Use pr default tag together with user provided tags (#11981)

* Use config to provide a default tag for images build for pr or commit.
Added validation tag field to provide validation regex together with a tag.
Update kaniko-build-config.yaml to provide default tag for pr and commit images with validation regex.
Validating tag when parsing it's value.
Added TagOption to add PR number to the Tagger instance.
Using pull request default tag together with user provided tags instead replacing all values with default tag. This allows users to provide their own tag to the images build on pr.

* Do not set base sha for pull request images.
Set only tagger fields needed for image type.
Fix validation regex for commit to align with expected date format.
Return error from TagOption to signal problems with setting it.
Checking if pr or sha strings passed to TagOption is empty. Return error when trying to set empty string.

* Use config to provide a default tag for images build for pr or commit.
Added validation tag field to provide validation regex together with a tag.
Update kaniko-build-config.yaml to provide default tag for pr and commit images with validation regex.
Validating tag when parsing it's value.
Added TagOption to add PR number to the Tagger instance.
Using pull request default tag together with user provided tags instead replacing all values with default tag. This allows users to provide their own tag to the images build on pr.

* Do not set base sha for pull request images.
Set only tagger fields needed for image type.
Fix validation regex for commit to align with expected date format.
Return error from TagOption to signal problems with setting it.
Checking if pr or sha strings passed to TagOption is empty. Return error when trying to set empty string.

* Adjusting tests

* Updated tests to verify changed features.
Small fixes in application.

* Aligned DateFormat TagOption to check for empty format string.
Added tests for options.

* Test getDefaultTag function.

* Remove test custom unmarshaller.

* Keep old tag template definition for migration purposes.

* Config will be changed together with gh action in separate PR.

cmd/image-builder/config.go

@@ -33,9 +33,17 @@ type Config struct {
 	DevRegistry Registry `yaml:"dev-registry" json:"dev-registry"`
 	// Cache options that are directly related to kaniko flags
 	Cache CacheConfig `yaml:"cache" json:"cache"`
-	// TagTemplate is go-template field that defines the format of the $_TAG substitution.
-	// See tags.Tag struct for more information and available fields
+	// TagTemplate is used to generate default tag for push events for current image-builder version.
+	// This will be removed after migration.
 	TagTemplate tags.Tag `yaml:"tag-template" json:"tag-template"`
+	// Default Tag template used for images build on commit.
+	// The value can be a go-template string or literal tag value string.
+	// See tags.Tag struct for more information and available fields
+	DefaultCommitTag tags.Tag `yaml:"default-commit-tag" json:"default-commit-tag"`
+	// Default Tag template used for images build on pull request.
+	// The value can be a go-template string or literal tag value string.
+	// See tags.Tag struct for more information and available fields
+	DefaultPRTag tags.Tag `yaml:"default-pr-tag" json:"default-pr-tag"`
 	// LogFormat defines the format kaniko logs are projected.
 	// Supported formats are 'color', 'text' and 'json'. Default: 'color'
 	LogFormat string `yaml:"log-format" json:"log-format"`

cmd/image-builder/config_test.go

@@ -19,11 +19,19 @@ func Test_ParseConfig(t *testing.T) {
 			name: "parsed full config one repo",
 			config: `registry: kyma-project.io/prod-registry
 dev-registry: dev.kyma-project.io/dev-registry
-tag-template: v{{ .Date }}-{{ .ShortSHA }}`,
+default-commit-tag:
+  name: default_tag
+  value: v{{ .Date }}-{{ .ShortSHA }}
+  validation: ^(v[0-9]{8}-[0-9a-f]{8})$
+default-pr-tag:
+  name: default_tag
+  value: pr-{{ .PRNumber }}
+  validation: ^(PR-[0-9]+)$`,
 			expectedConfig: Config{
-				Registry:    []string{"kyma-project.io/prod-registry"},
-				DevRegistry: []string{"dev.kyma-project.io/dev-registry"},
-				TagTemplate: tags.Tag{Name: "default_tag", Value: `v{{ .Date }}-{{ .ShortSHA }}`},
+				Registry:         []string{"kyma-project.io/prod-registry"},
+				DevRegistry:      []string{"dev.kyma-project.io/dev-registry"},
+				DefaultCommitTag: tags.Tag{Name: "default_tag", Value: `v{{ .Date }}-{{ .ShortSHA }}`, Validation: `^(v[0-9]{8}-[0-9a-f]{8})$`},
+				DefaultPRTag:     tags.Tag{Name: "default_tag", Value: `pr-{{ .PRNumber }}`, Validation: `^(PR-[0-9]+)$`},
 			},
 		},
 		{
@@ -34,11 +42,19 @@ tag-template: v{{ .Date }}-{{ .ShortSHA }}`,
 dev-registry:
 - dev.kyma-project.io/dev-registry
 - dev.kyma-project.io/second-registry
-tag-template: v{{ .Date }}-{{ .ShortSHA }}`,
+default-commit-tag:
+  name: default_tag
+  value: v{{ .Date }}-{{ .ShortSHA }}
+  validation: ^(v[0-9]{8}-[0-9a-f]{8})$
+default-pr-tag:
+  name: default_tag
+  value: pr-{{ .PRNumber }}
+  validation: ^(PR-[0-9]+)$`,
 			expectedConfig: Config{
-				Registry:    []string{"kyma-project.io/prod-registry", "kyma-project.io/second-registry"},
-				DevRegistry: []string{"dev.kyma-project.io/dev-registry", "dev.kyma-project.io/second-registry"},
-				TagTemplate: tags.Tag{Name: "default_tag", Value: `v{{ .Date }}-{{ .ShortSHA }}`},
+				Registry:         []string{"kyma-project.io/prod-registry", "kyma-project.io/second-registry"},
+				DevRegistry:      []string{"dev.kyma-project.io/dev-registry", "dev.kyma-project.io/second-registry"},
+				DefaultCommitTag: tags.Tag{Name: "default_tag", Value: `v{{ .Date }}-{{ .ShortSHA }}`, Validation: `^(v[0-9]{8}-[0-9a-f]{8})$`},
+				DefaultPRTag:     tags.Tag{Name: "default_tag", Value: `pr-{{ .PRNumber }}`, Validation: `^(PR-[0-9]+)$`},
 			},
 		},
 		{

