optimize cached file locations and add option for cache directory

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)