From 86f2346165890fdb47f130876ff0f0a16c425362 Mon Sep 17 00:00:00 2001
From: Kay Faraday <iexoo7ahth8s@freak.university>
Date: Thu, 21 Sep 2023 07:23:34 +0000
Subject: [PATCH] initial commit

---
 .gitignore           |  2 ++
 fingerd.example.toml |  8 ++++++
 fingerd.py           | 64 ++++++++++++++++++++++++++++++++++++++++++++
 fingerd.toml         |  2 ++
 requirements.txt     |  2 ++
 5 files changed, 78 insertions(+)
 create mode 100644 .gitignore
 create mode 100644 fingerd.example.toml
 create mode 100755 fingerd.py
 create mode 100644 fingerd.toml
 create mode 100644 requirements.txt

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..a230a78
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+.venv/
+__pycache__/
diff --git a/fingerd.example.toml b/fingerd.example.toml
new file mode 100644
index 0000000..19daef4
--- /dev/null
+++ b/fingerd.example.toml
@@ -0,0 +1,8 @@
+instance_name = 'freak.university'
+
+[db]
+# Accepts all parameters accepted by https://magicstack.github.io/asyncpg/current/api/index.html#connection.
+# Or leave this section blank to use the defaults.
+username='mastodon'
+password='...'
+database='...'
diff --git a/fingerd.py b/fingerd.py
new file mode 100755
index 0000000..546441c
--- /dev/null
+++ b/fingerd.py
@@ -0,0 +1,64 @@
+#!/usr/bin/env python
+
+import os
+import asyncio
+import asyncpg
+import qtoml as toml
+from contextvars import ContextVar
+
+FINGER_PORT = 79
+MASTODON_USERNAME_MAX_LENGTH = 30
+
+db = ContextVar('db')
+
+with open('fingerd.toml') as f:
+	config = toml.load(f)
+
+async def handle_finger(reader, writer):
+	try:
+		data = await reader.read(
+			len('@') * 2
+			+ MASTODON_USERNAME_MAX_LENGTH
+			+ len(config['instance_name'])
+		)
+		handle = data.decode().rstrip()
+		username = handle.removeprefix('@').removesuffix('@' + config['instance_name'])
+		if '@' in username:
+			writer.write(b'Error: user must be local to this instance\n')
+			writer.write(username.encode())
+			writer.write(b'\n')
+			writer.write(config['instance_name'].encode())
+			writer.write(b'\n')
+			return
+
+		resp = await db.get().fetchval(
+			'SELECT note FROM accounts WHERE username = $1 AND domain IS NULL',
+			username,
+		)
+		if resp is None:
+			writer.write(b'Error: user not found\n')
+			return
+
+		writer.write(resp.encode())
+		writer.write(b'\n')
+	finally:
+		print('running cleanup')
+		await writer.drain()
+		writer.close()
+		await writer.wait_closed()
+
+async def main():
+	db.set(await asyncpg.create_pool(**config['db']))
+
+	async with await asyncio.start_server(
+		handle_finger,
+		'0.0.0.0',
+		os.getenv('PORT', FINGER_PORT),
+	) as server:
+		addrs = ', '.join(str(sock.getsockname()) for sock in server.sockets)
+		print(f'Serving on {addrs}')
+
+		await server.serve_forever()
+
+if __name__ == '__main__':
+	asyncio.run(main())
diff --git a/fingerd.toml b/fingerd.toml
new file mode 100644
index 0000000..372e32e
--- /dev/null
+++ b/fingerd.toml
@@ -0,0 +1,2 @@
+instance_name = 'freak.university'
+[db]
diff --git a/requirements.txt b/requirements.txt
new file mode 100644
index 0000000..602cab9
--- /dev/null
+++ b/requirements.txt
@@ -0,0 +1,2 @@
+asyncpg ~= 0.28.0
+qtoml ~= 0.3.1