const cp = require('child_process')
const EventEmitter = require('events')
const fs = require('fs')
const path = require('path')
const Registry = require('winreg')
const request = require('request')
const PLATFORM_MAP = {
win32: '-windows-x64.tar.gz',
darwin: '-macosx-x64.tar.gz',
linux: '-linux-x64.tar.gz'
}
class JavaGuard extends EventEmitter {
/**
* Validates that a Java binary is at least 64 bit. This makes use of the non-standard
* command line option -XshowSettings:properties. The output of this contains a property,
* sun.arch.data.model = ARCH, in which ARCH is either 32 or 64. This option is supported
* in Java 8 and 9. Since this is a non-standard option. This will resolve to true if
* the function's code throws errors. That would indicate that the option is changed or
* removed.
*
* @param {string} binaryPath Path to the root of the java binary we wish to validate.
*
* @returns {Promise.<boolean>} Resolves to false only if the test is successful and the result
* is less than 64.
*/
static _validateBinary(binaryPath){
return new Promise((resolve, reject) => {
const fBp = path.join(binaryPath, 'bin', 'java.exe')
if(fs.existsSync(fBp)){
cp.exec('"' + fBp + '" -XshowSettings:properties', (err, stdout, stderr) => {
try {
// Output is stored in stderr?
const res = stderr
const props = res.split('\n')
for(let i=0; i<props.length; i++){
if(props[i].indexOf('sun.arch.data.model') > -1){
let arch = props[i].split('=')[1].trim()
console.log(props[i].trim() + ' for ' + binaryPath)
resolve(parseInt(arch) >= 64)
}
}
// sun.arch.data.model not found?
// Disregard this test.
resolve(true)
} catch (err){
// Output format might have changed, validation cannot be completed.
// Disregard this test in that case.
resolve(true)
}
})
} else {
resolve(false)
}
})
}
/**
* Checks for the presence of the environment variable JAVA_HOME. If it exits, we will check
* to see if the value points to a path which exists. If the path exits, the path is returned.
*
* @returns {string} The path defined by JAVA_HOME, if it exists. Otherwise null.
*/
static _scanJavaHome(){
const jHome = process.env.JAVA_HOME
try {
let res = fs.existsSync(jHome)
return res ? jHome : null
} catch (err) {
// Malformed JAVA_HOME property.
return null
}
}
/**
* Scans the registry for 64-bit Java entries. The paths of each entry are added to
* a set and returned. Currently, only Java 8 (1.8) is supported.
*
* @returns {Promise.<Set.<string>>} A promise which resolves to a set of 64-bit Java root
* paths found in the registry.
*/
static _scanRegistry(){
return new Promise((resolve, reject) => {
// Keys for Java v9.0.0 and later:
// 'SOFTWARE\\JavaSoft\\JRE'
// 'SOFTWARE\\JavaSoft\\JDK'
// Forge does not yet support Java 9, therefore we do not.
let cbTracker = 0
let cbAcc = 0
// Keys for Java 1.8 and prior:
const regKeys = [
'\\SOFTWARE\\JavaSoft\\Java Runtime Environment',
'\\SOFTWARE\\JavaSoft\\Java Development Kit'
]
const candidates = new Set()
for(let i=0; i<regKeys.length; i++){
const key = new Registry({
hive: Registry.HKLM,
key: regKeys[i],
arch: 'x64'
})
key.keyExists((err, exists) => {
if(exists) {
key.keys((err, javaVers) => {
if(err){
console.error(err)
if(i === regKeys.length-1 && cbAcc === cbTracker){
resolve(candidates)
}
} else {
cbTracker += javaVers.length
if(i === regKeys.length-1 && cbTracker === cbAcc){
resolve(candidates)
} else {
for(let j=0; j<javaVers.length; j++){
const javaVer = javaVers[j]
const vKey = javaVer.key.substring(javaVer.key.lastIndexOf('\\')+1)
// Only Java 8 is supported currently.
if(parseFloat(vKey) === 1.8){
javaVer.get('JavaHome', (err, res) => {
const jHome = res.value
if(jHome.indexOf('(x86)') === -1){
candidates.add(jHome)
}
cbAcc++
if(i === regKeys.length-1 && cbAcc === cbTracker){
resolve(candidates)
}
})
} else {
cbAcc++
if(i === regKeys.length-1 && cbAcc === cbTracker){
resolve(candidates)
}
}
}
}
}
})
} else {
if(i === regKeys.length-1 && cbAcc === cbTracker){
resolve(candidates)
}
}
})
}
})
}
/**
* Attempts to find a valid x64 installation of Java on Windows machines.
