Bug 1677020 - Always cap try tasks to a 28 days expiry. r=taskgraph-r…

…eviewers,jmaher

Currently, if a task defines its own expiry with a very large value,
that will be respected even on try, where we actually don't want that to
happen.

This also helps simplify the setup for docker images.

We also take on the occasion to remove the discrepancy between the
default expiry for tasks in general and tests in particular. Bug 1258497
set the original expiry to 14 days, bug 1281004 added another place
where the expiry was set to 14 days for tests specifically, and then bug
1304180 changed the expiry to 28 days, but it just seems the location
for tests was overlooked rather than deliberately left to 14 days.

Differential Revision: https://phabricator.services.mozilla.com/D96962

taskcluster/taskgraph/transforms/docker_image.py

@@ -140,7 +140,7 @@ def fill_template(config, tasks):
                 "image_name": image_name,
                 "artifact_prefix": "public",
             },
-            "expires-after": "28 days" if config.params.is_try() else "1 year",
+            "expires-after": "1 year",
             "scopes": [],
             "treeherder": {
                 "symbol": job_symbol,

taskcluster/taskgraph/transforms/task.py

@@ -40,6 +40,7 @@
     get_release_config,
 )
 from taskgraph.util.signed_artifacts import get_signed_artifacts
+from taskgraph.util.time import value_of
 from taskgraph.util.workertypes import worker_type_implementation
 from voluptuous import Any, Required, Optional, Extra, Match, All, NotIn
 from taskgraph import GECKO, MAX_DEPENDENCIES
@@ -1839,7 +1840,12 @@ def build_task(config, tasks):
                 )
             )
 
-        if "expires-after" not in task:
+        if "expires-after" in task:
+            if config.params.is_try():
+                delta = value_of(task["expires-after"])
+                if delta.days >= 28:
+                    task["expires-after"] = "28 days"
+        else:
             task["expires-after"] = "28 days" if config.params.is_try() else "1 year"
 
         if "deadline-after" not in task:

taskcluster/taskgraph/transforms/tests.py

@@ -939,19 +939,6 @@ def set_tier(config, tasks):
         yield task
 
 
-@transforms.add
-def set_expires_after(config, tasks):
-    """Try jobs expire after 2 weeks; everything else lasts 1 year.  This helps
-    keep storage costs low."""
-    for task in tasks:
-        if "expires-after" not in task:
-            if config.params.is_try():
-                task["expires-after"] = "14 days"
-            else:
-                task["expires-after"] = "1 year"
-        yield task
-
-
 @transforms.add
 def set_download_symbols(config, tasks):
     """In general, we download symbols immediately for debug builds, but only
@@ -1878,7 +1865,9 @@ def make_job_description(config, tasks):
         if task["mozharness"]["requires-signed-builds"] is True:
             jobdesc["dependencies"]["build-signing"] = task["build-signing-label"]
 
-        jobdesc["expires-after"] = task["expires-after"]
+        if "expires-after" in task:
+            jobdesc["expires-after"] = task["expires-after"]
+
         jobdesc["routes"] = []
         jobdesc["run-on-projects"] = sorted(task["run-on-projects"])
         jobdesc["scopes"] = []