--- outline: deep --- # REST Client The following chapter describes the use of - [@feathersjs/rest-client](#feathersjsrest-client) as a client side Feathers HTTP API integration - [Direct connection](#http-api) with any other HTTP client ## rest-client [![npm version](https://img.shields.io/npm/v/@feathersjs/client.svg?style=flat-square)](https://www.npmjs.com/package/@feathersjs/rest-client) [![Changelog](https://img.shields.io/badge/changelog-.md-blue.svg?style=flat-square)](https://github.com/feathersjs/feathers/blob/dove/packages/rest-client/CHANGELOG.md) ``` npm install @feathersjs/rest-client --save ``` `@feathersjs/rest-client` allows to connect to a service exposed through a REST HTTP transport (e.g. with [Koa](../koa.md#rest) or [Express](../express.md#rest)) using [fetch](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API), [Superagent](http://visionmedia.github.io/superagent/) or [Axios](https://github.com/mzabriskie/axios).
For directly using a Feathers REST API (via HTTP) without using Feathers on the client see the [HTTP API](#http-api) section.
REST client services do emit `created`, `updated`, `patched` and `removed` events but only _locally for their own instance_. Real-time events from other clients can only be received by using a real-time transport ([Socket.io](./socketio.md)).
A client application can only use a single transport (e.g. either REST or Socket.io). Using two transports in the same client application is normally not necessary.
### rest([baseUrl]) REST client services can be initialized by loading `@feathersjs/rest-client` and initializing a client object with a base URL.
In the browser, the base URL is relative from where services are registered. That means that a service at `http://api.feathersjs.com/api/v1/messages` with a base URL of `http://api.feathersjs.com` would be available as `app.service('api/v1/messages')`. With a base URL of `http://api.feathersjs.com/api/v1` it would be `app.service('messages')`.
``` javascript const feathers = require('@feathersjs/feathers'); const rest = require('@feathersjs/rest-client'); const app = feathers(); // Connect to the same as the browser URL (only in the browser) const restClient = rest(); // Connect to a different URL const restClient = rest('http://feathers-api.com') // Configure an AJAX library (see below) with that client app.configure(restClient.fetch(window.fetch.bind(window))); // Connect to the `http://feathers-api.com/messages` service const messages = app.service('messages'); ``` ``` html ``` > **ProTip:** When `window.fetch` (or just `fetch` which is normally equal to `window.fetch`) is passed to the FeathersJS REST client, its context (`this`) has to be bound to `window` (using `bind(window)` on it). Otherwise `window.fetch` would be called by the FeathersJS REST client with incorrect context, causing a JavaScript error: `Failed to execute 'fetch' on 'Window': Illegal invocation`. > **ProTip:** ### params.headers Request specific headers can be through `params.headers` in a service call: ```js app.service('messages').create({ text: 'A message from a REST client' }, { headers: { 'X-Requested-With': 'FeathersJS' } }); ``` ### params.connection Allows to pass additional options specific to the AJAX library. `params.connection.headers` will be merged with `params.headers`: ```js app.configure(restClient.axios(axios)); app.service('messages').get(1, { connection: { // Axios specific options here } }); ``` With the `fetch` fork [yetch](https://github.com/Netflix/yetch) it can also be used to abort requests: ```js const yetch = require('yetch'); const controller = new AbortController(); app.configure(restClient.fetch(yetch)); const promise = app.service('messages').get(1, { connection: { signal: controller.signal } }); promise.abort(); ``` ### app.rest `app.rest` contains a reference to the `connection` object passed to `rest().(connection)`. ### Request libraries The Feathers REST client can be used with several HTTP request libraries. #### Fetch Fetch uses a default configuration: ```js // In Node const fetch = require('node-fetch'); app.configure(restClient.fetch(fetch)); // In modern browsers app.configure(restClient.fetch(window.fetch)); ``` #### Superagent [Superagent](http://visionmedia.github.io/superagent/) currently works with a default configuration: ```js const superagent = require('superagent'); app.configure(restClient.superagent(superagent)); ``` #### Axios [Axios](http://github.com/mzabriskie/axios) currently works with a default configuration: ```js const axios = require('axios'); app.configure(restClient.axios(axios)); ``` To use default values for all requests, `axios.create` with [the axios configuration](https://axios-http.com/docs/req_config) can be used: ```js const axios = require('axios'); app.configure(restClient.axios(axios.create({ headers: {'X-Requested-With': 'My-Feathers-Frontend'} }))); ``` ### Custom Methods On the client, [custom service