In Node.js, how to import functions from another JavaScript file like source common.sh in Bash? In the .js file to be imported such as ‘common.js’, organize functions to be exported like module.exports = { func1: function () { // func1 impl }, func2: function () { // func2 impl } }; In the other .js…
How to get file extension from a file name in JavaScript? For examples, For “file.txt”, I want to get “txt”. For “file2.multi.ext.fileext”, I want to get “fileext”. This JavaScript function works well for me. function getExt(filename) { var idx = filename.lastIndexOf(‘.’); // handle cases like, .htaccess, filename return (idx < 1) ? “” : filename.substr(idx…
How to convert general JavaScript objects to json in Node.js? Assume jo is a JavaScript object, you can convert it to a json string by: JSON.stringify(jo)
Some JavaScript libraries send data by POST instead of JSON. In node.js, how to parse the POST data? You can use the “querystring” module: var qs = require(‘querystring’) The following piece of code works well for me. The comments should help you read the code well. var post_handle = function(request, response) { if (request.method ==…
When fatal error happened, we’d like to kill the program. How to exit the program in Node.js? You can use: process.exit() Here, “process” is a global process object. exit method ends the process. process.exit([code]) Ends the process with the specified code. If omitted, exit uses the ‘success’ code 0. To exit with a ‘failure’ code:…
How to install gitbook on my own Linux box? First, install node.js following https://www.systutorials.com/qa/1268/how-to-install-node-js-on-fedora or How to install node.js on Ubuntu/Linux Mint depending on your distro. Second, install gitbook by npm to /opt/: # cd /opt/ # npm install gitbook Then, the gitbook can be invoked by /opt/node_modules/gitbook/bin/gitbook.js You may need to install the latest…
How to install node.js on Ubuntu/Linux Mint? This is how I install node.js on Linux Mint: # aptitude install nodejs nodejs-legacy npm The nodejs-legacy makes sure the command node will invoke node.js.
How to install node.js on Fedora? You may install it by: # yum install nodejs npm