lib/handlers/compile.ts - compiler-explorer - Rivoreo Source Code Repositories

 // Copyright (c) 2016, Compiler Explorer Authors
 // 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.

 import path from 'path';

 import * as Sentry from '@sentry/node';
 import express from 'express';
 import fs from 'fs-extra';
 import Server from 'http-proxy';
 import PromClient, {Counter} from 'prom-client';
 import temp from 'temp';
 import _ from 'underscore';
 import which from 'which';

 import {ICompiler} from '../../types/compiler.interfaces';
 import {BaseCompiler} from '../base-compiler';
 import {CompilationEnvironment} from '../compilation-env';
 import {getCompilerTypeByKey} from '../compilers';
 import {logger} from '../logger';
 import * as utils from '../utils';

 import {
     CompileRequestJsonBody,
     CompileRequestQueryArgs,
     CompileRequestTextBody,
     ExecutionRequestParams,
 } from './compile.interfaces';

 temp.track();

 let hasSetUpAutoClean = false;

 function initialise(compilerEnv: CompilationEnvironment) {
     if (hasSetUpAutoClean) return;
     hasSetUpAutoClean = true;
     const tempDirCleanupSecs = compilerEnv.ceProps('tempDirCleanupSecs', 600);
     logger.info(`Cleaning temp dirs every ${tempDirCleanupSecs} secs`);

     let cyclesBusy = 0;
     setInterval(() => {
         const status = compilerEnv.compilationQueue.status();
         if (status.busy) {
             cyclesBusy++;
             logger.warn(
                 `temp cleanup skipped, pending: ${status.pending}, waiting: ${status.size}, cycles: ${cyclesBusy}`,
             );
             return;
         }

         cyclesBusy = 0;

         temp.cleanup((err, stats) => {
             if (err) logger.error('temp cleanup error', err);
             if (stats) logger.debug('temp cleanup stats', stats);
         });
     }, tempDirCleanupSecs * 1000);
 }

 export type ExecutionParams = {
     args: string[];
     stdin: string;
 };

 type ParsedRequest = {
     source: string;
     options: string[];
     backendOptions: Record<string, any>;
     filters: Record<string, boolean>;
     bypassCache: boolean;
     tools: any;
     executionParameters: ExecutionParams;
     libraries: any[];
 };

 export class CompileHandler {
     private compilersById: Record<string, Record<string, BaseCompiler>> = {};
     private readonly compilerEnv: CompilationEnvironment;
     private readonly textBanner: string;
     private readonly proxy: Server;
     private readonly awsProps: (name: string, def?: string) => string;
     private clientOptions: Record<string, any> | null = null;
     private readonly compileCounter: Counter<string> = new PromClient.Counter({
         name: 'ce_compilations_total',
         help: 'Number of compilations',
         labelNames: ['language'],
     });
     private readonly executeCounter: Counter<string> = new PromClient.Counter({
         name: 'ce_executions_total',
         help: 'Number of executions',
         labelNames: ['language'],
     });
     private readonly cmakeCounter: Counter<string> = new PromClient.Counter({
         name: 'ce_cmake_compilations_total',
         help: 'Number of CMake compilations',
         labelNames: ['language'],
     });
     private readonly cmakeExecuteCounter: Counter<string> = new PromClient.Counter({
         name: 'ce_cmake_executions_total',
         help: 'Number of executions after CMake',
         labelNames: ['language'],
     });

     constructor(compilationEnvironment: CompilationEnvironment, awsProps: (name: string, def?: string) => string) {
         this.compilerEnv = compilationEnvironment;
         this.textBanner = this.compilerEnv.ceProps('textBanner');
         this.proxy = Server.createProxyServer({});
         this.awsProps = awsProps;
         initialise(this.compilerEnv);

         // Mostly cribbed from
         // https://github.com/nodejitsu/node-http-proxy/blob/master/examples/middleware/bodyDecoder-middleware.js
         // We just keep the body as-is though: no encoding using queryString.stringify(), as we don't use a form
         // decoding middleware.
         this.proxy.on('proxyReq', function (proxyReq, req) {
             // TODO ideally I'd work out if this is "ok" - IncomingMessage doesn't have a body, but pragmatically the
             //  object we get here does.
             const body = (req as any).body;
             if (!body || Object.keys(body).length === 0) {
                 return;
             }
             const contentType = proxyReq.getHeader('Content-Type');
             let bodyData;

             if (contentType === 'application/json') {
                 bodyData = JSON.stringify(body);
             }

             if (contentType === 'application/x-www-form-urlencoded') {
                 bodyData = body;
             }

             if (bodyData) {
                 proxyReq.setHeader('Content-Length', Buffer.byteLength(bodyData));
                 proxyReq.write(bodyData);
             }
         });
     }

     async create(compiler): Promise<ICompiler | null> {
         const isPrediscovered = !!compiler.version;

         const type = compiler.compilerType || 'default';
         let compilerClass;
         try {
             compilerClass = getCompilerTypeByKey(type);
         } catch (e) {
             logger.error(`Compiler ID: ${compiler.id}`);
             logger.error(e);
             process.exit(1);
         }

