fetch key from WKD

setup.cfg

@@ -18,6 +18,8 @@ python_requires = >=3.11
 install_requires =
     deltachat-rpc-client
     deltachat-rpc-server
+    wkdhash
+    requests
 
 [options.packages.find]
 where = src
@@ -26,6 +28,10 @@ where = src
 console_scripts =
     keyserver-bot = keyserver_bot.hooks:main
 
+[options.extras_require]
+dev =
+    pytest
+
 [tox:tox]
 envlist = lint, py311, py312
 isolated_build = True

src/keyserver_bot/hooks.py

@@ -1,11 +1,10 @@
 #!/usr/bin/env python3
-"""Minimal echo bot example.
-
-it will echo back any text send to it, it also will print to console all Delta Chat core events.
-Pass --help to the CLI to see available options.
-"""
 from deltachat_rpc_client import events, run_bot_cli
 
+import wkd
+import koo
+import vcard
+
 hooks = events.HookCollection()
 
 
@@ -17,7 +16,19 @@ def log_event(event):
 @hooks.on(events.NewMessage)
 def echo(event):
     snapshot = event.message_snapshot
-    snapshot.chat.send_text(snapshot.text)
+    email = snapshot
+    domain = email.split("@")[1]
+    public_key = wkd.request_by_email(email, domain)
+    if not public_key:
+        public_key = wkd.request_by_email(email, f"openpgpkey.{domain}")
+        if not public_key:
+            public_key = wkd.request_by_email(email, "wkd.keys.openpgp.org")
+            if not public_key:
+                snapshot.chat.send_text("Sorry, I could not find a key for this user.")
+                return
+
+    vcard_path = vcard.save_vcard(public_key)
+    snapshot.chat.send_file(vcard_path)
 
 
 def main():

src/keyserver_bot/vcard.py

@@ -0,0 +1,16 @@
+
+def construct_vcard(email: str, public_key: str) -> str:
+    """
+
+    :param email:
+    :param public_key:
+    :return:
+    """
+
+
+def save_vcard(content: str) -> str:
+    """
+
+    :param content: the VCard content
+    :return: the file path in the blob dir
+    """

src/keyserver_bot/wkd.py

@@ -0,0 +1,18 @@
+import wkdhash
+import requests
+import base64
+
+
+def request_by_email(email: str, server: str) -> str:
+    """Request the public key from WKD by email
+
+    :param email: an RFC 5322 email address
+    :return: the public key of the user, or "" if it isn't found
+    """
+    localpart, domain = email.split("@")
+    wkd_hash = wkdhash.userid_to_wkd_hash(email)
+    wkd_url = f"https://{server}/.well-known/openpgpkey/{domain}/hu/{wkd_hash}?l={localpart}"
+    r = requests.get(wkd_url)
+    if b"The requested URL was not found on this server." in r.content:
+        return ""
+    return base64.b64encode(r.content).decode().strip()

tests/test_wkd.py

@@ -0,0 +1,13 @@
+import pytest
+import keyserver_bot.wkd
+
+
+@pytest.mark.parametrize(
+    ("email", "server", "public_key"),
+    [
+        ("sdjif2mlij@protonmail.com", "openpgpkey.protonmail.com", "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"),
+        ("missytake@systemli.org", "openpgpkey.systemli.org", "")
+    ],
+)
+def test_request_by_email(email, server, public_key):
+    assert public_key == keyserver_bot.wkd.request_by_email(email, server)