Fix failure when using capital letters in image alias in 'FROM ... AS…' instruction

[antechrestos]

Fixes #770
Fixes #592

Description

The third library moby/buildkit lowers the image alias used in FROM image AS alias instruction.
This change fixes this issue by making the resolution of dependencies agnostic to text case.

Submitter Checklist

These are the criteria that every PR should meet, please check them off as you
review them:

• Includes unit tests
• Adds integration tests if needed(not needed to my mind as unit tests cover this fix).

See the contribution guide for more details.

Reviewer Notes

• The code flow looks good.
• Unit tests and or integration tests added.

Release Notes

Given a user use a mounting instruction such as FROM my-image as myImage, when the users reference this image from a command "COPY -- from myImage", kaniko currently fails. This fix aims to make kaniko agnostic to letter case as it is the case of the vendor library moby/buildkit. 

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[antechrestos]

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[antechrestos]

@tejal29 Apparently the integration tests are failing. Yet I cannot access the details link. No matter I read the integration tests, I have not figured which of them fails as none of them uses a capital letter in its COPY -- from instruction

Can you share the failure as I don't have a GCS bucket.

PS:

I fixed the link
http://fusion/runanalysis/info/prod%3Aruntimes-common%2Fkaniko%2Fpresubmit/prod%3Aruntimes-common%2Fkaniko%2Fpresubmit/KOKORO/60fbcd60-3ea1-4248-a7ca-d8dccac51a0a/0/prod%3Aruntimes-common%2Fkaniko%2Fpresubmit/Targets

By replacing it with

http://fusion.corp.google.com/runanalysis/info/prod%3Aruntimes-common%2Fkaniko%2Fpresubmit/prod%3Aruntimes-common%2Fkaniko%2Fpresubmit/KOKORO/60fbcd60-3ea1-4248-a7ca-d8dccac51a0a/0/prod%3Aruntimes-common%2Fkaniko%2Fpresubmit/Targets

Yet I do not have a login 😄

[antechrestos]

@tejal29 don't know if previous kokoro launch ended with the same output but locally I have difficulties launching integration tests

[antechrestos]

@tejal29 @cvgw Is it possible to trigger a kokoro check? I cannot test it from my computer as I reported before.... 😢

[antechrestos]

@cvgw Thank you Is it possible to get the output?

Thank you by advance :)

[cvgw]

@antechrestos looks like one test failed

--- FAIL: TestRelativePaths (0.00s)
    --- FAIL: TestRelativePaths/test_relative_Dockerfile_test_copy (7.00s)
        integration_test.go:406: diff = [
              {
                "Image1": "gcr.io/kaniko-test/docker-dockerfile_test_copy",
                "Image2": "gcr.io/kaniko-test/kaniko-dockerfile_test_copy",
                "DiffType": "File",
                "Diff": {
                  "Adds": [
                    {
                      "Name": "/dir/cache",
                      "Size": 0
                    },
                    {
                      "Name": "/newdir/cache",
                      "Size": 0
                    }
                  ],
                  "Dels": [
                    {
                      "Name": "/dir/dockerfiles/Dockerfile_test_add_dest_symlink_dir",
                      "Size": 61
                    },
                    {
                      "Name": "/newdir/dockerfiles/Dockerfile_test_add_dest_symlink_dir",
                      "Size": 61
                    }
                  ],
                  "Mods": null
                }
              },
              {
                "Image1": "gcr.io/kaniko-test/docker-dockerfile_test_copy",
                "Image2": "gcr.io/kaniko-test/kaniko-dockerfile_test_copy",
                "DiffType": "Metadata",
                "Diff": {
                  "Adds": [],
                  "Dels": []
                }
              }
            ]
        integration_test.go:409: []integration.diffOutput differ (-got, +want): {[]integration.diffOutput}[0].Diff.Adds:
            	-: []integration.fileDiff{{Name: "/dir/cache"}, {Name: "/newdir/cache"}}
            	+: []integration.fileDiff(nil)
            {[]integration.diffOutput}[0].Diff.Dels:
            	-: []integration.fileDiff{{Name: "/dir/dockerfiles/Dockerfile_test_add_dest_symlink_dir", Size: 61}, {Name: "/newdir/dockerfiles/Dockerfile_test_add_dest_symlink_dir", Size: 61}}
            	+: []integration.fileDiff(nil)
FAIL

[antechrestos]

@cvgw Thank you 😄
Now I am puzzled 🤔

[antechrestos]

@cvgw I launched the failed test on my laptop and it passed

❯go test -v --bucket $GCS_BUCKET --repo $IMAGE_REPO -test.run RelativePaths
2019/11/29 00:42:36 Creating tarball of integration test files to use as build context
2019/11/29 00:42:36 Uploading file at /tmp/buce8373/788886540/context_1574984556922350732.tar.gz to GCS bucket at gs://antechrestos-test-kaniko//tmp/buce8373/788886540/context_1574984556922350732.tar.gz
Building kaniko image
Building cache warmer image
Building onbuild base image
Pushing onbuild base image
Building hardlink base image
Pushing hardlink base image
...
=== RUN   TestRelativePaths
=== RUN   TestRelativePaths/test_relative_Dockerfile_test_copy
=== PAUSE TestRelativePaths/test_relative_Dockerfile_test_copy
=== CONT  TestRelativePaths/test_relative_Dockerfile_test_copy
--- PASS: TestRelativePaths (0.00s)
    --- PASS: TestRelativePaths/test_relative_Dockerfile_test_copy (13.47s)
        integration_test.go:406: diff = [
              {
                "Image1": "gcr.io/silent-caster-258821/antechrestos-test-kaniko/docker-dockerfile_test_copy",
                "Image2": "gcr.io/silent-caster-258821/antechrestos-test-kaniko/kaniko-dockerfile_test_copy",
                "DiffType": "File",
                "Diff": {
                  "Adds": null,
                  "Dels": null,
                  "Mods": null
                }
              },
              {
                "Image1": "gcr.io/silent-caster-258821/antechrestos-test-kaniko/docker-dockerfile_test_copy",
                "Image2": "gcr.io/silent-caster-258821/antechrestos-test-kaniko/kaniko-dockerfile_test_copy",
                "DiffType": "Metadata",
                "Diff": {
                  "Adds": [],
                  "Dels": []
                }
              }
            ]
PASS
ok  	github.com/GoogleContainerTools/kaniko/integration	360.027s
❯ git log --oneline | head -1
8e0a566 Fix failure when using capital letters in image alias in 'FROM ... AS' instruction

What can make the result differ?

Thanks

[antechrestos]

@cvgw I made it, my build passed! 😃
I also rebased my code on master branch

[cvgw]

Thanks @antechrestos, looks good!