JSONovich

Pretty-prints JSON content in the Firefox family of browsers for easy, unobtrusive viewing.

JSONovich is a Firefox (and SeaMonkey) extension that pretty-prints JSON content of various types directly in a browser tab. It uses the browser's native JSON parser and a custom-built formatter to produce its output.

Normally, Firefox would prompt to download JSON sent with the correct application/json mime-type. JSONovich makes working with JSON and debugging output from web services easier by formatting JSON nicely inside the browser.

Features

• Syntax highlighting of JSON elements. [since 0.1]
• Indentation according to JSON object/array nesting level. [since 0.1]
• Line numbering based on JSON nodes and brackets, long strings always count as a single line. [since 0.8]
• Collapsible objects and arrays (whole line is clickable, not just a tiny +/- symbol). [since 1.5]
• Subtle zebra-stripes for easier reading. [since 1.7]
• Preserves formatting accurately when copying to clipboard, excluding line numbers. [since 0.9]
• Currently supports the following MIME types by default:

  application/json [since 0.1] (also legacy unofficial types application/x-json [since 1.8.2], text/json [since 1.8.2] and text/x-json [since 0.1])

  application/jsonrequest [since 1.6]

  application/sparql-results+json [since 0.9.1]

  application/schema+json [since 1.8.2]

  application/jsonml+json [since 1.8.2]

  application/rdf+json [since 1.4]

  application/javascript and variations [since 1.9.2]

  The above list is customisable by user preferences. [since 1.8.2]
• Supports loading JSON from files on disk with the following extensions by default:

  .json [since 1.8]

  .srj [since 1.8.2]

  The above list is customisable by user preferences. [since 1.8.2]
• Adds application/json to the default HTTP Accept header to make working with CouchDB easier. [since 1.1, optional since 1.8.2]
• Can override the default HTTP Accept header for individual hosts to either remove application/json or add it with a specific quality factor. [since 1.9]
• Options can be changed via the Add-ons Manager in Firefox 7+, Mobile 7+ and SeaMonkey 2.4+. [since 1.9]
• Options can be changed via about:config (extensions.jsonovich branch) in all browsers. [since 1.8]
• Restartless (even in older browsers, partially). [since 1.8]
• Full support for documents served with unusual character sets as well as the official UTF8. [fixed in 1.9]

Testing

• Want some sample JSON?
• Want to see how it handles invalid JSON?
• Or perhaps some Unicode?
• See how it handles JSON with HTML entities?

FAQ

• What's with the weird name?

  JSONovich is named after Pavement member Bob Nastanovich primarily because he seems like a swell guy.

• And the logo?

  That's called an Ambihelical Hexnut, an optical illusion similar to the impossible torus that is the JSON logo.

Bugs

To report a problem, please create an issue.

Working on the code

• Checkout the code.
• Create a clean browser profile for development.
• Place a proxy file in your profile/extensions directory called jsonovich@lackoftalent.org (no .txt extension). It should contain the path to the checked out src directory including a trailing slash.
  • There is also a jake build system for those with node.
• Hack at code.
• To see changes, either disable and re-enable the addon to save time, or restart the browser to be sure unload bugs don't affect the next test.
• Attach any patches to issues here and we can integrate them in the next release.

License

This extension is MPL 1.1/GPL 2.0/LGPL 2.1 tri-licensed.