/** @module ember-data */ import { typeOf, isNone } from '@ember/utils'; import { makeArray } from '@ember/array'; import { camelize } from '@ember/string'; import { singularize } from "ember-inflector"; import { assert, deprecate, warn } from '@ember/debug'; import { DEBUG } from '@glimmer/env'; import JSONSerializer from "../serializers/json"; import { coerceId, modelHasAttributeOrRelationshipNamedType, normalizeModelName, isEnabled } from '../-private'; /** Normally, applications will use the `RESTSerializer` by implementing the `normalize` method. This allows you to do whatever kind of munging you need, and is especially useful if your server is inconsistent and you need to do munging differently for many different kinds of responses. See the `normalize` documentation for more information. ## Across the Board Normalization There are also a number of hooks that you might find useful to define across-the-board rules for your payload. These rules will be useful if your server is consistent, or if you're building an adapter for an infrastructure service, like Firebase, and want to encode service conventions. For example, if all of your keys are underscored and all-caps, but otherwise consistent with the names you use in your models, you can implement across-the-board rules for how to convert an attribute name in your model to a key in your JSON. ```app/serializers/application.js import DS from 'ember-data'; import { underscore } from '@ember/string'; export default DS.RESTSerializer.extend({ keyForAttribute(attr, method) { return underscore(attr).toUpperCase(); } }); ``` You can also implement `keyForRelationship`, which takes the name of the relationship as the first parameter, the kind of relationship (`hasMany` or `belongsTo`) as the second parameter, and the method (`serialize` or `deserialize`) as the third parameter. @class RESTSerializer @namespace DS @extends DS.JSONSerializer */ const RESTSerializer = JSONSerializer.extend({ /** `keyForPolymorphicType` can be used to define a custom key when serializing and deserializing a polymorphic type. By default, the returned key is `${key}Type`. Example ```app/serializers/post.js import DS from 'ember-data'; export default DS.RESTSerializer.extend({ keyForPolymorphicType(key, relationship) { var relationshipKey = this.keyForRelationship(key); return 'type-' + relationshipKey; } }); ``` @method keyForPolymorphicType @param {String} key @param {String} typeClass @param {String} method @return {String} normalized key */ keyForPolymorphicType(key, typeClass, method) { let relationshipKey = this.keyForRelationship(key); return `${relationshipKey}Type`; }, /** 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. For example, if you have a payload that looks like this: ```js { "post": { "id": 1, "title": "Rails is omakase", "comments": [ 1, 2 ] }, "comments": [{ "id": 1, "body": "FIRST" }, { "id": 2, "body": "Rails is unagi" }] } ``` The `normalize` method will be called three times: * With `App.Post`, `"posts"` and `{ id: 1, title: "Rails is omakase", ... }` * With `App.Comment`, `"comments"` and `{ id: 1, body: "FIRST" }` * With `App.Comment`, `"comments"` and `{ id: 2, body: "Rails is unagi" }` You can use this method, for example, to normalize underscored keys to camelized or other general-purpose normalizations. You will only need to implement `normalize` and manipulate the payload as desired. For example, if the `IDs` under `"comments"` are provided as `_id` instead of `id`, you can specify how to normalize just the comments: ```app/serializers/post.js import DS from 'ember-data'; export default DS.RESTSerializer.extend({ normalize(model, hash, prop) { if (prop === 'comments') { hash.id = hash._id; delete hash._id; } return this._super(...arguments); } }); ``` On each call to the `normalize` method, the third parameter (`prop`) is always one of the keys that were in the original payload or in the result of another normalization as `normalizeResponse`. @method normalize @param {DS.Model} modelClass @param {Object} resourceHash @param {String} prop @return {Object} */ normalize(modelClass, resourceHash, prop) { if (this.normalizeHash && this.normalizeHash[prop]) { deprecate('`RESTSerializer.normalizeHash` has been deprecated. Please use `serializer.normalize` to modify the payload of single resources.', false, { id: 'ds.serializer.normalize-hash-deprecated', until: '3.0.0' }); this.normalizeHash[prop](resourceHash); } return this._super(modelClass, resourceHash); }, /** Normalizes an array of resource payloads and returns a JSON-API Document with primary data and, if