app.js - compiler-explorer - Rivoreo Source Code Repositories

 #!/usr/bin/env node

 // Copyright (c) 2012-2017, Matt Godbolt
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are met:
 //
 //     * Redistributions of source code must retain the above copyright notice,
 //       this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above copyright
 //       notice, this list of conditions and the following disclaimer in the
 //       documentation and/or other materials provided with the distribution.
 //
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 // ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 // LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 // CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 // SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 // CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 // POSSIBILITY OF SUCH DAMAGE.

 // Initialise options and properties. Don't load any handlers here; they
 // may need an initialised properties library.
 const nopt = require('nopt'),
     os = require('os'),
     props = require('./lib/properties'),
     child_process = require('child_process'),
     path = require('path'),
     fs = require('fs-extra'),
     http = require('http'),
     https = require('https'),
     url = require('url'),
     _ = require('underscore-node'),
     utils = require('./lib/utils'),
     express = require('express'),
     logger = require('./lib/logger').logger,
     Raven = require('raven');

 // Parse arguments from command line 'node ./app.js args...'
 var opts = nopt({
     'env': [String, Array],
     'rootDir': [String],
     'language': [String],
     'host': [String],
     'port': [Number],
     'propDebug': [Boolean],
     'debug': [Boolean],
     'static': [String],
     'archivedVersions': [String],
     'noRemoteFetch': [Boolean],
     'tmpDir': [String],
     'wsl': [Boolean]
 });

 if (opts.debug) logger.level = 'debug';

 // AP: Detect if we're running under Windows Subsystem for Linux. Temporary modification
 // of process.env is allowed: https://nodejs.org/api/process.html#process_process_env
 if (child_process.execSync('uname -a').toString().indexOf('Microsoft') > -1)
     process.env.wsl = true;

 // AP: Allow setting of tmpDir (used in lib/base-compiler.js & lib/exec.js) through opts.
 // WSL requires a directory on a Windows volume. Set that to Windows %TEMP% if no tmpDir supplied.
 // If a tempDir is supplied then assume that it will work for WSL processes as well.
 if (opts.tmpDir) {
     process.env.tmpDir = opts.tmpDir;
     process.env.winTmp = opts.tmpDir;
 }
 else if (process.env.wsl) {
     // Dec 2017 preview builds of WSL include /bin/wslpath; do the parsing work for now.
     // Parsing example %TEMP% is C:\Users\apardoe\AppData\Local\Temp
     var windowsTemp = child_process.execSync('cmd.exe /c echo %TEMP%').toString().replace(/\\/g, "/");
     var driveLetter = windowsTemp.substring(0, 1).toLowerCase();
     var directoryPath = windowsTemp.substring(2).trim();
     process.env.winTmp = path.join("/mnt", driveLetter, directoryPath);
 }

 // Set default values for omitted arguments
 var rootDir = opts.rootDir || './etc';
 var language = opts.language || "C++";
 var env = opts.env || ['dev'];
 var hostname = opts.host;
 var port = opts.port || 10240;
 var staticDir = opts.static || 'static';
 var archivedVersions = opts.archivedVersions;
 var gitReleaseName = "";
 var versionedRootPrefix = "";
 // Use the canned git_hash if provided
 if (opts.static && fs.existsSync(opts.static + "/git_hash")) {
     gitReleaseName = fs.readFileSync(opts.static + "/git_hash").toString().trim();
 } else if (fs.existsSync('.git/')) { // Just if we have been cloned and not downloaded (Thanks David!)
     gitReleaseName = child_process.execSync('git rev-parse HEAD').toString().trim();
 }
 if (opts.static && fs.existsSync(opts.static + '/v/' + gitReleaseName))
     versionedRootPrefix = "v/" + gitReleaseName + "/";
 // Don't treat @ in paths as remote adresses
 var fetchCompilersFromRemote = !opts.noRemoteFetch;

 var propHierarchy = _.flatten([
     'defaults',
     env,
     language,
     _.map(env, function (e) {
         return e + '.' + process.platform;
     }),
     process.platform,
     os.hostname(),
     'local']);
 logger.info("properties hierarchy: " + propHierarchy.join(', '));

 // Propagate debug mode if need be
 if (opts.propDebug) props.setDebug(true);

 // *All* files in config dir are parsed
 props.initialize(rootDir + '/config', propHierarchy);

 // Now load up our libraries.
 const aws = require('./lib/aws'),
     google = require('./lib/google');

 // Instantiate a function to access records concerning "compiler-explorer"
 // in hidden object props.properties
 var gccProps = props.propsFor("compiler-explorer");

 // Instantiate a function to access records concerning the chosen language
 // in hidden object props.properties
 var compilerPropsFunc = props.propsFor(language.toLowerCase());

 // If no option for the compiler ... use gcc's options (??)
 function compilerProps(property, defaultValue) {
     // My kingdom for ccs... [see Matt's github page]
     var forCompiler = compilerPropsFunc(property, undefined);
     if (forCompiler !== undefined) return forCompiler;
     return gccProps(property, defaultValue);
 }

 var staticMaxAgeSecs = gccProps('staticMaxAgeSecs', 0);
 let extraBodyClass = gccProps('extraBodyClass', '');

 function staticHeaders(res) {
     if (staticMaxAgeSecs) {
         res.setHeader('Cache-Control', 'public, max-age=' + staticMaxAgeSecs + ', must-revalidate');
     }
 }

 var awsProps = props.propsFor("aws");
 var awsPoller = null;

 function awsInstances() {
     if (!awsPoller) awsPoller = new aws.InstanceFetcher(awsProps);
     return awsPoller.getInstances();
 }

