Add flask app

2 files changed, 85 insertions, 0 deletions

diff --git a/ddns.cfg b/ddns.cfg
new file mode 100644
index 0000000..3628b53
--- /dev/null
+++ b/ddns.cfg
@@ -0,0 +1,6 @@
+AMAZON_KEY_ID = ""
+AMAZON_SECRET_KEY = ""
+
+# These are bearer tokens, care should be taken not to expose them
+# on the web.
+CLIENTS = {}
diff --git a/ddns.py b/ddns.py
new file mode 100644
index 0000000..5fa7c8c
--- /dev/null
+++ b/ddns.py
@@ -0,0 +1,79 @@
+#!/usr/bin/env python
+
+import os
+import flask
+import hashlib
+import functools
+from boto.route53.record import ResourceRecordSets
+from boto.route53.connection import Route53Connection
+
+
+app = flask.Flask(__name__)
+app.config.from_pyfile("/etc/ddns.cfg", silent=True)
+app.config.from_pyfile("ddns.cfg", silent=True)
+if "AMAZON_KEY_ID" not in app.config:
+    raise Exception("Not configured")
+
+
+def returns_plain_text(f):
+    @functools.wraps(f)
+    def wrapper(*args, **kwargs):
+        return flask.Response(f(*args, **kwargs), content_type="text/plain")
+
+    return wrapper
+
+
+def update_record(zone, record, ip):
+    conn = Route53Connection(app.config["AMAZON_KEY_ID"],
+            app.config["AMAZON_SECRET_KEY"])
+    change_set = ResourceRecordSets(conn, conn.get_zone(zone).id)
+    change_set.add_change("UPSERT", record, type="A", ttl=60).add_value(ip)
+    change_set.commit()
+
+
+@app.errorhandler(404)
+@app.errorhandler(405)
+@app.errorhandler(500)
+def handle_error(ex):
+    response = flask.Response("Error", content_type="text/plain")
+    response.status_code = getattr(ex, "code", 500)
+    return response
+
+
+@app.route("/new-secret", methods=["GET"])
+@returns_plain_text
+def new_secret():
+    return hashlib.sha256(os.urandom(100)).hexdigest()
+
+
+@app.route("/update", methods=["POST"])
+def update_ip():
+    key = flask.request.form.get("key")
+    config = app.config["CLIENTS"].get(key)
+
+    if not config:
+        flask.abort(404)
+
+    try:
+        update_record(config["zone"], config["resource"],
+                flask.request.remote_addr)
+        return "OK"
+    except:
+        flask.abort(500)
+
+
+@app.route("/", methods=["GET"])
+@returns_plain_text
+def get_ip():
+    return flask.request.remote_addr
+
+
+@app.route("/config")
+@returns_plain_text
+def get_config():
+    return repr(app.config.items())
+
+
+if __name__ == "__main__":
+    app.debug = True
+    app.run()