DS.JSONSerializer Class packages/ember-data/lib/serializers/json_serializer.js:11

The extract method is used to deserialize payload data from the server. By default the JSONSerializer does not push the records into the store. However records that subclass JSONSerializer such as the RESTSerializer may push records into the store as part of the extract call.

This method deletegates to a more specific extract method based on the requestType.

Example

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var get = Ember.get;
socket.on('message', function(message) {
  var modelName = message.model;
  var data = message.data;
  var type = store.modelFor(modelName);
  var serializer = store.serializerFor(type.typeKey);
  var record = serializer.extract(store, type, data, get(data, 'id'), 'single');
  store.push(modelName, record);
});

extractArray is used to deserialize an array of records returned from the adapter.

Example

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App.PostSerializer = DS.JSONSerializer.extend({
  extractArray: function(store, type, payload) {
    return payload.map(function(json) {
      return this.extractSingle(json);
    }, this);
  }
});

extractCreateRecord is a hook into the extract method used when a call is made to DS.Store#createRecord. By default this method is alias for extractSave.

extractDeleteRecord is a hook into the extract method used when a call is made to DS.Store#deleteRecord. By default this method is alias for extractSave.

extractFind is a hook into the extract method used when a call is made to DS.Store#find. By default this method is alias for extractSingle.

extractFindAll is a hook into the extract method used when a call is made to DS.Store#findAll. By default this method is an alias for extractArray.

extractFindBelongsTo is a hook into the extract method used when a call is made to DS.Store#findBelongsTo. By default this method is alias for extractSingle.

extractFindHasMany is a hook into the extract method used when a call is made to DS.Store#findHasMany. By default this method is alias for extractArray.

extractFindMany is a hook into the extract method used when a call is made to DS.Store#findMany. By default this method is alias for extractArray.

extractFindQuery is a hook into the extract method used when a call is made to DS.Store#findQuery. By default this method is an alias for extractArray.

extractMeta is used to deserialize any meta information in the adapter payload. By default Ember Data expects meta information to be located on the meta property of the payload object.

Example

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App.PostSerializer = DS.JSONSerializer.extend({
  extractMeta: function(store, type, payload) {
    if (payload && payload._pagination) {
      store.metaForType(type, payload._pagination);
      delete payload._pagination;
    }
  }
});

extractSave is a hook into the extract method used when a call is made to DS.Model#save. By default this method is alias for extractSingle.

extractSingle is used to deserialize a single record returned from the adapter.

Example

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App.PostSerializer = DS.JSONSerializer.extend({
  extractSingle: function(store, type, payload) {
    payload.comments = payload._embedded.comment;
    delete payload._embedded;

    return this._super(store, type, payload);
  },
});

extractUpdateRecord is a hook into the extract method used when a call is made to DS.Store#update. By default this method is alias for extractSave.

keyForRelationship can be used to define a custom key when serializeing relationship properties. By default JSONSerializer does not provide an implementation of this method.

Example

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 App.PostSerializer = DS.JSONSerializer.extend({
   keyForRelationship: function(key, relationship) {
      return 'rel_' + Ember.String.underscore(key);
   }
 });

Normalizes a part of the JSON payload returned by the server. You should override this method, munge the hash and call super if you have generic normalization to do.

It takes the type of the record that is being normalized (as a DS.Model class), the property where the hash was originally found, and the hash to normalize.

You can use this method, for example, to normalize underscored keys to camelized or other general-purpose normalizations.

Example

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App.ApplicationSerializer = DS.JSONSerializer.extend({
  normalize: function(type, hash) {
    var normalizedHash = {};
    var fields = Ember.get(type, 'fields');
    fields.forEach(function(field) {
      var normalizedProp = Ember.String.camelize(field);
      normalizedHash[normalizedProp] = hash[field];
    });
    return this._super.apply(this, arguments);
  }
});

Called when a record is saved in order to convert the record into JSON.

By default, it creates a JSON object with a key for each attribute and belongsTo relationship.

