make i18n configurable (#329)

* make i18n configurable

* make translation configurable via alwaysDo(...) mechanism

* ResourceBundleSnippetTranslationResolver load resources only if used

* custom snippet translation test

* constraint translation

Author: MikeSafonov

spring-auto-restdocs-core/src/main/java/capital/scalable/restdocs/OperationAttributeHelper.java

@@ -7,9 +7,9 @@
  * 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
- *
+ * 
  *      http://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.
@@ -30,6 +30,8 @@
 import java.util.Map;
 
 import capital.scalable.restdocs.constraints.ConstraintReader;
+import capital.scalable.restdocs.i18n.SnippetTranslationManager;
+import capital.scalable.restdocs.i18n.SnippetTranslationResolver;
 import capital.scalable.restdocs.jackson.TypeMapping;
 import capital.scalable.restdocs.javadoc.JavadocReader;
 import capital.scalable.restdocs.misc.AuthorizationSnippet;
@@ -95,6 +97,19 @@ public static void setJavadocReader(MockHttpServletRequest request,
                 .put(JavadocReader.class.getName(), javadocReader);
     }
 
+    public static void setTranslationResolver(MockHttpServletRequest request, SnippetTranslationResolver translationResolver){
+        ((Map) request.getAttribute(ATTRIBUTE_NAME_CONFIGURATION))
+                .put(SnippetTranslationResolver.class.getName(), translationResolver);
+    }
+
+    public static SnippetTranslationResolver getTranslationResolver(Operation operation){
+        Object resolver = operation.getAttributes().get(SnippetTranslationResolver.class.getName());
+        if(resolver == null) {
+            return SnippetTranslationManager.getDefaultResolver();
+        }
+        return (SnippetTranslationResolver) resolver;
+    }
+
     public static RestDocumentationContext getDocumentationContext(Operation operation) {
         return (RestDocumentationContext) operation
                 .getAttributes().get(RestDocumentationContext.class.getName());

spring-auto-restdocs-core/src/main/java/capital/scalable/restdocs/constraints/ConstraintAndGroupDescriptionResolver.java

@@ -19,7 +19,6 @@
  */
 package capital.scalable.restdocs.constraints;
 
-import static capital.scalable.restdocs.i18n.SnippetTranslationResolver.translate;
 import static java.util.Collections.emptyList;
 import static java.util.Collections.singletonMap;
 import static org.apache.commons.lang3.StringUtils.isBlank;
@@ -31,6 +30,7 @@
 import java.util.List;
 import java.util.MissingResourceException;
 
+import capital.scalable.restdocs.i18n.SnippetTranslationResolver;
 import org.slf4j.Logger;
 import org.springframework.restdocs.constraints.Constraint;
 import org.springframework.restdocs.constraints.ConstraintDescriptionResolver;
@@ -42,9 +42,11 @@ public class ConstraintAndGroupDescriptionResolver implements
     static final String VALUE = "value";
 
     private final ConstraintDescriptionResolver delegate;
+    private final SnippetTranslationResolver translationResolver;
 
-    public ConstraintAndGroupDescriptionResolver(ConstraintDescriptionResolver delegate) {
+    public ConstraintAndGroupDescriptionResolver(ConstraintDescriptionResolver delegate, SnippetTranslationResolver translationResolver) {
         this.delegate = delegate;
+        this.translationResolver = translationResolver;
     }
 
     @Override
@@ -92,7 +94,7 @@ public String resolveGroupDescription(Class group, String constraintDescription)
     }
 
     private String fallbackGroupDescription(Class group, String constraintDescription) {
-        return translate("constraints-groups", constraintDescription, group.getSimpleName());
+        return translationResolver.translate("constraints-groups", constraintDescription, group.getSimpleName());
     }
 
     private String resolvePlainDescription(Constraint constraint) {

spring-auto-restdocs-core/src/main/java/capital/scalable/restdocs/constraints/ConstraintReaderImpl.java

