Vim-Markdown-Extra-Preview

Preview Markdown documents in a Browser.

This plugin passes the current buffer through Python-Markdown (with the extra extension) and displays the resulting HTML in the system default browser.

The Python-Markdown library is included. However, Vim must be compiled with Python support (+python) and the matching version of Python must be installed on the system. The plugin checks this when called and will fail with an error message if Python is not available.

Usage

There are two commands available:

Run the command :Me to preview the current buffer. This is the normal mode, converts the markdown buffer to a html file and open it in a new browser window or tab with the result.
Run the command :Mer to refresh the current buffer. The intention of this mode is making it work together with a browser plugin that reload the page when it changes. Then, this mode don't open a new browser tab or window, only save the html file to the disk. With a plugin like the Firefox's Auto Reload the browser tab it's automatically reloaded in order to view the changes.

Options

Global Settings:

The following settings can be set globally in your .vimrc file and will effect the behavior of the plugin in all instances. Changing the global settings in one buffer will effect all buffers. See Local Settings if you want to change setting for a specific buffer.

g:VMEPoutputformat

The format of Markdown's output. This setting is simply passed on to Python-Markdown as-is and determines which format is output.

The formats are:
- 'xhtml' (default)
- 'html'
g:VMEPextensions

A list of extensions to be used by Python-Markdown when parsing the buffer. See Python-Markdown's documentation for a description of each extension. The 'extra' extension is used by default.
g:VMEPtemplate

The template in which the Markdown output is inserted. A default template is provided with the plugin. Additional templates may be added to the templates directory, and if set to that template's name (i.e., mytemplate.html), that template us used. If set to a full path of an existing file anywhere on the system (i.e., /path/to/mytemplate.html), then that file is used.
g:VMEPstylesheet

The style sheet which is linked to in the HTML output. If a filename is given, then the style sheet is assumed to be in the plugin's stylesheets directory. If a full path is given, then that path is used as-is.
g:VMEPoutputdirectory

The directory in which the output will be written before being displayed in the browser. This must be a full path which is writable. When assigned an empty value(``), it is assumed that the system default temporary directory should be used. Empty by default.
g:VMEPhtmlreader

The browser in which the output will be displayed. Defaults to the system's default browser. May be set to any executable of your choosing that is on the system path, or with a full path. The executable must except the path to the HTML output file as it's only argument.

Local Settings

Local settings are the same as the global settings except that they only apply to a single buffer. If a local setting is not set, the corresponding global setting will be used. To set a local setting, prepend the setting name with b: rather than g: (i.e., use b:VMEPstylesheet rather than g:VEMPstylesheet).

For example, to use a different template, when viewing the buffer, execute the following command:

:let b:VMEPtemplate = '/path/to/template.html'

You could also use autocommands in your .vimrc file to use a different setting for all files in a specific directory or of a specific type. Something like:

au BufNewFile,BufRead /path/to/project/* \
                let b:VMEPtemplate = '/path/to/template.html' | \
                let b:VMEPstylesheet = '/path/to/style.css'

Note that each command is separated by a |. The \ indicate line wraps as the command should all be one line.

You could even create a .vimrc file in your project directory and source it:

au BufNewFile,BufRead /path/to/project/* source /path/to/project/.vimrc

Just make sure your local .vimrc only defines buffer specific settings.

Templates

The template pointed to by the g:VMEPtemplate setting must be a file which is readable and contains the wrapper around which Markdown's output is inserted. The file extension of the template is used as the file extension of the output file. Templates use Python's string formatting to insert the following data:

name:

The name of the buffer with the file-extension removed and underscores replaced by spaces (i.e., foo_bar.txt becomes foo bar). This is generally expected to be used in the documents title.
content:

The full body of Markdown's output.
style:

The full path to the style sheet set in g:VMEPstylesheet.

If Python-Markdown's Meta-Data extension is used, any meta-data defined in the buffer will also be added to the context passed to the template. The meta-data will overwrite any of the existing data. This could be useful for setting a more verbose 'name' for the document or to set a document specific style. But it could also overwrite data if not used with care.

To enable the meta-data extension, it will need to included in the g:VMEPextensions setting (or its buffer specific counterpart) like this:

:let g:VMEPextensions = ['extra', 'meta']

A simple template may look something like this:

 <html>
   <head>
     <title>%(name)s</title>
      <link rel="stylesheet" href="%(style)s"></link>
    </head>
    <body>
      %(content)s
    </body>
 </html>