For example, consider this model:

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App.Comment = DS.Model.extend({
  title: DS.attr(),
  body: DS.attr(),

  author: DS.belongsTo('user')
});

The default serialization would create a JSON object like:

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{
  "title": "Rails is unagi",
  "body": "Rails? Omakase? O_O",
  "author": 12
}

By default, attributes are passed through as-is, unless you specified an attribute type (DS.attr('date')). If you specify a transform, the JavaScript value will be serialized when inserted into the JSON hash.

By default, belongs-to relationships are converted into IDs when inserted into the JSON hash.

IDs

serialize takes an options hash with a single option: includeId. If this option is true, serialize will, by default include the ID in the JSON object it builds.

The adapter passes in includeId: true when serializing a record for createRecord, but not for updateRecord.

Customization

Your server may expect a different JSON format than the built-in serialization format.

In that case, you can implement serialize yourself and return a JSON hash of your choosing.

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App.PostSerializer = DS.JSONSerializer.extend({
  serialize: function(post, options) {
    var json = {
      POST_TTL: post.get('title'),
      POST_BDY: post.get('body'),
      POST_CMS: post.get('comments').mapProperty('id')
    }

    if (options.includeId) {
      json.POST_ID_ = post.get('id');
    }

    return json;
  }
});

Customizing an App-Wide Serializer

If you want to define a serializer for your entire application, you'll probably want to use eachAttribute and eachRelationship on the record.

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App.ApplicationSerializer = DS.JSONSerializer.extend({
  serialize: function(record, options) {
    var json = {};

    record.eachAttribute(function(name) {
      json[serverAttributeName(name)] = record.get(name);
    })

    record.eachRelationship(function(name, relationship) {
      if (relationship.kind === 'hasMany') {
        json[serverHasManyName(name)] = record.get(name).mapBy('id');
      }
    });

    if (options.includeId) {
      json.ID_ = record.get('id');
    }

    return json;
  }
});

function serverAttributeName(attribute) {
  return attribute.underscore().toUpperCase();
}

function serverHasManyName(name) {
  return serverAttributeName(name.singularize()) + "_IDS";
}

This serializer will generate JSON that looks like this:

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{
  "TITLE": "Rails is omakase",
  "BODY": "Yep. Omakase.",
  "COMMENT_IDS": [ 1, 2, 3 ]
}

Tweaking the Default JSON

If you just want to do some small tweaks on the default JSON, you can call super first and make the tweaks on the returned JSON.

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App.PostSerializer = DS.JSONSerializer.extend({
  serialize: function(record, options) {
    var json = this._super.apply(this, arguments);

    json.subject = json.title;
    delete json.title;

    return json;
  }
});

serializeAttribute can be used to customize how DS.attr properties are serialized

For example if you wanted to ensure all you attributes were always serialized as properties on an attributes object you could write:

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App.ApplicationSerializer = DS.JSONSerializer.extend({
  serializeAttribute: function(record, json, key, attributes) {
    json.attributes = json.attributes || {};
    this._super(record, json.attributes, key, attributes);
  }
});

serializeBelongsTo can be used to customize how DS.belongsTo properties are serialized.

Example

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App.PostSerializer = DS.JSONSerializer.extend({
  serializeBelongsTo: function(record, json, relationship) {
    var key = relationship.key;

    var belongsTo = get(record, key);

    key = this.keyForRelationship ? this.keyForRelationship(key, "belongsTo") : key;

    json[key] = Ember.isNone(belongsTo) ? belongsTo : belongsTo.toJSON();
  }
});

serializeHasMany can be used to customize how DS.hasMany properties are serialized.

Example

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App.PostSerializer = DS.JSONSerializer.extend({
  serializeHasMany: function(record, json, relationship) {
    var key = relationship.key;
    if (key === 'comments') {
      return;
    } else {
      this._super.apply(this, arguments);
    }
  }
});

You can use this method to customize how polymorphic objects are serialized. Objects are considered to be polymorphic if {polymorphic: true} is pass as the second argument to the DS.belongsTo function.

Example

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App.CommentSerializer = DS.JSONSerializer.extend({
  serializePolymorphicType: function(record, json, relationship) {
    var key = relationship.key,
        belongsTo = get(record, key);
    key = this.keyForAttribute ? this.keyForAttribute(key) : key;
    json[key + "_type"] = belongsTo.constructor.typeKey;
  }
});