Add new GraphQLJson type to the CustomTypeValue

Current implementation allows Map to be serialized as JSON string value, with this changes we introduce new CustomTypeValue type that will
allow Map to be serialized as regular JSON object.

Closes apollographql#873

Author: sav007

apollo-api/src/main/java/com/apollographql/apollo/api/InputFieldWriter.java

@@ -1,6 +1,7 @@
 package com.apollographql.apollo.api;
 
 import java.io.IOException;
+import java.util.Map;
 
 import javax.annotation.Nonnull;
 
@@ -23,6 +24,8 @@ public interface InputFieldWriter {
 
   void writeList(@Nonnull String fieldName, ListWriter listWriter) throws IOException;
 
+  void writeMap(@Nonnull String fieldName, Map<String, Object> value) throws IOException;
+
   interface ListWriter {
     void write(@Nonnull ListItemWriter listItemWriter) throws IOException;
   }
@@ -45,5 +48,7 @@ interface ListItemWriter {
     void writeObject(InputFieldMarshaller marshaller) throws IOException;
 
     void writeList(ListWriter listWriter) throws IOException;
+
+    void writeMap(Map<String, Object> value) throws IOException;
   }
 }

apollo-runtime/src/main/java/com/apollographql/apollo/internal/json/InputFieldJsonWriter.java

@@ -8,10 +8,12 @@
 import com.apollographql.apollo.response.ScalarTypeAdapters;
 
 import java.io.IOException;
+import java.util.Map;
 
 import javax.annotation.Nonnull;
 
 import static com.apollographql.apollo.api.internal.Utils.checkNotNull;
+import static com.apollographql.apollo.internal.json.Utils.writeToJson;
 
 public class InputFieldJsonWriter implements InputFieldWriter {
   private final JsonWriter jsonWriter;
@@ -90,6 +92,8 @@ public InputFieldJsonWriter(JsonWriter jsonWriter, ScalarTypeAdapters scalarType
         writeNumber(fieldName, ((CustomTypeValue.GraphQLNumber) customTypeValue).value);
       } else if (customTypeValue instanceof CustomTypeValue.GraphQLJsonString) {
         writeString(fieldName, ((CustomTypeValue.GraphQLJsonString) customTypeValue).value);
+      } else if (customTypeValue instanceof CustomTypeValue.GraphQLJson) {
+        writeMap(fieldName, ((CustomTypeValue.GraphQLJson) customTypeValue).value);
       } else {
         throw new IllegalArgumentException("Unsupported custom value type: " + customTypeValue);
       }
@@ -120,6 +124,16 @@ public InputFieldJsonWriter(JsonWriter jsonWriter, ScalarTypeAdapters scalarType
     }
   }
 
+  @Override public void writeMap(@Nonnull String fieldName, Map<String, Object> value) throws IOException {
+    checkNotNull(fieldName, "fieldName == null");
+    if (value == null) {
+      jsonWriter.name(fieldName).nullValue();
+    } else {
+      jsonWriter.name(fieldName);
+      writeToJson(value, jsonWriter);
+    }
+  }
+
   private static final class JsonListItemWriter implements ListItemWriter {
     private final JsonWriter jsonWriter;
     private final ScalarTypeAdapters scalarTypeAdapters;
@@ -177,6 +191,10 @@ private static final class JsonListItemWriter implements ListItemWriter {
       }
     }
 
+    @Override public void writeMap(Map<String, Object> value) throws IOException {
+      writeToJson(value, jsonWriter);
+    }
+
     @SuppressWarnings("unchecked")
     @Override public void writeCustom(ScalarType scalarType, Object value) throws IOException {
       if (value == null) {
@@ -192,6 +210,8 @@ private static final class JsonListItemWriter implements ListItemWriter {
           writeNumber(((CustomTypeValue.GraphQLNumber) customTypeValue).value);
         } else if (customTypeValue instanceof CustomTypeValue.GraphQLJsonString) {
           writeString(((CustomTypeValue.GraphQLJsonString) customTypeValue).value);
+        } else if (customTypeValue instanceof CustomTypeValue.GraphQLJson) {
+          writeMap(((CustomTypeValue.GraphQLJson) customTypeValue).value);
         } else {
           throw new IllegalArgumentException("Unsupported custom value type: " + customTypeValue);
         }

apollo-runtime/src/main/java/com/apollographql/apollo/internal/json/Utils.java

@@ -29,8 +29,8 @@ public static void writeToJson(Object value, JsonWriter jsonWriter) throws IOExc
       jsonWriter.nullValue();
     } else if (value instanceof Map) {
       jsonWriter.beginObject();
-      for (Map.Entry<String, Object> entry : ((Map<String, Object>) value).entrySet()) {
-        String key = entry.getKey();
+      for (Map.Entry<Object, Object> entry : ((Map<Object, Object>) value).entrySet()) {
+        String key = entry.getKey().toString();
         jsonWriter.name(key);
         writeToJson(entry.getValue(), jsonWriter);
       }

apollo-runtime/src/main/java/com/apollographql/apollo/response/CustomTypeAdapter.java

@@ -3,60 +3,45 @@
 import javax.annotation.Nonnull;
 
