How to remove console log from your JavaScript files programmatically?

March 21, 2019  1 minute read  

Learn how to remove JavaScript console methods such as console log programmatically from your JavaScript files.


1. sed

sed is defined as following on GNU site.

sed is a stream editor. A stream editor is used to perform basic text transformations on an input stream (a file or input from a pipeline).

sed command

You can run the following command to remove console methods from your input JavaScript file: in.js and the output JavaScript file would be out.js.

sed -E 's/console.(log|debug)\((.*)\);?//g' <in.js >out.js

Description of -E flag from man sed

Interpret regular expressions as extended (modern) regular expressions rather than basic regular expressions (BRE’s). The re_format(7) manual page fully describes both formats.

You can edit this list: log|debug to remove the console method you want to remove. For example,if you want to remove console log, debug, info and count, change that list to log|debug|info|count.

You can use this regex test website to check if it works.

2. gulp-strip-debug package

If your have a lot of files to clean up. You should use gulp and gulp-strip-debug package to efficiently remove console methods.

i. Install gulp if you haven’t.

npm install --save-dev gulp

Gulp is a build system that automates development tasks. Read more about Gulp on Google developers document.

ii. Install gulp-strip-debug package

npm install --save-dev gulp-strip-debug

iii. Create a gulpfile

Configure gulp using a file called gulpfile.js to set the input and output file path using JavaScript below.

const gulp = require('gulp');
const stripDebug = require('gulp-strip-debug');

gulp.task('strip-debug', () =>
  gulp.src('./**.js') // input file path
    .pipe(stripDebug()) // execute gulp-strip-debug
    .pipe(gulp.dest('./')) // output file path 

iv. Add Command to your package.json

In your scripts object inside your package.json, you can add a new command, let’s say, command alias is cleanup which will execute gulp strip-debug.

"scripts": {
  "cleanup": "gulp strip-debug"

v. Execute npm run cleanup

Now, run npm run cleanup command. and it will remove console, alert and debugger from your JavaScript files.

gulp-strip-debug execution

With this, you can remove console methods from your JavaScript files programmatically.

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