         // attempt to resolve non absolute exe paths
         if (compiler.exe && !path.isAbsolute(compiler.exe)) {
             const exe = await which(compiler.exe).catch(() => null);
             if (exe) {
                 logger.debug(`Resolved '${compiler.exe}' to path '${exe}'`);
                 compiler.exe = exe;
             } else {
                 // errors resolving to absolute path are not fatal for backwards compatibility sake
                 logger.error(`Unable to resolve '${compiler.exe}'`);
             }
         }

         if (compiler.exe && path.isAbsolute(compiler.exe)) {
             // Try stat'ing the compiler to cache its mtime and only re-run it if it
             // has changed since the last time.
             try {
                 let modificationTime;
                 if (!isPrediscovered) {
                     const res = await fs.stat(compiler.exe);
                     modificationTime = res.mtime;
                     const cached = this.findCompiler(compiler.lang, compiler.id);
                     if (cached && cached.getModificationTime() === res.mtime.getTime()) {
                         logger.debug(`${compiler.id} is unchanged`);
                         return cached;
                     }
                 } else {
                     modificationTime = compiler.mtime;
                 }
                 const compilerObj = new compilerClass(compiler, this.compilerEnv);
                 return compilerObj.initialise(modificationTime, this.clientOptions, isPrediscovered);
             } catch (err) {
                 logger.warn(`Unable to stat ${compiler.id} compiler binary: `, err);
                 return null;
             }
         } else {
             return new compilerClass(compiler, this.compilerEnv);
         }
     }

     async setCompilers(compilers: ICompiler[], clientOptions: Record<string, any>) {
         // Be careful not to update this.compilersById until we can replace it entirely.
         const compilersById = {};
         try {
             this.clientOptions = clientOptions;
             logger.info('Creating compilers: ' + compilers.length);
             let compilersCreated = 0;
             const createdCompilers = _.compact(await Promise.all(_.map(compilers, this.create, this)));
             for (const compiler of createdCompilers) {
                 const langId = compiler.getInfo().lang;
                 if (!compilersById[langId]) compilersById[langId] = {};
                 compilersById[langId][compiler.getInfo().id] = compiler;
                 compilersCreated++;
             }
             logger.info('Compilers created: ' + compilersCreated);
             if (this.awsProps) {
                 logger.info('Fetching possible arguments from storage');
                 await Promise.all(
                     createdCompilers.map(compiler => compiler.possibleArguments.loadFromStorage(this.awsProps)),
                 );
             }
             this.compilersById = compilersById;
             return createdCompilers.map(compiler => compiler.getInfo());
         } catch (err) {
             logger.error('Exception while processing compilers:', err);
         }
     }

     compilerAliasMatch(compiler, compilerId): boolean {
         return compiler.compiler.alias && compiler.compiler.alias.includes(compilerId);
     }

     compilerIdOrAliasMatch(compiler, compilerId): boolean {
         return compiler.compiler.id === compilerId || this.compilerAliasMatch(compiler, compilerId);
     }

     findCompiler(langId, compilerId): BaseCompiler | undefined {
         if (!compilerId) return;

         const langCompilers: Record<string, BaseCompiler> | undefined = this.compilersById[langId];
         if (langCompilers) {
             if (langCompilers[compilerId]) {
                 return langCompilers[compilerId];
             } else {
                 const compiler = _.find(langCompilers, compiler => {
                     return this.compilerAliasMatch(compiler, compilerId);
                 });

                 if (compiler) return compiler;
             }
         }

         // If the lang is bad, try to find it in every language
         let response: BaseCompiler | undefined;
         _.each(this.compilersById, compilerInLang => {
             if (!response) {
                 response = _.find(compilerInLang, compiler => {
                     return this.compilerIdOrAliasMatch(compiler, compilerId);
                 });
             }
         });

         return response;
     }

     compilerFor(req) {
         if (req.is('json')) {
             const lang = req.lang || req.body.lang;
             const compiler = this.findCompiler(lang, req.params.compiler);
             if (!compiler) {
                 const withoutBody = _.extend({}, req.body, {source: '<removed>'});
                 logger.warn(`Unable to find compiler with lang ${lang} for JSON request`, withoutBody);
             }
             return compiler;
         } else if (req.body && req.body.compiler) {
             const compiler = this.findCompiler(req.body.lang, req.body.compiler);
             if (!compiler) {
                 const withoutBody = _.extend({}, req.body, {source: '<removed>'});
                 logger.warn(`Unable to find compiler with lang ${req.body.lang} for request`, withoutBody);
             }
             return compiler;
         } else {
             const compiler = this.findCompiler(req.lang, req.params.compiler);
             if (!compiler) {
                 logger.warn(`Unable to find compiler with lang ${req.lang} for request params`, req.params);
             }
             return compiler;
         }
     }

