remark-mermaid

Replaces fenced code blocks in mermaid format with:

• Links to rendered SVG files of the graph (default mode).
• Mermaid-formatted code wrapped in div tags for rendering by mermaidjs (simple mode).

You might also like remark-graphviz.

Installation

$ npm install remark-mermaid mermaid.cli

Usage

Graphs defined using mermaid can be referenced using a mermaid: title which will generate an SVG image.

[Link to a Graph](test/fixtures/assets/example.mmd "mermaid:")
![Embed image of graph](test/fixtures/assets/example.mdd "mermaid:")

Alternatively, graphs can be generated inline, by using mermaid as the language identifier for a fenced code block.

See this project's fixtures for more examples.

Options

• simple: when set to true, plugin will wrap mermaid graphs in an <div class="mermaid"> element instead of generating an SVG. Defaults to false.

Example

SVG Generation

Given a file, example.md, which contains the following Markdown:

Using remark like follows:

var vfile = require('to-vfile');
var remark = require('remark');
var mermaid = require('remark-mermaid');

var example = vfile.readSync('example.md');

remark()
  .use(mermaid)
  .process(example, function (err, file) {
    if (err) throw err;
    console.log(String(file));
  });

Will result in an SVG being written relative to example.md, and the Markdown being transformed to:

# mermaid code block

![](./6b03e143dc2a47a93496133d692c44d5ec012b57.svg "`mermaid` image")

To change where the SVG's are written, set data.destinationDir on the vFile:

var vfile = require('to-vfile');
var remark = require('remark');
var mermaid = require('remark-mermaid');

var example = vfile.readSync('example.md');
example.data = {
  destinationDir: '~/absolute/path/to/output'
};

remark()
  .use(mermaid)
  .process(example, function (err, file) {
    if (err) throw err;
    vfile.writeSync({ path: example.destinationFilePath });
  });

This allows you process files from one directory, and save the results to another.

Simple mode

The following code sample enables simple mode:

var vfile = require('to-vfile');
var remark = require('remark');
var mermaid = require('remark-mermaid');

var example = vfile.readSync('example.md');

remark()
  .use(mermaid, { simple: true })
  .process(example, function (err, file) {
    if (err) throw err;
    console.log(String(file));
  });

This will result in the following Markdown output:

# mermaid code block

<div class="mermaid">
  graph LR
    Start --> Stop
</div>

mermaidjs