Merge pull request #101 from zalando/feature/custom-constraint-violat…

…ion-type

Made problem type configurable

src/main/java/org/zalando/problem/spring/web/advice/validation/BaseBindingResultAdviceTrait.java

@@ -21,10 +21,10 @@ default Violation createViolation(final ObjectError error) {
         return new Violation(fieldName, error.getDefaultMessage());
     }
 
-    default List<Violation> createViolations(BindingResult bindingResult) {
-      return Stream.concat(
-              bindingResult.getFieldErrors().stream().map(this::createViolation),
-              bindingResult.getGlobalErrors().stream().map(this::createViolation)).collect(toList());
+    default List<Violation> createViolations(final BindingResult result) {
+        final Stream<Violation> fieldErrors = result.getFieldErrors().stream().map(this::createViolation);
+        final Stream<Violation> globalErrors = result.getGlobalErrors().stream().map(this::createViolation);
+        return Stream.concat(fieldErrors, globalErrors).collect(toList());
     }
 
 }

src/main/java/org/zalando/problem/spring/web/advice/validation/BaseValidationAdviceTrait.java

@@ -6,6 +6,7 @@
 import org.zalando.problem.spring.web.advice.AdviceTrait;
 
 import javax.ws.rs.core.Response.StatusType;
+import java.net.URI;
 import java.util.Collection;
 import java.util.List;
 
@@ -15,6 +16,10 @@
 
 interface BaseValidationAdviceTrait extends AdviceTrait {
 
+    default URI defaultConstraintViolationType() {
+        return ConstraintViolationProblem.TYPE;
+    }
+
     default StatusType defaultConstraintViolationStatus() {
         return BAD_REQUEST;
     }
@@ -32,13 +37,17 @@ default String formatFieldName(final String fieldName) {
     default ResponseEntity<Problem> newConstraintViolationProblem(final Throwable throwable,
         final Collection<Violation> stream, final NativeWebRequest request) {
 
+        final URI type = defaultConstraintViolationType();
         final StatusType status = defaultConstraintViolationStatus();
+
         final List<Violation> violations = stream.stream()
             // sorting to make tests deterministic
             .sorted(comparing(Violation::getField).thenComparing(Violation::getMessage))
             .collect(toList());
 
-        return create(throwable, new ConstraintViolationProblem(status, violations), request);
+        final Problem problem = new ConstraintViolationProblem(type, status, violations);
+
+        return create(throwable, problem, request);
     }
 
 }

src/main/java/org/zalando/problem/spring/web/advice/validation/ConstraintViolationProblem.java

@@ -1,10 +1,7 @@
 package org.zalando.problem.spring.web.advice.validation;
 
-import com.fasterxml.jackson.annotation.JsonCreator;
-import com.fasterxml.jackson.annotation.JsonTypeName;
 import org.zalando.problem.ThrowableProblem;
 
-import javax.annotation.Nullable;
 import javax.annotation.concurrent.Immutable;
 import javax.ws.rs.core.Response.StatusType;
 import java.net.URI;
@@ -13,30 +10,28 @@
 import java.util.List;
 
 @Immutable
-@JsonTypeName(ConstraintViolationProblem.TYPE_VALUE)
 public final class ConstraintViolationProblem extends ThrowableProblem {
 
     public static final String TYPE_VALUE = "https://zalando.github.io/problem/constraint-violation";
     public static final URI TYPE = URI.create(TYPE_VALUE);
 
+    private final URI type;
     private final StatusType status;
-    private final String detail;
     private final List<Violation> violations;
 
     public ConstraintViolationProblem(final StatusType status, final List<Violation> violations) {
-        this(status, null, new ArrayList<>(violations));
+        this(TYPE, status, new ArrayList<>(violations));
     }
 
-    @JsonCreator
-    ConstraintViolationProblem(final StatusType status, @Nullable final String detail, final List<Violation> violations) {
+    ConstraintViolationProblem(final URI type, final StatusType status, final List<Violation> violations) {
+        this.type = type;
         this.status = status;
-        this.detail = detail;
         this.violations = Collections.unmodifiableList(violations);
     }
 
     @Override
     public URI getType() {
-        return TYPE;
+        return type;
     }
 
     @Override
@@ -49,11 +44,6 @@ public StatusType getStatus() {
         return status;
     }
 
-    @Override
-    public String getDetail() {
-        return detail;
-    }
-
     public List<Violation> getViolations() {
         return violations;
     }

src/main/java/org/zalando/problem/validation/ConstraintViolationProblemMixin.java

@@ -5,6 +5,8 @@
 
 import java.util.List;
 
+// TODO package private
+// TODO rename to MixIn
 public interface ConstraintViolationProblemMixin {
 
     @JsonProperty("violations")

src/main/java/org/zalando/problem/validation/ConstraintViolationProblemModule.java

