Remember first failed build URL and display it in cached failures

Signed-off-by: magic_rb <[email protected]>

Author: MagicRB

buildbot_nix/__init__.py

@@ -193,14 +193,15 @@ def schedule_eval_failure(self, job: NixEvalJobError) -> tuple[str, Properties]:
         return (self.failed_eval_scheduler, props)
 
     def schedule_cached_failure(
-        self, job: NixEvalJobSuccess, first_failure: datetime
+        self, job: NixEvalJobSuccess, first_failure: datetime, first_failure_url: str,
     ) -> tuple[str, Properties]:
         source = "nix-eval-nix"
 
         props = BuildTrigger.set_common_properties(
             Properties(), self.project, source, job
         )
         props.setProperty("first_failure", str(first_failure), source)
+        props.setProperty("first_failure_url", first_failure_url, source)
 
         return (self.cached_failure_scheduler, props)
 
@@ -475,12 +476,13 @@ def run(self) -> Generator[Any, Any, None]:
                 elif failed_build is not None and self.build.reason != "rebuild":
                     scheduler_log.addStdout(
                         f"\t- skipping {build.attr} due to cached failure, first failed at {failed_build.time}\n"
+                        + f"\t  see build at {failed_build.url}\n"
                     )
                     build_schedule_order.remove(build)
 
                     brids, results_deferred = yield self.schedule(
                         ss_for_trigger,
-                        *self.schedule_cached_failure(build, failed_build.time),
+                        *self.schedule_cached_failure(build, failed_build.time, failed_build.url),
                     )
                     scheduled.append(
                         BuildTrigger.ScheduledJob(build, brids, results_deferred)
@@ -543,7 +545,9 @@ def run(self) -> Generator[Any, Any, None]:
             # if it failed, remove all dependent jobs, schedule placeholders and add them to the list of scheduled jobs
             if isinstance(job, NixEvalJobSuccess):
                 if result != SUCCESS:
-                    failed_builds.add_build(job.drvPath, datetime.now(tz=UTC))
+                    if self.build.reason == "rebuild" or not failed_builds.check_build(job.drvPath):
+                      url = yield self.build.getUrl()
+                      failed_builds.add_build(job.drvPath, datetime.now(tz=UTC), url)
 
                     removed = self.get_failed_dependents(
                         job, build_schedule_order, job_closures
@@ -731,6 +735,7 @@ def run(self) -> Generator[Any, object, int]:
                 [
                     f"{attr} was failed because it has failed previously and its failure has been cached.",
                     f"  first failure time: {self.getProperty('first_failure')}",
+                    f"  first failure url: {self.getProperty('first_failure_url')}",
                 ]
             )
             + "\n"

buildbot_nix/failed_builds.py

@@ -3,7 +3,7 @@
 from pathlib import Path
 from typing import TYPE_CHECKING, Any
 
-from pydantic import BaseModel
+from pydantic import BaseModel, Field
 
 if TYPE_CHECKING:
     database: None | dbm._Database = None
@@ -18,6 +18,7 @@ class FailedBuildsError(Exception):
 class FailedBuild(BaseModel):
     derivation: str
     time: datetime
+    url: str = Field(default="unknown")
 
 
 DB_NOT_INIT_MSG = "Database not initialized"
@@ -30,12 +31,12 @@ def initialize_database(db_path: Path) -> None:
         database = dbm.open(str(db_path), "c")
 
 
-def add_build(derivation: str, time: datetime) -> None:
+def add_build(derivation: str, time: datetime, url: str) -> None:
     global database  # noqa: PLW0602
 
     if database is not None:
         database[derivation] = FailedBuild(
-            derivation=derivation, time=time
+            derivation=derivation, time=time, url=url
         ).model_dump_json()
     else:
         raise FailedBuildsError(DB_NOT_INIT_MSG)