* Possible paths will be pulled from the registry and the JAVA_HOME environment
* variable. The paths will be sorted with higher versions preceeding lower, and
* JREs preceeding JDKs. The binaries at the sorted paths will then be validated.
* The first validated is returned.
*
* Higher versions > Lower versions
* If versions are equal, JRE > JDK.
*
* @returns {string} The root path of a valid x64 Java installation. If none are
* found, null is returned.
*/
static async _win32Validate(){
// Get possible paths from the registry.
const pathSet = await JavaGuard._scanRegistry()
console.log(Array.from(pathSet)) // DEBUGGING
// Validate JAVA_HOME
const jHome = JavaGuard._scanJavaHome()
if(jHome != null && jHome.indexOf('(x86)') === -1){
pathSet.add(jHome)
}
// Convert path set to an array for processing.
let pathArr = Array.from(pathSet)
console.log(pathArr) // DEBUGGING
// Sorts array. Higher version numbers preceed lower. JRE preceeds JDK.
pathArr = pathArr.sort((a, b) => {
// Note that Java 9+ uses semver and that will need to be accounted for in
// the future.
const aVer = parseInt(a.split('_')[1])
const bVer = parseInt(b.split('_')[1])
if(bVer === aVer){
return a.indexOf('jdk') > -1 ? 1 : 0
} else {
return bVer - aVer
}
})
console.log(pathArr) // DEBUGGING
// Validate that the binary is actually x64.
for(let i=0; i<pathArr.length; i++) {
let res = await JavaGuard._validateBinary(pathArr[i])
if(res){
return pathArr[i]
}
}
// No suitable candidates found.
return null;
}
/**
* WIP -> get a valid x64 Java path on macOS.
*/
static async _darwinValidate(){
return null
}
/**
* WIP -> get a valid x64 Java path on linux.
*/
static async _linuxValidate(){
return null
}
static async validate(){
return await JavaGuard['_' + process.platform + 'Validate']()
}
// WIP -> Downloading Suite
static _latestJREOracle(){
const url = 'http://www.oracle.com/technetwork/java/javase/downloads/jre8-downloads-2133155.html'
const regex = /http:\/\/.+?(?=\/java)\/java\/jdk\/([0-9]+u[0-9]+)-(b[0-9]+)\/([a-f0-9]{32})?\/jre-\1/
return new Promise((resolve, reject) => {
request(url, (err, resp, body) => {
if(!err){
const arr = body.match(regex)
const verSplit = arr[1].split('u')
resolve({
uri: arr[0],
version: {
major: verSplit[0],
update: verSplit[1],
build: arr[2]
}
})
} else {
resolve(null)
}
})
})
}
_headOracleJREDlSize(url){
return new Promise((resolve, reject) => {
request.head(url, (err, resp, body) => {
if(err){
reject(err)
} else {
resolve(resp.headers['content-length'])
}
})
})
}
async _downloadOracleJRE(acceptLicense, dir){
if(!acceptLicense){
return
}
// TODO -> Complete this code. See format used in assetguard.js#510
const latestData = await JavaGuard._latestJREOracle()
const combined = latestData.uri + PLATFORM_MAP[process.platform]
const name = combined.substring(combined.lastIndexOf('/')+1)
const fDir = path.join(dir, name)
const opts = {
url: combined,
headers: {
'Cookie': 'oraclelicense=accept-securebackup-cookie'
}
}
const req = request(opts)
let writeStream = fs.createWriteStream(fDir)
req.pipe(writeStream)
req.resume()
}
_downloadJava(dir){
this._downloadOracleJRE(true, dir)
}
}
async function test(){
//console.log(await JavaGuard.validate())
const g = new JavaGuard()
g._downloadJava('C:\\Users\\Asus\\Desktop\\LauncherElectron\\target\\')
//console.log(JSON.stringify(await _latestJREOracle()))
}
test()
module.exports = {
JavaGuard
}