any, included data as `{ data, included }`. @method _normalizeArray @param {DS.Store} store @param {String} modelName @param {Object} arrayHash @param {String} prop @return {Object} @private */ _normalizeArray(store, modelName, arrayHash, prop) { let documentHash = { data: [], included: [] }; let modelClass = store.modelFor(modelName); let serializer = store.serializerFor(modelName); makeArray(arrayHash).forEach((hash) => { let { data, included } = this._normalizePolymorphicRecord(store, hash, prop, modelClass, serializer); documentHash.data.push(data); if (included) { documentHash.included.push(...included); } }); return documentHash; }, _normalizePolymorphicRecord(store, hash, prop, primaryModelClass, primarySerializer) { let serializer = primarySerializer; let modelClass = primaryModelClass; let primaryHasTypeAttribute = modelHasAttributeOrRelationshipNamedType(primaryModelClass); if (!primaryHasTypeAttribute && hash.type) { // Support polymorphic records in async relationships let modelName; if (isEnabled("ds-payload-type-hooks")) { modelName = this.modelNameFromPayloadType(hash.type); let deprecatedModelNameLookup = this.modelNameFromPayloadKey(hash.type); if (modelName !== deprecatedModelNameLookup && !this._hasCustomModelNameFromPayloadType() && this._hasCustomModelNameFromPayloadKey()) { deprecate("You are using modelNameFromPayloadKey to normalize the type for a polymorphic relationship. This is has been deprecated in favor of modelNameFromPayloadType", false, { id: 'ds.rest-serializer.deprecated-model-name-for-polymorphic-type', until: '3.0.0' }); modelName = deprecatedModelNameLookup; } } else { modelName = this.modelNameFromPayloadKey(hash.type); } if (store._hasModelFor(modelName)) { serializer = store.serializerFor(modelName); modelClass = store.modelFor(modelName); } } return serializer.normalize(modelClass, hash, prop); }, /* @method _normalizeResponse @param {DS.Store} store @param {DS.Model} primaryModelClass @param {Object} payload @param {String|Number} id @param {String} requestType @param {Boolean} isSingle @return {Object} JSON-API Document @private */ _normalizeResponse(store, primaryModelClass, payload, id, requestType, isSingle) { let documentHash = { data: null, included: [] }; let meta = this.extractMeta(store, primaryModelClass, payload); if (meta) { assert('The `meta` returned from `extractMeta` has to be an object, not "' + typeOf(meta) + '".', typeOf(meta) === 'object'); documentHash.meta = meta; } let keys = Object.keys(payload); for (var i = 0, length = keys.length; i < length; i++) { var prop = keys[i]; var modelName = prop; var forcedSecondary = false; /* If you want to provide sideloaded records of the same type that the primary data you can do that by prefixing the key with `_`. Example ``` { users: [ { id: 1, title: 'Tom', manager: 3 }, { id: 2, title: 'Yehuda', manager: 3 } ], _users: [ { id: 3, title: 'Tomster' } ] } ``` This forces `_users` to be added to `included` instead of `data`. */ if (prop.charAt(0) === '_') { forcedSecondary = true; modelName = prop.substr(1); } var typeName = this.modelNameFromPayloadKey(modelName); if (!store.modelFactoryFor(typeName)) { warn(this.warnMessageNoModelForKey(modelName, typeName), false, { id: 'ds.serializer.model-for-key-missing' }); continue; } var isPrimary = (!forcedSecondary && this.isPrimaryType(store, typeName, primaryModelClass)); var value = payload[prop]; if (value === null) { continue; } if (DEBUG) { let isQueryRecordAnArray = requestType === 'queryRecord' && isPrimary && Array.isArray(value); let message = "The adapter returned an array for the primary data of a `queryRecord` response. This is deprecated as `queryRecord` should return a single record."; deprecate(message, !isQueryRecordAnArray, { id: 'ds.serializer.rest.queryRecord-array-response', until: '3.0' }); } /* Support primary data as an object instead of an array. Example ``` { user: { id: 1, title: 'Tom', manager: 3 } } ``` */ if (isPrimary && !Array.isArray(value)) { let { data, included } = this._normalizePolymorphicRecord(store, value, prop, primaryModelClass, this); documentHash.data = data; if (included) { documentHash.included.push(...included); } continue; } let { data, included } = this._normalizeArray(store, typeName, value, prop); if (included) { documentHash.included.push(...included); } if (isSingle) { data.forEach(resource => { /* Figures out if this is the primary record or not. It's either: 1. The record with the same ID as the original request 2. If it's a newly created record without an ID, the first record in the array */ let isUpdatedRecord = isPrimary && coerceId(resource.id) === id; let isFirstCreatedRecord = isPrimary && !id && !documentHash.data; if (isFirstCreatedRecord || isUpdatedRecord) { documentHash.data = resource; } else { documentHash.included.push(resource); } }); } else { if (isPrimary) { documentHash.data = data; } else { if (data) { documentHash.included.push(...data); } } } } return documentHash; }, isPrimaryType(store, typeName, primaryTypeClass) { return store.modelFor(typeName) === primaryTypeClass; }, /** This method allows you to push a payload containing top-level collections of records organized per type. ```js { "posts": [{ "id": "1", "title": "Rails is omakase", "author", "1", "comments": [ "1" ] }], "comments": [{ "id": "1", "body": "FIRST" }], "users": [{ "id": "1", "name": "@d2h" }] } ``` It will first normalize the payload, so you can use this to push in data streaming in from your server structured the same way that fetches and saves are structured. @method pushPayload @param {DS.Store} store @param {Object} payload */ pushPayload(store, payload) { let documentHash = { data: [], included: [] }; for (var prop in payload) { var modelName = this.modelNameFromPayloadKey(prop); if (!store.modelFactoryFor(modelName)) { warn(this.warnMessageNoModelForKey(prop, modelName), false, { id: 'ds.serializer.model-for-key-missing' }); continue; } var type = store.modelFor(modelName); var typeSerializer = store.serializerFor(type.modelName); makeArray(payload[prop]).forEach(hash => { let { data, included } = typeSerializer.normalize(type, hash, prop); documentHash.data.push(data); if (included) { documentHash.included.push(...included); } }); } if (isEnabled('ds-pushpayload-return')) { return store.push(documentHash); } else { store.push(documentHash); } }, /** This method is used to convert each JSON root key in the payload into a modelName that it can use to look up the appropriate model for that part of the payload. For example, your server may send a model name that does not correspond with the name of the model in your app. Let's take a look at an example model, and an example payload: ```app/models/post.js import DS from 'ember-data'; export default DS.Model.extend({ }); ``` ```javascript { "blog/post": { "id": "1 } } ``` Ember Data is going to normalize the payload's root key for the modelName. As a result, it will try to look up the "blog/post" model. Since we don't have a model called "blog/post" (or a file called app/models/blog/post.js in ember-cli), Ember Data will throw an error because it cannot find the "blog/post" model. Since we want to remove this namespace, we can define a serializer for the application that will remove "blog/" from the payload key whenver it's encountered by Ember Data: ```app/serializers/application.js import DS from 'ember-data'; export default DS.RESTSerializer.extend({ modelNameFromPayloadKey(payloadKey) { if (payloadKey === 'blog/post') { return this._super(payloadKey.replace('blog/', '')); } else { return this._super(payloadKey); } } }); ``` After refreshing, Ember Data will appropriately look up the "post" model. By default the modelName for a model is its name in dasherized form. This means that a payload key like "blogPost" would be normalized to "blog-post" when Ember Data looks up the model. Usually, Ember Data can use the correct inflection to do this for you. Most of the time, you won't need to override `modelNameFromPayloadKey` for this purpose. @method modelNameFromPayloadKey @param {String} key @return {String} the model's modelName */ modelNameFromPayloadKey(key) { return singularize(normalizeModelName(key)); }, // SERIALIZE /** 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: ```app/models/comment.js 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: ```js { "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. ```app/serializers/post.js import DS from 'ember-data'; export default DS.RESTSerializer.extend({ serialize(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. ```app/serializers/application.js import DS from 'ember-data'; import { pluralize } from 'ember-inflector'; export default DS.RESTSerializer.extend({ serialize(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(singularize(name)) + "_IDS"; } ``` This serializer will generate JSON that looks like this: ```js { "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. ```app/serializers/post.js import DS from 'ember-data'; export default DS.RESTSerializer.extend({ serialize(snapshot, options) { var json = this._super(snapshot, options); json.subject = json.title; delete json.title; return json; } }); ``` @method serialize @param {DS.Snapshot} snapshot @param {Object} options @return {Object} json */ serialize(snapshot, options) { return this._super(...arguments); }, /** You can use this method to customize the root keys serialized into the JSON. The hash property should be modified by reference (possibly using something like _.extend) By default the REST Serializer sends the modelName of a model, which is a camelized version of the name. For example, your server may expect underscored root objects. ```app/serializers/application.js import DS from 'ember-data'; import { decamelize } from '@ember/string'; export default DS.RESTSerializer.extend({ serializeIntoHash(data, type, record, options) { var root = decamelize(type.modelName); data[root] = this.serialize(record, options); } }); ``` @method serializeIntoHash @param {Object} hash @param {DS.Model} typeClass @param {DS.Snapshot} snapshot @param {Object} options */ serializeIntoHash(hash, typeClass, snapshot, options) { let normalizedRootKey = this.payloadKeyFromModelName(typeClass.modelName); hash[normalizedRootKey] = this.serialize(snapshot, options); }, /** You can use `payloadKeyFromModelName` to override the root key for an outgoing request. By default, the RESTSerializer returns a camelized version of the model's name. For a model called TacoParty, its `modelName` would be the string `taco-party`. The RESTSerializer will send it to the server with `tacoParty` as the root key in the JSON payload: ```js { "tacoParty": { "id": "1", "location": "Matthew Beale's House" } } ``` For example, your server may expect dasherized root objects: ```app/serializers/application.js import DS from 'ember-data'; import { dasherize } from '@ember/string'; export default DS.RESTSerializer.extend({ payloadKeyFromModelName(modelName) { return dasherize(modelName); } }); ``` Given a `TacoParty` model, calling `save` on it would produce an outgoing request like: ```js { "taco-party": { "id": "1", "location": "Matthew Beale's House" } } ``` @method payloadKeyFromModelName @param {String} modelName @return {String} */ payloadKeyFromModelName(modelName) { return camelize(modelName); }, /** You can use this method to customize how polymorphic objects are serialized. By default the REST Serializer creates the key by appending `Type` to the attribute and value from the model's camelcased model name. @method serializePolymorphicType @param {DS.Snapshot} snapshot @param {Object} json @param {Object} relationship */ serializePolymorphicType(snapshot, json, relationship) { let key = relationship.key; let typeKey = this.keyForPolymorphicType(key, relationship.type, 'serialize'); let belongsTo = snapshot.belongsTo(key); // old way of getting the key for the polymorphic type key = this.keyForAttribute ? this.keyForAttribute(key, "serialize") : key; key = `${key}Type`; // The old way of serializing the type of a polymorphic record used // `keyForAttribute`, which is not correct. The next code checks if the old // way is used and if it differs from the new way of using // `keyForPolymorphicType`. If this is the case, a deprecation warning is // logged and the old way is restored (so nothing breaks). if (key !== typeKey && this.keyForPolymorphicType === RESTSerializer.prototype.keyForPolymorphicType) { deprecate("The key to serialize the type of a polymorphic record is created via keyForAttribute which has been deprecated. Use the keyForPolymorphicType hook instead.", false, { id: 'ds.rest-serializer.deprecated-key-for-polymorphic-type', until: '3.0.0' }); typeKey = key; } if (isNone(belongsTo)) { json[typeKey] = null; } else { if (isEnabled("ds-payload-type-hooks")) { json[typeKey] = this.payloadTypeFromModelName(belongsTo.modelName); } else { json[typeKey] = camelize(belongsTo.modelName); } } }, /** You can use this method to customize how a polymorphic relationship should be extracted. @method extractPolymorphicRelationship @param {Object} relationshipType @param {Object} relationshipHash @param {Object} relationshipOptions @return {Object} */ extractPolymorphicRelationship(relationshipType, relationshipHash, relationshipOptions) { let { key, resourceHash, relationshipMeta } = relationshipOptions; // A polymorphic belongsTo relationship can be present in the payload // either in the form where the `id` and the `type` are given: // // { // message: { id: 1, type: 'post' } // } // // or by the `id` and a `<relationship>Type` attribute: // // { // message: 1, // messageType: 'post' // } // // The next code checks if the latter case is present and returns the // corresponding JSON-API representation. The former case is handled within // the base class JSONSerializer. let isPolymorphic = relationshipMeta.options.polymorphic; let typeProperty = this.keyForPolymorphicType(key, relationshipType, 'deserialize'); if (isPolymorphic && resourceHash[typeProperty] !