Class DS.JSONSerializer

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 delegates to a more specific extract method based on the requestType.

To override this method with a custom one, make sure to call return this._super(store, type, payload, id, requestType) with your pre-processed data.

Here's an example of using extract manually:

socket.on('message', function(message) {
  var data = message.data;
  var typeClass = store.modelFor(message.modelName);
  var serializer = store.serializerFor(typeClass.modelName);
  var record = serializer.extract(store, typeClass, data, data.id, 'single');

  store.push(message.modelName, record);
});

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

Example

import DS from 'ember-data';

export default DS.JSONSerializer.extend({
  extractArray: function(store, typeClass, payload) {
    return payload.map(function(json) {
      return this.extractSingle(store, typeClass, json);
    }, this);
  }
});

Returns the resource's attributes formatted as a JSON-API "attributes object".

http://jsonapi.org/format/#document-resource-object-attributes

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

extractDeleteRecord is a hook into the extract method used when a call is made to DS.Model#save and the record has been deleted. By default this method is alias for extractSave.

extractErrors is used to extract model errors when a call is made to DS.Model#save which fails with an InvalidError. By default Ember Data expects error information to be located on the errors property of the payload object.

Example

import DS from 'ember-data';

export default DS.JSONSerializer.extend({
  extractErrors: function(store, typeClass, payload, id) {
    if (payload && typeof payload === 'object' && payload._problems) {
      payload = payload._problems;
      this.normalizeErrors(typeClass, payload);
    }
    return payload;
  }
});

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.

Returns the resource's ID.

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

import DS from 'ember-data';

export default DS.JSONSerializer.extend({
  extractMeta: function(store, typeClass, payload) {
    if (payload && payload._pagination) {
      store.setMetadataFor(typeClass, payload._pagination);
      delete payload._pagination;
    }
  }
});

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

Returns a relationship formatted as a JSON-API "relationship object".

http://jsonapi.org/format/#document-resource-object-relationships

Returns the resource's relationships formatted as a JSON-API "relationships object".

http://jsonapi.org/format/#document-resource-object-relationships

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

import DS from 'ember-data';

export default DS.JSONSerializer.extend({
  extractSingle: function(store, typeClass, payload) {
    payload.comments = payload._embedded.comment;
    delete payload._embedded;

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

extractUpdateRecord is a hook into the extract method used when a call is made to DS.Model#save and the record has been updated. By default this method is alias for extractSave.

keyForAttribute can be used to define rules for how to convert an attribute name in your model to a key in your JSON.

Example

import DS from 'ember-data';

export default DS.RESTSerializer.extend({
  keyForAttribute: function(attr, method) {
    return Ember.String.underscore(attr).toUpperCase();
  }
});

keyForLink can be used to define a custom key when deserializing link properties.

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

Example

 import DS from 'ember-data';

 export default DS.JSONSerializer.extend({
   keyForRelationship: function(key, relationship, method) {
     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

import DS from 'ember-data';

export default DS.JSONSerializer.extend({
  normalize: function(typeClass, hash) {
    var fields = Ember.get(typeClass, 'fields');
    fields.forEach(function(field) {
      var payloadField = Ember.String.underscore(field);
      if (field === payloadField) { return; }

      hash[field] = hash[payloadField];
      delete hash[payloadField];
    });
    return this._super.apply(this, arguments);
  }
});

The normalizeResponse method is used to normalize a payload from the server to a JSON-API Document.

http://jsonapi.org/format/#document-structure

This method delegates to a more specific normalize method based on the requestType.

To override this method with a custom one, make sure to call return this._super(store, primaryModelClass, payload, id, requestType) with your pre-processed data.

Here's an example of using normalizeResponse manually:

socket.on('message', function(message) {
  var data = message.data;
  var modelClass = store.modelFor(data.modelName);
  var serializer = store.serializerFor(data.modelName);
  var json = serializer.normalizeSingleResponse(store, modelClass, data, data.id);

  store.push(normalized);
});

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:

import DS from 'ember-data';

export default DS.Model.extend({
  title: DS.attr(),
  body: DS.attr(),

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

The default serialization would create a JSON object like:

{
  "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.

import DS from 'ember-data';

export default DS.JSONSerializer.extend({
  serialize: function(snapshot, options) {
    var json = {
      POST_TTL: snapshot.attr('title'),
      POST_BDY: snapshot.attr('body'),
      POST_CMS: snapshot.hasMany('comments', { ids: true })
    }

    if (options.includeId) {
      json.POST_ID_ = snapshot.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.

import DS from 'ember-data';

export default DS.JSONSerializer.extend({
  serialize: function(snapshot, options) {
    var json = {};

    snapshot.eachAttribute(function(name) {
      json[serverAttributeName(name)] = snapshot.attr(name);
    })

    snapshot.eachRelationship(function(name, relationship) {
      if (relationship.kind === 'hasMany') {
        json[serverHasManyName(name)] = snapshot.hasMany(name, { ids: true });
      }
    });

    if (options.includeId) {
      json.ID_ = snapshot.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:

{
  "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.

import DS from 'ember-data';

export default DS.JSONSerializer.extend({
  serialize: function(snapshot, 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 your attributes were always serialized as properties on an attributes object you could write:

import DS from 'ember-data';

export default DS.JSONSerializer.extend({
  serializeAttribute: function(snapshot, json, key, attributes) {
    json.attributes = json.attributes || {};
    this._super(snapshot, json.attributes, key, attributes);
  }
});

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

Example

import DS from 'ember-data';

export default DS.JSONSerializer.extend({
  serializeBelongsTo: function(snapshot, json, relationship) {
    var key = relationship.key;

    var belongsTo = snapshot.belongsTo(key);

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

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

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

Example

import DS from 'ember-data';

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

You can use this method to customize how a serialized record is added to the complete JSON hash to be sent to the server. By default the JSON Serializer does not namespace the payload and just sends the raw serialized JSON object. If your server expects namespaced keys, you should consider using the RESTSerializer. Otherwise you can override this method to customize how the record is added to the hash.

For example, your server may expect underscored root objects.

import DS from 'ember-data';

export default DS.RESTSerializer.extend({
  serializeIntoHash: function(data, type, snapshot, options) {
    var root = Ember.String.decamelize(type.modelName);
    data[root] = this.serialize(snapshot, options);
  }
});

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

import DS from 'ember-data';

export default DS.JSONSerializer.extend({
  serializePolymorphicType: function(snapshot, json, relationship) {
    var key = relationship.key,
        belongsTo = snapshot.belongsTo(key);
    key = this.keyForAttribute ? this.keyForAttribute(key, "serialize") : key;

    if (Ember.isNone(belongsTo)) {
      json[key + "_type"] = null;
    } else {
      json[key + "_type"] = belongsTo.modelName;
    }
  }
});