Add configurable tag for use with auto_tag (#36)

Implements #30, allows setting a (single) tag to override the default of `latest` allows for the woodpecker-ci usecase of setting `next` as the tag for the default branch.

Co-authored-by: Gapodo <gapodo@datenclown.at>
Reviewed-on: https://codeberg.org/woodpecker-plugins/plugin-docker-buildx/pulls/36
Reviewed-by: 6543 <6543@obermui.de>
Co-authored-by: gapodo <gapodo@geekvoid.net>
Co-committed-by: gapodo <gapodo@geekvoid.net>

cmd/docker-buildx/config.go

@@ -127,6 +127,13 @@ func settingsFlags(settings *plugin.Settings) []cli.Flag {
 			Usage:       "generates tag names automatically based on git branch and git tag",
 			Destination: &settings.Build.TagsAuto,
 		},
+		&cli.StringFlag{
+			Name:        "tags.defaultName",
+			EnvVars:     []string{"PLUGIN_DEFAULT_TAG"},
+			Usage:       "allows setting an alternative to `latest` for the auto tag",
+			Destination: &settings.Build.TagsDefaultName,
+			Value:       "latest",
+		},
 		&cli.StringFlag{
 			Name:        "tags.suffix",
 			EnvVars:     []string{"PLUGIN_DEFAULT_SUFFIX", "PLUGIN_AUTO_TAG_SUFFIX"},

docs.md

@@ -99,6 +99,7 @@ It will automatically generate buildkit configuration to use custom CA certifica
 | `context`                 | `.`               | sets the path of the build context to use
 | `default_tags`/`auto_tag` | `false`           | generates tag names automatically based on git branch and git tag, tags supplied via `tags` are additionally added to the auto_tags without suffix
 | `default_suffix"`/`auto_tag_suffix`| *none*   | generates tag names with the given suffix
+| `default_tag`             | `latest`          | overrides the default tag name used when generating with `auto_tag` enabled
 | `label`/`labels`          | *none*            | sets labels to use for the image in format `<name>=<value>`
 | `default_labels`/`auto_labels` | `true`       | sets docker image labels based on git information
 | `build_args`              | *none*            | sets custom build arguments for the build

plugin/impl.go

@@ -43,28 +43,29 @@ type Login struct {
 
 // Build defines Docker build parameters.
 type Build struct {
-	Remote     string          // Git remote URL
-	Ref        string          // Git commit ref
-	Branch     string          // Git repository branch
-	Dockerfile string          // Docker build Dockerfile
-	Context    string          // Docker build context
-	TagsAuto   bool            // Docker build auto tag
-	TagsSuffix string          // Docker build tags with suffix
-	Tags       cli.StringSlice // Docker build tags
-	LabelsAuto bool            // Docker build auto labels
-	Labels     cli.StringSlice // Docker build labels
-	Platforms  cli.StringSlice // Docker build target platforms
-	Args       cli.StringSlice // Docker build args
-	ArgsEnv    cli.StringSlice // Docker build args from env
-	Target     string          // Docker build target
-	Output     string          // Docker build output
-	Pull       bool            // Docker build pull
-	CacheFrom  cli.StringSlice // Docker build cache-from
-	Compress   bool            // Docker build compress
-	Repo       cli.StringSlice // Docker build repository
-	NoCache    bool            // Docker build no-cache
-	AddHost    cli.StringSlice // Docker build add-host
-	Quiet      bool            // Docker build quiet
+	Remote          string          // Git remote URL
+	Ref             string          // Git commit ref
+	Branch          string          // Git repository branch
+	Dockerfile      string          // Docker build Dockerfile
+	Context         string          // Docker build context
+	TagsAuto        bool            // Docker build auto tag
+	TagsDefaultName string          // Docker build auto tag name override
+	TagsSuffix      string          // Docker build tags with suffix
+	Tags            cli.StringSlice // Docker build tags
+	LabelsAuto      bool            // Docker build auto labels
+	Labels          cli.StringSlice // Docker build labels
+	Platforms       cli.StringSlice // Docker build target platforms
+	Args            cli.StringSlice // Docker build args
+	ArgsEnv         cli.StringSlice // Docker build args from env
+	Target          string          // Docker build target
+	Output          string          // Docker build output
+	Pull            bool            // Docker build pull
+	CacheFrom       cli.StringSlice // Docker build cache-from
+	Compress        bool            // Docker build compress
+	Repo            cli.StringSlice // Docker build repository
+	NoCache         bool            // Docker build no-cache
+	AddHost         cli.StringSlice // Docker build add-host
+	Quiet           bool            // Docker build quiet
 }
 