     checkRequestRequirements(req: express.Request): CompileRequestJsonBody {
         if (req.body.options === undefined) throw new Error('Missing options property');
         if (req.body.source === undefined) throw new Error('Missing source property');
         return req.body;
     }

     parseRequest(req: express.Request, compiler: BaseCompiler): ParsedRequest {
         let source: string,
             options: string,
             backendOptions: Record<string, any> = {},
             filters: Record<string, boolean>,
             bypassCache = false,
             tools;
         const execReqParams: ExecutionRequestParams = {};
         let libraries: any[] = [];
         // IF YOU MODIFY ANYTHING HERE PLEASE UPDATE THE DOCUMENTATION!
         if (req.is('json')) {
             // JSON-style request
             const jsonRequest = this.checkRequestRequirements(req);
             const requestOptions = jsonRequest.options;
             source = jsonRequest.source;
             if (jsonRequest.bypassCache) bypassCache = true;
             options = requestOptions.userArguments;
             const execParams = requestOptions.executeParameters || {};
             execReqParams.args = execParams.args;
             execReqParams.stdin = execParams.stdin;
             backendOptions = requestOptions.compilerOptions || {};
             filters = {...compiler.getDefaultFilters(), ...requestOptions.filters};
             tools = requestOptions.tools;
             libraries = requestOptions.libraries || [];
         } else if (req.body && req.body.compiler) {
             const textRequest = req.body as CompileRequestTextBody;
             source = textRequest.source;
             if (textRequest.bypassCache) bypassCache = true;
             options = textRequest.userArguments;
             execReqParams.args = textRequest.executeParametersArgs;
             execReqParams.stdin = textRequest.executeParametersStdin;

             filters = compiler.getDefaultFilters();
             _.each(filters, (value, item) => {
                 filters[item] = textRequest[item] === 'true';
             });

             backendOptions.skipAsm = textRequest.skipAsm === 'true';
         } else {
             // API-style
             source = req.body;
             const query = req.query as CompileRequestQueryArgs;
             options = query.options || '';
             // By default we get the default filters.
             filters = compiler.getDefaultFilters();
             // If specified exactly, we'll take that with ?filters=a,b,c
             if (query.filters) {
                 filters = _.object(_.map(query.filters.split(','), filter => [filter, true])) as Record<
                     string,
                     boolean
                 >;
             }
             // Add a filter. ?addFilters=binary
             _.each((query.addFilters || '').split(','), filter => {
                 if (filter) filters[filter] = true;
             });
             // Remove a filter. ?removeFilter=intel
             _.each((query.removeFilters || '').split(','), filter => {
                 if (filter) delete filters[filter];
             });
             // Ask for asm not to be returned
             backendOptions.skipAsm = query.skipAsm === 'true';

             backendOptions.skipPopArgs = query.skipPopArgs === 'true';
         }
         const executionParameters: ExecutionParams = {
             args: !Array.isArray(execReqParams.args)
                 ? utils.splitArguments(execReqParams.args)
                 : execReqParams.args || '',
             stdin: execReqParams.stdin || '',
         };

         tools = tools || [];
         for (const tool of tools) {
             tool.args = utils.splitArguments(tool.args);
         }
         return {
             source,
             options: utils.splitArguments(options),
             backendOptions,
             filters,
             bypassCache,
             tools,
             executionParameters,
             libraries,
         };
     }

     handlePopularArguments(req: express.Request, res) {
         const compiler = this.compilerFor(req);
         if (!compiler) {
             return res.sendStatus(404);
         }
         res.send(compiler.possibleArguments.getPopularArguments(this.getUsedOptions(req)));
     }

     handleOptimizationArguments(req: express.Request, res) {
         const compiler = this.compilerFor(req);
         if (!compiler) {
             return res.sendStatus(404);
         }
         res.send(compiler.possibleArguments.getOptimizationArguments(this.getUsedOptions(req)));
     }

     getUsedOptions(req: express.Request) {
         if (req.body) {
             const data = typeof req.body === 'string' ? JSON.parse(req.body) : req.body;

             if (data.presplit) {
                 return data.usedOptions;
             } else {
                 return utils.splitArguments(data.usedOptions);
             }
         }
         return false;
     }

