Added Mermaid graphical markup extension to Sphinx

Author: iangillingham-stfc

doc/Editing-the-Wiki.md

@@ -100,6 +100,41 @@ You can then add the image in markdown using the URL `test.png`:
 
     ![alternative text](test.png)
 
+## Mermaid Diagrams
+Mermaid diagrams can be added using the following syntax (example):
+```
+```{mermaid}
+---
+title: Simple sample
+---
+stateDiagram-v2
+    [*] --> Document
+    Develop_software --> Document
+    Document --> Develop_software
+    Develop_software --> Test_software
+    Test_software --> Crash
+    Crash --> Develop_software
+    Test_software --> [*]
+```
+
+will render as:
+```{mermaid}
+---
+title: Simple sample
+---
+stateDiagram-v2
+    [*] --> Document
+    Document --> Develop_software
+    Develop_software --> Document
+    Develop_software --> Test_software
+    Test_software --> Crash
+    Crash --> Develop_software
+    Test_software --> [*]
+```
+
+
+The Mermaid syntax is documented [here](https://mermaid.js.org/intro/syntax-reference.html).
+
 ## Spellchecking
 
 The wiki has a built-in spellchecker, which will automatically run when a commit

doc/conf.py

@@ -41,6 +41,10 @@
     "sphinx.ext.viewcode",
     # Redirects
     "sphinx_reredirects",
+    # Mermaid diagrams
+    "sphinxcontrib.mermaid",
+    # Graphvis diagrams
+    "sphinx.ext.graphviz",
 ]
 napoleon_google_docstring = True
 napoleon_numpy_docstring = False

pyproject.toml

@@ -32,6 +32,7 @@ dependencies = [
   "sphinxcontrib-spelling",
   "sphinx-reredirects",
   "pytest",
+  "sphinxcontrib-mermaid"
 ]
 
 [project.optional-dependencies]