 +1,19 @@
+package io.github.belgif.rest.problem.it;
+
+/**
+ * Problem payload constants.
+ */
+public class ProblemPayloads {
+
+    public static final String INCONSISTENT_STATUS_CODE = "{\n"
+            + "  \"type\": \"urn:problem-type:belgif:badRequest\",\n"
+            + "  \"href\": \"https://www.belgif.be/specification/rest/api-guide/problems/badRequest.html\",\n"
+            + "  \"title\": \"Bad Request\",\n"
+            + "  \"status\": 401,\n" // <- 401 instead of 400
+            + "  \"detail\": \"Bad Request with inconsistent problem status code\"\n"
+            + "}";
+
+    private ProblemPayloads() {
+    }
+
+}

belgif-rest-problem-it/belgif-rest-problem-jakarta-ee-it/pom.xml

@@ -62,6 +62,12 @@
       <scope>provided</scope>
       <version>3.0.1.Final</version>
     </dependency>
+    <dependency>
+      <groupId>org.slf4j</groupId>
+      <artifactId>slf4j-api</artifactId>
+      <version>2.0.19</version>
+      <scope>provided</scope>
+    </dependency>
     <dependency>
       <groupId>org.junit.jupiter</groupId>
       <artifactId>junit-jupiter</artifactId>

belgif-rest-problem-it/belgif-rest-problem-jakarta-ee-it/src/main/java/io/github/belgif/rest/problem/Backend.java

@@ -31,4 +31,12 @@ public interface Backend {
     @Path("/jacksonMismatchedInput")
     Response jacksonMismatchedInput();
 
+    @GET
+    @Path("/inconsistentProblemStatus")
+    Response inconsistentProblemStatus();
+
+    @GET
+    @Path("/healthDown")
+    Response healthDown();
+
 }

belgif-rest-problem-it/belgif-rest-problem-jakarta-ee-it/src/main/java/io/github/belgif/rest/problem/BackendImpl.java

@@ -1,6 +1,8 @@
 package io.github.belgif.rest.problem;
 
 import java.net.URI;
+import java.util.HashMap;
+import java.util.Map;
 
 import jakarta.enterprise.context.RequestScoped;
 import jakarta.ws.rs.core.MediaType;
@@ -9,6 +11,7 @@
 import com.acme.custom.CustomProblem;
 
 import io.github.belgif.rest.problem.api.Problem;
+import io.github.belgif.rest.problem.it.ProblemPayloads;
 import io.github.belgif.rest.problem.it.model.JacksonModel;
 
 @RequestScoped
@@ -56,4 +59,22 @@ public Response jacksonMismatchedInput() {
         return Response.ok(model, MediaType.APPLICATION_JSON_TYPE).build();
     }
 
+    @Override
+    public Response inconsistentProblemStatus() {
+        return Response.status(402) // -> HTTP status code 402 instead of 400
+                .type("application/problem+json")
+                .entity(ProblemPayloads.INCONSISTENT_STATUS_CODE) // -> problem status code 401 instead of 400
+                .build();
+    }
+
+    @Override
+    public Response healthDown() {
+        Map<String, String> response = new HashMap<>();
+        response.put("status", "DOWN");
+        return Response.status(Response.Status.SERVICE_UNAVAILABLE)
+                .type(MediaType.APPLICATION_JSON_TYPE)
+                .entity(response)
+                .build();
+    }
+
 }

belgif-rest-problem-it/belgif-rest-problem-jakarta-ee-it/src/main/java/io/github/belgif/rest/problem/Frontend.java

@@ -73,6 +73,10 @@ public interface Frontend {
     @Path("/jacksonMismatchedInputFromBackend")
     Response jacksonMismatchedInputFromBackend(@QueryParam("client") Client client);
 
+    @GET
+    @Path("/inconsistentProblemStatusFromBackend")
+    Response inconsistentProblemStatusFromBackend(@QueryParam("client") Client client);
+
     @GET
     @Path("/beanValidation/queryParameter")
     Response beanValidationQueryParameter(@QueryParam("param") @NotNull @Positive Integer p,
@@ -118,4 +122,8 @@ Response beanValidationQueryParameter(@QueryParam("param") @NotNull @Positive In
     @Path("/jackson/mismatchedInputException")
     Response jacksonMismatchedInputException(@Valid JacksonModel body);
 
