Sequence and Graph diagrams in your markdown files!
mermaid-filter is a pandoc filter that adds support for mermaid syntax diagrams in markdown.
Write your diagrams in fenced code blocks as usual like this:
~~~mermaid
sequenceDiagram
Alice->>John: Hello John, how are you?
John-->>Alice: Great!
~~~
and get this in rendered doc
Installation and usage
npm install --global mermaid-filter- To convert your markdown file
something.mdintosomething.html, usepandoc -t html -F mermaid-filter -o something.html something.md
WINDOWS - you need mermaid-filter.cmd in the line above
Windows 8.1 - On windows 8.1, mermaid-filter.cmd fails - apparently due to change in how the CMD.exe works
for subprocesses? - see this issue thread.
You have to edit the globally installed mermaid-filter.cmd located in c:\users\<username>\AppData\Roaming\npm
to use ~dp$PATH:0.
Unfortunately, you will need to do this each time you install/update mermaid-filter since it overwrites the cmd file.
Options
You have a couple of formatting options via attributes of the fenced code block to control the rendering
- Pandoc caption, the filename is this value cleaned up - Use
{.mermaid caption="Caption Text Here"} - Image Format - Use
{.mermaid format=svg}Default is png - Width - Use
{.mermaid width=400}default width is 800 - Theme - Use
{.mermaid theme=forest}default is 'default'. Corresponds to--themeflag of mermaid.cli - Filename - Use
{.mermaid filename="file with space"}to set the filename. This has priority over the caption - Save path - Use
{.mermaid loc=img}default loc=inline which will
encode the image in adata urischeme.- Possible values for
locloc=inline- default; encode image to data uri on img tag.- For widest compatibility, use png (default)
- SVG has trouble on IE11
loc=imgur- upload png to imgur and link to it.loc=<anythingelse>-treat as folder name to place images into
- Possible values for
Note that to specify options, you need to use the curly braces syntax and have the .mermaid class attached.
Admittedly, this is uglier than the earlier syntax on top - but that's how Pandoc wants it.
It's also possible to override global defaults by using environment variables. The name for these environment variables are the same as the attributes prefixed with a MERMAID_FILTER_ so that width would be MERMAID_FILTER_WIDTH.
You can also specify an ID to be applied to the rendered image. This may be useful to use pandoc-crossref or similar packages to reference your diagrams, for example:
```{.mermaid #fig:example}
// Your diagram code here
```
This text has a reference @fig:example which is automatically inserted.
(Note that pandoc-crossref will automatically find and use the caption= option. Also note that the order of applying the filters matters - you must apply mermaid-filter before pandoc-crossref so that pandoc-crossref can find the images.)
JSON and CSS configuration
Mermaid cli allows you to specify additional options in a json configuration file and a css file. mermaid-filter
will look in the current working directory for .mermaid-config.json and .mermaid.css and if found, pass them in to
mermaid cli.
Puppeteer Configuration - mermaid-filter will look in the current working directory for a .puppeteer.json and pass it
on to mermaid cli (-p option of mmdc)if found