Attachments are being corrupted on upload and download

[Ryan J Ollos]

By comparing the MD5 checksums, we are seeing that the downloads are being corrupted. We are seeing them corrupted on move from the path directory to a numbered subdirectory, as well as on download from the site. There may be multiple issues at play here. More information will be provided shortly.

[Radek Bartoň]

Thank you for reporting. What is your operating system and Python version? What was the way how you have added the files to the plugin, trac-admin or web interface? Are you referring to binary or textual files or it happens for every file you upload?

[Ryan J Ollos]

Yeah, my defect report was a bit inadequate; I had been planning to add more info last night, but here it is:

• Server is CentOS 5, Python 2.6, Trac 0.12.2, DownloadsPlugin r11238.
• We've seen the issue when adding files with trac-admin.
• We've seen the issue when download zip and msi files.

I'm going to ask one of my coworkers to follow up with you in more detail. He's working the issue right now.

[pkline]

Following up on what rjollos reported:

We are working with fairly large zip and msi files that are about 60 MB. The first corruption was on some files after adding them through the trac-admin command. The md5sums didn't match between the downloads directory and the numbered directory that the plugin creates and copies them to. Running "zip -T" to test the integrity reported the copy in the downloads directory to be ok and the one in the numbered directory to be an invalid zip file.

Yesterday I added an msi successfully, the files matched between downloads and the numbered directory. I downloaded the msi through the plugin but it wouldn't run. I checked the md5sum of the downloaded file and it didn't match what was in the numbered directory. A second attempt failed as well and showed the file size was off by 2 MB. I downloaded the same file from the numbered directory with WinFTP successfully.

[Ryan J Ollos]

Turns out this was due to configuration of the Apache server. There was a timeout that was causing downloads to be cutoff. No fault of DownloadsPlugin ;)