+    @GET
+    @Path("/healthDown")
+    Response healthDown(@QueryParam("client") Client client);
+
 }

belgif-rest-problem-it/belgif-rest-problem-jakarta-ee-it/src/main/java/io/github/belgif/rest/problem/FrontendImpl.java

@@ -14,10 +14,13 @@
 import jakarta.ws.rs.Path;
 import jakarta.ws.rs.PathParam;
 import jakarta.ws.rs.QueryParam;
+import jakarta.ws.rs.WebApplicationException;
 import jakarta.ws.rs.core.Response;
 
 import org.eclipse.microprofile.rest.client.RestClientBuilder;
 import org.jboss.resteasy.client.jaxrs.internal.ResteasyClientBuilderImpl;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import com.acme.custom.CustomProblem;
 
@@ -37,6 +40,8 @@
 @Path("/frontend")
 public class FrontendImpl implements Frontend {
 
+    private static final Logger LOGGER = LoggerFactory.getLogger(FrontendImpl.class);
+
     private static final URI BASE_URI =
             URI.create("http://" + System.getProperty("jboss.bind.address") + ":8080/rest-problem");
 
@@ -266,6 +271,67 @@ public Response jacksonMismatchedInputFromBackend(Client client) {
         throw new IllegalStateException("Unsupported client " + client);
     }
 
+    @Override
+    public Response inconsistentProblemStatusFromBackend(Client client) {
+        try {
+            if (client == null || client == Client.MICROPROFILE) {
+                return microprofileClient.inconsistentProblemStatus();
+            } else if (client == Client.JAXRS) {
+                return jaxRsClient.target(BASE_URI).path("backend/inconsistentProblemStatus").request().get();
+            } else if (client == Client.JAXRS_ASYNC) {
+                try {
+                    jaxRsClient.target(BASE_URI).path("backend/inconsistentProblemStatus").request().async().get()
+                            .get();
+                } catch (InterruptedException e) {
+                    Thread.currentThread().interrupt();
+                    throw new RuntimeException(e);
+                } catch (ExecutionException e) {
+                    throw new RuntimeException(e);
+                }
+            } else if (client == Client.RESTEASY) {
+                return resteasyClient.target(BASE_URI).path("backend/inconsistentProblemStatus").request().get();
+            } else if (client == Client.RESTEASY_PROXY) {
+                return resteasyProxyClient.inconsistentProblemStatus();
+            }
+            throw new IllegalStateException("Unsupported client " + client);
+        } catch (BadRequestProblem e) {
+            e.setDetail(e.getDetail() + " (caught successfully by frontend)");
+            throw e;
+        }
+    }
+
+    @Override
+    public Response healthDown(@QueryParam("client") Client client) {
+        try {
+            if (client == null || client == Client.MICROPROFILE) {
+                return microprofileClient.healthDown();
+            } else if (client == Client.JAXRS) {
+                return jaxRsClient.target(BASE_URI).path("backend/healthDown").request().get();
+            } else if (client == Client.JAXRS_ASYNC) {
+                try {
+                    return jaxRsClient.target(BASE_URI).path("backend/healthDown").request().async()
+                            .get().get();
+                } catch (InterruptedException e) {
+                    Thread.currentThread().interrupt();
+                    throw new RuntimeException(e);
+                } catch (ExecutionException e) {
+                    throw new RuntimeException(e);
+                }
+            } else if (client == Client.RESTEASY) {
+                return resteasyClient.target(BASE_URI).path("backend/healthDown").request().get();
+            } else if (client == Client.RESTEASY_PROXY) {
+                return resteasyProxyClient.healthDown();
+            }
+        } catch (WebApplicationException e) {
+            if (e.getResponse().getStatus() == Response.Status.SERVICE_UNAVAILABLE.getStatusCode()) {
+                LOGGER.info("Caught WebApplicationException with status 503");
+                return e.getResponse();
+            }
+            throw e;
+        }
+        throw new IllegalStateException("Unsupported client " + client);
+    }
+
     @Override
     public Response beanValidationQueryParameter(Integer p, String o) {
         return Response.ok("param: " + p + ", other: " + o).build();

