A markdown to html converter with sequence diagram and flowchart support. Generating documents including diagrams has advantages:

• Docs can be checked into version control like source code, and can compare changes effectively as it is all text
• Making and updating diagrams using drawing software is slow

It converts markdown codeblocks for diagrams using Graphviz. Pseudocode to Graphviz is inspired by this gist. Pseudocode is converted to dot file and then Graphviz's dot program converts it to vector image.

• Ruby 2.7.6 and up
• Graphviz (tested with dot version 3.0.0)

$ brew install graphviz

$ apt-get install graphviz

$ yum install graphviz

$ gem install markdoc

For bundler add gem markdoc to your Gemfile.

$ markdoc document.md > document.html

Generated html includes inline svg diagrams, eliminating need for attached image files. It provides 3 executables:

• markdoc converts markdown document to html
• pseudo2svg converts pseudocode to svg image (see below for pseudocode format)
• sequence2svg converts sequence diagram spec to svg image(see below for sequence diagram spec format)

Currently it supports only if/else branch logic, but you can achieve a lot with it.

if ConditionN Action-A Action-B else Action-C end 

Include codeblock with pseudo language in your markdown.

```pseudo visit registration page enter email address if new user fill in registration form submit if validation error fix registration form review the fix submit else submit end else enter password if password wrong ask password again else good to go end confirm account info end confirm registration info ``` 

Or you could compile individual pseudocode to vector image. Below is generated by:

$ pseudo2svg examples/example.pseudo > examples/flowchart.svg

Include codeblock with sequence language in your markdown. Sequence diagram starts with actor declaration(becomes symbol of man), then object declaration(becomes big rectangles with vertical lifeline), then follows messages. Message format is:

• A -> B : Label - Arrow from A to B with Label over it. Arrows work either way, so it is equivalent to B <- A : Label
• A <~ B : Label - Dashed arrow representing return message. Also works for other direction. so it is same as B ~> A : Label
• C : Label - Message to C itself. Actually it is same as C -> C : Label

```sequence Student = Actor P = Partner Site App = Web App Api = Reg API Student -> P : Choose course(S) P -> Api : Issue key for(S) P <~ Api : Registration key(K) P -> App : Register with key(K) Student <~ App : Registration form Student -> App : Fill the form(F) App : Save the form(F) App -> Api : Register(K, F) # New API Api : Create course App <~ Api : Course details(C) App : Save(C) Student <~ App : Show course summary Student -> Api : Click study button Student <~ Api : Show mypage ``` 

Or you could compile individual sequence diagram to vector image. Below is generated by:

$ sequence2svg examples/example.sequence > examples/sequence.svg

When printing docs you might want to break pages at specific line. You can use this markup for that:

<p class="page-break"><!-- break --></p>

See examples/doc.md for complete example.

Fork the repo, and send a pull request. I promise I will merge almost all PR's as soon as you don't break existing behaviour. ;) More than welcome if you implement other diagram types. Please add a bit of test for your implementation if you add a feature.

The MIT License (MIT)

Copyright (c) Lkhagva Ochirkhuyag, 2022

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.