methods](../services.md#custom-methods) are also registered using the `methods` option when registering the service via `restClient.service()`: ```typescript import { feathers, CustomMethod } from '@feathersjs/feathers'; import rest, { RestService } from '@feathersjs/rest-client'; // `data` and return type of custom method type CustomMethodData = { name: string } type CustomMethodResponse = { acknowledged: boolean } type ServiceTypes = { // The type is a RestService extended with custom methods myservice: RestService & { myCustomMethods: CustomMethod } } const client = feathers(); // Connect to the same as the browser URL (only in the browser) const restClient = rest().fetch(window.fetch); // Connect to a different URL const restClient = rest('http://feathers-api.com').fetch(window.fetch); // Configure an AJAX library (see below) with that client client.configure(restClient); // Register a REST client service with all methods listed client.use('myservice', restClient.service('myservice'), { methods: ['find', 'get', 'create', 'update', 'patch', 'remove', 'myCustomMethod'] }); // Then it can be used like other service methods client.service('myservice').myCustomMethod(data, params); ``` ```js const feathers = require('@feathersjs/feathers'); const rest = require('@feathersjs/rest-client'); const client = feathers(); // Connect to the same as the browser URL (only in the browser) const restClient = rest(); // Connect to a different URL const restClient = rest('http://feathers-api.com').fetch(window.fetch.bind(window)) // Configure an AJAX library (see below) with that client client.configure(restClient); // Register a REST client service with all methods listed client.use('myservice', restClient.service('myservice'), { methods: ['find', 'get', 'create', 'update', 'patch', 'remove', 'myCustomMethod'] }); // Then it can be used like other service methods client.service('myservice').myCustomMethod(data, params); ``` > __Note:__ Just like on the server *all* methods you want to use have to be listed in the `methods` option. ### Connecting to multiple servers It is possible to instantiate and use individual services pointing to different servers by calling `rest('server').().service(name)`: ```js const feathers = require('@feathersjs/feathers'); const rest = require('@feathersjs/rest-client'); const app = feathers(); const client1 = rest('http://feathers-api.com').fetch(window.fetch.bind(window)); const client2 = rest('http://other-feathers-api.com').fetch(window.fetch.bind(window)); // With additional options to e.g. set authentication information const client2 = rest('http://other-feathers-api.com').fetch(window.fetch.bind(window),{ headers: { Authorization: 'Bearer ' } }); // Configuring this will initialize default services for http://feathers-api.com app.configure(client1); // Connect to the `http://feathers-api.com/messages` service const messages = app.service('messages'); // Register /users service that points to http://other-feathers-api.com/users app.use('/users', client2.service('users')); const users = app.service('users'); ``` > __Note:__ If the authentication information is different, it needs to be set as an option as shown above or via `params.headers` when making the request. ### Extending rest clients This can be useful if you wish to override how the query is transformed before it is sent to the API. ```js // In Node const fetch = require('node-fetch'); const { FetchClient } = require('@feathersjs/rest-client'); const qs = require('qs'); class CustomFetch extends FetchClient { getQuery (query) { if (Object.keys(query).length !== 0) { const queryString = qs.stringify(query, { strictNullHandling: true }); return `?${queryString}`; } return ''; } } app.configure(restClient.fetch(fetch, CustomFetch)); ``` ## HTTP API You can communicate with a Feathers REST API using any other HTTP REST client. The following section describes what HTTP method, body and query parameters belong to which service method call. All query parameters in a URL will be set as `params.query` on the server. Other service parameters can be set through [hooks](../hooks.md) and [Express middleware](../express.md). URL query parameter values will always be strings. Conversion (e.g. the string `'true'` to boolean `true`) can be done in a hook as well. The body type for `POST`, `PUT` and `PATCH` requests is determined by the Express [body-parser](http://expressjs.com/en/4x/api.html#express.json) middleware which has to be registered *before* any service. You should also make sure you are setting your `Accept` header to `application/json`. Here is the mapping of service methods to REST API calls: | Service method | HTTP method | Path | |-----------------|-------------|-------------| | .find() | GET | /messages | | .get() | GET | /messages/1 | | .create() | POST | /messages | | .update() | PUT | /messages/1 | | .patch() | PATCH | /messages/1 | | .remove() | DELETE | /messages/1 | ### Authentication