 // function to load internal binaries (i.e. lib/source/*.js)
 function loadSources() {
     var sourcesDir = "lib/sources";
     return fs.readdirSync(sourcesDir)
         .filter(function (file) {
             return file.match(/.*\.js$/);
         })
         .map(function (file) {
             return require("./" + path.join(sourcesDir, file));
         });
 }

 const fileSources = loadSources();
 const clientOptionsHandler = new ClientOptionsHandler(fileSources);
 const CompileHandler = require('./lib/handlers/compile').Handler;
 const compileHandler = new CompileHandler(gccProps, compilerProps);
 const ApiHandler = require('./lib/handlers/api').Handler;
 const apiHandler = new ApiHandler(compileHandler);
 const SourceHandler = require('./lib/handlers/source').Handler;
 const sourceHandler = new SourceHandler(fileSources, staticHeaders);

 function ClientOptionsHandler(fileSources) {
     const sources = _.sortBy(fileSources.map(source => ({name: source.name, urlpart: source.urlpart})), "name");
     const languages = _.compact(_.map(gccProps("languages", '').split(':'), thing => {
         if (!thing) return null;
         var splat = thing.split("=");
         return {language: splat[0], url: splat[1]};
     }));
     const supportsBinary = !!compilerProps("supportsBinary", true);
     const supportsExecute = supportsBinary && !!compilerProps("supportsExecute", true);
     const libs = {};

     const baseLibs = compilerProps("libs");

     if (baseLibs) {
         _.each(baseLibs.split(':'), function (lib) {
             libs[lib] = {name: compilerProps('libs.' + lib + '.name')};
             libs[lib].versions = {};
             const listedVersions = compilerProps("libs." + lib + '.versions');
             if (listedVersions) {
                 _.each(listedVersions.split(':'), function (version) {
                     libs[lib].versions[version] = {};
                     libs[lib].versions[version].version = compilerProps("libs." + lib + '.versions.' + version + '.version');
                     libs[lib].versions[version].path = [];
                     var listedIncludes = compilerProps("libs." + lib + '.versions.' + version + '.path');
                     if (listedIncludes) {
                         _.each(listedIncludes.split(':'), function (path) {
                             libs[lib].versions[version].path.push(path);
                         });
                     } else {
                         logger.warn("No paths found for " + lib + " version " + version);
                     }
                 });
             } else {
                 logger.warn("No versions found for " + lib + " library");
             }
         });
     }
     const options = {
         googleAnalyticsAccount: gccProps('clientGoogleAnalyticsAccount', 'UA-55180-6'),
         googleAnalyticsEnabled: gccProps('clientGoogleAnalyticsEnabled', false),
         sharingEnabled: gccProps('clientSharingEnabled', true),
         githubEnabled: gccProps('clientGitHubRibbonEnabled', true),
         gapiKey: gccProps('googleApiKey', ''),
         googleShortLinkRewrite: gccProps('googleShortLinkRewrite', '').split('|'),
         defaultSource: gccProps('defaultSource', ''),
         language: language,
         compilers: [],
         libs: libs,
         sourceExtension: compilerProps('compileFilename').split('.', 2)[1],
         defaultCompiler: compilerProps('defaultCompiler', ''),
         compileOptions: compilerProps('defaultOptions', ''),
         supportsBinary: supportsBinary,
         supportsExecute: supportsExecute,
         languages: languages,
         sources: sources,
         raven: gccProps('ravenUrl', ''),
         release: gitReleaseName,
         environment: env,
         localStoragePrefix: gccProps('localStoragePrefix'),
         cvCompilerCountMax: gccProps('cvCompilerCountMax', 6),
         defaultFontScale: gccProps('defaultFontScale', 1.0)
     };
     this.setCompilers = function (compilers) {
         options.compilers = compilers;
     };
     this.setCompilers([]);
     this.handler = function getClientOptions(req, res) {
         res.set('Content-Type', 'application/json');
         staticHeaders(res);
         res.end(JSON.stringify(options));
     };
     this.get = function () {
         return options;
     };
 }

 function retryPromise(promiseFunc, name, maxFails, retryMs) {
     return new Promise(function (resolve, reject) {
         var fails = 0;

         function doit() {
             var promise = promiseFunc();
             promise.then(function (arg) {
                 resolve(arg);
             }, function (e) {
                 fails++;
                 if (fails < maxFails) {
                     logger.warn("Failed " + name + " : " + e + ", retrying");
                     setTimeout(doit, retryMs);
                 } else {
                     logger.error("Too many retries for " + name + " : " + e);
                     reject(e);
                 }
             });
         }

