api: Move the API package to a dedicated subdirectory.

In order to keep all three packages (zulip, zulip_bots,
zulip_botserver) in the same repo, all package files must now
be nested one level deeper.

For instance, python-zulip-api/zulip_bots/zulip_bots/bots/, instead
of python-zulip-api/zulip_bots/bots/.

zulip/integrations/zephyr/zephyr_mirror.py

@@ -0,0 +1,93 @@
+#!/usr/bin/env python
+# Copyright (C) 2012 Zulip, Inc.
+#
+# Permission is hereby granted, free of charge, to any person
+# obtaining a copy of this software and associated documentation files
+# (the "Software"), to deal in the Software without restriction,
+# including without limitation the rights to use, copy, modify, merge,
+# publish, distribute, sublicense, and/or sell copies of the Software,
+# and to permit persons to whom the Software is furnished to do so,
+# subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be
+# included in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+# BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+# ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+# CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+from __future__ import absolute_import
+from __future__ import print_function
+import sys
+import subprocess
+import os
+import traceback
+import signal
+
+sys.path[:0] = [os.path.dirname(__file__)]
+from zephyr_mirror_backend import parse_args
+
+(options, args) = parse_args()
+
+sys.path[:0] = [os.path.join(options.root_path, 'api')]
+
+from types import FrameType
+from typing import Any
+
+def die(signal, frame):
+    # type: (int, FrameType) -> None
+
+    # We actually want to exit, so run os._exit (so as not to be caught and restarted)
+    os._exit(1)
+
+signal.signal(signal.SIGINT, die)
+
+from zulip import RandomExponentialBackoff
+
+args = [os.path.join(options.root_path, "user_root", "zephyr_mirror_backend.py")]
+args.extend(sys.argv[1:])
+
+if options.sync_subscriptions:
+    subprocess.call(args)
+    sys.exit(0)
+
+if options.forward_class_messages and not options.noshard:
+    sys.path.append("/home/zulip/zulip")
+    if options.on_startup_command is not None:
+        subprocess.call([options.on_startup_command])
+    from zerver.lib.parallel import run_parallel
+    print("Starting parallel zephyr class mirroring bot")
+    jobs = list("0123456789abcdef")
+
+    def run_job(shard):
+        # type: (str) -> int
+        subprocess.call(args + ["--shard=%s" % (shard,)])
+        return 0
+    for (status, job) in run_parallel(run_job, jobs, threads=16):
+        print("A mirroring shard died!")
+        pass
+    sys.exit(0)
+
+backoff = RandomExponentialBackoff(timeout_success_equivalent=300)
+while backoff.keep_going():
+    print("Starting zephyr mirroring bot")
+    try:
+        subprocess.call(args)
+    except Exception:
+        traceback.print_exc()
+    backoff.fail()
+
+
+error_message = """
+ERROR: The Zephyr mirroring bot is unable to continue mirroring Zephyrs.
+This is often caused by failing to maintain unexpired Kerberos tickets
+or AFS tokens.  See https://zulipchat.com/zephyr for documentation on how to
+maintain unexpired Kerberos tickets and AFS tokens.
+"""
+print(error_message)
+sys.exit(1)