Replace the XML-RPC operations in the `report_mirror` client and the server by a REST API.

[abompard]

The Flask XML-RPC library dependency is unmaintained, has been forked, and the forked is unmaintained as well.
There's a single operation that only takes a file as argument, it could easily be replaced by a "REST" (rather, HTTP) API with an single POST-only endpoint.

[sdglitched]

Hey, I would like to give this a try. Could you please assign it to me if its up for grabs?

I had a question, is their a way to test the implementation of XML-RPC? This will help me figuring out the correct implementation for the REST.

[abompard]

Yeah, the script report_mirror in client is the XML-RPC client, you can use it to test the server part.

[sdglitched]

@abompard, I'm thinking something in lines of below changes in report_mirror

mirrormanager2/client/report_mirror

Line 224 in 4d3020b

def main():

         if data is not None:
-            try:
-                result = requests.post(item.config["global"]["server"], data)
-                print(result.)
-            except OSError as m:
-                print("Error checking in: %s.  Please try again later." % (m[1]))
-            except xmlrpclib.ProtocolError:
-                print(
-                    "Error checking in: Service Temporarily "
-                    "Unavailable.  Please try again later."
-                )
-                sys.exit(1)
-            except xmlrpclib.Fault:
-                print(
-                    "Error checking in.  Connection closed before "
-                    "checkin complete.  Please try again later."
-                )
-                sys.exit(1)
+            response = requests.post(
+                item.config["global"]["server"],
+                json={"data": data},
+                headers={"Content-Type": "application/json"}
+            )
+            if response.status_code == 200:
+                print("Success:", response.json())
+            else:
+                print("Error:", response.json())

Also, a new endpoint in api.py

@views.route("/checkin", methods=["POST"])
def checkin():
    """REST API endpoint to replace XML-RPC checkin functionality."""
    try:
        # Get data from request
        if flask.request.is_json:
            pickledata = flask.request.get_json()
        else:
            pickledata = flask.request.get_data()

        if not pickledata:
            return flask.jsonify({"error": "Missing data parameter"}), 400

        is_pickle = False
        uncompressed = bz2.decompress(base64.urlsafe_b64decode(pickledata))
        try:
            config = json.loads(uncompressed)
        except ValueError:
            logging.info("Fell back to pickle")
            is_pickle = True
            config = pickle.loads(uncompressed)

        r, host, message = read_host_config(DB.session, config)

        if r is not None:
            logging.info(f"Checkin for host {host} (pickle:{is_pickle}) successful: {message}")
            return flask.jsonify({
                "success": True,
                "message": message + "checked in successful"
            }), 200
        else:
            logging.error(f"Error for host {host} (pickle:{is_pickle}) during checkin: {message}")
            return flask.jsonify({
                "success": False,
                "error": message + "error checking in"
            }), 400
    except Exception as e:
        logging.error(f"Checkin error: {e}")
        return flask.jsonify({
            "success": False,
            "error": f"Internal server error: {str(e)}"
        }), 500

Does this seems a good starting point? Actually I'm a bit confused about what kind of data is being sent and how to /xmlrpc endpoint handels it.

If my implementation feels ok - let me know, I'll raise a PR and we can take it from there.

[abompard]

Yeah that's a good start. You can drop pickle support in the server side, I think it was there for historic reasons: the older client was sending pickle and we can't force users to upgrade, but since we're starting over with REST then we can drop pickle support.
Thinking about that, I think we should add a version key in the JSON blob, at the top level, to be able to upgrade the format over time (we'd start at 1). We could even go as far as adding jsonschema-based validation, but let's keep that for later.
I'm waiting for your PR :-)