 /**
- * CustomTypeAdapter class represents the adapter for converting GraphQL custom scalar types to Java objects.
+ * Class represents the adapter for mapping GraphQL custom scalar types to Java objects.
  *
  * <h3>Defining a custom scalar type adapter</h3>
  *
  * The GraphQL specification includes the following default scalar types: <b>String, Int, Float and Boolean</b>. But
  * often use cases arise when support for custom scalar types is required and for those cases this class should be used
  * to customize conversion. Here's an example of a type adapter for scalar type {@link java.util.Date}:
- * <pre>
- *   {@code
+ * <pre>{@code
+ * CustomTypeAdapter<Date> dateCustomTypeAdapter = new CustomTypeAdapter<Date>() {
  *
- *  CustomTypeAdapter<Date> dateCustomTypeAdapter = new CustomTypeAdapter<Date>() {
- *                @Override
- *                public Date decode(String value) {
- *                  try {
- *                    return ISO8601_DATE_FORMAT.parse(value);
- *                  } catch (ParseException e) {
- *                    throw new RuntimeException(e);
- *                  }
- *                }
- *                @Override
- *                public String encode(Date value) {
- *                  return ISO8601_DATE_FORMAT.format(value);
- *                }
- *          };
- * }
- * </pre>
- * To use a custom type adapter with Apollo, you must first define the mapping in the build.gradle file:
- * <pre>   {@code
- *  apollo {
- *        customTypeMapping {
- *        DateTime = "java.util.Date"
- *        }
+ *    public Date decode(CustomTypeValue value) {
+ *      try {
+ *        return ISO8601_DATE_FORMAT.parse(value);
+ *      } catch (ParseException e) {
+ *        throw new RuntimeException(e);
  *      }
+ *    }
+ *
+ *    public CustomTypeValue encode(Date value) {
+ *      return ISO8601_DATE_FORMAT.format(value);
+ *    }
+ * };
  * }
  * </pre>
- *
- * Sometimes when the name of the custom scalar type is a reserved keyword in groovy, you can instead use it's Map
- * notation. For example, in order to use the reserved keyword URL, define the mapping like this:
- * <pre>   {@code
+ * To use a custom type adapter with Apollo, you must first define the mapping in the build.gradle file:
+ * <pre>{@code
  * apollo {
- *        customTypeMapping['URL'] = "String"
- *    }
+ *  customTypeMapping['DateTime'] = "java.util.Date"
+ * }
  * }
  * </pre>
+ *
  * The lines above tell the compiler which type to use while generating the classes. Once this is done, register the
  * type adapter with {@link com.apollographql.apollo.ApolloClient.Builder}:
- * <pre>
- *   {@code
- *           ApolloClient.Builder builder = ApolloClient.builder()
- *                                    .addCustomTypeAdapter(CustomType.DATE, dateCustomTypeAdapter);
- *                ApolloClient client = builder.client;
+ * <pre>{@code
+ * ApolloClient.Builder builder = ApolloClient.builder()
+ *  .addCustomTypeAdapter(CustomType.DATE, dateCustomTypeAdapter);
  * }
  * </pre>
- *
  * In the example code above, the CustomType.DATE is the class generated by the compiler.
  */
 public interface CustomTypeAdapter<T> {

apollo-runtime/src/main/java/com/apollographql/apollo/response/CustomTypeValue.java

@@ -22,10 +22,10 @@ public static CustomTypeValue fromRawValue(Object value) {
       } catch (Exception e) {
         throw new RuntimeException(e);
       }
-    } else if (value instanceof java.lang.Boolean) {
-      return new GraphQLBoolean((java.lang.Boolean) value);
-    } else if (value instanceof java.lang.Number) {
-      return new GraphQLNumber((java.lang.Number) value);
+    } else if (value instanceof Boolean) {
+      return new GraphQLBoolean((Boolean) value);
+    } else if (value instanceof Number) {
+      return new GraphQLNumber((Number) value);
     } else {
       return new GraphQLString(value.toString());
     }
@@ -38,35 +38,44 @@ private CustomTypeValue(T value) {
   /**
    * Represents a {@code String} value
    */
-  public static class GraphQLString extends CustomTypeValue<java.lang.String> {
-    public GraphQLString(java.lang.String value) {
+  public static class GraphQLString extends CustomTypeValue<String> {
+    public GraphQLString(String value) {
       super(value);
     }
   }
 
   /**
    * Represents a {@code Boolean} value
    */
-  public static class GraphQLBoolean extends CustomTypeValue<java.lang.Boolean> {
-    public GraphQLBoolean(java.lang.Boolean value) {
+  public static class GraphQLBoolean extends CustomTypeValue<Boolean> {
+    public GraphQLBoolean(Boolean value) {
       super(value);
     }
   }
 
   /**
    * Represents a {@code Number} value
    */
-  public static class GraphQLNumber extends CustomTypeValue<java.lang.Number> {
-    public GraphQLNumber(java.lang.Number value) {
+  public static class GraphQLNumber extends CustomTypeValue<Number> {
+    public GraphQLNumber(Number value) {
       super(value);
     }
   }
 
   /**
    * Represents a {@code JsonString} value
    */
-  public static class GraphQLJsonString extends CustomTypeValue<java.lang.String> {
-    public GraphQLJsonString(java.lang.String value) {
+  public static class GraphQLJsonString extends CustomTypeValue<String> {
+    public GraphQLJsonString(String value) {
+      super(value);
+    }
+  }
+
+  /**
+   * Represents a JSON object value, will serialized as an regular json object
+   */
+  public static class GraphQLJson extends CustomTypeValue<Map<String, Object>> {
+    public GraphQLJson(Map<String, Object> value) {
       super(value);
     }
   }