Saving Console Messages in JavaScript

Have you ever encountered a situation where it would be beneficial to save whatever is written to the console across browser sessions?  If you have, you know there are not many solutions.  I recently decided that localStorage would be a good candidate to implement a solution to this problem with.

logsaver.js

logsaver.js is a lightweight, simple log preservation script.  It utilizes the flexibility of JavaScript to replace the default console.log function with a new, customized one.  Along with writing messages to the original console.log, this custom console.log  also writes messages to the specified localStorage key.

  • To start saving console.log messages, call startSavingLog().
  • To stop saving console.log messages, call stopSavingLog().
  • To clear saved console.log messages, call clearSavedLog().
  • To completely remove the localStorage key used by logsaver, call removeSavedLog().

For more information on options and how to use them, checkout the readme.

While you can copy the source below, I strongly recommend grabbing the latest from github here: logsaver.js.

Notes:

  • It doesn’t handle objects well.  Results in [Object object] appearing in the localStorage key value.  This is because localStorage is limited to strings.
  • It is possible to exceed the maximum space allocated to you in localStorage.  For desktop browsers, Chrome and Firefox have a 10 MB limit, while Safari and IE both have a 5 MB limit.  These number differs for mobile browsers.  More details.  In this event, logsaver.js will stop trying to save the log and display additional error messages in the console.

v0.1.0 Source

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