add get_build_metadata function (#31923)

* version

* Get build metadata

* two lines

* channel

* cwd

* default to unknown

* dataclass
old-commit-hash: 38d03b997958effea805a6c3860d2c5edaf2ae65

system/version.py

@@ -1,17 +1,22 @@
 #!/usr/bin/env python3
+from dataclasses import dataclass
+import json
 import os
+import pathlib
 import subprocess
 
 
 from openpilot.common.basedir import BASEDIR
 from openpilot.common.swaglog import cloudlog
 from openpilot.common.utils import cache
-from openpilot.common.git import get_origin, get_branch, get_short_branch, get_normalized_origin, get_commit_date
+from openpilot.common.git import get_commit, get_origin, get_branch, get_short_branch, get_normalized_origin, get_commit_date
 
 
 RELEASE_BRANCHES = ['release3-staging', 'release3', 'nightly']
 TESTED_BRANCHES = RELEASE_BRANCHES + ['devel', 'devel-staging']
 
+BUILD_METADATA_FILENAME = "build.json"
+
 training_version: bytes = b"0.2.0"
 terms_version: bytes = b"2"
 
@@ -75,6 +80,41 @@ def is_dirty() -> bool:
   return dirty
 
 
+@dataclass(frozen=True)
+class OpenpilotMetadata:
+  version: str
+  release_notes: str
+  git_commit: str
+
+
+@dataclass(frozen=True)
+class BuildMetadata:
+  channel: str
+  openpilot: OpenpilotMetadata
+
+
+
+def get_build_metadata(path: str = BASEDIR) -> BuildMetadata | None:
+  build_metadata_path = pathlib.Path(path) / BUILD_METADATA_FILENAME
+
+  if build_metadata_path.exists():
+    build_metadata = json.loads(build_metadata_path.read_text())
+    openpilot_metadata = build_metadata.get("openpilot", {})
+
+    channel = build_metadata.get("channel", "unknown")
+    version = openpilot_metadata.get("version", "unknown")
+    release_notes = openpilot_metadata.get("release_notes", "unknown")
+    git_commit = openpilot_metadata.get("git_commit", "unknown")
+    return BuildMetadata(channel, OpenpilotMetadata(version, release_notes, git_commit))
+
+  git_folder = pathlib.Path(path) / ".git"
+
+  if git_folder.exists():
+    return BuildMetadata(get_short_branch(path), OpenpilotMetadata(get_version(path), get_release_notes(path), get_commit(path)))
+
+  return None
+
+
 if __name__ == "__main__":
   from openpilot.common.params import Params