         doit();
     });
 }

 function findCompilers() {
     var exes = compilerProps("compilers", "/usr/bin/g++").split(":");
     var ndk = compilerProps('androidNdk');
     if (ndk) {
         var toolchains = fs.readdirSync(ndk + "/toolchains");
         toolchains.forEach(function (v, i, a) {
             var path = ndk + "/toolchains/" + v + "/prebuilt/linux-x86_64/bin/";
             if (fs.existsSync(path)) {
                 var cc = fs.readdirSync(path).filter(function (filename) {
                     return filename.indexOf("g++") !== -1;
                 });
                 a[i] = path + cc[0];
             } else {
                 a[i] = null;
             }
         });
         toolchains = toolchains.filter(function (x) {
             return x !== null;
         });
         exes.push.apply(exes, toolchains);
     }

     function fetchRemote(host, port, props) {
         logger.info("Fetching compilers from remote source " + host + ":" + port);
         return retryPromise(function () {
                 return new Promise(function (resolve, reject) {
                     var request = http.get({
                         hostname: host,
                         port: port,
                         path: "/api/compilers",
                         headers: {
                             'Accept': 'application/json'
                         }
                     }, function (res) {
                         var str = '';
                         res.on('data', function (chunk) {
                             str += chunk;
                         });
                         res.on('end', function () {
                             var compilers = JSON.parse(str).map(function (compiler) {
                                 compiler.exe = null;
                                 compiler.remote = "http://" + host + ":" + port;
                                 return compiler;
                             });
                             resolve(compilers);
                         });
                     }).on('error', function (e) {
                         reject(e);
                     }).on('timeout', function () {
                         reject("timeout");
                     });
                     request.setTimeout(awsProps('proxyTimeout', 1000));
                 });
             },
             host + ":" + port,
             props('proxyRetries', 5),
             props('proxyRetryMs', 500))
             .catch(function () {
                 logger.warn("Unable to contact " + host + ":" + port + "; skipping");
                 return [];
             });
     }

     function fetchAws() {
         logger.info("Fetching instances from AWS");
         return awsInstances().then(function (instances) {
             return Promise.all(instances.map(function (instance) {
                 logger.info("Checking instance " + instance.InstanceId);
                 var address = instance.PrivateDnsName;
                 if (awsProps("externalTestMode", false)) {
                     address = instance.PublicDnsName;
                 }
                 return fetchRemote(address, port, awsProps);
             }));
         });
     }

     function compilerConfigFor(name, parentProps) {
         const base = "compiler." + name,
             exe = compilerProps(base + ".exe", name);

         function props(name, def) {
             return parentProps(base + "." + name, parentProps(name, def));
         }

         var supportsBinary = !!props("supportsBinary", true);
         var supportsExecute = supportsBinary && !!props("supportsExecute", true);
         var compilerInfo = {
             id: name,
             exe: exe,
             name: props("name", name),
             alias: props("alias"),
             options: props("options"),
             versionFlag: props("versionFlag"),
             versionRe: props("versionRe"),
             compilerType: props("compilerType", ""),
             demangler: props("demangler", ""),
             objdumper: props("objdumper", ""),
             intelAsm: props("intelAsm", ""),
             needsMulti: !!props("needsMulti", true),
             supportsBinary: supportsBinary,
             supportsExecute: supportsExecute,
             postProcess: props("postProcess", "").split("|")
         };
         logger.info("Found compiler", compilerInfo);
         return Promise.resolve(compilerInfo);
     }

     function recurseGetCompilers(name, parentProps) {
         if (fetchCompilersFromRemote && name.indexOf("@") !== -1) {
             var bits = name.split("@");
             var host = bits[0];
             var port = parseInt(bits[1]);
             return fetchRemote(host, port, gccProps);
         }
         if (name.indexOf("&") === 0) {
             var groupName = name.substr(1);

             var props = function (name, def) {
                 if (name === "group") {
                     return groupName;
                 }
                 return compilerProps("group." + groupName + "." + name, parentProps(name, def));
             };

             var exes = props('compilers', '').split(":");
             logger.info("Processing compilers from group " + groupName);
             return Promise.all(exes.map(function (compiler) {
                 return recurseGetCompilers(compiler, props);
             }));
         }
         if (name === "AWS") return fetchAws();
         return compilerConfigFor(name, parentProps);
     }

     return Promise.all(exes.map(compiler => recurseGetCompilers(compiler, compilerProps)))
         .then(_.flatten)
         .then(compilers => compileHandler.setCompilers(compilers))
         .then(compilers => _.sortBy(_.compact(compilers), "name"));
 }

 function shortUrlHandler(req, res, next) {
     const resolver = new google.ShortLinkResolver(aws.getConfig('googleApiKey'));
     const bits = req.url.split("/");
     if (bits.length !== 2 || req.method !== "GET") return next();
     const googleUrl = `http://goo.gl/${encodeURIComponent(bits[1])}`;
     resolver.resolve(googleUrl)
         .then(resultObj => {
             var parsed = url.parse(resultObj.longUrl);
             var allowedRe = new RegExp(gccProps('allowedShortUrlHostRe'));
             if (parsed.host.match(allowedRe) === null) {
                 logger.warn("Denied access to short URL " + bits[1] + " - linked to " + resultObj.longUrl);
                 return next();
             }
             res.writeHead(301, {
                 Location: resultObj.id,
                 'Cache-Control': 'public'
             });
             res.end();
         })
         .catch(e => {
             logger.error(`Failed to expand ${googleUrl} - ${e}`);
             next();
         });
 }