     handleApiError(error, res: express.Response, next: express.NextFunction) {
         if (error.message) {
             return res.status(400).send({
                 error: true,
                 message: error.message,
             });
         } else {
             return next(error);
         }
     }

     handleCmake(req: express.Request, res: express.Response, next: express.NextFunction) {
         const compiler = this.compilerFor(req);
         if (!compiler) {
             return res.sendStatus(404);
         }

         const remote = compiler.getRemote();
         if (remote) {
             req.url = remote.path;
             this.proxy.web(req, res, {target: remote.target, changeOrigin: true}, e => {
                 logger.error('Proxy error: ', e);
                 next(e);
             });
             return;
         }

         try {
             if (req.body.files === undefined) throw new Error('Missing files property');

             this.cmakeCounter.inc({language: compiler.lang.id});
             const options = this.parseRequest(req, compiler);
             compiler
                 .cmake(req.body.files, options)
                 .then(result => {
                     if (result.didExecute || (result.execResult && result.execResult.didExecute))
                         this.cmakeExecuteCounter.inc({language: compiler.lang.id});
                     res.send(result);
                 })
                 .catch(e => {
                     return this.handleApiError(e, res, next);
                 });
         } catch (e) {
             return this.handleApiError(e, res, next);
         }
     }

     handle(req: express.Request, res: express.Response, next: express.NextFunction) {
         const compiler = this.compilerFor(req);
         if (!compiler) {
             return res.sendStatus(404);
         }

         const remote = compiler.getRemote();
         if (remote) {
             req.url = remote.path;
             this.proxy.web(req, res, {target: remote.target, changeOrigin: true}, e => {
                 logger.error('Proxy error: ', e);
                 next(e);
             });
             return;
         }

         let parsedRequest: ParsedRequest | undefined;
         try {
             parsedRequest = this.parseRequest(req, compiler);
         } catch (error) {
             return this.handleApiError(error, res, next);
         }

         const {source, options, backendOptions, filters, bypassCache, tools, executionParameters, libraries} =
             parsedRequest;

         let files;
         if (req.body.files) files = req.body.files;

         if (source === undefined || Object.keys(req.body).length === 0) {
             logger.warn('No body found in request', req);
             return next(new Error('Bad request'));
         }

         function textify(array) {
             return _.pluck(array || [], 'text').join('\n');
         }

         this.compileCounter.inc({language: compiler.lang.id});
         // eslint-disable-next-line promise/catch-or-return
         compiler
             .compile(
                 source,
                 options,
                 backendOptions,
                 filters,
                 bypassCache,
                 tools,
                 executionParameters,
                 libraries,
                 files,
             )
             .then(
                 result => {
                     if (result.didExecute || (result.execResult && result.execResult.didExecute))
                         this.executeCounter.inc({language: compiler.lang.id});
                     if (req.accepts(['text', 'json']) === 'json') {
                         res.send(result);
                     } else {
                         res.set('Content-Type', 'text/plain');
                         try {
                             if (!_.isEmpty(this.textBanner)) res.write('# ' + this.textBanner + '\n');
                             res.write(textify(result.asm));
                             if (result.code !== 0) res.write('\n# Compiler exited with result code ' + result.code);
                             if (!_.isEmpty(result.stdout)) res.write('\nStandard out:\n' + textify(result.stdout));
                             if (!_.isEmpty(result.stderr)) res.write('\nStandard error:\n' + textify(result.stderr));

                             if (result.execResult) {
                                 res.write('\n\n# Execution result with exit code ' + result.execResult.code + '\n');
                                 if (!_.isEmpty(result.execResult.stdout)) {
                                     res.write('# Standard out:\n' + textify(result.execResult.stdout));
                                 }
                                 if (!_.isEmpty(result.execResult.stderr)) {
                                     res.write('\n# Standard error:\n' + textify(result.execResult.stderr));
                                 }
                             }
                         } catch (ex) {
                             Sentry.captureException(ex);
                             res.write(`Error handling request: ${ex}`);
                         }
                         res.end('\n');
                     }
                 },
                 error => {
                     if (typeof error !== 'string') {
                         if (error.stack) {
                             logger.error('Error during compilation: ', error);
                             Sentry.captureException(error);
                         } else if (error.code) {
                             logger.error('Error during compilation: ', error.code);
                             if (typeof error.stderr === 'string') {
                                 error.stdout = utils.parseOutput(error.stdout);
                                 error.stderr = utils.parseOutput(error.stderr);
                             }
                             res.end(JSON.stringify(error));
                             return;
                         } else {
                             logger.error('Error during compilation: ', error);
                         }

