From 71f8fc209f1dd1859f4eced426d36f3c47c4c685 Mon Sep 17 00:00:00 2001
From: Nikolai R Kristiansen <nikolai.kristiansen@remarkable.no>
Date: Fri, 10 Feb 2023 12:51:07 +0100
Subject: [PATCH 1/2] fix(techdocs-cli): Fix proxying to mkdocs

The domain localhost may point to both 127.0.0.1 and ::1, ipv4 and ipv6
and when node tries to lookup localhost it might prefer ipv6 while mkdocs
is only listening on ipv4. This tells node-proxy to target the ipv4 address
instead of relying on localhost hostname lookup.

Signed-off-by: Nikolai R Kristiansen <nikolai.kristiansen@remarkable.no>
---
 packages/techdocs-cli/src/commands/serve/serve.ts | 2 +-
 packages/techdocs-cli/src/lib/httpServer.ts       | 8 ++++----
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/packages/techdocs-cli/src/commands/serve/serve.ts b/packages/techdocs-cli/src/commands/serve/serve.ts
index 48e48d4f66..b779731fae 100644
--- a/packages/techdocs-cli/src/commands/serve/serve.ts
+++ b/packages/techdocs-cli/src/commands/serve/serve.ts
@@ -127,7 +127,7 @@ export default async function serve(opts: OptionValues) {
   const httpServer = new HTTPServer(
     previewAppPath,
     port,
-    opts.mkdocsPort,
+    mkdocsExpectedDevAddr,
     opts.verbose,
   );
 
diff --git a/packages/techdocs-cli/src/lib/httpServer.ts b/packages/techdocs-cli/src/lib/httpServer.ts
index c4bd5b823a..08987f3f1d 100644
--- a/packages/techdocs-cli/src/lib/httpServer.ts
+++ b/packages/techdocs-cli/src/lib/httpServer.ts
@@ -23,26 +23,26 @@ export default class HTTPServer {
   private readonly proxyEndpoint: string;
   private readonly backstageBundleDir: string;
   private readonly backstagePort: number;
-  private readonly mkdocsPort: number;
+  private readonly mkdocsTargetAddress: string;
   private readonly verbose: boolean;
 
   constructor(
     backstageBundleDir: string,
     backstagePort: number,
-    mkdocsPort: number,
+    mkdocsTargetAddress: string,
     verbose: boolean,
   ) {
     this.proxyEndpoint = '/api/techdocs/';
     this.backstageBundleDir = backstageBundleDir;
     this.backstagePort = backstagePort;
-    this.mkdocsPort = mkdocsPort;
+    this.mkdocsTargetAddress = mkdocsTargetAddress;
     this.verbose = verbose;
   }
 
   // Create a Proxy for mkdocs server
   private createProxy() {
     const proxy = httpProxy.createProxyServer({
-      target: `http://localhost:${this.mkdocsPort}`,
+      target: this.mkdocsTargetAddress,
     });
 
     return (request: http.IncomingMessage): [httpProxy, string] => {

From dcacf94912bb733202eb945c66a802c12f800cb5 Mon Sep 17 00:00:00 2001
From: Nikolai R Kristiansen <nikolai.kristiansen@remarkable.no>
Date: Fri, 10 Feb 2023 13:09:50 +0100
Subject: [PATCH 2/2] docs: Add changeset

Signed-off-by: Nikolai R Kristiansen <nikolai.kristiansen@remarkable.no>
---
 .changeset/flat-lizards-poke.md | 10 ++++++++++
 1 file changed, 10 insertions(+)
 create mode 100644 .changeset/flat-lizards-poke.md

diff --git a/.changeset/flat-lizards-poke.md b/.changeset/flat-lizards-poke.md
new file mode 100644
index 0000000000..bc180836fa
--- /dev/null
+++ b/.changeset/flat-lizards-poke.md
@@ -0,0 +1,10 @@
+---
+'@techdocs/cli': patch
+---
+
+Fix proxying to mkdocs
+
+The domain localhost may point to both 127.0.0.1 and ::1, ipv4 and ipv6
+and when node tries to lookup localhost it might prefer ipv6 while mkdocs
+is only listening on ipv4. This tells node-proxy to target the ipv4 address
+instead of relying on localhost hostname lookup.