1 files changed, 77 insertions, 0 deletions
diff --git a/python/mozbuild/mozbuild/vendor/host_base.py b/python/mozbuild/mozbuild/vendor/host_base.py
new file mode 100644
index 0000000000..2484d82e09
--- /dev/null
+++ b/python/mozbuild/mozbuild/vendor/host_base.py
@@ -0,0 +1,77 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, # You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import os
+import subprocess
+import tempfile
+import urllib
+
+
+class BaseHost:
+    def __init__(self, manifest):
+        self.manifest = manifest
+        self.repo_url = urllib.parse.urlparse(self.manifest["vendoring"]["url"])
+
+    def upstream_tag(self, revision):
+        """Temporarily clone the repo to get the latest tag and timestamp"""
+        with tempfile.TemporaryDirectory() as temp_repo_clone:
+            starting_directory = os.getcwd()
+            os.chdir(temp_repo_clone)
+            subprocess.run(
+                [
+                    "git",
+                    "clone",
+                    "-c",
+                    "core.autocrlf=input",
+                    self.manifest["vendoring"]["url"],
+                    self.manifest["origin"]["name"],
+                ],
+                stdout=subprocess.PIPE,
+                stderr=subprocess.PIPE,
+                universal_newlines=True,
+                check=True,
+            )
+            os.chdir("/".join([temp_repo_clone, self.manifest["origin"]["name"]]))
+            if revision == "HEAD":
+                tag = subprocess.run(
+                    ["git", "--no-pager", "tag", "--sort=creatordate"],
+                    stdout=subprocess.PIPE,
+                    stderr=subprocess.PIPE,
+                    universal_newlines=True,
+                    check=True,
+                ).stdout.splitlines()[-1]
+            else:
+                try:
+                    tag = subprocess.run(
+                        ["git", "--no-pager", "tag", "-l", revision],
+                        stdout=subprocess.PIPE,
+                        stderr=subprocess.PIPE,
+                        universal_newlines=True,
+                        check=True,
+                    ).stdout.splitlines()[-1]
+                except IndexError:  # 0 lines of output, the tag does not exist
+                    raise Exception(f"Requested tag {revision} not found in source.")
+
+            tag_timestamp = subprocess.run(
+                [
+                    "git",
+                    "log",
+                    "-1",
+                    "--date=iso8601-strict",
+                    "--format=%ad",
+                    tag,
+                ],
+                stdout=subprocess.PIPE,
+                stderr=subprocess.PIPE,
+                universal_newlines=True,
+                check=True,
+            ).stdout.splitlines()[-1]
+            os.chdir(starting_directory)
+            return tag, tag_timestamp
+
+    def upstream_snapshot(self, revision):
+        raise Exception("Unimplemented for this subclass...")
+
+    def upstream_path_to_file(self, revision, filepath):
+        raise Exception("Unimplemented for this subclass...")