                         error = `Internal Compiler Explorer error: ${error.stack || error}`;
                     } else {
                         logger.error('Error during compilation: ', {error});
                     }
                     res.end(JSON.stringify({code: -1, stdout: [], stderr: [{text: error}]}));
                 },
             );
     }
 }

 export function SetTestMode() {
     hasSetUpAutoClean = true;
 }
	// Copyright (c) 2016, Compiler Explorer Authors
	// 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.

	import path from 'path';

	import * as Sentry from '@sentry/node';
	import express from 'express';
	import fs from 'fs-extra';
	import Server from 'http-proxy';
	import PromClient, {Counter} from 'prom-client';
	import temp from 'temp';
	import _ from 'underscore';
	import which from 'which';

	import {ICompiler} from '../../types/compiler.interfaces';
	import {BaseCompiler} from '../base-compiler';
	import {CompilationEnvironment} from '../compilation-env';
	import {getCompilerTypeByKey} from '../compilers';
	import {logger} from '../logger';
	import * as utils from '../utils';

	import {
	CompileRequestJsonBody,
	CompileRequestQueryArgs,
	CompileRequestTextBody,
	ExecutionRequestParams,
	} from './compile.interfaces';

	temp.track();

	let hasSetUpAutoClean = false;

	function initialise(compilerEnv: CompilationEnvironment) {
	if (hasSetUpAutoClean) return;
	hasSetUpAutoClean = true;
	const tempDirCleanupSecs = compilerEnv.ceProps('tempDirCleanupSecs', 600);
	logger.info(`Cleaning temp dirs every ${tempDirCleanupSecs} secs`);

	let cyclesBusy = 0;
	setInterval(() => {
	const status = compilerEnv.compilationQueue.status();
	if (status.busy) {
	cyclesBusy++;
	logger.warn(
	`temp cleanup skipped, pending: ${status.pending}, waiting: ${status.size}, cycles: ${cyclesBusy}`,
	);
	return;
	}

	cyclesBusy = 0;

	temp.cleanup((err, stats) => {
	if (err) logger.error('temp cleanup error', err);
	if (stats) logger.debug('temp cleanup stats', stats);
	});
	}, tempDirCleanupSecs * 1000);
	}

	export type ExecutionParams = {
	args: string[];
	stdin: string;
	};

	type ParsedRequest = {
	source: string;
	options: string[];
	backendOptions: Record<string, any>;
	filters: Record<string, boolean>;
	bypassCache: boolean;
	tools: any;
	executionParameters: ExecutionParams;
	libraries: any[];
	};

	export class CompileHandler {
	private compilersById: Record<string, Record<string, BaseCompiler>> = {};
	private readonly compilerEnv: CompilationEnvironment;
	private readonly textBanner: string;
	private readonly proxy: Server;
	private readonly awsProps: (name: string, def?: string) => string;
	private clientOptions: Record<string, any> \| null = null;
	private readonly compileCounter: Counter<string> = new PromClient.Counter({
	name: 'ce_compilations_total',
	help: 'Number of compilations',
	labelNames: ['language'],
	});
	private readonly executeCounter: Counter<string> = new PromClient.Counter({
	name: 'ce_executions_total',
	help: 'Number of executions',
	labelNames: ['language'],
	});
	private readonly cmakeCounter: Counter<string> = new PromClient.Counter({
	name: 'ce_cmake_compilations_total',
	help: 'Number of CMake compilations',
	labelNames: ['language'],
	});
	private readonly cmakeExecuteCounter: Counter<string> = new PromClient.Counter({
	name: 'ce_cmake_executions_total',
	help: 'Number of executions after CMake',
	labelNames: ['language'],
	});

	constructor(compilationEnvironment: CompilationEnvironment, awsProps: (name: string, def?: string) => string) {
	this.compilerEnv = compilationEnvironment;
	this.textBanner = this.compilerEnv.ceProps('textBanner');
	this.proxy = Server.createProxyServer({});
	this.awsProps = awsProps;
	initialise(this.compilerEnv);

	// Mostly cribbed from
	// https://github.com/nodejitsu/node-http-proxy/blob/master/examples/middleware/bodyDecoder-middleware.js
	// We just keep the body as-is though: no encoding using queryString.stringify(), as we don't use a form
	// decoding middleware.
	this.proxy.on('proxyReq', function (proxyReq, req) {
	// TODO ideally I'd work out if this is "ok" - IncomingMessage doesn't have a body, but pragmatically the
	// object we get here does.
	const body = (req as any).body;
	if (!body \|\| Object.keys(body).length === 0) {
	return;
	}
	const contentType = proxyReq.getHeader('Content-Type');
	let bodyData;

	if (contentType === 'application/json') {
	bodyData = JSON.stringify(body);
	}

	if (contentType === 'application/x-www-form-urlencoded') {
	bodyData = body;
	}

	if (bodyData) {
	proxyReq.setHeader('Content-Length', Buffer.byteLength(bodyData));
	proxyReq.write(bodyData);
	}
	});
	}

	async create(compiler): Promise<ICompiler \| null> {
	const isPrediscovered = !!compiler.version;

	const type = compiler.compilerType \|\| 'default';
	let compilerClass;
	try {
	compilerClass = getCompilerTypeByKey(type);
	} catch (e) {
	logger.error(`Compiler ID: ${compiler.id}`);
	logger.error(e);
	process.exit(1);
	}

