fix: cache Docker client instead of creating a new one all the time, fixes #5861

[stasadev]

The Issue

• Using Docker API broke Colima/Lima/Rancher usage #5861

How This PR Solves The Issue

Do not create a lot of requests for new Docker client.
Close client connection.

Manual Testing Instructions

I run TestComposerVersion several times on tb-macos-arm64-7, all green:

GOTEST_SHORT=true make testpkg TESTARGS='-run TestComposerVersion --count=1'

Automated Testing Overview

Waiting for Colima tests.

Related Issue Link(s)

Release/Deployment Notes

[github-actions]

Download the artifacts for this pull request:

• all-ddev-executables.zip
• ddev-linux-amd64.zip
• ddev-linux-arm64.zip
• ddev-macos-amd64.zip
• ddev-macos-arm64.zip
• ddev-windows-amd64-installer.zip

See Testing a PR

[rfay]

Let's enable Rancher and macOS amd64 on this PR.

[rfay]

Only TestConfigValidate failed, https://github.com/ddev/ddev/actions/runs/7979112678/job/21785753458?pr=5878

Restarting. This kind of failure is quite common.

[rfay]

Failed again on TestConfigValidate, same thing.

Retry

[rfay]

We may have to use tmate to try TestConfigValidate, or see how it works on tb-macos-arm64-6

[rfay]

Oh look at TestConfigValidate:

func TestConfigValidate(t *testing.T) {
	if nodeps.IsAppleSilicon() {
		t.Skip("Skipping on mac M1 to ignore problems with 'connection reset by peer'")
	}

If I remove the "skip on Apple Silicon" then I get the same failures on my machine using colima:

All project containers are now ready.
    config_test.go:628: 
        	Error Trace:	/Users/rfay/workspace/ddev/pkg/ddevapp/config_test.go:628
        	Error:      	Received unexpected error:
        	            	Get "http://127.0.0.1//readme.html": dial tcp 127.0.0.1:80: connect: connection refused
        	Test:       	TestConfigValidate
    config_test.go:630: 
        	Error Trace:	/Users/rfay/workspace/ddev/pkg/ddevapp/config_test.go:630
        	Error:      	Received unexpected error:
        	            	Get "http://127.0.0.1//readme.html": dial tcp 127.0.0.1:80: connect: connection refused
        	Test:       	TestConfigValidate

These are the lines that are failing:

		_, _, err = testcommon.GetLocalHTTPResponse(t, "http://x.ddev.site/"+staticURI)
		assert.NoError(err)
		_, _, err = testcommon.GetLocalHTTPResponse(t, "http://somethjingrandom.any.ddev.site/"+staticURI)
		assert.NoError(err)

I do not get those failures on Orbstack or Docker Desktop.

I'm pretty sure the exclusion for Apple Silicon was put in there in the early unstable days of Docker Desktop on arm64. Not that it's all that stable now. But it wasn't intended to exclude Colima on arm64.

TestConfigValidate also passes on HEAD with Docker Desktop.
TestConfigValidate FAILS on HEAD with Colima, but it's a bit different, same lines, but it's the EOF error
TestConfigValidate FAILS sometimes but not always on Colima at ca7e2ab (right before API change) in the same way as above (connection refused)

It's possible that this has been a flaky test for colima for a really long time and we might be able to ignore it. It does not appear to be new with this patch.

[rfay]

I'm in favor of adding if IsColima() t.Skip() on TestConfigValidate. I think it's OK.

[rfay]

Yay, it looks like we did finally get a clean colima on 538c5ca

Congratulations. I think TestConfigValidate is just too flaky on Colima so we'll be fine to be rid of it.

[rfay]

Thanks for the amazing work on this. I think we may have almost dug out of that hole :)

[rfay]

Yay, success!

[GuySartorelli]

Amazing work!