Add builder to project descriptor

[sambhav]

Signed-off-by: Sambhav Kothari skothari44@bloomberg.net

Summary

Adds support for the builder key in project descriptor

Output

Before

After

Documentation

• Should this change be documented?
  • Yes, see #___
  • No

Related

Resolves #1114
Implements buildpacks/rfcs#138 (We should wait for that to be merged before merging this I guess?)

[sambhav]

This ended up being a bit weird to implement than I imagined.

We needed to do 2 things -

1. Figure out if the user explicitly passed a flag or the default one was used.
2. Parse the project descriptor and check if builder existed before before we could validate the bulder flag. In order to do so, I moved the builder validation out of validate flags as it was sort of a chicken egg problem where I had to use the project descriptor from the flags and parse it before I could validate the actual flags and that seemed to break the whole contract of validating the flags before using them. So for now I extracted this part out of validate flags and I explicitly check and throw an error if builder is null.

[sambhav]

I also had to parse the builder and decide which one to use in the command instead of the client.Build as at that point it was too late to distinguish which flag was passed and the order of preference.

[codecov]

Codecov Report

Merging #1116 (dc94db0) into main (e00ee4a) will decrease coverage by 0.52%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main    #1116      +/-   ##
==========================================
- Coverage   80.52%   80.00%   -0.51%     
==========================================
  Files         136      136              
  Lines        8243     6005    -2238     
==========================================
- Hits         6637     4804    -1833     
+ Misses       1176      767     -409     
- Partials      430      434       +4     

Flag	Coverage Δ
os_linux	79.97% <100.00%> (-0.02%)	⬇️
os_macos	77.49% <100.00%> (-0.02%)	⬇️
os_windows	100.00% <ø> (+19.57%)	⬆️
unit	80.00% <100.00%> (+0.02%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

[dfreilich]

This is great! One small concern is that we don't have a unit test for the case where a default builder was previously set in the config, but we test it in our acceptance tests here (

pack/acceptance/acceptance_test.go

Lines 798 to 936 in dc94db0

	when("default builder is set", func() {
	it.Before(func() {
	pack.RunSuccessfully("config", "default-builder", builderName)
	pack.JustRunSuccessfully("config", "trusted-builders", "add", builderName)
	})
	it("creates a runnable, rebuildable image on daemon from app dir", func() {
	appPath := filepath.Join("testdata", "mock_app")
	output := pack.RunSuccessfully(
	"build", repoName,
	"-p", appPath,
	)
	assertOutput := assertions.NewOutputAssertionManager(t, output)
	assertOutput.ReportsSuccessfulImageBuild(repoName)
	assertOutput.ReportsUsingBuildCacheVolume()
	assertOutput.ReportsSelectingRunImageMirror(runImageMirror)
	t.Log("app is runnable")
	assertImage.RunsWithOutput(repoName, "Launch Dep Contents", "Cached Dep Contents")
	t.Log("it uses the run image as a base image")
	assertImage.HasBaseImage(repoName, runImage)
	t.Log("sets the run image metadata")
	assertImage.HasLabelWithData(repoName, "io.buildpacks.lifecycle.metadata", fmt.Sprintf(`"stack":{"runImage":{"image":"%s","mirrors":["%s"]}}}`, runImage, runImageMirror))
	t.Log("registry is empty")
	assertImage.NotExistsInRegistry(repo)
	t.Log("add a local mirror")
	localRunImageMirror := registryConfig.RepoName("pack-test/run-mirror")
	imageManager.TagImage(runImage, localRunImageMirror)
	defer imageManager.CleanupImages(localRunImageMirror)
	pack.JustRunSuccessfully("config", "run-image-mirrors", "add", runImage, "-m", localRunImageMirror)
	t.Log("rebuild")
	output = pack.RunSuccessfully(
	"build", repoName,
	"-p", appPath,
	)
	assertOutput = assertions.NewOutputAssertionManager(t, output)
	assertOutput.ReportsSuccessfulImageBuild(repoName)
	assertOutput.ReportsSelectingRunImageMirrorFromLocalConfig(localRunImageMirror)
	cachedLaunchLayer := "simple/layers:cached-launch-layer"
	assertLifecycleOutput := assertions.NewLifecycleOutputAssertionManager(t, output)
	assertLifecycleOutput.ReportsRestoresCachedLayer(cachedLaunchLayer)
	assertLifecycleOutput.ReportsExporterReusingUnchangedLayer(cachedLaunchLayer)
	assertLifecycleOutput.ReportsCacheReuse(cachedLaunchLayer)
	t.Log("app is runnable")
	assertImage.RunsWithOutput(repoName, "Launch Dep Contents", "Cached Dep Contents")
	t.Log("rebuild with --clear-cache")
	output = pack.RunSuccessfully("build", repoName, "-p", appPath, "--clear-cache")
	assertOutput = assertions.NewOutputAssertionManager(t, output)
	assertOutput.ReportsSuccessfulImageBuild(repoName)
	assertLifecycleOutput = assertions.NewLifecycleOutputAssertionManager(t, output)
	assertLifecycleOutput.ReportsSkippingBuildpackLayerAnalysis()
	assertLifecycleOutput.ReportsExporterReusingUnchangedLayer(cachedLaunchLayer)
	assertLifecycleOutput.ReportsCacheCreation(cachedLaunchLayer)
	t.Log("cacher adds layers")
	assert.Matches(output, regexp.MustCompile(`(?i)Adding cache layer 'simple/layers:cached-launch-layer'`))
	t.Log("inspecting image")
	inspectCmd := "inspect"
	if !pack.Supports("inspect") {
	inspectCmd = "inspect-image"
	}
	var (
	webCommand string
	helloCommand string
	helloArgs []string
	helloArgsPrefix string
	)
	if imageManager.HostOS() == "windows" {
	webCommand = ".\\run"
	helloCommand = "cmd"
	helloArgs = []string{"/c", "echo hello world"}
	helloArgsPrefix = " "
	} else {
	webCommand = "./run"
	helloCommand = "echo"
	helloArgs = []string{"hello", "world"}
	helloArgsPrefix = ""
	}
	formats := []compareFormat{
	{
	extension: "txt",
	compareFunc: assert.TrimmedEq,
	outputArg: "human-readable",
	},
	{
	extension: "json",
	compareFunc: assert.EqualJSON,
	outputArg: "json",
	},
	{
	extension: "yaml",
	compareFunc: assert.EqualYAML,
	outputArg: "yaml",
	},
	{
	extension: "toml",
	compareFunc: assert.EqualTOML,
	outputArg: "toml",
	},
	}
	for _, format := range formats {
	t.Logf("inspecting image %s format", format.outputArg)
	output = pack.RunSuccessfully(inspectCmd, repoName, "--output", format.outputArg)
	expectedOutput := pack.FixtureManager().TemplateFixture(
	fmt.Sprintf("inspect_image_local_output.%s", format.extension),
	map[string]interface{}{
	"image_name": repoName,
	"base_image_id": h.ImageID(t, runImageMirror),
	"base_image_top_layer": h.TopLayerDiffID(t, runImageMirror),
	"run_image_local_mirror": localRunImageMirror,
	"run_image_mirror": runImageMirror,
	"web_command": webCommand,
	"hello_command": helloCommand,
	"hello_args": helloArgs,
	"hello_args_prefix": helloArgsPrefix,
	},
	)
	format.compareFunc(output, expectedOutput)
	}
	})

) so it's ok.