 Promise.all([findCompilers(), aws.initConfig(awsProps)])
     .then(function (args) {
         let compilers = args[0];
         var prevCompilers;

         const ravenPrivateEndpoint = aws.getConfig('ravenPrivateEndpoint');
         if (ravenPrivateEndpoint) {
             Raven.config(ravenPrivateEndpoint, {
                 release: gitReleaseName,
                 environment: env
             }).install();
             logger.info("Configured with raven endpoint", ravenPrivateEndpoint);
         } else {
             Raven.config(false).install();
         }

         const newRelicLicense = aws.getConfig('newRelicLicense');
         if (newRelicLicense) {
             process.env.NEW_RELIC_NO_CONFIG_FILE = true;
             process.env.NEW_RELIC_APP_NAME = 'Compiler Explorer';
             process.env.NEW_RELIC_LICENSE_KEY = newRelicLicense;
             process.env.NEW_RELIC_LABELS = 'Language:' + language;
             require('newrelic');
             logger.info('New relic configured with license', newRelicLicense);
         }

         function onCompilerChange(compilers) {
             if (JSON.stringify(prevCompilers) === JSON.stringify(compilers)) {
                 return;
             }
             logger.info("Compilers:", compilers);
             if (compilers.length === 0) {
                 logger.error("#### No compilers found: no compilation will be done!");
             }
             prevCompilers = compilers;
             clientOptionsHandler.setCompilers(compilers);
             apiHandler.setCompilers(compilers);
         }

         onCompilerChange(compilers);

         var rescanCompilerSecs = gccProps('rescanCompilerSecs', 0);
         if (rescanCompilerSecs) {
             logger.info("Rescanning compilers every " + rescanCompilerSecs + "secs");
             setInterval(function () {
                 findCompilers().then(onCompilerChange);
             }, rescanCompilerSecs * 1000);
         }

         var webServer = express(),
             sFavicon = require('serve-favicon'),
             bodyParser = require('body-parser'),
             morgan = require('morgan'),
             compression = require('compression'),
             restreamer = require('./lib/restreamer');

         logger.info("=======================================");
         logger.info("Listening on http://" + (hostname || 'localhost') + ":" + port + "/");
         logger.info("  serving static files from '" + staticDir + "'");
         if (gitReleaseName) logger.info("  git release " + gitReleaseName);

         function renderConfig(extra) {
             var options = _.extend(extra, clientOptionsHandler.get());
             options.compilerExplorerOptions = JSON.stringify(options);
             options.root = versionedRootPrefix;
             options.extraBodyClass = extraBodyClass;
             return options;
         }

         const embeddedHandler = function (req, res) {
             staticHeaders(res);
             res.render('embed', renderConfig({embedded: true}));
         };
         const healthCheck = require('./lib/handlers/health-check');
         webServer
             .use(Raven.requestHandler())
             .set('trust proxy', true)
             .set('view engine', 'pug')
             .use('/healthcheck', new healthCheck.HealthCheckHandler().handle) // before morgan so healthchecks aren't logged
             .use(morgan('combined', {stream: logger.stream}))
             .use(compression())
             .get('/', function (req, res) {
                 staticHeaders(res);
                 res.render('index', renderConfig({embedded: false}));
             })
             .get('/e', embeddedHandler)
             .get('/embed.html', embeddedHandler) // legacy. not a 301 to prevent any redirect loops between old e links and embed.html
             .get('/embed-ro', function (req, res) {
                 staticHeaders(res);
                 res.render('embed', renderConfig({embedded: true, readOnly: true}));
             })
             .get('/robots.txt', function (req, res) {
                 staticHeaders(res);
                 res.end('User-agent: *\nSitemap: https://godbolt.org/sitemap.xml');
             })
             .get('/sitemap.xml', function (req, res) {
                 staticHeaders(res);
                 res.set('Content-Type', 'application/xml');
                 res.render('sitemap');
             })
             .use(sFavicon(staticDir + '/favicon.ico'))
             .use('/v', express.static(staticDir + '/v', {maxAge: Infinity, index: false}))
             .use(express.static(staticDir, {maxAge: staticMaxAgeSecs * 1000}));
         if (archivedVersions) {
             // The archived versions directory is used to serve "old" versioned data during updates. It's expected
             // to contain all the SHA-hashed directories from previous versions of Compiler Explorer.
             logger.info("  serving archived versions from", archivedVersions);
             webServer.use('/v', express.static(archivedVersions, {maxAge: Infinity, index: false}));
         }
         webServer
             .use(bodyParser.json({limit: gccProps('bodyParserLimit', '1mb')}))
             .use(bodyParser.text({
                 limit: gccProps('bodyParserLimit', '1mb'), type: function () {
                     return true;
                 }
             }))
             .use(restreamer())
             .get('/client-options.json', clientOptionsHandler.handler)
             .use('/source', sourceHandler.handle.bind(sourceHandler))
             .use('/api', apiHandler.handle)
             .use('/g', shortUrlHandler);
         logger.info("=======================================");

         webServer.use(Raven.errorHandler());

         webServer.on('error', function (err) {
             logger.error('Caught error:', err, "(in web error handler; continuing)");
         });

         webServer.listen(port, hostname);
     })
     .catch(function (err) {
         logger.error("Promise error:", err, "(shutting down)");
         process.exit(1);
     });
	#!/usr/bin/env node

	// Copyright (c) 2012-2017, Matt Godbolt
	// All rights reserved.
	//
	// Redistribution and use in source and binary forms, with or without
	// modification, are permitted provided that the following conditions are met:
	//
	// * Redistributions of source code must retain the above copyright notice,
	// this list of conditions and the following disclaimer.
	// * Redistributions in binary form must reproduce the above copyright
	// notice, this list of conditions and the following disclaimer in the
	// documentation and/or other materials provided with the distribution.
	//
	// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
	// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
	// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
	// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
	// POSSIBILITY OF SUCH DAMAGE.

