Add the fedora-messaging consumer to mirror a pagure project

This commit comes with both the consumer as well as an example
configuration file

Signed-off-by: Pierre-Yves Chibon <pingou@pingoured.fr>

mirror_from_pagure_bus.py

@@ -0,0 +1,118 @@
+"""
+This script runs in a loop and clone or update the clone of the ansible repo
+hosted in pagure.io
+"""
+from __future__ import print_function
+
+import datetime
+import logging
+import os
+import sched
+import subprocess
+import sys
+import time
+
+from fedora_messaging import api, config
+
+
+_log = logging.getLogger(__name__)
+
+
+
+def run_command(command, cwd=None):
+    """ Run the specified command in a specific working directory if one
+    is specified.
+
+    :arg command: the command to run
+    :type command: list
+    :kwarg cwd: the working directory in which to run this command
+    :type cwd: str or None
+    """
+    output = None
+    try:
+        output = subprocess.check_output(command, cwd=cwd, stderr=subprocess.PIPE)
+    except subprocess.CalledProcessError as e:
+        _log.error("Command `%s` return code: `%s`", " ".join(command), e.returncode)
+        _log.error("stdout:\n-------\n%s", e.stdout)
+        _log.error("stderr:\n-------\n%s", e.stderr)
+        raise
+
+    return output
+
+
+class MirrorFromPagure(object):
+    """
+    A fedora-messaging consumer update a local mirror of a repo hosted on
+    pagure.io.
+
+    Three configuration key is used from fedora-messaging's
+    "consumer_config" key:
+     - "mirror_folder", which indicates where mirrors should be store
+     - "urls", which is a list of mirrors to keep up to date
+     - "triggers_name", the fullname of the project (ie: name or namespace/name)
+       that we want to trigger a refresh of our clone on
+
+     ::
+
+        [consumer_config]
+        mirror_folder = "mirrors"
+        trigger_names = ["Fedora-Infra/ansible"]
+        urls = ["https://pagure.io/Fedora-Infra/ansible.git"]
+    """
+
+    def __init__(self):
+        """Perform some one-time initialization for the consumer."""
+        self.path = config.conf["consumer_config"]["mirror_folder"]
+        self.urls = config.conf["consumer_config"]["urls"]
+        self.trigger_names = config.conf["consumer_config"]["trigger_names"]
+
+        if not os.path.exists(self.path):
+            raise OSError("No folder %s found on disk" % self.path)
+
+    def __call__(self, message, cnt=0):
+        """
+        Invoked when a message is received by the consumer.
+
+        Args:
+            message (fedora_messaging.api.Message): The message from AMQP.
+        """
+        _log.info("Received topic: %s", message.topic)
+        if message.topic == "io.pagure.prod.pagure.git.receive":
+            repo_name = message.body.get("repo", {}).get("fullname")
+            if repo_name not in self.trigger_names:
+                _log.info("Not the pagure repo of interest, bailing")
+                return
+        elif message.topic == "org.fedoraproject.prod.infragit.receive":
+            pass
+        else:
+            _log.info("Unexpected topic received: %s", message.topic)
+            return
+
+        try:
+            for url in self.urls:
+                _log.info("Syncing %s", url)
+                name = url.rsplit("/", 1)[-1]
+
+                dest_folder = os.path.join(self.path, name)
+                if not os.path.exists(dest_folder):
+                    _log.info("   Cloning as new %s", url)
+                    cmd = ["git", "clone", "--mirror", url]
+                    run_command(cmd, cwd=self.path)
+
+                _log.info(
+                    "   Running git fetch with transfer.fsckObjects=1 in %s", 
+                    dest_folder
+                )
+                cmd = ["git", "-c", "transfer.fsckObjects=1", "fetch"]
+                run_command(cmd, cwd=dest_folder)
+
+        except Exception:
+            _log.exception("Something happened while calling git")
+            if cnt >= 3:
+                raise
+            _log.info("  Re-running in 10 seconds")
+            time.sleep(10)
+            self.__call__(message, cnt=cnt+1)
+
+
+api.consume(MirrorFromPagure)