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FetchQL

FetchQL is a query client for GraphQL server works on both browser and Node(need fetch support, eg. node-fetch)

New in v3.0.0

New TypeScript declaration file(.tsd). #9

Upgrade to 2.2.0

Now FetchQL distributes an ES module(./lib/fetchql.es.js) by default and you can simply import FetchQL by import fetchql from 'fetchql'.

For details, please refer to PR: Added support for ES modules by default.

Breaking Changes(since v2.0.0)

Source code has been moved into ./src and distributed file goes to ./lib;
Distributed file(./lib/fetchql.js) is unminified now.

Pros:

lightweight
wrap query methods
easily set server-side
get enum types by names (with cache)
built-in interceptors
request state callbacks
written in ES2015 and modules

Usage

FetchQL distributes both ES module and CommonJS module

Import FetchQL:

import FetchQL from 'fetchql'
const FetchQL = require('fetchql')

ES module support is determined by your bundler tool(webpack, rollup, etc.).

Documentation

Class FetchQL

var Query = new FetchQL({ url, interceptors, headers, onStart, onEnd, omitEmptyVariables })

{
  url: '', // GraphQL server address
  interceptors: [],
  headers: {}, // customized headers of all requests,
  onStart: function (requestQueueLength) {}, // callback of a new request queue
  onEnd: function (requestQueueLength) {} // callback of a request queue finished
  omitEmptyVariables: false, // remove null props(null or '') from the variables
}

interceptor

interceptors is an optional parameter of the class. It can be an Array or an Object.

{
  url: '',
  interceptors: [interceptor]
  // or
  // interceptors: interceptor
}

// interceptor
{
  request: function (url, config) {
      // Modify the url or config here
      return [url, config];
  },

  requestError: function (error) {
      // Called when an error occured during another 'request' interceptor call
      return Promise.reject(error);
  },

  response: function (response) {
      // Modify the reponse object
      return response;
  },

  responseError: function (error) {
      // Handle an fetch error
      return Promise.reject(error);
  }
}

FetchQL.addInterceptors(interceptor[]|interceptor) => function

Add more interceptors. Arguments are same with interceptors of class.

It will return a function to remove added interceptors.
FetchQL.clearInterceptors() => void

Remove all interceptors.

FetchQL.query()

Query.query({operationName: '', query: '', variables: {}, opts: {}}) => Promise

Method for query data from the server. operationName must be provided.

query and variables are followed the specification fo GraphQL.

If Data was missing or null, or if all fields of data was null, will reject the promise.
- opts - additional options(will not be passed to server)
  - opts.omitEmptyVariables - similar to omitEmptyVariables global settings, remove null props(null or '') from the variables
FetchQL.getEnumTypes()

Query.getEnumTypes(['array', 'of', 'enum', 'name']) => Promise

Will get enums' information from the server. Then you can get the following Object in the promise:
```
{
  array: {
    name: '',
    kind: '',
    description: '',
    enumValues: {
      name: '',
      description: '',
    }
  },
  of: {...},
  enum: {...},
  name: {...}
}
```
This method currently supports caching. All enum will be cached after first querying.
FetchQL.getUrl()

Return current server address.
FetchQL.setUrl()

Query.setUrl('')

Set a new server address.
callback - onStart(requestQueueLength), onEnd(requestQueueLength)

When FetchQL make a new request, if it belongs to a new queue(means there are no requests before), will call onStart().

By this, you can know that now there are some network requests within FetchQL.

When FetchQL finishes a request and find that there are no requests anymore, will call onEnd().

By this, you can know that all requests within FetchQL have been finished.

These two callbacks are useful when you want to watch the state of FetchQL's network requesting.

For example, you may have an indicator(loading spinner, loading bar) in your web application, with this feature you can easily manage the indicator's state(display or not);
omitEmptyVariables - Boolean(default to false) remove null props(null or '') from the variables in query

Sometimes null or '' could be different meanings in backend logic.

And if you just want the backend to ignore these variables, use this option to remove them.

Notice: Only properties those in an object of 'variables', will be removed.
```
{ willNotRemove: '', obj: { emptyString: '', nullProp: null } } => { willNotRemove: '', obj: {} } // remove them
```
requestOptions - Object change request options of fetch in FetchQL.
```
var ql = new FetchQL(
  {
    requestOptions: {
      credentials: 'include',
    },
  }
);

ql.query(
  {
    requestOptions: {
      credentials: 'same-origin',
    },
  }
);
```
requestOptions in FetchQL's new constructor or query is used to change request options of fetch method in FetchQL.

Set it in the new constructor will change default request options in all query in FetchQL.

Set it in query method will only change request options of the current query.

Tips

FetchQL in angularjs

.js or .mjs

Use index.js in any ES2015 environment.
Use index.mjs for Node (version >= 6.0) without babel, because Node doesn't support ES2015 modules natively.

Develop

npm install

./test/server.js could be used as a development server.

LICENSE

The MIT License (MIT)

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.