Add a CacheBuilderSpecSerializer so that a default value can be used …

…in configurations (#1551)
dropwizard · May 21, 2016 · a8ac50c · a8ac50c
1 parent d95b859
commit a8ac50c
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Showing 3 changed files with 48 additions and 0 deletions.
diff --git a/...ard-configuration/src/test/java/io/dropwizard/configuration/ConfigurationFactoryTest.java b/...ard-configuration/src/test/java/io/dropwizard/configuration/ConfigurationFactoryTest.java
@@ -1,6 +1,7 @@
 package io.dropwizard.configuration;
 
 import com.fasterxml.jackson.annotation.JsonProperty;
+import com.google.common.cache.CacheBuilderSpec;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.io.Resources;
@@ -12,6 +13,7 @@
 import org.junit.Before;
 import org.junit.Test;
 
+import javax.validation.Valid;
 import javax.validation.Validator;
 import javax.validation.constraints.NotNull;
 import javax.validation.constraints.Pattern;
@@ -111,6 +113,10 @@ static class ExampleWithDefaults {
         @JsonProperty
         List<ExampleServer> servers = ImmutableList.of(
                 ExampleServer.create(8080), ExampleServer.create(8081), ExampleServer.create(8082));
+
+        @JsonProperty
+        @Valid
+        CacheBuilderSpec cacheBuilderSpec = CacheBuilderSpec.disableCaching();
     }
 
     static class NonInsatiableExample {
@@ -153,6 +159,17 @@ public void setUp() throws Exception {
         this.validFile = resourceFileName("factory-test-valid.yml");
     }
 
+    @Test
+    public void usesDefaultedCacheBuilderSpec() throws Exception {
+        final ExampleWithDefaults example =
+            new YamlConfigurationFactory<>(ExampleWithDefaults.class, validator, Jackson.newObjectMapper(), "dw")
+                .build();
+        assertThat(example.cacheBuilderSpec)
+            .isNotNull();
+        assertThat(example.cacheBuilderSpec)
+            .isEqualTo(CacheBuilderSpec.disableCaching());
+    }
+
     @Test
     public void loadsValidConfigFiles() throws Exception {
         final Example example = factory.build(validFile);

diff --git a/dropwizard-jackson/src/main/java/io/dropwizard/jackson/GuavaExtrasModule.java b/dropwizard-jackson/src/main/java/io/dropwizard/jackson/GuavaExtrasModule.java
@@ -1,15 +1,21 @@
 package io.dropwizard.jackson;
 
+import com.fasterxml.jackson.core.JsonGenerator;
 import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.core.Version;
 import com.fasterxml.jackson.databind.BeanDescription;
 import com.fasterxml.jackson.databind.DeserializationContext;
 import com.fasterxml.jackson.databind.DeserializationConfig;
 import com.fasterxml.jackson.databind.JavaType;
 import com.fasterxml.jackson.databind.JsonDeserializer;
 import com.fasterxml.jackson.databind.JsonMappingException;
+import com.fasterxml.jackson.databind.JsonSerializer;
 import com.fasterxml.jackson.databind.Module;
+import com.fasterxml.jackson.databind.SerializationConfig;
+import com.fasterxml.jackson.databind.SerializerProvider;
 import com.fasterxml.jackson.databind.deser.Deserializers;
+import com.fasterxml.jackson.databind.ser.Serializers;
 import com.google.common.cache.CacheBuilderSpec;
 
 import java.io.IOException;
@@ -27,6 +33,13 @@ public CacheBuilderSpec deserialize(JsonParser jp,
         }
     }
 
+    private static class CacheBuilderSpecSerializer extends JsonSerializer<CacheBuilderSpec> {
+        @Override
+        public void serialize(CacheBuilderSpec value, JsonGenerator gen, SerializerProvider serializers) throws IOException, JsonProcessingException {
+            gen.writeString(value.toParsableString());
+        }
+    }
+
     private static class GuavaExtrasDeserializers extends Deserializers.Base {
         @Override
         public JsonDeserializer<?> findBeanDeserializer(JavaType type,
@@ -40,6 +53,17 @@ public JsonDeserializer<?> findBeanDeserializer(JavaType type,
         }
     }
 
+    private static class GuavaExtrasSerializers extends Serializers.Base {
+        @Override
+        public JsonSerializer<?> findSerializer(SerializationConfig config, JavaType type, BeanDescription beanDesc) {
+            if (CacheBuilderSpec.class.isAssignableFrom(type.getRawClass())) {
+                return new CacheBuilderSpecSerializer();
+            }
+
+            return super.findSerializer(config, type, beanDesc);
+        }
+    }
+
     @Override
     public String getModuleName() {
         return "guava-extras";
@@ -53,5 +77,6 @@ public Version version() {
     @Override
     public void setupModule(SetupContext context) {
         context.addDeserializers(new GuavaExtrasDeserializers());
+        context.addSerializers(new GuavaExtrasSerializers());
     }
 }
diff --git a/dropwizard-jackson/src/test/java/io/dropwizard/jackson/GuavaExtrasModuleTest.java b/dropwizard-jackson/src/test/java/io/dropwizard/jackson/GuavaExtrasModuleTest.java
@@ -31,6 +31,12 @@ public void canDeserializeCacheBuilderSpecs() throws Exception {
                 .isEqualTo(CacheBuilderSpec.parse("maximumSize=30"));
     }
 
+    @Test
+    public void canSerializeCacheBuilderSpecs() throws Exception {
+        assertThat(mapper.writeValueAsString(CacheBuilderSpec.disableCaching()))
+            .isEqualTo("\"maximumSize=0\"");
+    }
+
     @Test
     public void canDeserializeAbsentOptions() throws Exception {
         assertThat(mapper.readValue("null", Optional.class))