@@ -21,7 +21,6 @@
 
 import static capital.scalable.restdocs.constraints.ConstraintAndGroupDescriptionResolver.VALUE;
 import static capital.scalable.restdocs.constraints.MethodParameterValidatorConstraintResolver.CONSTRAINT_CLASS;
-import static capital.scalable.restdocs.i18n.SnippetTranslationResolver.translate;
 import static capital.scalable.restdocs.util.FormatUtil.collectionToString;
 import static java.util.Collections.emptyList;
 import static java.util.Collections.emptyMap;
@@ -36,46 +35,51 @@
 import java.util.Collections;
 import java.util.List;
 
+import capital.scalable.restdocs.i18n.SnippetTranslationResolver;
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import org.apache.commons.lang3.StringUtils;
 import org.slf4j.Logger;
 import org.springframework.core.MethodParameter;
 import org.springframework.restdocs.constraints.Constraint;
+import org.springframework.restdocs.constraints.ConstraintDescriptionResolver;
 import org.springframework.restdocs.constraints.ConstraintDescriptions;
-import org.springframework.restdocs.constraints.ResourceBundleConstraintDescriptionResolver;
 
 public class ConstraintReaderImpl implements ConstraintReader {
 
     private static final Logger log = getLogger(ConstraintReaderImpl.class);
 
-    private final ConstraintAndGroupDescriptionResolver constraintDescriptionResolver;
+    private final ConstraintAndGroupDescriptionResolver constraintAndGroupDescriptionResolver;
 
     private final SkippableConstraintResolver skippableConstraintResolver;
 
     private final MethodParameterConstraintResolver constraintResolver;
 
     private final ObjectMapper objectMapper;
 
-    private ConstraintReaderImpl(MethodParameterConstraintResolver actualResolver, ObjectMapper objectMapper) {
-        constraintDescriptionResolver = new ConstraintAndGroupDescriptionResolver(
-                new ResourceBundleConstraintDescriptionResolver());
+    private final SnippetTranslationResolver translationResolver;
+
+    private ConstraintReaderImpl(MethodParameterConstraintResolver actualResolver, ObjectMapper objectMapper, SnippetTranslationResolver translationResolver,
+                                 ConstraintDescriptionResolver constraintDescriptionResolver) {
+        this.translationResolver = translationResolver;
+        constraintAndGroupDescriptionResolver = new ConstraintAndGroupDescriptionResolver(
+                constraintDescriptionResolver, translationResolver);
         skippableConstraintResolver = new SkippableConstraintResolver(
-                actualResolver, constraintDescriptionResolver);
+                actualResolver, constraintAndGroupDescriptionResolver);
         constraintResolver = new HumanReadableConstraintResolver(skippableConstraintResolver);
         this.objectMapper = objectMapper;
     }
 
-    public static ConstraintReaderImpl create(ObjectMapper objectMapper) {
-        return CONSTRAINT_CLASS != null ? createWithValidation(objectMapper) : createWithoutValidation(objectMapper);
+    public static ConstraintReaderImpl create(ObjectMapper objectMapper, SnippetTranslationResolver translationResolver, ConstraintDescriptionResolver constraintDescriptionResolver) {
+        return CONSTRAINT_CLASS != null ? createWithValidation(objectMapper, translationResolver, constraintDescriptionResolver) : createWithoutValidation(objectMapper, translationResolver, constraintDescriptionResolver);
     }
 
-    static ConstraintReaderImpl createWithoutValidation(ObjectMapper objectMapper) {
-        return new ConstraintReaderImpl(new NoOpMethodParameterConstraintResolver(), objectMapper);
+    static ConstraintReaderImpl createWithoutValidation(ObjectMapper objectMapper, SnippetTranslationResolver translationResolver, ConstraintDescriptionResolver constraintDescriptionResolver) {
+        return new ConstraintReaderImpl(new NoOpMethodParameterConstraintResolver(), objectMapper, translationResolver, constraintDescriptionResolver);
     }
 
-    static ConstraintReaderImpl createWithValidation(ObjectMapper objectMapper) {
-        return new ConstraintReaderImpl(new MethodParameterValidatorConstraintResolver(), objectMapper);
+    static ConstraintReaderImpl createWithValidation(ObjectMapper objectMapper, SnippetTranslationResolver translationResolver, ConstraintDescriptionResolver constraintDescriptionResolver) {
+        return new ConstraintReaderImpl(new MethodParameterValidatorConstraintResolver(), objectMapper, translationResolver, constraintDescriptionResolver);
     }
 
