From 1b781bb0c1b806d541a01df6607e177134a74935 Mon Sep 17 00:00:00 2001
From: Jan De Dobbeleer <jan.de.dobbeleer@gmail.com>
Date: Fri, 28 Apr 2023 11:12:25 +0200
Subject: [PATCH] docs: add webfinger API

---
 website/api/webfinger/function.json | 18 +++++++
 website/api/webfinger/index.js      | 83 +++++++++++++++++++++++++++++
 website/staticwebapp.config.json    |  9 +++-
 3 files changed, 109 insertions(+), 1 deletion(-)
 create mode 100644 website/api/webfinger/function.json
 create mode 100644 website/api/webfinger/index.js

diff --git a/website/api/webfinger/function.json b/website/api/webfinger/function.json
new file mode 100644
index 00000000..c7642f69
--- /dev/null
+++ b/website/api/webfinger/function.json
@@ -0,0 +1,18 @@
+{
+  "bindings": [
+    {
+      "authLevel": "anonymous",
+      "type": "httpTrigger",
+      "direction": "in",
+      "name": "req",
+      "methods": [
+        "get"
+      ]
+    },
+    {
+      "type": "http",
+      "direction": "out",
+      "name": "res"
+    }
+  ]
+}
diff --git a/website/api/webfinger/index.js b/website/api/webfinger/index.js
new file mode 100644
index 00000000..df2a0dd8
--- /dev/null
+++ b/website/api/webfinger/index.js
@@ -0,0 +1,83 @@
+// GET https://${MASTODON_DOMAIN}/.well-known/webfinger?resource=acct:${MASTODON_USER}@${MASTODON_DOMAIN}
+
+function trimPrefix(str, prefix) {
+  if (str.startsWith(prefix)) {
+    return str.slice(prefix.length)
+  }
+  return str
+}
+
+function webfinger(username) {
+  return {
+    "subject": `acct:${username}@hachyderm.io`,
+    "aliases": [
+      `https://hachyderm.io/@${username}`,
+      `https://hachyderm.io/users/${username}`
+    ],
+    "links": [
+      {
+        "rel": "http://webfinger.net/rel/profile-page",
+        "type": "text/html",
+        "href": `https://hachyderm.io/@${username}`
+      },
+      {
+        "rel": "self",
+        "type": "application/activity+json",
+        "href": `https://hachyderm.io/users/${username}`
+      },
+      {
+        "rel": "http://ostatus.org/schema/1.0/subscribe",
+        "template": "https://hachyderm.io/authorize_interaction?uri={uri}"
+      }
+    ]
+  };
+}
+
+module.exports = async function (context, req) {
+  context.log('Webfinger function processed a request');
+
+  try {
+    let resource = req.query.resource;
+    if (!resource) {
+      resource = "jan@social.ohmyposh.dev";
+    }
+
+    resource = trimPrefix(resource, "acct:");
+
+    context.log(`Creating Mastodon user info for ${resource}`);
+
+    let body;
+
+    switch (resource) {
+      case "releasebot@social.ohmyposh.dev":
+        body = webfinger("releasebot");
+        break;
+      case "jan@social.ohmyposh.dev":
+        body = webfinger("jandedobbeleer");
+        break;
+      default:
+        context.log(`Unknown resource: ${resource}`);
+        context.res = {
+          body: "Unknown resource",
+          status: 400
+        };
+        return;
+    }
+
+    // return body as application/jrd+json
+    context.res = {
+      body: body,
+      headers: {
+        "Content-Type": "application/jrd+json"
+      }
+    };
+  } catch (error) {
+    context.log(error);
+    context.res = {
+      body: {
+        "message": (error.message) ? error.message : "unable to create webfinger"
+      },
+      status: 500
+    };
+  }
+}
diff --git a/website/staticwebapp.config.json b/website/staticwebapp.config.json
index 1a262873..fa423426 100644
--- a/website/staticwebapp.config.json
+++ b/website/staticwebapp.config.json
@@ -1,5 +1,12 @@
 {
   "platform": {
     "apiRuntime": "node:16"
-  }
+  },
+  "routes": [
+    {
+      "route": "/.well-known/webfinger*",
+      "methods": ["GET"],
+      "rewrite": "/api/webfinger"
+    }
+  ]
 }