	// attempt to resolve non absolute exe paths
	if (compiler.exe && !path.isAbsolute(compiler.exe)) {
	const exe = await which(compiler.exe).catch(() => null);
	if (exe) {
	logger.debug(`Resolved '${compiler.exe}' to path '${exe}'`);
	compiler.exe = exe;
	} else {
	// errors resolving to absolute path are not fatal for backwards compatibility sake
	logger.error(`Unable to resolve '${compiler.exe}'`);
	}
	}

	if (compiler.exe && path.isAbsolute(compiler.exe)) {
	// Try stat'ing the compiler to cache its mtime and only re-run it if it
	// has changed since the last time.
	try {
	let modificationTime;
	if (!isPrediscovered) {
	const res = await fs.stat(compiler.exe);
	modificationTime = res.mtime;
	const cached = this.findCompiler(compiler.lang, compiler.id);
	if (cached && cached.getModificationTime() === res.mtime.getTime()) {
	logger.debug(`${compiler.id} is unchanged`);
	return cached;
	}
	} else {
	modificationTime = compiler.mtime;
	}
	const compilerObj = new compilerClass(compiler, this.compilerEnv);
	return compilerObj.initialise(modificationTime, this.clientOptions, isPrediscovered);
	} catch (err) {
	logger.warn(`Unable to stat ${compiler.id} compiler binary: `, err);
	return null;
	}
	} else {
	return new compilerClass(compiler, this.compilerEnv);
	}
	}

	async setCompilers(compilers: ICompiler[], clientOptions: Record<string, any>) {
	// Be careful not to update this.compilersById until we can replace it entirely.
	const compilersById = {};
	try {
	this.clientOptions = clientOptions;
	logger.info('Creating compilers: ' + compilers.length);
	let compilersCreated = 0;
	const createdCompilers = _.compact(await Promise.all(_.map(compilers, this.create, this)));
	for (const compiler of createdCompilers) {
	const langId = compiler.getInfo().lang;
	if (!compilersById[langId]) compilersById[langId] = {};
	compilersById[langId][compiler.getInfo().id] = compiler;
	compilersCreated++;
	}
	logger.info('Compilers created: ' + compilersCreated);
	if (this.awsProps) {
	logger.info('Fetching possible arguments from storage');
	await Promise.all(
	createdCompilers.map(compiler => compiler.possibleArguments.loadFromStorage(this.awsProps)),
	);
	}
	this.compilersById = compilersById;
	return createdCompilers.map(compiler => compiler.getInfo());
	} catch (err) {
	logger.error('Exception while processing compilers:', err);
	}
	}

	compilerAliasMatch(compiler, compilerId): boolean {
	return compiler.compiler.alias && compiler.compiler.alias.includes(compilerId);
	}

	compilerIdOrAliasMatch(compiler, compilerId): boolean {
	return compiler.compiler.id === compilerId \|\| this.compilerAliasMatch(compiler, compilerId);
	}

	findCompiler(langId, compilerId): BaseCompiler \| undefined {
	if (!compilerId) return;

	const langCompilers: Record<string, BaseCompiler> \| undefined = this.compilersById[langId];
	if (langCompilers) {
	if (langCompilers[compilerId]) {
	return langCompilers[compilerId];
	} else {
	const compiler = _.find(langCompilers, compiler => {
	return this.compilerAliasMatch(compiler, compilerId);
	});

	if (compiler) return compiler;
	}
	}

	// If the lang is bad, try to find it in every language
	let response: BaseCompiler \| undefined;
	_.each(this.compilersById, compilerInLang => {
	if (!response) {
	response = _.find(compilerInLang, compiler => {
	return this.compilerIdOrAliasMatch(compiler, compilerId);
	});
	}
	});

	return response;
	}

	compilerFor(req) {
	if (req.is('json')) {
	const lang = req.lang \|\| req.body.lang;
	const compiler = this.findCompiler(lang, req.params.compiler);
	if (!compiler) {
	const withoutBody = _.extend({}, req.body, {source: '<removed>'});
	logger.warn(`Unable to find compiler with lang ${lang} for JSON request`, withoutBody);
	}
	return compiler;
	} else if (req.body && req.body.compiler) {
	const compiler = this.findCompiler(req.body.lang, req.body.compiler);
	if (!compiler) {
	const withoutBody = _.extend({}, req.body, {source: '<removed>'});
	logger.warn(`Unable to find compiler with lang ${req.body.lang} for request`, withoutBody);
	}
	return compiler;
	} else {
	const compiler = this.findCompiler(req.lang, req.params.compiler);
	if (!compiler) {
	logger.warn(`Unable to find compiler with lang ${req.lang} for request params`, req.params);
	}
	return compiler;
	}
	}