	// Initialise options and properties. Don't load any handlers here; they
	// may need an initialised properties library.
	const nopt = require('nopt'),
	os = require('os'),
	props = require('./lib/properties'),
	child_process = require('child_process'),
	path = require('path'),
	fs = require('fs-extra'),
	http = require('http'),
	https = require('https'),
	url = require('url'),
	_ = require('underscore-node'),
	utils = require('./lib/utils'),
	express = require('express'),
	logger = require('./lib/logger').logger,
	Raven = require('raven');

	// Parse arguments from command line 'node ./app.js args...'
	var opts = nopt({
	'env': [String, Array],
	'rootDir': [String],
	'language': [String],
	'host': [String],
	'port': [Number],
	'propDebug': [Boolean],
	'debug': [Boolean],
	'static': [String],
	'archivedVersions': [String],
	'noRemoteFetch': [Boolean],
	'tmpDir': [String],
	'wsl': [Boolean]
	});

	if (opts.debug) logger.level = 'debug';

	// AP: Detect if we're running under Windows Subsystem for Linux. Temporary modification
	// of process.env is allowed: https://nodejs.org/api/process.html#process_process_env
	if (child_process.execSync('uname -a').toString().indexOf('Microsoft') > -1)
	process.env.wsl = true;

	// AP: Allow setting of tmpDir (used in lib/base-compiler.js & lib/exec.js) through opts.
	// WSL requires a directory on a Windows volume. Set that to Windows %TEMP% if no tmpDir supplied.
	// If a tempDir is supplied then assume that it will work for WSL processes as well.
	if (opts.tmpDir) {
	process.env.tmpDir = opts.tmpDir;
	process.env.winTmp = opts.tmpDir;
	}
	else if (process.env.wsl) {
	// Dec 2017 preview builds of WSL include /bin/wslpath; do the parsing work for now.
	// Parsing example %TEMP% is C:\Users\apardoe\AppData\Local\Temp
	var windowsTemp = child_process.execSync('cmd.exe /c echo %TEMP%').toString().replace(/\\/g, "/");
	var driveLetter = windowsTemp.substring(0, 1).toLowerCase();
	var directoryPath = windowsTemp.substring(2).trim();
	process.env.winTmp = path.join("/mnt", driveLetter, directoryPath);
	}

	// Set default values for omitted arguments
	var rootDir = opts.rootDir \|\| './etc';
	var language = opts.language \|\| "C++";
	var env = opts.env \|\| ['dev'];
	var hostname = opts.host;
	var port = opts.port \|\| 10240;
	var staticDir = opts.static \|\| 'static';
	var archivedVersions = opts.archivedVersions;
	var gitReleaseName = "";
	var versionedRootPrefix = "";
	// Use the canned git_hash if provided
	if (opts.static && fs.existsSync(opts.static + "/git_hash")) {
	gitReleaseName = fs.readFileSync(opts.static + "/git_hash").toString().trim();
	} else if (fs.existsSync('.git/')) { // Just if we have been cloned and not downloaded (Thanks David!)
	gitReleaseName = child_process.execSync('git rev-parse HEAD').toString().trim();
	}
	if (opts.static && fs.existsSync(opts.static + '/v/' + gitReleaseName))
	versionedRootPrefix = "v/" + gitReleaseName + "/";
	// Don't treat @ in paths as remote adresses
	var fetchCompilersFromRemote = !opts.noRemoteFetch;

	var propHierarchy = _.flatten([
	'defaults',
	env,
	language,
	_.map(env, function (e) {
	return e + '.' + process.platform;
	}),
	process.platform,
	os.hostname(),
	'local']);
	logger.info("properties hierarchy: " + propHierarchy.join(', '));

	// Propagate debug mode if need be
	if (opts.propDebug) props.setDebug(true);

	// All files in config dir are parsed
	props.initialize(rootDir + '/config', propHierarchy);

	// Now load up our libraries.
	const aws = require('./lib/aws'),
	google = require('./lib/google');

	// Instantiate a function to access records concerning "compiler-explorer"
	// in hidden object props.properties
	var gccProps = props.propsFor("compiler-explorer");

	// Instantiate a function to access records concerning the chosen language
	// in hidden object props.properties
	var compilerPropsFunc = props.propsFor(language.toLowerCase());

