Merge pull request 'implement file caching' (#11) from file-cache into main

Reviewed-on: https://gitea.opensuse.org/importers/git-importer/pulls/11

git-importer.py

@@ -52,6 +52,13 @@ def main():
         type=pathlib.Path,
         help="Local git repository directory",
     )
+    parser.add_argument(
+        "-c",
+        "--cachedir",
+        required=False,
+        type=pathlib.Path,
+        help="Local cache directory",
+    )
     parser.add_argument(
         "-g",
         "--gc",
@@ -93,9 +100,12 @@ def main():
     if not args.repodir:
         args.repodir = pathlib.Path("repos") / args.package
 
+    if not args.cachedir:
+        args.cachedir = pathlib.Path("~/.cache/git-import/").expanduser()
+
     importer = Importer(URL_OBS, "openSUSE:Factory", args.package)
     importer.import_into_db()
-    exporter = GitExporter(URL_OBS, "openSUSE:Factory", args.package, args.repodir)
+    exporter = GitExporter(URL_OBS, "openSUSE:Factory", args.package, args.repodir, args.cachedir)
     exporter.set_gc_interval(args.gc)
     exporter.export_as_git()
 

lib/git_exporter.py

@@ -12,7 +12,7 @@ from lib.tree_builder import TreeBuilder
 
 
 class GitExporter:
-    def __init__(self, api_url, project, package, repodir):
+    def __init__(self, api_url, project, package, repodir, cachedir):
         self.obs = OBS()
         self.project = project
         self.package = package
@@ -26,6 +26,7 @@ class GitExporter:
         ).create()
         self.state_file = os.path.join(self.git.path, ".git", "_flat_state.yaml")
         self.gc_interval = 200
+        self.cachedir = cachedir
 
     def download(self, revision):
         obs_files = self.obs.files(revision.project, revision.package, revision.srcmd5)
@@ -40,10 +41,7 @@ class GitExporter:
 
         # Download each file in OBS if it is not a binary (or large)
         # file
-        for (name, size, file_md5) in obs_files:
-            # Validate the MD5 of the downloaded file
-            if md5(self.git.path / name) != file_md5:
-                raise Exception(f"Download error in {name}")
+        for name in obs_files:
             self.git.add(name)
 
     def set_gc_interval(self, gc):
@@ -121,6 +119,7 @@ class GitExporter:
                     file.name,
                     flat.commit.expanded_srcmd5,
                     self.git.path,
+                    self.cachedir,
                     file_md5=md5,
                 )
                 self.git.add(file)

lib/obs.py

@@ -1,9 +1,12 @@
 import errno
 import logging
+import shutil
 import time
 import urllib.parse
 import xml.etree.ElementTree as ET
 from urllib.error import HTTPError
+from pathlib import Path
+from lib.proxy_sha256 import md5
 
 import osc.core
 
@@ -158,10 +161,21 @@ class OBS:
         name: str,
         revision: str,
         dirpath: str,
+        cachedir: str,
         file_md5: str,
     ) -> None:
-        with (dirpath / name).open("wb") as f:
-            f.write(self._download(project, package, name, revision).read())
+        
+        cached_file = self._path_from_md5(name, cachedir, file_md5)
+        if not self.in_cache(name, cachedir, file_md5):
+            with (dirpath / name).open("wb") as f:
+                f.write(self._download(project, package, name, revision).read())
+            shutil.copy(dirpath / name, cached_file)
+        else:
+            shutil.copy(cached_file, dirpath / name)
+
+        # Validate the MD5 of the downloaded file
+        if md5(dirpath / name) != file_md5:
+            raise Exception(f"Download error in {name}")
 
     def list(self, project, package, srcmd5, linkrev):
         params = {"rev": srcmd5, "expand": "1"}
@@ -179,3 +193,11 @@ class OBS:
             raise e
 
         return root
+
+    def _path_from_md5(self, name, cachedir, md5):
+        filepath = cachedir / md5[:3]
+        filepath.mkdir(parents=True, exist_ok=True)
+        return filepath / md5[3:]
+
+    def in_cache(self, name, cachedir, md5):
+        return self._path_from_md5(name, cachedir, md5).exists()