     @Override
@@ -85,7 +89,7 @@ public List<String> getOptionalMessages(Class<?> javaBaseClass, String javaField
 
     @Override
     public String getTypeSpecifier(Class<?> javaBaseClass) {
-        String message = constraintDescriptionResolver.resolveDescription(
+        String message = constraintAndGroupDescriptionResolver.resolveDescription(
                 new Constraint(javaBaseClass.getCanonicalName(), emptyMap()));
 
         // fallback
@@ -99,7 +103,7 @@ public String getTypeSpecifier(Class<?> javaBaseClass) {
     @Override
     public List<String> getConstraintMessages(Class<?> javaBaseClass, String javaFieldName) {
         ConstraintDescriptions constraints = new ConstraintDescriptions(javaBaseClass,
-                constraintResolver, constraintDescriptionResolver);
+                constraintResolver, constraintAndGroupDescriptionResolver);
         List<String> constraintMessages = new ArrayList<>();
         constraintMessages.addAll(constraints.descriptionsForProperty(javaFieldName));
         constraintMessages.addAll(getEnumConstraintMessage(javaBaseClass, javaFieldName));
@@ -112,7 +116,7 @@ public List<String> getConstraintMessages(MethodParameter param) {
         List<String> constraintMessages = new ArrayList<>();
         for (Constraint constraint : constraints) {
             constraintMessages.add(
-                    constraintDescriptionResolver.resolveDescription(constraint));
+                    constraintAndGroupDescriptionResolver.resolveDescription(constraint));
         }
         constraintMessages.addAll(getEnumConstraintMessage(param));
         Collections.sort(constraintMessages);
@@ -154,12 +158,12 @@ private List<String> getEnumConstraintMessage(Class<?> rawClass) {
 
         String value = collectionToString(serializedEnumValues);
         String enumName = enumClass.getCanonicalName();
-        String message = constraintDescriptionResolver.resolveDescription(
+        String message = constraintAndGroupDescriptionResolver.resolveDescription(
                 new Constraint(enumName, singletonMap(VALUE, (Object) value)));
 
         // fallback
         if (isBlank(message) || message.equals(enumName)) {
-            message = translate("constraints-enum", value);
+            message = translationResolver.translate("constraints-enum", value);
         }
         return singletonList(message);
     }

spring-auto-restdocs-core/src/main/java/capital/scalable/restdocs/i18n/ResourceBundleSnippetTranslationResolver.java

@@ -0,0 +1,72 @@
+/*-
+ * #%L
+ * Spring Auto REST Docs Core
+ * %%
+ * Copyright (C) 2015 - 2019 Scalable Capital GmbH
+ * %%
+ * 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
+ *
+ *      http://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.
+ * #L%
+ */
+package capital.scalable.restdocs.i18n;
+
+import java.text.MessageFormat;
+import java.util.Locale;
+import java.util.MissingResourceException;
+import java.util.ResourceBundle;
+
+/**
+ * Inspired by
+ * {@link org.springframework.restdocs.constraints.ResourceBundleConstraintDescriptionResolver}
+ */
+public class ResourceBundleSnippetTranslationResolver implements SnippetTranslationResolver {
+
+    private ResourceBundle defaultMessages;
+
+    private ResourceBundle userMessages;
+
+    public ResourceBundleSnippetTranslationResolver() {
+        defaultMessages = getBundle("DefaultSnippetMessages");
+        userMessages = getBundle("SnippetMessages");
+    }
+
+    private static ResourceBundle getBundle(String name) {
+        try {
+            return ResourceBundle.getBundle(
+                    ResourceBundleSnippetTranslationResolver.class.getPackage()
+                            .getName() + "." + name,
+                    Locale.getDefault(), Thread.currentThread().getContextClassLoader());
+        } catch (MissingResourceException ex) {
+            return null;
+        }
+    }
+
+    public String translate(String key, Object... args) {
+        try {
+            if (userMessages != null) {
+                return format(userMessages.getString(key), args);
+            }
+        } catch (MissingResourceException ex) {
+            // Continue and return default description, if available
+        }
+        return format(defaultMessages.getString(key), args);
+    }
+
+    // visible for testing
+    void setUserMessages(String name) {
+        userMessages = getBundle(name);
+    }
+
+    private static String format(String message, Object[] args) {
+        return new MessageFormat(message).format(args);
+    }
+}

spring-auto-restdocs-core/src/main/java/capital/scalable/restdocs/i18n/SnippetTranslationManager.java

