[PATCH v2 1/1] git-p4: auto-delete named temporary file

From: Andrey Mazo <ahippo@yandex.ru>
Date: Aug 27, 2019, 03:43 UTC
Message-ID: <7e59b5cec2f267820feeeeb63a20814fe67d61e3.1566876175.git.ahippo@yandex.com>
In-Reply-To: <pull.303.v2.git.gitgitgadget@gmail.com>

From: "Philip.McGraw" <Philip.McGraw@bentley.com>

Avoid double-open exceptions on Windows platform when calculating for lfs compressed size threshold (git-p4.largeFileCompressedThreshold) comparisons.

Take new approach using the NamedTemporaryFile() file-like object as input to the ZipFile() which auto-deletes after implicit close leaving with scope.

Original code had double-open exception on Windows platform because file still open from NamedTemporaryFile() using generated filename instead of object.

Thanks to Andrey for patiently suggesting several iterations on this change for avoiding exceptions!

Also print error details after resulting IOError to make debugging cause of exception less mysterious when it has nothing to do with "git version recent enough."

Signed-off-by: Philip.McGraw <Philip.McGraw@bentley.com>
Reviewed-by: Andrey Mazo <ahippo@yandex.com>
---
 git-p4.py | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/git-p4.py b/git-p4.py
index c71a6832e2..33bdb14fd1 100755
--- a/git-p4.py
+++ b/git-p4.py
@@ -1158,17 +1158,15 @@ def exceedsLargeFileThreshold(self, relPath, contents):
         if gitConfigInt('git-p4.largeFileCompressedThreshold'):
             contentsSize = sum(len(d) for d in contents)
             if contentsSize <= gitConfigInt('git-p4.largeFileCompressedThreshold'):
                 return False
             contentTempFile = self.generateTempFile(contents)
-            compressedContentFile = tempfile.NamedTemporaryFile(prefix='git-p4-large-file', delete=False)
-            zf = zipfile.ZipFile(compressedContentFile.name, mode='w')
-            zf.write(contentTempFile, compress_type=zipfile.ZIP_DEFLATED)
-            zf.close()
-            compressedContentsSize = zf.infolist()[0].compress_size
+            compressedContentFile = tempfile.NamedTemporaryFile(prefix='git-p4-large-file', delete=True)
+            with zipfile.ZipFile(compressedContentFile, mode='w') as zf:
+                zf.write(contentTempFile, compress_type=zipfile.ZIP_DEFLATED)
+                compressedContentsSize = zf.infolist()[0].compress_size
             os.remove(contentTempFile)
-            os.remove(compressedContentFile.name)
             if compressedContentsSize > gitConfigInt('git-p4.largeFileCompressedThreshold'):
                 return True
         return False
 
     def addLargeFile(self, relPath):
@@ -3512,12 +3510,13 @@ def importHeadRevision(self, revision):
         details["time"] = res["time"]
 
         self.updateOptionDict(details)
         try:
             self.commit(details, self.extractFilesFromCommit(details), self.branch)
-        except IOError:
+        except IOError as err:
             print("IO error with git fast-import. Is your git version recent enough?")
+            print("IO error details: {}".format(err))
             print(self.gitError.read())
 
     def openStreams(self):
         self.importProcess = subprocess.Popen(["git", "fast-import"],
                                               stdin=subprocess.PIPE,

base-commit: 1feeaaf26bff51996f9f96c6dc41ca0f95ab5fc4
Pull-Request: https://github.com/gitgitgadget/git/pull/303

-- 
2.21.0