 // Settings for the Plugin.
@@ -110,6 +111,10 @@ func (p *Plugin) Validate() error {
 		return err
 	}
 
+	if !isSingleTag(p.settings.Build.TagsDefaultName) {
+		return fmt.Errorf("'%s' is not a valid, single tag", p.settings.Build.TagsDefaultName)
+	}
+
 	// beside the default login all other logins need to set a username and password
 	for _, l := range p.settings.Logins[1:] {
 		if l.anonymous() {
@@ -126,6 +131,7 @@ func (p *Plugin) Validate() error {
 			tag, err := DefaultTagSuffix(
 				p.settings.Build.Ref,
 				p.settings.Build.TagsSuffix,
+				p.settings.Build.TagsDefaultName,
 			)
 			if err != nil {
 				logrus.Printf("cannot build docker image for %s, invalid semantic version", p.settings.Build.Ref)

plugin/impl_test.go

@@ -13,10 +13,11 @@ var defaultSettings = Settings{
 		StoragePath: "/var/lib/docker",
 	},
 	Build: Build{
-		Context:    ".",
-		Tags:       *cli.NewStringSlice("latest"),
-		LabelsAuto: true,
-		Pull:       true,
+		Context:         ".",
+		Tags:            *cli.NewStringSlice("latest"),
+		TagsDefaultName: "latest",
+		LabelsAuto:      true,
+		Pull:            true,
 	},
 	DefaultLogin: Login{
 		Registry: "https://index.docker.io/v1/",

plugin/tags.go

@@ -2,6 +2,7 @@ package plugin
 
 import (
 	"fmt"
+	"regexp"
 	"strings"
 
 	"github.com/coreos/go-semver/semver"
@@ -9,8 +10,8 @@ import (
 
 // DefaultTagSuffix returns a set of default suggested tags
 // based on the commit ref with an attached suffix.
-func DefaultTagSuffix(ref, suffix string) ([]string, error) {
-	tags, err := DefaultTags(ref)
+func DefaultTagSuffix(ref, defaultTag, suffix string) ([]string, error) {
+	tags, err := DefaultTags(ref, defaultTag)
 	if err != nil {
 		return nil, err
 	}
@@ -18,7 +19,7 @@ func DefaultTagSuffix(ref, suffix string) ([]string, error) {
 		return tags, nil
 	}
 	for i, tag := range tags {
-		if tag == "latest" {
+		if tag == defaultTag {
 			tags[i] = suffix
 		} else {
 			tags[i] = fmt.Sprintf("%s-%s", tag, suffix)
@@ -39,14 +40,14 @@ func splitOff(input, delim string) string {
 
 // DefaultTags returns a set of default suggested tags based on
 // the commit ref.
-func DefaultTags(ref string) ([]string, error) {
+func DefaultTags(ref, defaultTag string) ([]string, error) {
 	if !strings.HasPrefix(ref, "refs/tags/") {
-		return []string{"latest"}, nil
+		return []string{defaultTag}, nil
 	}
 	v := stripTagPrefix(ref)
 	version, err := semver.NewVersion(v)
 	if err != nil {
-		return []string{"latest"}, err
+		return []string{defaultTag}, err
 	}
 	if version.PreRelease != "" || version.Metadata != "" {
 		return []string{
@@ -91,3 +92,8 @@ func stripTagPrefix(ref string) string {
 	ref = strings.TrimPrefix(ref, "v")
 	return ref
 }
+
+func isSingleTag(tag string) bool {
+	// currently only filtering for seperators, this could be improoved...
+	return !regexp.MustCompile(`[,\s]+`).MatchString(tag) && len(tag) > 0 && len(tag) <= 128
+}

