Cake: Zip doesn't preserve file permissions on Linux

[johncrim]

What You Are Seeing?

Using something like:

Zip(Directory("d"), File("test.zip"));

The zip file contents are correct, but linux file permissions (ugoa rwx) are not preserved within the zip file, when run on Linux.

What is Expected?

I should be able to list the zip file contents using unzip -Zl and see the linux file permissions that were set before zipping.

What version of Cake are you using?

dotnet core
cake.tool version '0.34.1'

Are you running on a 32 or 64 bit system?

64 bit

What environment are you running on? Windows? Linux? Mac?

Linux

Are you running on a CI Server? If so, which one?

Yes, but I see the same results running locally.

How Did You Get This To Happen? (Steps to Reproduce)

1. Create a script file on Linux:

mkdir d
echo '#!/bin/bash' > d/test.sh 
echo "echo foo" >> d/test.sh 
chmod a+x d/test.sh

1. Write a build.cake script to zip the directory:
   ```c#
   Zip(Directory("d"), File("test.zip"));

3. Install the cake.tool
```bash
dotnet tool install -g cake.tool

1. Run the cake script

dotnet cake

1. Check the contents of the zipped file:

$ unzip -Zl test.zip
Archive:  test.zip
Zip file size: 135 bytes, number of entries: 1
?---------  2.0 unx       21 b-       23 defN 19-Aug-05 14:13 test.sh
1 file, 21 bytes uncompressed, 23 bytes compressed:  -9.5%

In contrast, if the zip file is created with the linux zip command (infozip), the file contents are:

$ unzip -Zl linux-test.zip
Archive:  linux-test.zip
Zip file size: 185 bytes, number of entries: 1
-rwxrwxrwx  3.0 unx       21 tx       21 stor 19-Aug-05 14:13 test.sh
1 file, 21 bytes uncompressed, 21 bytes compressed:  0.0%

which shows that the file permissions are preserved in the zip file.

[devlead]

AFAIK as I know this is partially a limitation of .NET ZipEntry ( see dotnet/corefx#17342 )

There's work arounds i.e.

const int rw_rw_r = (0x8000 + 0x0100 + 0x0080 + 0x0020 + 0x0010 + 0x0004) << 16;
entry.ExternalAttributes = rw_rw_r;

would set read write / read write / read,

Code for zipping in cake is located here
https://github.com/cake-build/cake/blob/develop/src/Cake.Common/IO/Zipper.cs#L165-L192

Issue would be to in a clean way identify running on posix and identify correct file permissions for each file while guaranteeing to work with existing scripts.

[gitfool]

Looks like you'd probably want to use the Mono.Posix.NETStandard NuGet package.

• Source: mono/mono/tree/master/mcs/class/Mono.Posix
• FilePermissions: search FilePermissions path:mcs/class/Mono.Posix

[devlead]

@gitfool yip probably, but unsure/need to evaluate if we want to take that dependency, probably a good use case to test in an addin first and promote to Cake itself once battle tested.

[augustoproiete]

Link to the issue on the dotnet/runtime repo: Compression.ZipFile support for Unix Permissions.