Authenticating HTTP (REST) requests is a two step process. First you have to obtain a JWT from the [authentication service](../authentication/service.md) by POSTing the strategy you want to use: ```json // POST /authentication the Content-Type header set to application/json { "strategy": "local", "email": "your email", "password": "your password" } ``` Here is what that looks like with curl: ```bash curl -H "Content-Type: application/json" -X POST -d '{"strategy":"local","email":"your email","password":"your password"}' http://localhost:3030/authentication ``` Then to authenticate subsequent requests, add the returned `accessToken` to the `Authorization` header as `Bearer `: ```bash curl -H "Content-Type: application/json" -H "Authorization: Bearer " http://localhost:3030/messages ``` For more information see the [authentication API documentation](../). ### find Retrieves a list of all matching resources from the service ``` GET /messages?status=read&user=10 ``` Will call `messages.find({ query: { status: 'read', user: '10' } })` on the server. If you want to use any of the built-in find operands ($le, $lt, $ne, $eq, $in, etc.) the general format is as follows: ``` GET /messages?field[$operand]=value&field[$operand]=value2 ``` For example, to find the records where field _status_ is not equal to **active** you could do ``` GET /messages?status[$ne]=active ``` The find API allows the use of $limit, $skip, $sort, and $select in the query. These special parameters can be passed directly inside the query object: ``` // Find all messages that are read, limit to 10, only include text field. {"read":"1", "$limit":10, "$select": ["name"] } } // JSON GET /messages?read=1&$limit=10&$select[]=text // HTTP ``` More information about the possible parameters for official database adapters can be found [in the database querying section](../databases/querying.md). ### get Retrieve a single resource from the service. ``` GET /messages/1 ``` Will call `messages.get(1, {})` on the server. ``` GET /messages/1?fetch=all ``` Will call `messages.get(1, { query: { fetch: 'all' } })` on the server. ### create Create a new resource with `data` which may also be an array. ``` POST /messages { "text": "I really have to iron" } ``` Will call `messages.create({ "text": "I really have to iron" }, {})` on the server. ``` POST /messages [ { "text": "I really have to iron" }, { "text": "Do laundry" } ] ``` > **Note:** With a [database adapters](../databases/adapters.md) the [`multi` option](../databases/common.md) has to be set explicitly to support creating multiple entries. ### update Completely replace a single or multiple resources. ``` PUT /messages/2 { "text": "I really have to do laundry" } ``` Will call `messages.update(2, { "text": "I really have to do laundry" }, {})` on the server. When no `id` is given by sending the request directly to the endpoint something like: ``` PUT /messages?complete=false { "complete": true } ``` Will call `messages.update(null, { "complete": true }, { query: { complete: 'false' } })` on the server. > **ProTip:** `update` is normally expected to replace an entire resource which is why the database adapters only support `patch` for multiple records. ### patch Merge the existing data of a single or multiple resources with the new `data`. ``` PATCH /messages/2 { "read": true } ``` Will call `messages.patch(2, { "read": true }, {})` on the server. When no `id` is given by sending the request directly to the endpoint something like: ``` PATCH /messages?complete=false { "complete": true } ``` Will call `messages.patch(null, { complete: true }, { query: { complete: 'false' } })` on the server to change the status for all read messages. > **Note:** With a [database adapters](../databases/adapters.md) the [`multi` option](../databases/common.md) has to be set to support patching multiple entries. This is supported out of the box by the Feathers [database adapters](../databases/adapters.md) ### remove Remove a single or multiple resources: ``` DELETE /messages/2?cascade=true ``` Will call `messages.remove(2, { query: { cascade: 'true' } })`. When no `id` is given by sending the request directly to the endpoint something like: ``` DELETE /messages?read=true ``` Will call `messages.remove(null, { query: { read: 'true' } })` to delete all read messages. > **Note:** With a [database adapters](../databases/adapters.md) the [`multi` option](../databases/common.md) has to be set to support patching multiple entries. ### Custom methods [Custom service methods](../services.md#custom-methods) can be called directly via HTTP by sending a POST request and setting the `X-Service-Method` header to the method you want to call: ``` POST /messages X-Service-Method: myCustomMethod { "message": "Hello world" } ``` Via CURL: ```bash curl -H "Content-Type: application/json" -H "X-Service-Method: myCustomMethod" -X POST -d '{"message": "Hello world"}' http://localhost:3030/myservice ```