setup-go action should allow for existing cache files

[shaunco]

Description:
On a self-hosted runner that is already caching tools, the v4 setup-go action attempts to call tar to extract its mod cache and ends up with a bunch of "Cannot open: File exists" errors, and eventually

Action version:
v4

Platform:

• Ubuntu
• macOS
• Windows

Runner type:

• Hosted
• Self-hosted

Tools version:
^1.20

Repro steps:

Run actions/setup-go@v4
  with:
    go-version: ^1.[2](https://github.com/xyz/abc/actions/runs/123/job/123#step:5:2)0
    check-latest: false
    token: ***
    cache: true
  env:
    GO111MODULE: on
    GOPRIVATE: github.com/xyz/*
    SSH_AUTH_SOCK: /tmp/ssh-XXXXXX/agent.1965
    SSH_AGENT_PID: 1966
Setup go version spec ^1.20
Found in cache @ /opt/hostedtoolcache/go/1.20.6/x64
Added go to the path
Successfully set up Go version ^1.20
/opt/hostedtoolcache/go/1.20.6/x64/bin/go env GOMODCACHE
/opt/hostedtoolcache/go/1.20.6/x64/bin/go env GOCACHE
/home/runner/go/pkg/mod
/home/runner/.cache/go-build
Received 4194[3](https://github.com/xyz/abc/actions/runs/123/job/123#step:5:3)0[4](https://github.com/xyz/abc/actions/runs/123/job/123#step:5:4) of 9246941[5](https://github.com/xyz/abc/actions/runs/123/job/123#step:5:5)4 (0.5%), 4.0 MBs/sec
Received 11324[6](https://github.com/xyz/abc/actions/runs/123/job/123#step:5:6)208 of 924694154 (12.2%), 54.0 MBs/sec
Received 205520896 of 924694154 (22.2%), 65.3 MBs/sec
Received 3103[7](https://github.com/xyz/abc/actions/runs/123/job/123#step:5:7)[8](https://github.com/xyz/abc/actions/runs/123/job/123#step:5:8)4[9](https://github.com/xyz/abc/actions/runs/123/job/123#step:5:9)6 of 924694154 (33.6%), 74.0 MBs/sec
Received 427819008 of 924694154 (46.3%), 81.6 MBs/sec
Received 536870912 of 924694154 (58.1%), 85.3 MBs/sec
Received 666894336 of 924694154 (72.1%), 90.8 MBs/sec
Received 771751936 of 924694154 (83.5%), 91.9 MBs/sec
Received 872415232 of 924694154 (94.3%), 92.3 MBs/sec
Received 924694154 of 924694154 ([10](https://github.com/xyz/abc/actions/runs/123/job/123#step:5:10)0.0%), 93.3 MBs/sec
Cache Size: ~882 MB (924694[15](https://github.com/xyz/abc/actions/runs/123/job/123#step:5:16)4 B)
/usr/bin/tar -xf /home/runner/work/_temp/c44c4bfb-8a98-491b-b4a7-2f38e4fd677c/cache.tzst -P -C /home/runner/work/abc/abc--use-compress-program unzstd
/usr/bin/tar: ../../../go/pkg/mod/go.temporal.io/sdk@v1.15.0/interceptor/tracing_interceptor.go: Cannot open: File exists
/usr/bin/tar: ../../../go/pkg/mod/go.temporal.io/sdk@v1.15.0/interceptor/tracing_interceptor_test.go: Cannot open: File exists
.
.
.
/usr/bin/tar: Exiting with failure status due to previous errors
Warning: Failed to restore: "/usr/bin/tar" failed with error: The process '/usr/bin/tar' failed with exit code 2
Cache is not found

Expected behavior:
Existing files should be ignored via the -k or --skip-old-files option on tar

Actual behavior:
Existing files are treated as errors.

[dusan-trickovic]

Hello @shaunco ! Thank you for reporting the issue, we will investigate it and get back to you as soon as we have more info :)

[shaunco]

Thanks @dusan-trickovic ! Not sure if it is related, but we also seem to end up with quite a few duplicate setup-go action caches that all have the same sha256 and need to be cleared out every few days:

[dsame]

Hello @shaunco,
can you please try to disable caching for the action:

  - uses: actions/setup-go@v4
    with:
      go-version: '...'
      cache: false

this should solve the problem.

[bc-lee]

Based on my understanding, go get downloads source codes with write permissions removed. As a result, extracting (tar -xf) cache files to GOPATH may cause errors. It would be helpful for setup-go to add write permissions to the cache directory before extracting and remove them after the process is complete.

[dsame]

@bc-lee Self-hosted runner preserves the cache and builds results so caching does not have sense for them, we should disable caching for them by default. Currently it can be turned off manually

[bc-lee]

@dsame Aha, that makes sense. I'm not sure if changing the default based on where the runner is running (i.e., provided by GitHub or self-hosted) is a good idea. I think it would be much better for the user to explicitly specify that option.

[dsame]

Hello @bc-lee my motivation to have the different value of cache is to have the same omitted cache input for both github-hosted and self-hosted builds in the other case users have to have to diffrenet workflows