plugin/tags_test.go

@@ -25,19 +25,20 @@ func Test_stripTagPrefix(t *testing.T) {
 
 func TestDefaultTags(t *testing.T) {
 	tests := []struct {
-		Before string
-		After  []string
+		DefaultTag string
+		Before     string
+		After      []string
 	}{
-		{"", []string{"latest"}},
-		{"refs/heads/master", []string{"latest"}},
-		{"refs/tags/0.9.0", []string{"0.9", "0.9.0"}},
-		{"refs/tags/1.0.0", []string{"1", "1.0", "1.0.0"}},
-		{"refs/tags/v1.0.0", []string{"1", "1.0", "1.0.0"}},
-		{"refs/tags/v1.0.0-alpha.1", []string{"1.0.0-alpha.1"}},
+		{"latest", "", []string{"latest"}},
+		{"latest", "refs/heads/master", []string{"latest"}},
+		{"latest", "refs/tags/0.9.0", []string{"0.9", "0.9.0"}},
+		{"latest", "refs/tags/1.0.0", []string{"1", "1.0", "1.0.0"}},
+		{"latest", "refs/tags/v1.0.0", []string{"1", "1.0", "1.0.0"}},
+		{"latest", "refs/tags/v1.0.0-alpha.1", []string{"1.0.0-alpha.1"}},
 	}
 
 	for _, test := range tests {
-		tags, err := DefaultTags(test.Before)
+		tags, err := DefaultTags(test.Before, test.DefaultTag)
 		if err != nil {
 			t.Error(err)
 			continue
@@ -50,13 +51,22 @@ func TestDefaultTags(t *testing.T) {
 }
 
 func TestDefaultTagsError(t *testing.T) {
-	tests := []string{
-		"refs/tags/x1.0.0",
-		"refs/tags/20190203",
+	tests := []struct {
+		DefaultTag string
+		Before     string
+	}{
+		{
+			DefaultTag: "latest",
+			Before:     "refs/tags/x1.0.0",
+		},
+		{
+			DefaultTag: "latest",
+			Before:     "refs/tags/20190203",
+		},
 	}
 
 	for _, test := range tests {
-		_, err := DefaultTags(test)
+		_, err := DefaultTags(test.Before, test.DefaultTag)
 		if err == nil {
 			t.Errorf("Expect tag error for %s", test)
 		}
@@ -65,30 +75,59 @@ func TestDefaultTagsError(t *testing.T) {
 
