docker.js

const { spawn } = require('child_process');

function run(cmd, image_name, filename, full_dirname, resolve) {
    const docker_process = spawn('sudo', [
        'docker', 'run', '--rm',
        '--memory', '75m',
        '--cpus', '0.5',
        '--name', filename,
        '--volume', full_dirname + ':/my',
        '--init',
        image_name,
        'timeout', '-s', 'SIGKILL', '5',
        '/bin/sh',
        '-c', cmd
    ], { detached: true });
    docker_process.stdout.setEncoding('utf-8'); docker_process.stderr.setEncoding('utf-8');

    setTimeout(() => {
        resolve({ "error": ">4 seconds: Time limit exceeded", "stdout": "", "stderr": "" });
    }, 4000);

    const resp = { "stdout": "", "stderr": "", "error": "" };
    docker_process.stderr.on('data', (data) => { resp.stderr += data });
    docker_process.stdout.on('data', (data) => {
        resp.stdout += data;
        if (resp.stdout.length > 5000) {
            resolve({ "error": ">5000 characters: Stdout limit exceeded", "stderr": resp.stderr, "stdout": resp.stdout });
        }
    });

    docker_process.on('exit', () => resolve(resp));
    docker_process.on('error', () => resolve({ "error": "Docker error", "stdout": "", "stderr": "" }));
}

function docker_run(filename, toRun, lang) {
    full_dirname = __dirname + '/temp/' + filename + '/';

    return new Promise((resolve) => {
        switch (lang) {
            case 'cpp':
                run('g++ "/my/' + toRun + '"; ./a.out < /my/in', 'run-cpp', filename, full_dirname, resolve);
                break;
            case 'py':
                run('python3 "/my/' + toRun + '" < /my/in', 'run-python', filename, full_dirname, resolve);
                break;
            case 'js':
                run('node "/my/' + toRun + '" < /my/in', 'run-js', filename, full_dirname, resolve);
                break;
            default:
                resolve({ "error": "supported languages are cpp, py, js", "stdout": "", "stderr": "" })
        }
    });
}

module.exports = docker_run;