	// If no option for the compiler ... use gcc's options (??)
	function compilerProps(property, defaultValue) {
	// My kingdom for ccs... [see Matt's github page]
	var forCompiler = compilerPropsFunc(property, undefined);
	if (forCompiler !== undefined) return forCompiler;
	return gccProps(property, defaultValue);
	}

	var staticMaxAgeSecs = gccProps('staticMaxAgeSecs', 0);
	let extraBodyClass = gccProps('extraBodyClass', '');

	function staticHeaders(res) {
	if (staticMaxAgeSecs) {
	res.setHeader('Cache-Control', 'public, max-age=' + staticMaxAgeSecs + ', must-revalidate');
	}
	}

	var awsProps = props.propsFor("aws");
	var awsPoller = null;

	function awsInstances() {
	if (!awsPoller) awsPoller = new aws.InstanceFetcher(awsProps);
	return awsPoller.getInstances();
	}

	// function to load internal binaries (i.e. lib/source/*.js)
	function loadSources() {
	var sourcesDir = "lib/sources";
	return fs.readdirSync(sourcesDir)
	.filter(function (file) {
	return file.match(/.*\.js$/);
	})
	.map(function (file) {
	return require("./" + path.join(sourcesDir, file));
	});
	}

	const fileSources = loadSources();
	const clientOptionsHandler = new ClientOptionsHandler(fileSources);
	const CompileHandler = require('./lib/handlers/compile').Handler;
	const compileHandler = new CompileHandler(gccProps, compilerProps);
	const ApiHandler = require('./lib/handlers/api').Handler;
	const apiHandler = new ApiHandler(compileHandler);
	const SourceHandler = require('./lib/handlers/source').Handler;
	const sourceHandler = new SourceHandler(fileSources, staticHeaders);

	function ClientOptionsHandler(fileSources) {
	const sources = _.sortBy(fileSources.map(source => ({name: source.name, urlpart: source.urlpart})), "name");
	const languages = _.compact(_.map(gccProps("languages", '').split(':'), thing => {
	if (!thing) return null;
	var splat = thing.split("=");
	return {language: splat[0], url: splat[1]};
	}));
	const supportsBinary = !!compilerProps("supportsBinary", true);
	const supportsExecute = supportsBinary && !!compilerProps("supportsExecute", true);
	const libs = {};

	const baseLibs = compilerProps("libs");

	if (baseLibs) {
	_.each(baseLibs.split(':'), function (lib) {
	libs[lib] = {name: compilerProps('libs.' + lib + '.name')};
	libs[lib].versions = {};
	const listedVersions = compilerProps("libs." + lib + '.versions');
	if (listedVersions) {
	_.each(listedVersions.split(':'), function (version) {
	libs[lib].versions[version] = {};
	libs[lib].versions[version].version = compilerProps("libs." + lib + '.versions.' + version + '.version');
	libs[lib].versions[version].path = [];
	var listedIncludes = compilerProps("libs." + lib + '.versions.' + version + '.path');
	if (listedIncludes) {
	_.each(listedIncludes.split(':'), function (path) {
	libs[lib].versions[version].path.push(path);
	});
	} else {
	logger.warn("No paths found for " + lib + " version " + version);
	}
	});
	} else {
	logger.warn("No versions found for " + lib + " library");
	}
	});
	}
	const options = {
	googleAnalyticsAccount: gccProps('clientGoogleAnalyticsAccount', 'UA-55180-6'),
	googleAnalyticsEnabled: gccProps('clientGoogleAnalyticsEnabled', false),
	sharingEnabled: gccProps('clientSharingEnabled', true),
	githubEnabled: gccProps('clientGitHubRibbonEnabled', true),
	gapiKey: gccProps('googleApiKey', ''),
	googleShortLinkRewrite: gccProps('googleShortLinkRewrite', '').split('\|'),
	defaultSource: gccProps('defaultSource', ''),
	language: language,
	compilers: [],
	libs: libs,
	sourceExtension: compilerProps('compileFilename').split('.', 2)[1],
	defaultCompiler: compilerProps('defaultCompiler', ''),
	compileOptions: compilerProps('defaultOptions', ''),
	supportsBinary: supportsBinary,
	supportsExecute: supportsExecute,
	languages: languages,
	sources: sources,
	raven: gccProps('ravenUrl', ''),
	release: gitReleaseName,
	environment: env,
	localStoragePrefix: gccProps('localStoragePrefix'),
	cvCompilerCountMax: gccProps('cvCompilerCountMax', 6),
	defaultFontScale: gccProps('defaultFontScale', 1.0)
	};
	this.setCompilers = function (compilers) {
	options.compilers = compilers;
	};
	this.setCompilers([]);
	this.handler = function getClientOptions(req, res) {
	res.set('Content-Type', 'application/json');
	staticHeaders(res);
	res.end(JSON.stringify(options));
	};
	this.get = function () {
	return options;
	};
	}

	function retryPromise(promiseFunc, name, maxFails, retryMs) {
	return new Promise(function (resolve, reject) {
	var fails = 0;

	function doit() {
	var promise = promiseFunc();
	promise.then(function (arg) {
	resolve(arg);
	}, function (e) {
	fails++;
	if (fails < maxFails) {
	logger.warn("Failed " + name + " : " + e + ", retrying");
	setTimeout(doit, retryMs);
	} else {
	logger.error("Too many retries for " + name + " : " + e);
	reject(e);
	}
	});
	}

