electron/lib/browser/rpc-server.js

363 lines
12 KiB
JavaScript

'use strict'
const electron = require('electron')
const v8Util = process.atomBinding('v8_util')
const {ipcMain} = electron
const {createIDWeakMap} = process.atomBinding('id_weak_map')
const objectsRegistry = require('./objects-registry')
// The internal properties of Function.
const FUNCTION_PROPERTIES = [
'length', 'name', 'arguments', 'caller', 'prototype'
]
// The remote functions in renderer processes.
// id => Function
let rendererFunctions = createIDWeakMap()
// Merge two IDs together.
let mergeIds = function (webContentsId, metaId) {
const PADDING_BITS = 20
if ((webContentsId << PADDING_BITS) < 0) {
throw new Error(`webContents ID is too large: ${webContentsId}`)
} else if (metaId > (1 << PADDING_BITS)) {
throw new Error(`Object ID is too large: ${metaId}`)
}
return (webContentsId << PADDING_BITS) + metaId
}
// Return the description of object's members:
let getObjectMembers = function (object) {
let names = Object.getOwnPropertyNames(object)
// For Function, we should not override following properties even though they
// are "own" properties.
if (typeof object === 'function') {
names = names.filter((name) => {
return !FUNCTION_PROPERTIES.includes(name)
})
}
// Map properties to descriptors.
return names.map((name) => {
let descriptor = Object.getOwnPropertyDescriptor(object, name)
let member = {name, enumerable: descriptor.enumerable, writable: false}
if (descriptor.get === undefined && typeof object[name] === 'function') {
member.type = 'method'
} else {
if (descriptor.set || descriptor.writable) member.writable = true
member.type = 'get'
}
return member
})
}
// Return the description of object's prototype.
let getObjectPrototype = function (object) {
let proto = Object.getPrototypeOf(object)
if (proto === null || proto === Object.prototype) return null
return {
members: getObjectMembers(proto),
proto: getObjectPrototype(proto)
}
}
// Convert a real value into meta data.
let valueToMeta = function (sender, value, optimizeSimpleObject = false) {
// Determine the type of value.
let meta = { type: typeof value }
if (meta.type === 'object') {
// Recognize certain types of objects.
if (value === null) {
meta.type = 'value'
} else if (Buffer.isBuffer(value)) {
meta.type = 'buffer'
} else if (Array.isArray(value)) {
meta.type = 'array'
} else if (value instanceof Error) {
meta.type = 'error'
} else if (value instanceof Date) {
meta.type = 'date'
} else if (value.constructor != null && value.constructor.name === 'Promise') {
meta.type = 'promise'
} else if (value.hasOwnProperty('callee') && value.length != null) {
// Treat the arguments object as array.
meta.type = 'array'
} else if (optimizeSimpleObject && v8Util.getHiddenValue(value, 'simple')) {
// Treat simple objects as value.
meta.type = 'value'
}
}
// Fill the meta object according to value's type.
if (meta.type === 'array') {
meta.members = value.map((el) => valueToMeta(sender, el))
} else if (meta.type === 'object' || meta.type === 'function') {
meta.name = value.constructor ? value.constructor.name : ''
// Reference the original value if it's an object, because when it's
// passed to renderer we would assume the renderer keeps a reference of
// it.
meta.id = objectsRegistry.add(sender, value)
meta.members = getObjectMembers(value)
meta.proto = getObjectPrototype(value)
} else if (meta.type === 'buffer') {
meta.value = Array.prototype.slice.call(value, 0)
} else if (meta.type === 'promise') {
meta.then = valueToMeta(sender, function (v) { value.then(v) })
} else if (meta.type === 'error') {
meta.members = plainObjectToMeta(value)
// Error.name is not part of own properties.
meta.members.push({
name: 'name',
value: value.name
})
} else if (meta.type === 'date') {
meta.value = value.getTime()
} else {
meta.type = 'value'
meta.value = value
}
return meta
}
// Convert object to meta by value.
