simple rest fetch api

api.js

import 'whatwg-fetch'
import store from './store'

function _buildUrl (path, query) {
  let url = path
  if (query !== undefined) {
    let queryArray = []
    for (const key of Object.keys(query)) {
      queryArray = [...queryArray, `${encodeURIComponent(key)}=${encodeURIComponent(query[key])}`]
    }
    const queryString = queryArray.join('&')
    url = `${url}?${queryString}`
  }

  return url
}

function _buildOptions (method, data) {
  if (method === undefined) {
    let error = new Error('method is required')
    throw error
  }
  let options = {
    method: method,
    headers: {
      'Accept': 'application/json'
    }
  }

  const usersState = store.getState().users
  const token = usersState ? usersState.token : undefined
  if (token !== undefined) {
    options.headers['Authorization'] = `Bearer ${token}`
  }

  if (data !== undefined) {
    if (data instanceof FormData) {
      options.body = data
    } else {
      options.headers['Content-Type'] = 'application/json'
      options.body = JSON.stringify(data)
    }
  }

  return options
}

function _parseJson (response) {
  if (response.status === 204) {
    return
  }
  return response.json().then((json) => {
    if (response.status >= 200 && response.status < 300) {
      return json
    } else {
      let error = new Error(response.statusText)
      error.json = json
      throw error
    }
  })
}

function _request (path, query, data, method) {
  const url = _buildUrl(path, query)
  const options = _buildOptions(method, data)

  return fetch(url, options).then(_parseJson)
}

function get (path, query) {
  return _request(path, query, undefined, 'get')
}

function post (path, data, query) {
  return _request(path, query, data, 'post')
}

function put (path, data, query) {
  return _request(path, query, data, 'put')
}

function patch (path, data, query) {
  return _request(path, query, data, 'patch')
}

function del (path, query) {
  return _request(path, query, undefined, 'delete')
}

export default {
  _buildUrl,
  _buildOptions,
  _parseJson,
  get,
  post,
  put,
  patch,
  del
}