From 533480005d44f2c5d20903cf93e6e80a562cd180 Mon Sep 17 00:00:00 2001
From: Paul Weidner <paul.weidner@gmail.com>
Date: Sun, 12 Dec 2021 22:54:25 -0800
Subject: [PATCH 1/3] Add gitRemote webLink to page as sourceLink.

---
 gatsby-node.js | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/gatsby-node.js b/gatsby-node.js
index 04c8089..6b0b945 100644
--- a/gatsby-node.js
+++ b/gatsby-node.js
@@ -80,6 +80,13 @@ exports.createPages = async ({ graphql, actions }) => {
               pathname
               sourceInstanceName
             }
+            parent {
+              ... on File {
+                gitRemote {
+                  webLink
+                }
+              }
+            }
           }
         }
       }
@@ -94,6 +101,7 @@ exports.createPages = async ({ graphql, actions }) => {
         // in page queries as GraphQL variables.
         pathname: node.fields.pathname,
         sourceInstanceName: node.fields.sourceInstanceName,
+        sourceLink: node?.parent?.gitRemote?.webLink
       },
     });
   });

From e5bf9a18006218d1d9090ef74496da05ea54484c Mon Sep 17 00:00:00 2001
From: Paul Weidner <paul.weidner@gmail.com>
Date: Sun, 12 Dec 2021 22:54:48 -0800
Subject: [PATCH 2/3] Render a source link above the toc.

---
 src/components/table-of-contents.js | 7 ++++++-
 src/templates/docs-page.js          | 7 ++++++-
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/src/components/table-of-contents.js b/src/components/table-of-contents.js
index 79364d5..3cd91b5 100644
--- a/src/components/table-of-contents.js
+++ b/src/components/table-of-contents.js
@@ -36,11 +36,16 @@ const useStyles = makeStyles(theme => ({
 
 export default function TableOfContents(props) {
   const classes = useStyles();
-  const { __html, headings, title = 'Table of contents' } = props;
+  const { __html, headings, source, title = 'Table of contents' } = props;
 
   const [tocRef, setActiveHeading] = useActiveHeading(headings, classes.active);
 
   return (<>
+    <h3>
+        <a href={source.sourceLink} style={{ textDecoration: 'none' }}>
+          {source.sourceInstanceName} source
+        </a>
+    </h3>
     <Typography component='label' className={classes.title}>{title}</Typography>
     <Box
       ref={tocRef}
diff --git a/src/templates/docs-page.js b/src/templates/docs-page.js
index 96bc87a..db53e5c 100644
--- a/src/templates/docs-page.js
+++ b/src/templates/docs-page.js
@@ -31,13 +31,18 @@ const useStyles = makeStyles({
   },
 });
 
-export default function DocsPage({ data }) {
+export default function DocsPage({ data, pageContext }) {
   const classes = useStyles();
 
   const { markdownRemark: post } = data;
+  const { sourceInstanceName, sourceLink } = pageContext;
   const [tocHtml, setTocHtml] = useState(post.tableOfContents);
   const title = post.headings.find(({ depth }) => depth === 1)?.value;
   const toc = {
+    source: {
+      sourceInstanceName,
+      sourceLink,
+    },
     title,
     __html: tocHtml,
     headings: post.headings

From 68425469e0f681cc6c0e194264d30714ee4667b3 Mon Sep 17 00:00:00 2001
From: Paul Weidner <paul.weidner@gmail.com>
Date: Sun, 12 Dec 2021 23:11:59 -0800
Subject: [PATCH 3/3] Remove optional chaining.

---
 gatsby-node.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/gatsby-node.js b/gatsby-node.js
index 6b0b945..5dfdbc9 100644
--- a/gatsby-node.js
+++ b/gatsby-node.js
@@ -93,6 +93,7 @@ exports.createPages = async ({ graphql, actions }) => {
     }
   `);
   result.data.allMarkdownRemark.edges.forEach(({ node }) => {
+    const sourceLink = node.parent.gitRemote ? node.parent.gitRemote.webLink : null;
     createPage({
       path: node.fields.pathname,
       component: path.resolve(`./src/templates/docs-page.js`),
@@ -101,7 +102,7 @@ exports.createPages = async ({ graphql, actions }) => {
         // in page queries as GraphQL variables.
         pathname: node.fields.pathname,
         sourceInstanceName: node.fields.sourceInstanceName,
-        sourceLink: node?.parent?.gitRemote?.webLink
+        sourceLink,
       },
     });
   });