I could not find a tool that would allow me to preview Github Flavored Markdown files offline, so I wrote one. (Well it's not completely offline - it loads the Github CSS from Akamai and JQuery from Google's CDN, but you know how to cache them if you need to.)
Basically the only way how to preview GFM somewhat properly, was to commit the file to the Github repo and reload the browser page. However committing just for preview unecessarily pollutes GIT history of the file, and it's a tedious process.
Sure, there are various good Markdown editors for all platforms, but only a few support GFM, and to my knowledge, none properly supports the syntax-colored code blocks denoted by three apostrophes, e.g.
function(arg) {
// some code here
for(var i = 0; i < 10; i++)
console.log('hello ' + i);
}And none would show the result looking (almost) exactly like at Github.
Well, the current implementation of GFMS doesn't color the source code blocks, but it at least renders them correctly. I had to modify the showdown.js from github-flavored-markdown. I made a copy of that file, and fork & pull-request to the original project is on my TODO list. GFMS has github-flavored-markdown as a dependency despite it's not needed, so that the heritage is obvious in NPM.
Another possible shortcoming is that the URLs of the Github CSS files are scraped from www.github.com directly, introducing some fragility inherent to the nature of scraping.
[sudo] npm install gfms -g
cd your-github-project-dir
gfms -p 1234
(If you don't know how to install NPM, see here: http://npmjs.org/)
Now browse to http://localhost:1234, and select the .md or .markdown file to view.
When you save the source Markdown file in your editor, it will be automatically updated in your browser. So perhaps a good setup is to have both your editor window and your browser window visible at the same time, so that you don't have to switch in between.
(The MIT License)
Copyright (c) 2012 Juraj Vitko (http://ypocat.com)
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