cmd/image-builder/main.go

@@ -471,8 +471,13 @@ func buildLocally(o options) error {
 		return fmt.Errorf("'sha' could not be determined")
 	}
 
+	defaultTag, err := getDefaultTag(o)
+	if err != nil {
+		return err
+	}
+
 	// Get the tags for the image.
-	parsedTags, err := getTags(pr, sha, append(o.tags, o.TagTemplate))
+	parsedTags, err := getTags(pr, sha, append(o.tags, defaultTag))
 	if err != nil {
 		return err
 	}
@@ -638,13 +643,16 @@ func (l *StrList) List() []string {
 }
 
 func getTags(pr, sha string, templates []tags.Tag) ([]tags.Tag, error) {
-	// (Ressetkk): PR tag should not be hardcoded, in the future we have to find a way to parametrize it
-	if pr != "" {
-		// assume we are using PR number, build default tag as 'PR-XXXX'
-		return []tags.Tag{{Name: "default_tag", Value: "PR-" + pr}}, nil
+	var taggerOptions []tags.TagOption
+	if len(pr) > 0 {
+		taggerOptions = append(taggerOptions, tags.PRNumber(pr))
+	}
+	if len(sha) > 0 {
+		taggerOptions = append(taggerOptions, tags.CommitSHA(sha))
 	}
+
 	// build a tag from commit SHA
-	tagger, err := tags.NewTagger(templates, tags.CommitSHA(sha))
+	tagger, err := tags.NewTagger(templates, taggerOptions...)
 	if err != nil {
 		return nil, fmt.Errorf("get tagger: %w", err)
 	}
@@ -914,41 +922,59 @@ func getEnvs(o options, dockerfilePath string) (map[string]string, error) {
 }
 
 func parseTags(o options) ([]tags.Tag, error) {
-	var pr string
-	sha := o.gitState.BaseCommitSHA
-	if o.gitState.isPullRequest {
-		pr = fmt.Sprint(o.gitState.PullRequestNumber)
+	var (
+		pr  string
+		sha string
+	)
+	if !o.gitState.isPullRequest && o.gitState.BaseCommitSHA != "" {
+		sha = o.gitState.BaseCommitSHA
 	}
-
-	if sha == "" {
-		return nil, fmt.Errorf("sha still empty")
+	if o.gitState.isPullRequest && o.gitState.PullRequestNumber > 0 {
+		pr = fmt.Sprint(o.gitState.PullRequestNumber)
 	}
 
+	// TODO (dekiel): Tags provided as base64 encoded string should be parsed and added to the tags list when parsing flags.
+	//   This way all tags are available in the tags list from thr very beginning of execution and can be used in any process.
 	// read tags from base64 encoded string if provided
 	if o.tagsBase64 != "" {
 		decoded, err := base64.StdEncoding.DecodeString(o.tagsBase64)
 		if err != nil {
-			fmt.Printf("Failed to decode tags, error: %s", err)
-			os.Exit(1)
+			return nil, fmt.Errorf("failed to decode tags, error: %w", err)
 		}
 		splitedTags := strings.Split(string(decoded), ",")
 		for _, tag := range splitedTags {
 			err = o.tags.Set(tag)
 			if err != nil {
-				fmt.Printf("Failed to set tag, tag: %s, error: %s", tag, err)
-				os.Exit(1)
+				return nil, fmt.Errorf("failed to set tag, tag: %s, error: %w", tag, err)
 			}
 		}
 	}
 
-	parsedTags, err := getTags(pr, sha, append(o.tags, o.TagTemplate))
+	defaultTag, err := getDefaultTag(o)
+	if err != nil {
+		return nil, err
+	}
+	parsedTags, err := getTags(pr, sha, append(o.tags, defaultTag))
 	if err != nil {
 		return nil, err
 	}
 
 	return parsedTags, nil
 }
 
+// getDefaultTag returns the default tag based on the read git state.
+// The function provid default tag for pull request or commit.
+// The default tag is read from the provided options struct.
+func getDefaultTag(o options) (tags.Tag, error) {
+	if o.gitState.isPullRequest && o.gitState.PullRequestNumber > 0 {
+		return o.DefaultPRTag, nil
+	}
+	if len(o.gitState.BaseCommitSHA) > 0 {
+		return o.DefaultCommitTag, nil
+	}
+	return tags.Tag{}, fmt.Errorf("could not determine default tag, no pr number or commit sha provided")
+}
+
 func getDockerfileDirPath(o options) (string, error) {
 	// Get the absolute path to the build context directory.
 	context, err := filepath.Abs(o.context)