KTH API Call for Node

Node module used to make JSON calls against APIs. (Previously published as kth-node-api-call, now @kth/api-call.)

To use in your node project, run:

npm i @kth/api-call

Setup

In your init callback to the Express web server, this should happen:

const connections = require('@kth/api-call').Connections

const nodeApi = {
  namedApi: {
    host: 'localhost', // api hostname
    https: false, // use ssl?
    port: 3001, // api port
    proxyBasePath: '/api/applicationName', // api base path
    required: true, // is the api required? Optional, defaults to false
    defaultTimeout: 2000, // milliseconds. Optional, defaults to 2000
  },
}

const cacheConfig = {
  namedApi: {
    redis: {
      host: 'localhost',
      port: 6379,
    },
  },
}

const apiKey = {
  namedApi: '1234',
}

const options = {
  timeout: 5000, // milliseconds, retry interval if getting API-paths fails
  log: myLogger, // your logger instance
  redis: myRedis, // optional kth-node-redis instance
  cache: cacheConfig, // your api cache options
  checkAPIs: true,
}
// either
module.exports = connections.setup(nodeApi, apiKey, options)
// or
const api = connections.setup(nodeApi, apiKey, options)

Note

The checkAPIs option requires that the API implements a checkAPIkey route, see node-api The endpoint can be overridden by setting the statusCheckPath property on the api config object

Usage

Wherever you need to call your api, use something on the form of:

const paths = api.namedApi.paths
const client = api.namedApi.client

// user is a uri parameter
client.getAsync(client.resolve(paths.[YOUR_ENDPOINT], {user: username, etc...}))
.then(response => {
  // do something with result
})

if you want to use a cached api, add the option {useCache: true} to the getAsync call like this:

client.getAsync([FULL_PATH], { useCache: true }).then(response => {
  // etc.
})

BasicAPI

This used to be a straightforward wrapper around request. Since version 4, request is replaced by node-fetch, with efforts made to keep the same methods.

BasicAPI will allow more control but also encourage more code re-use. It allows the use of Promises and caching (via redis) of successful responses (status >= 200 and status < 400).

For more details see the examples below and the source code.

// configure this and re-use throughout your app

const api = new BasicAPI({
  hostname: 'localhost',
  port: 3001,
  json: true,
  https: false,
  headers: {
    api_key: 'abcd',
  },
  // optionally enable redis for response caching
  // redis: {
  //   client: redisClient,
  //   prefix: 'node-api',
  //   expire: 120
  // }
})

// usage example:

const params = { id: 123 }
const uri = api.resolve('/value/:id', params)

// promise
api
  .getAsync(uri)
  .then(response => {
    if (response.statusCode >= 200 && response.statusCode < 400) {
      // do something with response.body
    } else {
      // bad/unexpected status code, delegate error
    }
  })
  .catch(err => {
    // handle/delegate err
  })

// or callback
api.get(uri, (err, response, body) => {
  if (err) {
    // handle/delegate err
    return
  }

  if (response.statusCode >= 200 && response.statusCode < 400) {
    // do something with response.body
  } else {
    // bad/unexpected status code, delegate error
  }
})

HTTP Request Methods

Each of the following sends a corresponding HTTP request. Append Async (e.g. getAsync) to use Promise instead of callback. The first parameter should be either a uri (as a string) or an options object which is passed to node-fetch. For non-async methods the second parameter should be a function with the following signature: function (error, response, body) { ... }. The callback parameters are the same as for the request library.

Note that if you use Redis and/or the async methods you might lose some functionality. For details about this, read the source code!

• get/getAsync
• post/postAsync
• put/putAsync
• del/delAsync
• head/headAsync
• patch/patchAsync

Utility Methods

• resolve takes two parameters. The first is a uri template, e.g. /value/:name, and the second is a plain object, e.g. { name: 'foo' }. It will then replace :name with the matching values in the object, resolving the uri /value/foo.
• defaults re-uses the same config and applies another configuration set on top. Basically it does the same as request.defaults() but returns a valid BasicAPI instance.

Migration from version 3 to 4

• jar and cookie were basic wrappers to the corresponding request methods. They were removed in version 4.
• defaults was deprecated in version 4. Use new BasicAPI(options) instead.