	checkRequestRequirements(req: express.Request): CompileRequestJsonBody {
	if (req.body.options === undefined) throw new Error('Missing options property');
	if (req.body.source === undefined) throw new Error('Missing source property');
	return req.body;
	}

	parseRequest(req: express.Request, compiler: BaseCompiler): ParsedRequest {
	let source: string,
	options: string,
	backendOptions: Record<string, any> = {},
	filters: Record<string, boolean>,
	bypassCache = false,
	tools;
	const execReqParams: ExecutionRequestParams = {};
	let libraries: any[] = [];
	// IF YOU MODIFY ANYTHING HERE PLEASE UPDATE THE DOCUMENTATION!
	if (req.is('json')) {
	// JSON-style request
	const jsonRequest = this.checkRequestRequirements(req);
	const requestOptions = jsonRequest.options;
	source = jsonRequest.source;
	if (jsonRequest.bypassCache) bypassCache = true;
	options = requestOptions.userArguments;
	const execParams = requestOptions.executeParameters \|\| {};
	execReqParams.args = execParams.args;
	execReqParams.stdin = execParams.stdin;
	backendOptions = requestOptions.compilerOptions \|\| {};
	filters = {...compiler.getDefaultFilters(), ...requestOptions.filters};
	tools = requestOptions.tools;
	libraries = requestOptions.libraries \|\| [];
	} else if (req.body && req.body.compiler) {
	const textRequest = req.body as CompileRequestTextBody;
	source = textRequest.source;
	if (textRequest.bypassCache) bypassCache = true;
	options = textRequest.userArguments;
	execReqParams.args = textRequest.executeParametersArgs;
	execReqParams.stdin = textRequest.executeParametersStdin;

	filters = compiler.getDefaultFilters();
	_.each(filters, (value, item) => {
	filters[item] = textRequest[item] === 'true';
	});

	backendOptions.skipAsm = textRequest.skipAsm === 'true';
	} else {
	// API-style
	source = req.body;
	const query = req.query as CompileRequestQueryArgs;
	options = query.options \|\| '';
	// By default we get the default filters.
	filters = compiler.getDefaultFilters();
	// If specified exactly, we'll take that with ?filters=a,b,c
	if (query.filters) {
	filters = _.object(_.map(query.filters.split(','), filter => [filter, true])) as Record<
	string,
	boolean
	>;
	}
	// Add a filter. ?addFilters=binary
	_.each((query.addFilters \|\| '').split(','), filter => {
	if (filter) filters[filter] = true;
	});
	// Remove a filter. ?removeFilter=intel
	_.each((query.removeFilters \|\| '').split(','), filter => {
	if (filter) delete filters[filter];
	});
	// Ask for asm not to be returned
	backendOptions.skipAsm = query.skipAsm === 'true';

	backendOptions.skipPopArgs = query.skipPopArgs === 'true';
	}
	const executionParameters: ExecutionParams = {
	args: !Array.isArray(execReqParams.args)
	? utils.splitArguments(execReqParams.args)
	: execReqParams.args \|\| '',
	stdin: execReqParams.stdin \|\| '',
	};

	tools = tools \|\| [];
	for (const tool of tools) {
	tool.args = utils.splitArguments(tool.args);
	}
	return {
	source,
	options: utils.splitArguments(options),
	backendOptions,
	filters,
	bypassCache,
	tools,
	executionParameters,
	libraries,
	};
	}

	handlePopularArguments(req: express.Request, res) {
	const compiler = this.compilerFor(req);
	if (!compiler) {
	return res.sendStatus(404);
	}
	res.send(compiler.possibleArguments.getPopularArguments(this.getUsedOptions(req)));
	}

	handleOptimizationArguments(req: express.Request, res) {
	const compiler = this.compilerFor(req);
	if (!compiler) {
	return res.sendStatus(404);
	}
	res.send(compiler.possibleArguments.getOptimizationArguments(this.getUsedOptions(req)));
	}

	getUsedOptions(req: express.Request) {
	if (req.body) {
	const data = typeof req.body === 'string' ? JSON.parse(req.body) : req.body;

	if (data.presplit) {
	return data.usedOptions;
	} else {
	return utils.splitArguments(data.usedOptions);
	}
	}
	return false;
	}

