contrib: a small script to nudge lingering diff

After a discussion on IRC with various reviewers. It seems like a good idea to
have some automatic cleanup of old, inactive diffs.

Here is a small script able to do so. I am preparing to unleash it on our
phabricator instance.

contrib/phab-clean.py

@@ -0,0 +1,93 b''
+#!/usr/bin/env python
+#
+# A small script to automatically reject idle Diffs
+#
+# you need to set the PHABBOT_USER and PHABBOT_TOKEN environment variable for authentication
+from __future__ import absolute_import, print_function
+
+import datetime
+import os
+import sys
+
+import phabricator
+
+MESSAGE = """There seems to have been no activities on this Diff for the past 3 Months.
+
+By policy, we are automatically moving it out of the `need-review` state.
+
+Please, move it back to `need-review` without hesitation if this diff should still be discussed.
+
+:baymax:need-review-idle:
+"""
+
+
+PHAB_URL = "https://phab.mercurial-scm.org/api/"
+USER = os.environ.get("PHABBOT_USER", "baymax")
+TOKEN = os.environ.get("PHABBOT_TOKEN")
+
+
+NOW = datetime.datetime.now()
+
+# 3 months in seconds
+DELAY = 60 * 60 * 24 * 30 * 3
+
+
+def get_all_diff(phab):
+    """Fetch all the diff that the need review"""
+    return phab.differential.query(
+        status="status-needs-review",
+        order="order-modified",
+        paths=[('HG', None)],
+    )
+
+
+def filter_diffs(diffs, older_than):
+    """filter diffs to only keep the one unmodified sin <older_than> seconds"""
+    olds = []
+    for d in diffs:
+        modified = int(d['dateModified'])
+        modified = datetime.datetime.fromtimestamp(modified)
+        d["idleFor"] = idle_for = NOW - modified
+        if idle_for.total_seconds() > older_than:
+            olds.append(d)
+    return olds
+
+
+def nudge_diff(phab, diff):
+    """Comment on the idle diff and reject it"""
+    diff_id = int(d['id'])
+    phab.differential.createcomment(
+        revision_id=diff_id, message=MESSAGE, action="reject"
+    )
+
+
+if not USER:
+    print(
+        "not user specified please set PHABBOT_USER and PHABBOT_TOKEN",
+        file=sys.stderr,
+    )
+elif not TOKEN:
+    print(
+        "not api-token specified please set PHABBOT_USER and PHABBOT_TOKEN",
+        file=sys.stderr,
+    )
+    sys.exit(1)
+
+phab = phabricator.Phabricator(USER, host=PHAB_URL, token=TOKEN)
+phab.connect()
+phab.update_interfaces()
+print('Hello "%s".' % phab.user.whoami()['realName'])
+
+diffs = get_all_diff(phab)
+print("Found %d Diffs" % len(diffs))
+olds = filter_diffs(diffs, DELAY)
+print("Found %d old Diffs" % len(olds))
+for d in olds:
+    diff_id = d['id']
+    status = d['statusName']
+    modified = int(d['dateModified'])
+    idle_for = d["idleFor"]
+    msg = 'nudging D%s in "%s" state for %s'
+    print(msg % (diff_id, status, idle_for))
+    # uncomment to actually affect phab
+    nudge_diff(phab, d)

tests/test-check-module-imports.t

@@ -24,6 +24,7 b' outputs, which should be fixed later.'
   > -X contrib/packaging/hg-docker \
   > -X contrib/packaging/hgpackaging/ \
   > -X contrib/packaging/inno/ \
+  > -X contrib/phab-clean.py \
   > -X contrib/python-zstandard/ \
   > -X contrib/win32/hgwebdir_wsgi.py \
   > -X contrib/perf-utils/perf-revlog-write-plot.py \