/*global Web3*/
cleanContextForImports ( )
require ( 'web3/dist/web3.min.js' )
const log = require ( 'loglevel' )
const LocalMessageDuplexStream = require ( 'post-message-stream' )
const setupDappAutoReload = require ( './lib/auto-reload.js' )
const MetamaskInpageProvider = require ( 'metamask-inpage-provider' )
let isEnabled = false
let warned = false
let providerHandle
let isApprovedHandle
let isUnlockedHandle
restoreContextAfterImports ( )
log . setDefaultLevel ( process . env . METAMASK _DEBUG ? 'debug' : 'warn' )
console . warn ( 'ATTENTION: In an effort to improve user privacy, MetaMask ' +
'stopped exposing user accounts to dapps if "privacy mode" is enabled on ' +
'November 2nd, 2018. Dapps should now call provider.enable() in order to view and use ' +
'accounts. Please see https://bit.ly/2QQHXvF for complete information and up-to-date ' +
'example code.' )
//
// setup plugin communication
//
// setup background connection
var metamaskStream = new LocalMessageDuplexStream ( {
name : 'inpage' ,
target : 'contentscript' ,
} )
// compose the inpage provider
var inpageProvider = new MetamaskInpageProvider ( metamaskStream )
// set a high max listener count to avoid unnecesary warnings
inpageProvider . setMaxListeners ( 100 )
// set up a listener for when MetaMask is locked
window . addEventListener ( 'metamasksetlocked' , ( ) => {
isEnabled = false
} )
// augment the provider with its enable method
inpageProvider . enable = function ( ) {
return new Promise ( ( resolve , reject ) => {
window . removeEventListener ( 'ethereumprovider' , providerHandle )
providerHandle = ( { detail } ) => {
if ( typeof detail . error !== 'undefined' ) {
reject ( detail . error )
} else {
// wait for the publicConfig store to populate with an account
const publicConfig = new Promise ( ( resolve ) => {
const { selectedAddress } = inpageProvider . publicConfigStore . getState ( )
inpageProvider . _metamask . isUnlocked ( ) . then ( unlocked => {
if ( ! unlocked || selectedAddress ) {
resolve ( )
} else {
inpageProvider . publicConfigStore . on ( 'update' , ( { selectedAddress } ) => {
selectedAddress && resolve ( )
} )
}
} )
} )
// wait for the background to update with an accoount
const ethAccounts = new Promise ( ( resolveAccounts , rejectAccounts ) => {
inpageProvider . sendAsync ( { method : 'eth_accounts' , params : [ ] } , ( error , response ) => {
if ( error ) {
rejectAccounts ( error )
} else {
resolveAccounts ( response . result )
}
} )
} )
Promise . all ( [ ethAccounts , publicConfig ] )
. then ( ( [ selectedAddress ] ) => {
isEnabled = true
resolve ( selectedAddress )
} )
. catch ( reject )
}
}
window . addEventListener ( 'ethereumprovider' , providerHandle )
window . postMessage ( { type : 'ETHEREUM_ENABLE_PROVIDER' } , '*' )
} )
}
// add metamask-specific convenience methods
inpageProvider . _metamask = new Proxy ( {
/ * *
* Determines if this domain is currently enabled
*
* @ returns { boolean } - true if this domain is currently enabled
* /
isEnabled : function ( ) {
return isEnabled
} ,
/ * *
* Determines if this domain has been previously approved
*
* @ returns { Promise < boolean > } - Promise resolving to true if this domain has been previously approved
* /
isApproved : function ( ) {
return new Promise ( ( resolve , reject ) => {
window . removeEventListener ( 'ethereumisapproved' , isApprovedHandle )
isApprovedHandle = ( { detail } ) => {
if ( typeof detail . error !== 'undefined' ) {
reject ( detail . error )
} else {
if ( detail . caching ) {
resolve ( ! ! detail . isApproved )
} else {
resolve ( isEnabled )
}
}
}
window . addEventListener ( 'ethereumisapproved' , isApprovedHandle )