@@ -0,0 +1,14 @@
+package capital.scalable.restdocs.i18n;
+
+
+public class SnippetTranslationManager {
+
+    private static SnippetTranslationResolver snippetTranslationResolver;
+
+    public static synchronized SnippetTranslationResolver getDefaultResolver() {
+        if (snippetTranslationResolver == null) {
+            snippetTranslationResolver = new ResourceBundleSnippetTranslationResolver();
+        }
+        return snippetTranslationResolver;
+    }
+}

spring-auto-restdocs-core/src/main/java/capital/scalable/restdocs/i18n/SnippetTranslationResolver.java

@@ -1,67 +1,6 @@
-/*-
- * #%L
- * Spring Auto REST Docs Core
- * %%
- * Copyright (C) 2015 - 2019 Scalable Capital GmbH
- * %%
- * 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
- *
- *      http://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.
- * #L%
- */
 package capital.scalable.restdocs.i18n;
 
-import java.text.MessageFormat;
-import java.util.Locale;
-import java.util.MissingResourceException;
-import java.util.ResourceBundle;
+public interface SnippetTranslationResolver {
 
-/**
- * Inspired by
- * {@link org.springframework.restdocs.constraints.ResourceBundleConstraintDescriptionResolver}
- */
-public class SnippetTranslationResolver {
-
-    private static ResourceBundle defaultMessages = getBundle("DefaultSnippetMessages");
-
-    private static ResourceBundle userMessages = getBundle("SnippetMessages");
-
-    private static ResourceBundle getBundle(String name) {
-        try {
-            return ResourceBundle.getBundle(
-                    SnippetTranslationResolver.class.getPackage()
-                            .getName() + "." + name,
-                    Locale.getDefault(), Thread.currentThread().getContextClassLoader());
-        } catch (MissingResourceException ex) {
-            return null;
-        }
-    }
-
-    public static String translate(String key, Object... args) {
-        try {
-            if (userMessages != null) {
-                return format(userMessages.getString(key), args);
-            }
-        } catch (MissingResourceException ex) {
-            // Continue and return default description, if available
-        }
-        return format(defaultMessages.getString(key), args);
-    }
-
-    // visible for testing
-    static void setUserMessages(String name) {
-        userMessages = getBundle(name);
-    }
-
-    private static String format(String message, Object[] args) {
-        return new MessageFormat(message).format(args);
-    }
+    String translate(String key, Object... args);
 }

spring-auto-restdocs-core/src/main/java/capital/scalable/restdocs/i18n/TranslationHandlers.java

@@ -0,0 +1,31 @@
+package capital.scalable.restdocs.i18n;
+
+import org.springframework.test.web.servlet.MvcResult;
+import org.springframework.test.web.servlet.ResultHandler;
+
+import static capital.scalable.restdocs.OperationAttributeHelper.setTranslationResolver;
+
+public abstract class TranslationHandlers {
+
+    public static ResultHandler defaultTranslation() {
+        return new TranslationPreparingResultHandler(SnippetTranslationManager.getDefaultResolver());
+    }
+
+    public static ResultHandler translation(SnippetTranslationResolver translationResolver) {
+        return new TranslationPreparingResultHandler(translationResolver);
+    }
+
+    private static class TranslationPreparingResultHandler implements ResultHandler {
+
+        private final SnippetTranslationResolver translationResolver;
+
+        public TranslationPreparingResultHandler(SnippetTranslationResolver translationResolver) {
+            this.translationResolver = translationResolver;
+        }
+
+        @Override
+        public void handle(MvcResult mvcResult) throws Exception {
+            setTranslationResolver(mvcResult.getRequest(), translationResolver);
+        }
+    }
+}