--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/contrib/automation/hgautomation/try_server.py	Sat Oct 05 11:21:39 2019 -0400
@@ -0,0 +1,99 @@
+# try_server.py - Interact with Try server
+#
+# Copyright 2019 Gregory Szorc <gregory.szorc@gmail.com>
+#
+# This software may be used and distributed according to the terms of the
+# GNU General Public License version 2 or any later version.
+
+# no-check-code because Python 3 native.
+
+import base64
+import json
+import os
+import subprocess
+import tempfile
+
+from .aws import AWSConnection
+
+LAMBDA_FUNCTION = "ci-try-server-upload"
+
+
+def trigger_try(c: AWSConnection, rev="."):
+    """Trigger a new Try run."""
+    lambda_client = c.session.client("lambda")
+
+    cset, bundle = generate_bundle(rev=rev)
+
+    payload = {
+        "bundle": base64.b64encode(bundle).decode("utf-8"),
+        "node": cset["node"],
+        "branch": cset["branch"],
+        "user": cset["user"],
+        "message": cset["desc"],
+    }
+
+    print("resolved revision:")
+    print("node: %s" % cset["node"])
+    print("branch: %s" % cset["branch"])
+    print("user: %s" % cset["user"])
+    print("desc: %s" % cset["desc"].splitlines()[0])
+    print()
+
+    print("sending to Try...")
+    res = lambda_client.invoke(
+        FunctionName=LAMBDA_FUNCTION,
+        InvocationType="RequestResponse",
+        Payload=json.dumps(payload).encode("utf-8"),
+    )
+
+    body = json.load(res["Payload"])
+    for message in body:
+        print("remote: %s" % message)
+
+
+def generate_bundle(rev="."):
+    """Generate a bundle suitable for use by the Try service.
+
+    Returns a tuple of revision metadata and raw Mercurial bundle data.
+    """
+    # `hg bundle` doesn't support streaming to stdout. So we use a temporary
+    # file.
+    path = None
+    try:
+        fd, path = tempfile.mkstemp(prefix="hg-bundle-", suffix=".hg")
+        os.close(fd)
+
+        args = [
+            "hg",
+            "bundle",
+            "--type",
+            "gzip-v2",
+            "--base",
+            "public()",
+            "--rev",
+            rev,
+            path,
+        ]
+
+        print("generating bundle...")
+        subprocess.run(args, check=True)
+
+        with open(path, "rb") as fh:
+            bundle_data = fh.read()
+
+    finally:
+        if path:
+            os.unlink(path)
+
+    args = [
+        "hg",
+        "log",
+        "-r",
+        rev,
+        # We have to upload as JSON, so it won't matter if we emit binary
+        # since we need to normalize to UTF-8.
+        "-T",
+        "json",
+    ]
+    res = subprocess.run(args, check=True, capture_output=True)
+    return json.loads(res.stdout)[0], bundle_data