Zip files corrupted when downloaded from a docker volume

[vweng]

Bug description

Volume download works for plain text files, but if the file is a zip, somehow the downloaded one cannot be extracted by any zip tools.

Expected behavior

Zip files should be intact after download.

Steps to reproduce the issue:

Steps to reproduce the behavior:

1. create volume and abc.tar.gz file in it:
   [vweng@bugatti ~]$ docker volume create test
   test
   [vweng@bugatti ~]$ docker run -d -it -v test:/test busybox
   1dac573e7ef25406b26429c2d8c24b073709f08e8ac0204502ec0c195e5625e7
   [vweng@bugatti ~]$ docker exec -it 1dac573e7ef2 sh
   / # cd test
   /test # touch abc
   /test # tar zcf abc.tar.gz abc
   /test # ls -l
   total 4
   -rw-r--r-- 1 root root 0 Jan 28 16:46 abc
   -rw-r--r-- 1 root root 86 Jan 28 16:47 abc.tar.gz

2. now go to portainer UI and find the volume "test" and download the abc.tar.gz from browser

3. try open the abc.tar.gz file:
   $ tar zxf abc.tar.gz
   tar: Unrecognized archive format
   tar: Error exit delayed from previous errors.

Technical details:

• Portainer version: 1.20.0
• Docker version (managed by Portainer): 18.03.1-ce, build 9ee9f40
• Platform (windows/linux): linux
• Command used to start Portainer (docker run -p 9000:9000 portainer/portainer):
• Browser: google chrome

Additional context
Add any other context about the problem here.

[DeyV]

The same with mp3 files Portainer-Agent: 1.2.1 , portainer 1.20.2