 func TestDefaultTagSuffix(t *testing.T) {
 	tests := []struct {
-		Before string
-		Suffix string
-		After  []string
+		Name       string
+		Before     string
+		Suffix     string
+		After      []string
+		DefaultTag string
 	}{
-		// without suffix
 		{
-			After: []string{"latest"},
+			Name:       "Default tag without suffix",
+			DefaultTag: "latest",
+			After:      []string{"latest"},
 		},
 		{
-			Before: "refs/tags/v1.0.0",
+			Name:       "Overridden default tag without suffix",
+			DefaultTag: "next",
+			After:      []string{"next"},
+		},
+		{
+			Name:       "Generate version",
+			DefaultTag: "latest",
+			Before:     "refs/tags/v1.0.0",
 			After: []string{
 				"1",
 				"1.0",
 				"1.0.0",
 			},
 		},
-		// with suffix
 		{
-			Suffix: "linux-amd64",
-			After:  []string{"linux-amd64"},
+			Name:       "Generate version with overridden default tag",
+			DefaultTag: "next",
+			Before:     "refs/tags/v1.0.0",
+			After: []string{
+				"1",
+				"1.0",
+				"1.0.0",
+			},
 		},
 		{
-			Before: "refs/tags/v1.0.0",
-			Suffix: "linux-amd64",
+			Name:       "Default tag with suffix (linux-amd64)",
+			DefaultTag: "latest",
+			Suffix:     "linux-amd64",
+			After:      []string{"linux-amd64"},
+		},
+		{
+			Name:       "Overridden default tag with suffix (linux-amd64)",
+			DefaultTag: "next",
+			Suffix:     "linux-amd64",
+			After:      []string{"linux-amd64"},
+		},
+		{
+			Name:       "Generate version with suffix (linux-amd64)",
+			DefaultTag: "latest",
+			Before:     "refs/tags/v1.0.0",
+			Suffix:     "linux-amd64",
 			After: []string{
 				"1-linux-amd64",
 				"1.0-linux-amd64",
@@ -96,12 +135,33 @@ func TestDefaultTagSuffix(t *testing.T) {
 			},
 		},
 		{
-			Suffix: "nanoserver",
-			After:  []string{"nanoserver"},
+			Name:       "Generate version with suffix (linux-amd64) and overridden default tag (next)",
+			DefaultTag: "next",
+			Before:     "refs/tags/v1.0.0",
+			Suffix:     "linux-amd64",
+			After: []string{
+				"1-linux-amd64",
+				"1.0-linux-amd64",
+				"1.0.0-linux-amd64",
+			},
 		},
 		{
-			Before: "refs/tags/v1.9.2",
-			Suffix: "nanoserver",
+			Name:       "Default tag with suffix (nanoserver)",
+			DefaultTag: "latest",
+			Suffix:     "nanoserver",
+			After:      []string{"nanoserver"},
+		},
+		{
+			Name:       "Overridden default tag with suffix (nanoserver)",
+			DefaultTag: "next",
+			Suffix:     "nanoserver",
+			After:      []string{"nanoserver"},
+		},
+		{
+			Name:       "Generate version with suffix (nanoserver)",
+			DefaultTag: "latest",
+			Before:     "refs/tags/v1.9.2",
+			Suffix:     "nanoserver",
 			After: []string{
 				"1-nanoserver",
 				"1.9-nanoserver",
@@ -109,8 +169,32 @@ func TestDefaultTagSuffix(t *testing.T) {
 			},
 		},
 		{
-			Before: "refs/tags/v18.06.0",
-			Suffix: "nanoserver",
+			Name:       "Generate version with suffix (nanoserver) and overridden default tag (next)",
+			DefaultTag: "latest",
+			Before:     "refs/tags/v1.9.2",
+			Suffix:     "nanoserver",
+			After: []string{
+				"1-nanoserver",
+				"1.9-nanoserver",
+				"1.9.2-nanoserver",
+			},
+		},
+		{
+			Name:       "Generate version with suffix (zero-padded version)",
+			DefaultTag: "latest",
+			Before:     "refs/tags/v18.06.0",
+			Suffix:     "nanoserver",
+			After: []string{
+				"18-nanoserver",
+				"18.06-nanoserver",
+				"18.06.0-nanoserver",
+			},
+		},
+		{
+			Name:       "Generate version with suffix (zero-padded version) with overridden default tag (next)",
+			DefaultTag: "next",
+			Before:     "refs/tags/v18.06.0",
+			Suffix:     "nanoserver",
 			After: []string{
 				"18-nanoserver",
 				"18.06-nanoserver",
@@ -120,14 +204,14 @@ func TestDefaultTagSuffix(t *testing.T) {
 	}
 
 	for _, test := range tests {
-		tag, err := DefaultTagSuffix(test.Before, test.Suffix)
+		tag, err := DefaultTagSuffix(test.Before, test.DefaultTag, test.Suffix)
 		if err != nil {
 			t.Error(err)
 			continue
 		}
 		got, want := tag, test.After
 		if !reflect.DeepEqual(got, want) {
-			t.Errorf("Got tag %v, want %v", got, want)
+			t.Errorf("%q. Got tag %v, want %v", test.Name, got, want)
 		}
 	}
 }
@@ -195,3 +279,26 @@ func TestUseDefaultTag(t *testing.T) {
 		}
 	}
 }
+
+func Test_isSingleTag(t *testing.T) {
+	tests := []struct {
+		Tag     string
+		IsValid bool
+	}{
+		{"latest", true},
+		{" latest", false},
+		{"LaTest__Hi", true},
+		{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ__.-0123456789", true},
+		{"_wierd.but-ok1", true},
+		{"latest ", false},
+		{"latest,next", false},
+		// more tests to be added, once the validation is more powerful
+	}
+
+	for _, test := range tests {
+		valid := isSingleTag(test.Tag)
+		if valid != test.IsValid {
+			t.Errorf("Tag verification '%s' tag %v, want %v", test.Tag, valid, test.IsValid)
+		}
+	}
+}