	doit();
	});
	}

	function findCompilers() {
	var exes = compilerProps("compilers", "/usr/bin/g++").split(":");
	var ndk = compilerProps('androidNdk');
	if (ndk) {
	var toolchains = fs.readdirSync(ndk + "/toolchains");
	toolchains.forEach(function (v, i, a) {
	var path = ndk + "/toolchains/" + v + "/prebuilt/linux-x86_64/bin/";
	if (fs.existsSync(path)) {
	var cc = fs.readdirSync(path).filter(function (filename) {
	return filename.indexOf("g++") !== -1;
	});
	a[i] = path + cc[0];
	} else {
	a[i] = null;
	}
	});
	toolchains = toolchains.filter(function (x) {
	return x !== null;
	});
	exes.push.apply(exes, toolchains);
	}

	function fetchRemote(host, port, props) {
	logger.info("Fetching compilers from remote source " + host + ":" + port);
	return retryPromise(function () {
	return new Promise(function (resolve, reject) {
	var request = http.get({
	hostname: host,
	port: port,
	path: "/api/compilers",
	headers: {
	'Accept': 'application/json'
	}
	}, function (res) {
	var str = '';
	res.on('data', function (chunk) {
	str += chunk;
	});
	res.on('end', function () {
	var compilers = JSON.parse(str).map(function (compiler) {
	compiler.exe = null;
	compiler.remote = "http://" + host + ":" + port;
	return compiler;
	});
	resolve(compilers);
	});
	}).on('error', function (e) {
	reject(e);
	}).on('timeout', function () {
	reject("timeout");
	});
	request.setTimeout(awsProps('proxyTimeout', 1000));
	});
	},
	host + ":" + port,
	props('proxyRetries', 5),
	props('proxyRetryMs', 500))
	.catch(function () {
	logger.warn("Unable to contact " + host + ":" + port + "; skipping");
	return [];
	});
	}

	function fetchAws() {
	logger.info("Fetching instances from AWS");
	return awsInstances().then(function (instances) {
	return Promise.all(instances.map(function (instance) {
	logger.info("Checking instance " + instance.InstanceId);
	var address = instance.PrivateDnsName;
	if (awsProps("externalTestMode", false)) {
	address = instance.PublicDnsName;
	}
	return fetchRemote(address, port, awsProps);
	}));
	});
	}

	function compilerConfigFor(name, parentProps) {
	const base = "compiler." + name,
	exe = compilerProps(base + ".exe", name);

	function props(name, def) {
	return parentProps(base + "." + name, parentProps(name, def));
	}

	var supportsBinary = !!props("supportsBinary", true);
	var supportsExecute = supportsBinary && !!props("supportsExecute", true);
	var compilerInfo = {
	id: name,
	exe: exe,
	name: props("name", name),
	alias: props("alias"),
	options: props("options"),
	versionFlag: props("versionFlag"),
	versionRe: props("versionRe"),
	compilerType: props("compilerType", ""),
	demangler: props("demangler", ""),
	objdumper: props("objdumper", ""),
	intelAsm: props("intelAsm", ""),
	needsMulti: !!props("needsMulti", true),
	supportsBinary: supportsBinary,
	supportsExecute: supportsExecute,
	postProcess: props("postProcess", "").split("\|")
	};
	logger.info("Found compiler", compilerInfo);
	return Promise.resolve(compilerInfo);
	}

	function recurseGetCompilers(name, parentProps) {
	if (fetchCompilersFromRemote && name.indexOf("@") !== -1) {
	var bits = name.split("@");
	var host = bits[0];
	var port = parseInt(bits[1]);
	return fetchRemote(host, port, gccProps);
	}
	if (name.indexOf("&") === 0) {
	var groupName = name.substr(1);

	var props = function (name, def) {
	if (name === "group") {
	return groupName;
	}
	return compilerProps("group." + groupName + "." + name, parentProps(name, def));
	};

	var exes = props('compilers', '').split(":");
	logger.info("Processing compilers from group " + groupName);
	return Promise.all(exes.map(function (compiler) {
	return recurseGetCompilers(compiler, props);
	}));
	}
	if (name === "AWS") return fetchAws();
	return compilerConfigFor(name, parentProps);
	}

	return Promise.all(exes.map(compiler => recurseGetCompilers(compiler, compilerProps)))
	.then(_.flatten)
	.then(compilers => compileHandler.setCompilers(compilers))
	.then(compilers => _.sortBy(_.compact(compilers), "name"));
	}

	function shortUrlHandler(req, res, next) {
	const resolver = new google.ShortLinkResolver(aws.getConfig('googleApiKey'));
	const bits = req.url.split("/");
	if (bits.length !== 2 \|\| req.method !== "GET") return next();
	const googleUrl = `http://goo.gl/${encodeURIComponent(bits[1])}`;
	resolver.resolve(googleUrl)
	.then(resultObj => {
	var parsed = url.parse(resultObj.longUrl);
	var allowedRe = new RegExp(gccProps('allowedShortUrlHostRe'));
	if (parsed.host.match(allowedRe) === null) {
	logger.warn("Denied access to short URL " + bits[1] + " - linked to " + resultObj.longUrl);
	return next();
	}
	res.writeHead(301, {
	Location: resultObj.id,
	'Cache-Control': 'public'
	});
	res.end();
	})
	.catch(e => {
	logger.error(`Failed to expand ${googleUrl} - ${e}`);
	next();
	});
	}

