Add stateful OAuth flow

package.json

@@ -4,12 +4,13 @@
   "description": "Javascript library to interact with a cozy",
   "main": "src/index.js",
   "scripts": {
-    "build": "NODE_ENV=production webpack",
+    "build": "NODE_ENV=production NODE_TARGET=web webpack",
+    "watch": "NODE_ENV=production NODE_TARGET=web webpack --watch",
     "lint": "standard './src/**/*.js' './test/**/*.js' webpack.config.js",
     "test": "npm run test:unit && npm run test:v2 && npm run test:v3",
-    "test:unit": "NODE_ENV=test mocha-webpack 'test/unit/**.js'",
-    "test:v2": "NODE_ENV=test TARGET=http://localhost:9104 mocha-webpack 'test/integration/**.js'",
-    "test:v3": "NODE_ENV=test TARGET=http://localhost:8080 mocha-webpack 'test/integration/**.js'",
+    "test:unit": "NODE_ENV=test NODE_TARGET=node mocha-webpack 'test/unit/**.js'",
+    "test:v2": "NODE_ENV=test NODE_TARGET=node COZY_STACK_VERSION=2 COZY_STACK_URL=http://localhost:9104 mocha-webpack 'test/integration/**.js'",
+    "test:v3": "NODE_ENV=test NODE_TARGET=node COZY_STACK_VERSION=3 COZY_STACK_URL=http://localhost:8080 mocha-webpack 'test/integration/**.js'",
     "clean": "rm -r dist && rm -r .tmp"
   },
   "repository": {
@@ -48,8 +49,7 @@
     "standard": "8.6.0",
     "standard-loader": "5.0.0",
     "webpack": "1.13.3",
-    "webpack-node-externals": "1.5.4",
-    "whatwg-fetch": "1.0.0"
+    "webpack-node-externals": "1.5.4"
   },
   "/#######################################################": "",
   "# this repo works as a cozy v2 client-side application #": "",

src/auth_storage.js

@@ -0,0 +1,98 @@
+export class LocalStorage {
+  constructor (prefix = 'cozy:oauth:', getLocalStorage = () => window.localStorage) {
+    // We try to deref the localstorage, and if it fails (because the user has
+    // deactivated its localstorage for instance) we fallback on a memory
+    // storage.
+    let storage
+    try {
+      storage = getLocalStorage()
+    } catch (e) {
+      storage = memStorage
+    }
+    this.storage = storage
+    this.prefix = prefix
+  }
+
+  save (key, value) {
+    return new Promise(resolve => resolve(
+      this.storage.setItem(this.prefix + key, JSON.stringify(value))))
+  }
+
+  load (key) {
+    return new Promise(resolve => {
+      const item = this.storage.getItem(this.prefix + key)
+      if (!item) {
+        resolve()
+      } else {
+        resolve(JSON.parse(item))
+      }
+    })
+  }
+
+  delete (key) {
+    return new Promise(resolve => resolve(
+      this.storage.removeItem(this.prefix + key)))
+  }
+
+  clear () {
+    return new Promise(resolve => {
+      const storage = this.storage
+      for (let i = 0; i < storage.length; i++) {
+        const key = storage.key(i)
+        if (key.indexOf(this.prefix) === 0) {
+          storage.removeItem(key)
+        }
+      }
+      resolve()
+    })
+  }
+}
+
+export class MemoryStorage {
+  constructor () {
+    this.hash = {}
+  }
+
+  save (key, value) {
+    return Promise.resolve(this.hash[key] = value)
+  }
+
+  load (key) {
+    return Promise.resolve(this.hash[key])
+  }
+
+  delete (key) {
+    return Promise.resolve(delete this.hash[key])
+  }
+
+  clear () {
+    return Promise.resolve(this.hash = {})
+  }
+}
+
+const memStorage = {
+  _h: {},
+  _k: [],
+  length: 0,
+  setItem (key, value) {
+    if (!this._h.hasOwnProperty(key)) {
+      this._k.push(key)
+      this.length++
+    }
+    this._h[key] = value
+  },
+  getItem (key) {
+    return this._h[key]
+  },
+  removeItem (key) {
+    if (delete this._h[key]) {
+      this._k.splice(this._k.indexOf(key), 1)
+      this.length--
+      return true
+    }
+    return false
+  },
+  key (index) {
+    return this._k[index]
+  }
+}

src/auth_v2.js

@@ -0,0 +1,54 @@
+/* global btoa */
+const V2TOKEN_ABORT_TIMEOUT = 3000
+
+export function getAccessToken () {
+  return new Promise(function (resolve, reject) {
+    if (typeof window === 'undefined') {
+      return reject(new Error('getV2Token should be used in browser'))
+    } else if (!window.parent) {
+      return reject(new Error('getV2Token should be used in iframe'))
+    } else if (!window.parent.postMessage) {
+      return reject(new Error('getV2Token should be used in modern browser'))
+    }
+    const origin = window.location.origin
+    const intent = {action: 'getToken'}
+    let timeout = null
+    const receiver = function (event) {
+      let token
+      try {
+        token = new AccessToken({
+          appName: event.data.appName,
+          token: event.data.token
+        })
+      } catch (e) {
+        reject(e)
+        return
+      }
+      window.removeEventListener('message', receiver)
+      clearTimeout(timeout)
+      resolve({ client: null, token })
+    }
+    window.addEventListener('message', receiver, false)
+    window.parent.postMessage(intent, origin)
+    timeout = setTimeout(() => {
+      reject(new Error('No response from parent iframe after 3s'))
+    }, V2TOKEN_ABORT_TIMEOUT)
+  })
+}
+
+export class AccessToken {
+  constructor (opts) {
+    this.appName = opts.appName || ''
+    this.token = opts.token || ''
+    if (this.appName === '') {
+      throw new Error('Missing appName parameter')
+    }
+    if (this.token === '') {
+      throw new Error('Missing token parameter')
+    }
+  }
+
+  toAuthHeader () {
+    return 'Basic ' + btoa(`${this.appName}:${this.token}`)
+  }
+}