var plainObjectToMeta = function (obj) {
return Object.getOwnPropertyNames(obj).map(function (name) {
return {
name: name,
value: obj[name]
}
})
}
// Convert Error into meta data.
var exceptionToMeta = function (error) {
return {
type: 'exception',
message: error.message,
stack: error.stack || error
}
}
// Convert array of meta data from renderer into array of real values.
var unwrapArgs = function (sender, args) {
var metaToValue
metaToValue = function (meta) {
var i, len, member, ref, returnValue
switch (meta.type) {
case 'value':
return meta.value
case 'remote-object':
return objectsRegistry.get(meta.id)
case 'array':
return unwrapArgs(sender, meta.value)
case 'buffer':
return new Buffer(meta.value)
case 'date':
return new Date(meta.value)
case 'promise':
return Promise.resolve({
then: metaToValue(meta.then)
})
case 'object': {
let ret = {}
Object.defineProperty(ret.constructor, 'name', { value: meta.name })
ref = meta.members
for (i = 0, len = ref.length; i < len; i++) {
member = ref[i]
ret[member.name] = metaToValue(member.value)
}
return ret
}
case 'function-with-return-value':
returnValue = metaToValue(meta.value)
return function () {
return returnValue
}
case 'function': {
// Merge webContentsId and meta.id, since meta.id can be the same in
// different webContents.
const webContentsId = sender.getId()
const objectId = mergeIds(webContentsId, meta.id)
// Cache the callbacks in renderer.
if (rendererFunctions.has(objectId)) {
return rendererFunctions.get(objectId)
}
let callIntoRenderer = function (...args) {
if (!sender.isDestroyed() && webContentsId === sender.getId()) {
sender.send('ELECTRON_RENDERER_CALLBACK', meta.id, valueToMeta(sender, args))
} else {
throw new Error(`Attempting to call a function in a renderer window that has been closed or released. Function provided here: ${meta.location}.`)
}
}
v8Util.setRemoteCallbackFreer(callIntoRenderer, meta.id, sender)
rendererFunctions.set(objectId, callIntoRenderer)
return callIntoRenderer
}
default:
throw new TypeError(`Unknown type: ${meta.type}`)
}
}
return args.map(metaToValue)
}
// Call a function and send reply asynchronously if it's a an asynchronous
// style function and the caller didn't pass a callback.
var callFunction = function (event, func, caller, args) {
var funcMarkedAsync, funcName, funcPassedCallback, ref, ret
funcMarkedAsync = v8Util.getHiddenValue(func, 'asynchronous')
funcPassedCallback = typeof args[args.length - 1] === 'function'
try {
if (funcMarkedAsync && !funcPassedCallback) {
args.push(function (ret) {
event.returnValue = valueToMeta(event.sender, ret, true)
})
return func.apply(caller, args)
} else {
ret = func.apply(caller, args)
event.returnValue = valueToMeta(event.sender, ret, true)
}
} catch (error) {
// Catch functions thrown further down in function invocation and wrap
// them with the function name so it's easier to trace things like
// `Error processing argument -1.`
funcName = ((ref = func.name) != null) ? ref : 'anonymous'
throw new Error(`Could not call remote function '${funcName}'. Check that the function signature is correct. Underlying error: ${error.message}`)
}
}
ipcMain.on('ELECTRON_BROWSER_REQUIRE', function (event, module) {
try {
event.returnValue = valueToMeta(event.sender, process.mainModule.require(module))
} catch (error) {
event.returnValue = exceptionToMeta(error)
}
})
ipcMain.on('ELECTRON_BROWSER_GET_BUILTIN', function (event, module) {
try {
event.returnValue = valueToMeta(event.sender, electron[module])
} catch (error) {
event.returnValue = exceptionToMeta(error)
}
})
ipcMain.on('ELECTRON_BROWSER_GLOBAL', function (event, name) {
try {
event.returnValue = valueToMeta(event.sender, global[name])
} catch (error) {
event.returnValue = exceptionToMeta(error)
}
})
ipcMain.on('ELECTRON_BROWSER_CURRENT_WINDOW', function (event) {
try {
event.returnValue = valueToMeta(event.sender, event.sender.getOwnerBrowserWindow())
} catch (error) {
event.returnValue = exceptionToMeta(error)
}
})
ipcMain.on('ELECTRON_BROWSER_CURRENT_WEB_CONTENTS', function (event) {
event.returnValue = valueToMeta(event.sender, event.sender)
})
ipcMain.on('ELECTRON_BROWSER_CONSTRUCTOR', function (event, id, args) {
try {
args = unwrapArgs(event.sender, args)
let constructor = objectsRegistry.get(id)
// Call new with array of arguments.