window . postMessage ( { type : 'ETHEREUM_IS_APPROVED' } , '*' )
} )
} ,
/ * *
* Determines if MetaMask is unlocked by the user
*
* @ returns { Promise < boolean > } - Promise resolving to true if MetaMask is currently unlocked
* /
isUnlocked : function ( ) {
return new Promise ( ( resolve , reject ) => {
window . removeEventListener ( 'metamaskisunlocked' , isUnlockedHandle )
isUnlockedHandle = ( { detail } ) => {
if ( typeof detail . error !== 'undefined' ) {
reject ( detail . error )
} else {
resolve ( ! ! detail . isUnlocked )
}
}
window . addEventListener ( 'metamaskisunlocked' , isUnlockedHandle )
window . postMessage ( { type : 'METAMASK_IS_UNLOCKED' } , '*' )
} )
} ,
} , {
get : function ( obj , prop ) {
! warned && console . warn ( 'Heads up! ethereum._metamask exposes methods that have ' +
'not been standardized yet. This means that these methods may not be implemented ' +
'in other dapp browsers and may be removed from MetaMask in the future.' )
warned = true
return obj [ prop ]
} ,
} )
// Work around for web3@1.0 deleting the bound `sendAsync` but not the unbound
// `sendAsync` method on the prototype, causing `this` reference issues with drizzle
const proxiedInpageProvider = new Proxy ( inpageProvider , {
// straight up lie that we deleted the property so that it doesnt
// throw an error in strict mode
deleteProperty : ( ) => true ,
} )
window . ethereum = proxiedInpageProvider
//
// setup web3
//
if ( typeof window . web3 !== 'undefined' ) {
throw new Error ( ` MetaMask detected another web3.
MetaMask will not work reliably with another web3 extension .
This usually happens if you have two MetaMasks installed ,
or MetaMask and another web3 extension . Please remove one
and try again . ` )
}
var web3 = new Web3 ( proxiedInpageProvider )
web3 . setProvider = function ( ) {
log . debug ( 'MetaMask - overrode web3.setProvider' )
}
log . debug ( 'MetaMask - injected web3' )
setupDappAutoReload ( web3 , inpageProvider . publicConfigStore )
// export global web3, with usage-detection and deprecation warning
/ * T O D O : U n c o m m e n t t h i s a r e a o n c e a u t o - r e l o a d . j s h a s b e e n d e p r e c a t e d :
let hasBeenWarned = false
global . web3 = new Proxy ( web3 , {
get : ( _web3 , key ) => {
// show warning once on web3 access
if ( ! hasBeenWarned && key !== 'currentProvider' ) {
console . warn ( 'MetaMask: web3 will be deprecated in the near future in favor of the ethereumProvider \nhttps://github.com/MetaMask/faq/blob/master/detecting_metamask.md#web3-deprecation' )
hasBeenWarned = true
}
// return value normally
return _web3 [ key ]
} ,
set : ( _web3 , key , value ) => {
// set value normally
_web3 [ key ] = value
} ,
} )
* /
// set web3 defaultAccount
inpageProvider . publicConfigStore . subscribe ( function ( state ) {
web3 . eth . defaultAccount = state . selectedAddress
} )
// need to make sure we aren't affected by overlapping namespaces
// and that we dont affect the app with our namespace
// mostly a fix for web3's BigNumber if AMD's "define" is defined...
var _ _define
/ * *
* Caches reference to global define object and deletes it to
* avoid conflicts with other global define objects , such as
* AMD ' s define function
* /
function cleanContextForImports ( ) {
_ _define = global . define
try {
global . define = undefined
} catch ( _ ) {
console . warn ( 'MetaMask - global.define could not be deleted.' )
}
}
/ * *
* Restores global define object from cached reference
* /
function restoreContextAfterImports ( ) {
try {
global . define = _ _define
} catch ( _ ) {
console . warn ( 'MetaMask - global.define could not be overwritten.' )
}
}