	handleApiError(error, res: express.Response, next: express.NextFunction) {
	if (error.message) {
	return res.status(400).send({
	error: true,
	message: error.message,
	});
	} else {
	return next(error);
	}
	}

	handleCmake(req: express.Request, res: express.Response, next: express.NextFunction) {
	const compiler = this.compilerFor(req);
	if (!compiler) {
	return res.sendStatus(404);
	}

	const remote = compiler.getRemote();
	if (remote) {
	req.url = remote.path;
	this.proxy.web(req, res, {target: remote.target, changeOrigin: true}, e => {
	logger.error('Proxy error: ', e);
	next(e);
	});
	return;
	}

	try {
	if (req.body.files === undefined) throw new Error('Missing files property');

	this.cmakeCounter.inc({language: compiler.lang.id});
	const options = this.parseRequest(req, compiler);
	compiler
	.cmake(req.body.files, options)
	.then(result => {
	if (result.didExecute \|\| (result.execResult && result.execResult.didExecute))
	this.cmakeExecuteCounter.inc({language: compiler.lang.id});
	res.send(result);
	})
	.catch(e => {
	return this.handleApiError(e, res, next);
	});
	} catch (e) {
	return this.handleApiError(e, res, next);
	}
	}

	handle(req: express.Request, res: express.Response, next: express.NextFunction) {
	const compiler = this.compilerFor(req);
	if (!compiler) {
	return res.sendStatus(404);
	}

	const remote = compiler.getRemote();
	if (remote) {
	req.url = remote.path;
	this.proxy.web(req, res, {target: remote.target, changeOrigin: true}, e => {
	logger.error('Proxy error: ', e);
	next(e);
	});
	return;
	}

	let parsedRequest: ParsedRequest \| undefined;
	try {
	parsedRequest = this.parseRequest(req, compiler);
	} catch (error) {
	return this.handleApiError(error, res, next);
	}

	const {source, options, backendOptions, filters, bypassCache, tools, executionParameters, libraries} =
	parsedRequest;

	let files;
	if (req.body.files) files = req.body.files;

	if (source === undefined \|\| Object.keys(req.body).length === 0) {
	logger.warn('No body found in request', req);
	return next(new Error('Bad request'));
	}

	function textify(array) {
	return _.pluck(array \|\| [], 'text').join('\n');
	}

	this.compileCounter.inc({language: compiler.lang.id});
	// eslint-disable-next-line promise/catch-or-return
	compiler
	.compile(
	source,
	options,
	backendOptions,
	filters,
	bypassCache,
	tools,
	executionParameters,
	libraries,
	files,
	)
	.then(
	result => {
	if (result.didExecute \|\| (result.execResult && result.execResult.didExecute))
	this.executeCounter.inc({language: compiler.lang.id});
	if (req.accepts(['text', 'json']) === 'json') {
	res.send(result);
	} else {
	res.set('Content-Type', 'text/plain');
	try {
	if (!_.isEmpty(this.textBanner)) res.write('# ' + this.textBanner + '\n');
	res.write(textify(result.asm));
	if (result.code !== 0) res.write('\n# Compiler exited with result code ' + result.code);
	if (!_.isEmpty(result.stdout)) res.write('\nStandard out:\n' + textify(result.stdout));
	if (!_.isEmpty(result.stderr)) res.write('\nStandard error:\n' + textify(result.stderr));

	if (result.execResult) {
	res.write('\n\n# Execution result with exit code ' + result.execResult.code + '\n');
	if (!_.isEmpty(result.execResult.stdout)) {
	res.write('# Standard out:\n' + textify(result.execResult.stdout));
	}
	if (!_.isEmpty(result.execResult.stderr)) {
	res.write('\n# Standard error:\n' + textify(result.execResult.stderr));
	}
	}
	} catch (ex) {
	Sentry.captureException(ex);
	res.write(`Error handling request: ${ex}`);
	}
	res.end('\n');
	}
	},
	error => {
	if (typeof error !== 'string') {
	if (error.stack) {
	logger.error('Error during compilation: ', error);
	Sentry.captureException(error);
	} else if (error.code) {
	logger.error('Error during compilation: ', error.code);
	if (typeof error.stderr === 'string') {
	error.stdout = utils.parseOutput(error.stdout);
	error.stderr = utils.parseOutput(error.stderr);
	}
	res.end(JSON.stringify(error));
	return;
	} else {
	logger.error('Error during compilation: ', error);
	}

	error = `Internal Compiler Explorer error: ${error.stack \|\| error}`;
	} else {
	logger.error('Error during compilation: ', {error});
	}
	res.end(JSON.stringify({code: -1, stdout: [], stderr: [{text: error}]}));
	},
	);
	}
	}

	export function SetTestMode() {
	hasSetUpAutoClean = true;
	}