	Promise.all([findCompilers(), aws.initConfig(awsProps)])
	.then(function (args) {
	let compilers = args[0];
	var prevCompilers;

	const ravenPrivateEndpoint = aws.getConfig('ravenPrivateEndpoint');
	if (ravenPrivateEndpoint) {
	Raven.config(ravenPrivateEndpoint, {
	release: gitReleaseName,
	environment: env
	}).install();
	logger.info("Configured with raven endpoint", ravenPrivateEndpoint);
	} else {
	Raven.config(false).install();
	}

	const newRelicLicense = aws.getConfig('newRelicLicense');
	if (newRelicLicense) {
	process.env.NEW_RELIC_NO_CONFIG_FILE = true;
	process.env.NEW_RELIC_APP_NAME = 'Compiler Explorer';
	process.env.NEW_RELIC_LICENSE_KEY = newRelicLicense;
	process.env.NEW_RELIC_LABELS = 'Language:' + language;
	require('newrelic');
	logger.info('New relic configured with license', newRelicLicense);
	}

	function onCompilerChange(compilers) {
	if (JSON.stringify(prevCompilers) === JSON.stringify(compilers)) {
	return;
	}
	logger.info("Compilers:", compilers);
	if (compilers.length === 0) {
	logger.error("#### No compilers found: no compilation will be done!");
	}
	prevCompilers = compilers;
	clientOptionsHandler.setCompilers(compilers);
	apiHandler.setCompilers(compilers);
	}

	onCompilerChange(compilers);

	var rescanCompilerSecs = gccProps('rescanCompilerSecs', 0);
	if (rescanCompilerSecs) {
	logger.info("Rescanning compilers every " + rescanCompilerSecs + "secs");
	setInterval(function () {
	findCompilers().then(onCompilerChange);
	}, rescanCompilerSecs * 1000);
	}

	var webServer = express(),
	sFavicon = require('serve-favicon'),
	bodyParser = require('body-parser'),
	morgan = require('morgan'),
	compression = require('compression'),
	restreamer = require('./lib/restreamer');

	logger.info("=======================================");
	logger.info("Listening on http://" + (hostname \|\| 'localhost') + ":" + port + "/");
	logger.info(" serving static files from '" + staticDir + "'");
	if (gitReleaseName) logger.info(" git release " + gitReleaseName);

	function renderConfig(extra) {
	var options = _.extend(extra, clientOptionsHandler.get());
	options.compilerExplorerOptions = JSON.stringify(options);
	options.root = versionedRootPrefix;
	options.extraBodyClass = extraBodyClass;
	return options;
	}

	const embeddedHandler = function (req, res) {
	staticHeaders(res);
	res.render('embed', renderConfig({embedded: true}));
	};
	const healthCheck = require('./lib/handlers/health-check');
	webServer
	.use(Raven.requestHandler())
	.set('trust proxy', true)
	.set('view engine', 'pug')
	.use('/healthcheck', new healthCheck.HealthCheckHandler().handle) // before morgan so healthchecks aren't logged
	.use(morgan('combined', {stream: logger.stream}))
	.use(compression())
	.get('/', function (req, res) {
	staticHeaders(res);
	res.render('index', renderConfig({embedded: false}));
	})
	.get('/e', embeddedHandler)
	.get('/embed.html', embeddedHandler) // legacy. not a 301 to prevent any redirect loops between old e links and embed.html
	.get('/embed-ro', function (req, res) {
	staticHeaders(res);
	res.render('embed', renderConfig({embedded: true, readOnly: true}));
	})
	.get('/robots.txt', function (req, res) {
	staticHeaders(res);
	res.end('User-agent: *\nSitemap: https://godbolt.org/sitemap.xml');
	})
	.get('/sitemap.xml', function (req, res) {
	staticHeaders(res);
	res.set('Content-Type', 'application/xml');
	res.render('sitemap');
	})
	.use(sFavicon(staticDir + '/favicon.ico'))
	.use('/v', express.static(staticDir + '/v', {maxAge: Infinity, index: false}))
	.use(express.static(staticDir, {maxAge: staticMaxAgeSecs * 1000}));
	if (archivedVersions) {
	// The archived versions directory is used to serve "old" versioned data during updates. It's expected
	// to contain all the SHA-hashed directories from previous versions of Compiler Explorer.
	logger.info(" serving archived versions from", archivedVersions);
	webServer.use('/v', express.static(archivedVersions, {maxAge: Infinity, index: false}));
	}
	webServer
	.use(bodyParser.json({limit: gccProps('bodyParserLimit', '1mb')}))
	.use(bodyParser.text({
	limit: gccProps('bodyParserLimit', '1mb'), type: function () {
	return true;
	}
	}))
	.use(restreamer())
	.get('/client-options.json', clientOptionsHandler.handler)
	.use('/source', sourceHandler.handle.bind(sourceHandler))
	.use('/api', apiHandler.handle)
	.use('/g', shortUrlHandler);
	logger.info("=======================================");

	webServer.use(Raven.errorHandler());

	webServer.on('error', function (err) {
	logger.error('Caught error:', err, "(in web error handler; continuing)");
	});

	webServer.listen(port, hostname);
	})
	.catch(function (err) {
	logger.error("Promise error:", err, "(shutting down)");
	process.exit(1);
	});