== undefined && typeof relationshipHash !== 'object') { if (isEnabled("ds-payload-type-hooks")) { let payloadType = resourceHash[typeProperty]; let type = this.modelNameFromPayloadType(payloadType); let deprecatedTypeLookup = this.modelNameFromPayloadKey(payloadType); if (payloadType !== deprecatedTypeLookup && !this._hasCustomModelNameFromPayloadType() && this._hasCustomModelNameFromPayloadKey()) { deprecate("You are using modelNameFromPayloadKey to normalize the type for a polymorphic relationship. This has been deprecated in favor of modelNameFromPayloadType", false, { id: 'ds.rest-serializer.deprecated-model-name-for-polymorphic-type', until: '3.0.0' }); type = deprecatedTypeLookup; } return { id: relationshipHash, type: type }; } else { let type = this.modelNameFromPayloadKey(resourceHash[typeProperty]); return { id: relationshipHash, type: type }; } } return this._super(...arguments); } }); if (isEnabled("ds-payload-type-hooks")) { RESTSerializer.reopen({ /** `modelNameFromPayloadType` can be used to change the mapping for a DS model name, taken from the value in the payload. Say your API namespaces the type of a model and returns the following payload for the `post` model, which has a polymorphic `user` relationship: ```javascript // GET /api/posts/1 { "post": { "id": 1, "user": 1, "userType: "api::v1::administrator" } } ``` By overwriting `modelNameFromPayloadType` you can specify that the `administrator` model should be used: ```app/serializers/application.js import DS from 'ember-data'; export default DS.RESTSerializer.extend({ modelNameFromPayloadType(payloadType) { return payloadType.replace('api::v1::', ''); } }); ``` By default the modelName for a model is its name in dasherized form. Usually, Ember Data can use the correct inflection to do this for you. Most of the time, you won't need to override `modelNameFromPayloadType` for this purpose. Also take a look at [payloadTypeFromModelName](#method_payloadTypeFromModelName) to customize how the type of a record should be serialized. @method modelNameFromPayloadType @public @param {String} payloadType type from payload @return {String} modelName */ modelNameFromPayloadType(payloadType) { return singularize(normalizeModelName(payloadType)); }, /** `payloadTypeFromModelName` can be used to change the mapping for the type in the payload, taken from the model name. Say your API namespaces the type of a model and expects the following payload when you update the `post` model, which has a polymorphic `user` relationship: ```javascript // POST /api/posts/1 { "post": { "id": 1, "user": 1, "userType": "api::v1::administrator" } } ``` By overwriting `payloadTypeFromModelName` you can specify that the namespaces model name for the `administrator` should be used: ```app/serializers/application.js import DS from 'ember-data'; export default DS.RESTSerializer.extend({ payloadTypeFromModelName(modelName) { return 'api::v1::' + modelName; } }); ``` By default the payload type is the camelized model name. Usually, Ember Data can use the correct inflection to do this for you. Most of the time, you won't need to override `payloadTypeFromModelName` for this purpose. Also take a look at [modelNameFromPayloadType](#method_modelNameFromPayloadType) to customize how the model name from should be mapped from the payload. @method payloadTypeFromModelName @public @param {String} modelName modelName from the record @return {String} payloadType */ payloadTypeFromModelName(modelName) { return camelize(modelName); }, _hasCustomModelNameFromPayloadKey() { return this.modelNameFromPayloadKey !== RESTSerializer.prototype.modelNameFromPayloadKey; }, _hasCustomModelNameFromPayloadType() { return this.modelNameFromPayloadType !== RESTSerializer.prototype.modelNameFromPayloadType; }, _hasCustomPayloadTypeFromModelName() { return this.payloadTypeFromModelName !== RESTSerializer.prototype.payloadTypeFromModelName; }, _hasCustomPayloadKeyFromModelName() { return this.payloadKeyFromModelName !== RESTSerializer.prototype.payloadKeyFromModelName; } }); } if (DEBUG) { RESTSerializer.reopen({ warnMessageNoModelForKey(prop, typeKey) { return 'Encountered "' + prop + '" in payload, but no model was found for model name "' + typeKey + '" (resolved model name using ' + this.constructor.toString() + '.modelNameFromPayloadKey("' + prop + '"))'; } }); } export default RESTSerializer;