belgif-rest-problem-it/belgif-rest-problem-java-ee-it/pom.xml

@@ -162,6 +162,12 @@
       <version>8.0.0</version>
       <scope>provided</scope>
     </dependency>
+    <dependency>
+      <groupId>org.slf4j</groupId>
+      <artifactId>slf4j-api</artifactId>
+      <version>2.0.19</version>
+      <scope>provided</scope>
+    </dependency>
     <dependency>
       <groupId>org.jboss.resteasy</groupId>
       <artifactId>resteasy-client-microprofile</artifactId>

belgif-rest-problem-it/belgif-rest-problem-java-ee-it/src/main/java/io/github/belgif/rest/problem/Backend.java

@@ -31,4 +31,12 @@ public interface Backend {
     @Path("/jacksonMismatchedInput")
     Response jacksonMismatchedInput();
 
+    @GET
+    @Path("/inconsistentProblemStatus")
+    Response inconsistentProblemStatus();
+
+    @GET
+    @Path("/healthDown")
+    Response healthDown();
+
 }

belgif-rest-problem-it/belgif-rest-problem-java-ee-it/src/main/java/io/github/belgif/rest/problem/BackendImpl.java

@@ -1,6 +1,8 @@
 package io.github.belgif.rest.problem;
 
 import java.net.URI;
+import java.util.HashMap;
+import java.util.Map;
 
 import javax.enterprise.context.RequestScoped;
 import javax.ws.rs.core.MediaType;
@@ -9,6 +11,7 @@
 import com.acme.custom.CustomProblem;
 
 import io.github.belgif.rest.problem.api.Problem;
+import io.github.belgif.rest.problem.it.ProblemPayloads;
 import io.github.belgif.rest.problem.it.model.JacksonModel;
 
 @RequestScoped
@@ -56,4 +59,22 @@ public Response jacksonMismatchedInput() {
         return Response.ok(model, MediaType.APPLICATION_JSON_TYPE).build();
     }
 
+    @Override
+    public Response inconsistentProblemStatus() {
+        return Response.status(402) // -> HTTP status code 402 instead of 400
+                .type("application/problem+json")
+                .entity(ProblemPayloads.INCONSISTENT_STATUS_CODE) // -> problem status code 401 instead of 400
+                .build();
+    }
+
+    @Override
+    public Response healthDown() {
+        Map<String, String> response = new HashMap<>();
+        response.put("status", "DOWN");
+        return Response.status(Response.Status.SERVICE_UNAVAILABLE)
+                .type(MediaType.APPLICATION_JSON_TYPE)
+                .entity(response)
+                .build();
+    }
+
 }

belgif-rest-problem-it/belgif-rest-problem-java-ee-it/src/main/java/io/github/belgif/rest/problem/Frontend.java

@@ -73,6 +73,10 @@ public interface Frontend {
     @Path("/jacksonMismatchedInputFromBackend")
     Response jacksonMismatchedInputFromBackend(@QueryParam("client") Client client);
 
+    @GET
+    @Path("/inconsistentProblemStatusFromBackend")
+    Response inconsistentProblemStatusFromBackend(@QueryParam("client") Client client);
+
     @GET
     @Path("/beanValidation/queryParameter")
     Response beanValidationQueryParameter(@QueryParam("param") @NotNull @Positive Integer p,
@@ -118,4 +122,8 @@ Response beanValidationQueryParameter(@QueryParam("param") @NotNull @Positive In
     @Path("/jackson/mismatchedInputException")
     Response jacksonMismatchedInputException(@Valid JacksonModel body);
 
+    @GET
+    @Path("/healthDown")
+    Response healthDown(@QueryParam("client") Client client);
+
 }