@cake-hub/cake-screenshot_diffs/src/command-line.js

A CAKE Screenshot diffing tool that includes a setup to comapre two given resources by screenshots taken from the available pages.

const { exec } = require ("child_process");
const path = require ("path");

class CommandLine {

    static get COMMAND_TIMEOUT_MS () {
        return 1000 * 30; // timeout when no output available for more than 30 sec
    }

    static initializeTimeout (resolveMethod, timeout = null) {
        if (timeout) {
            clearTimeout (timeout);
        }
        return setTimeout (() => {
            console.log ("CommandLine", "Command timed out!");
            resolveMethod ();
        }, CommandLine.COMMAND_TIMEOUT_MS);
    }

    static execute (command, executionPath = path.resolve (__dirname, "../"), useTimeout = true) {
        return new Promise ((resolve, reject) => {
            const child = exec (command, {
                cwd: executionPath,
                stdio: ['pipe'],
                maxBuffer: 1024 * 1024 * 20,
            });

            let timeout = null;
            if (useTimeout) {
                timeout = CommandLine.initializeTimeout (resolve);
            }

            console.log ("CommandLine", "Started executing " + executionPath, command);
    
            child.stdout.on('data', (data) => {
                if (!data.toString ('utf8')) {
                    return;
                }
                console.log (executionPath, command, data.toString ('utf8'));
                if (useTimeout) {
                    timeout = CommandLine.initializeTimeout (resolve, timeout);
                }
            });
            
            child.on('exit', (code, signal) => {
                if (timeout) {
                    clearTimeout (timeout);
                }
                console.log ("EXIT", command, code, signal);
                return resolve (code);
            });

            child.on('error', (code) => {
                if (timeout) {
                    clearTimeout (timeout);
                }
                console.log ("ERROR", command, code);
                return reject (code);
            });
        });
    }

}

module.exports = CommandLine;