@@ -9,15 +9,15 @@
 
 /**
  * A companion to {@link org.zalando.problem.ProblemModule} to enable serialization
- * of {@link ConstraintViolationProblem} and {@link Violation} without relying on autodetection.
+ * of {@link ConstraintViolationProblem} and {@link Violation} without relying on auto detection.
  */
-public class ConstraintViolationProblemModule extends Module {
-    @Override
-    public void setupModule(SetupContext context) {
-        final SimpleModule module = new SimpleModule();
+public final class ConstraintViolationProblemModule extends Module {
 
-        module.setMixInAnnotation(Violation.class, ViolationMixIn.class);
-        module.setMixInAnnotation(ConstraintViolationProblem.class, ConstraintViolationProblemMixin.class);
+    @Override
+    public void setupModule(final SetupContext context) {
+        final SimpleModule module = new SimpleModule()
+                .setMixInAnnotation(ConstraintViolationProblem.class, ConstraintViolationProblemMixin.class)
+                .setMixInAnnotation(Violation.class, ViolationMixIn.class);
 
         module.setupModule(context);
     }
@@ -27,10 +27,11 @@ public String getModuleName() {
         return ConstraintViolationProblemModule.class.getSimpleName();
     }
 
-    @SuppressWarnings("deprecation")
     @Override
+    @SuppressWarnings("deprecation")
     public Version version() {
         return VersionUtil.mavenVersionFor(ConstraintViolationProblemModule.class.getClassLoader(),
                 "org.zalando", "problem-spring-web");
     }
+
 }

src/main/java/org/zalando/problem/validation/ViolationMixIn.java

@@ -2,6 +2,7 @@
 
 import com.fasterxml.jackson.annotation.JsonProperty;
 
+// TODO package private
 public interface ViolationMixIn {
 
     @JsonProperty("field")

src/test/java/org/zalando/problem/spring/web/advice/validation/ConstraintViolationProblemModuleTest.java

@@ -0,0 +1,58 @@
+package org.zalando.problem.spring.web.advice.validation;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.MapperFeature;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import lombok.extern.slf4j.Slf4j;
+import org.junit.Test;
+import org.zalando.problem.ProblemModule;
+import org.zalando.problem.validation.ConstraintViolationProblemModule;
+
+import java.net.URI;
+
+import static com.jayway.jsonassert.JsonAssert.with;
+import static java.util.Collections.emptyList;
+import static java.util.Collections.singletonList;
+import static javax.ws.rs.core.Response.Status.BAD_REQUEST;
+import static org.hamcrest.Matchers.contains;
+import static org.hamcrest.Matchers.hasSize;
+import static org.hamcrest.Matchers.is;
+
+@Slf4j
+public class ConstraintViolationProblemModuleTest {
+
+    @Test
+    public void shouldSerializeWithoutAutoDetect() throws JsonProcessingException {
+        final ObjectMapper mapper = new ObjectMapper()
+                .disable(MapperFeature.AUTO_DETECT_FIELDS)
+                .disable(MapperFeature.AUTO_DETECT_GETTERS)
+                .disable(MapperFeature.AUTO_DETECT_IS_GETTERS)
+                .registerModule(new ProblemModule())
+                .registerModule(new ConstraintViolationProblemModule());
+
+        final Violation violation = new Violation("bob", "was missing");
+        final ConstraintViolationProblem unit = new ConstraintViolationProblem(BAD_REQUEST, singletonList(violation));
+
+        with(mapper.writeValueAsString(unit))
+                .assertThat("status", is(400))
+                .assertThat("type", is(ConstraintViolationProblem.TYPE_VALUE))
+                .assertThat("title", is("Constraint Violation"))
+                .assertThat("violations", hasSize(1))
+                .assertThat("violations.*.field", contains("bob"))
+                .assertThat("violations.*.message", contains("was missing"));
+    }
+
+    @Test
+    public void shouldSerializeCustomType() throws JsonProcessingException {
+        final ObjectMapper mapper = new ObjectMapper()
+                .registerModule(new ProblemModule())
+                .registerModule(new ConstraintViolationProblemModule());
+
+        final URI type = URI.create("foo");
+        final ConstraintViolationProblem unit = new ConstraintViolationProblem(type, BAD_REQUEST, emptyList());
+
+        with(mapper.writeValueAsString(unit))
+                .assertThat("type", is("foo"));
+    }
+
+}

src/test/java/org/zalando/problem/spring/web/advice/validation/ConstraintViolationProblemTest.java

@@ -8,7 +8,6 @@
 import static javax.ws.rs.core.Response.Status.BAD_REQUEST;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.hasSize;
-import static org.hamcrest.Matchers.is;
 
 public class ConstraintViolationProblemTest {
 
@@ -22,7 +21,6 @@ public void shouldCreateCopyOfViolations(){
         violations.clear();
 
         assertThat(problem.getViolations(), hasSize(1));
-        assertThat(problem.getViolations().get(0).getField(), is("x"));
-        assertThat(problem.getViolations().get(0).getMessage(), is("y"));
     }
+
 }