Koa-api-combo NPM

koa-api-combo

proxy multiple http or https requests, and response the result array by combine all the result.

Usage

const Combo = require('koa-api-combo');

// GET /combo?urls=encodeURIComponent('/x,/xx?xxx,/xxx')&...
app.use(Combo('/combo', { apiHost: 'a.com' });
// equals to
// GET /x?...
// GET /xx?xxx&...
// GET /xxx?...

// GET /combo?urls=encodeURIComponent('/x,/xx?xxx,/xxx')&...
// GET /combo/ignore?urls=encodeURIComponent('/x,/xx?xxx,/xxx')&...
// the request result data will be set to null if the request is error
// and the result should be like [null] [null, {"a":1}] ...
app.use(Combo.withIgnoreError('/combo', { apiHost: 'a.com' }));

Install

npm install koa-api-combo --save

Middleware

`Combo(path, comboConfig, apiRequestConfig)`

@param {string} path is the route string. And should be exactly equal to ctx.path
@param {Object} apiRequestConfig the same as ApiRequest
@param {Object} comboConfig
@param {boolean} comboConfig.supportIgnoreError will use null instead the response data if request url error,

  and need request by append `/ignore` to the `path` parameter if set to true

@param {Function} comboConfig.isValidUrl for filter possible illegal url if needed, and response 400 with parameters error

`ApiRequest(config)`

@param {string} config.apiHost
@param {number} config.port
@param {string} config.protocol=http the protocol that request api server
@param {number} config.dnsCacheTime=10 the time for dns cache, default 10 seconds, do not use dns cache if set 0
@param {number} config.timeout=7 timeout for each api request, default 7 seconds
@param {boolean} config.compress=false whether accept encoding from api server, and only gzip and deflate support.
@param {string} config.headers='Cookie,User-Agent,Referrer' the header you want to send to api server

Query

The key of query is urls.

The value is the url array separate from ,, and should encode it by use encodeURIComponent.

Each url can have ? and &, and will append with the querystring from ctx.querystring except urls.

So this means parameters are shared by each url if you set other parameter but urls to current request.

Some Example:

GET /combo?urls=/a,/b&p=1 # urls=encodeURIComponent('/a,/b')
// equivalent to
// /a?p=1 and /b?p=1

GET /combo?h=2&urls=/a?c=1,/b?p=1&p=1 # urls=encodeURIComponent('/a?c=1,/b?p=1')
// equivalent to
// /a?c=1&h=2&p=1 and /b?p=1&h=2&p=1

Note::: it just append to the url for the same query! And query from url is first.