// http://stackoverflow.com/questions/1606797/use-of-apply-with-new-operator-is-this-possible
let obj = new (Function.prototype.bind.apply(constructor, [null].concat(args)))
event.returnValue = valueToMeta(event.sender, obj)
} catch (error) {
event.returnValue = exceptionToMeta(error)
}
})
ipcMain.on('ELECTRON_BROWSER_FUNCTION_CALL', function (event, id, args) {
try {
args = unwrapArgs(event.sender, args)
let func = objectsRegistry.get(id)
return callFunction(event, func, global, args)
} catch (error) {
event.returnValue = exceptionToMeta(error)
}
})
ipcMain.on('ELECTRON_BROWSER_MEMBER_CONSTRUCTOR', function (event, id, method, args) {
try {
args = unwrapArgs(event.sender, args)
let constructor = objectsRegistry.get(id)[method]
// Call new with array of arguments.
let obj = new (Function.prototype.bind.apply(constructor, [null].concat(args)))
event.returnValue = valueToMeta(event.sender, obj)
} catch (error) {
event.returnValue = exceptionToMeta(error)
}
})
ipcMain.on('ELECTRON_BROWSER_MEMBER_CALL', function (event, id, method, args) {
try {
args = unwrapArgs(event.sender, args)
let obj = objectsRegistry.get(id)
return callFunction(event, obj[method], obj, args)
} catch (error) {
event.returnValue = exceptionToMeta(error)
}
})
ipcMain.on('ELECTRON_BROWSER_MEMBER_SET', function (event, id, name, value) {
try {
let obj = objectsRegistry.get(id)
obj[name] = value
event.returnValue = null
} catch (error) {
event.returnValue = exceptionToMeta(error)
}
})
ipcMain.on('ELECTRON_BROWSER_MEMBER_GET', function (event, id, name) {
try {
let obj = objectsRegistry.get(id)
event.returnValue = valueToMeta(event.sender, obj[name])
} catch (error) {
event.returnValue = exceptionToMeta(error)
}
})
ipcMain.on('ELECTRON_BROWSER_DEREFERENCE', function (event, id) {
return objectsRegistry.remove(event.sender.getId(), id)
})
ipcMain.on('ELECTRON_BROWSER_GUEST_WEB_CONTENTS', function (event, guestInstanceId) {
try {
let guestViewManager = require('./guest-view-manager')
event.returnValue = valueToMeta(event.sender, guestViewManager.getGuest(guestInstanceId))
} catch (error) {
event.returnValue = exceptionToMeta(error)
}
})
ipcMain.on('ELECTRON_BROWSER_ASYNC_CALL_TO_GUEST_VIEW', function (event, requestId, guestInstanceId, method, ...args) {
try {
let guestViewManager = require('./guest-view-manager')
let guest = guestViewManager.getGuest(guestInstanceId)
if (requestId) {
const responseCallback = function (result) {
event.sender.send(`ELECTRON_RENDERER_ASYNC_CALL_TO_GUEST_VIEW_RESPONSE_${requestId}`, result)
}
args.push(responseCallback)
}
guest[method].apply(guest, args)
} catch (error) {
event.returnValue = exceptionToMeta(error)
}
})