Fix #3344

Signed-off-by: David Gageot <[email protected]>

Author: dgageot

pkg/skaffold/build/tag/git_commit.go

@@ -21,6 +21,7 @@ import (
 	"fmt"
 	"os/exec"
 	"path/filepath"
+	"regexp"
 	"strings"
 
 	"github.com/pkg/errors"
@@ -89,7 +90,29 @@ func (c *GitCommit) GenerateFullyQualifiedImageName(workingDir string, imageName
 		return fmt.Sprintf("%s:%s-dirty", imageName, ref), nil
 	}
 
-	return fmt.Sprintf("%s:%s", imageName, ref), nil
+	return fmt.Sprintf("%s:%s", imageName, sanitizeTag(ref)), nil
+}
+
+// sanitizeTag takes a git tag and converts it to a docker tag by removing
+// all the characters that are not allowed by docker.
+func sanitizeTag(tag string) string {
+	// Replace unsupported characters with `_`
+	sanitized := regexp.MustCompile(`[^a-zA-Z0-9-._]`).ReplaceAllString(tag, `_`)
+
+	// Remove leading `-`s and `.`s
+	prefixSuffix := regexp.MustCompile(`([-.]*)(.*)`).FindStringSubmatch(sanitized)
+	sanitized = strings.Repeat("_", len(prefixSuffix[1])) + prefixSuffix[2]
+
+	// Truncate to 128 characters
+	if len(sanitized) > 128 {
+		return sanitized[0:128]
+	}
+
+	if tag != sanitized {
+		logrus.Warnf("Using %q instead of %q as an image tag", sanitized, tag)
+	}
+
+	return sanitized
 }
 
 func (c *GitCommit) makeGitTag(workingDir string) (string, error) {

pkg/skaffold/build/tag/git_commit_test.go

@@ -22,6 +22,7 @@ import (
 	"io/ioutil"
 	"os"
 	"path/filepath"
+	"strings"
 	"testing"
 	"time"
 
@@ -59,6 +60,25 @@ func TestGitCommit_GenerateFullyQualifiedImageName(t *testing.T) {
 					commit("initial")
 			},
 		},
+		{
+			description:            "clean worktree with tag containing a slash",
+			variantTags:            "test:v_2",
+			variantCommitSha:       "test:aea33bcc86b5af8c8570ff45d8a643202d63c808",
+			variantAbbrevCommitSha: "test:aea33bc",
+			variantTreeSha:         "test:bc69d50cda6897a6f2054e64b9059f038dc6fb0e",
+			variantAbbrevTreeSha:   "test:bc69d50",
+			createGitRepo: func(dir string) {
+				gitInit(t, dir).
+					write("source.go", "code").
+					add("source.go").
+					commit("initial").
+					tag("v/1").
+					write("other.go", "other").
+					add("other.go").
+					commit("second commit").
+					tag("v/2")
+			},
+		},
 		{
 			description:            "clean worktree with tags",
 			variantTags:            "test:v2",
@@ -341,6 +361,23 @@ func TestGitCommit_GenerateFullyQualifiedImageName(t *testing.T) {
 	}
 }
 
+func TestSanitizeTag(t *testing.T) {
+	testutil.Run(t, "valid tags", func(t *testutil.T) {
+		t.CheckDeepEqual("abcdefghijklmnopqrstuvwxyz", sanitizeTag("abcdefghijklmnopqrstuvwxyz"))
+		t.CheckDeepEqual("ABCDEFGHIJKLMNOPQRSTUVWXYZ", sanitizeTag("ABCDEFGHIJKLMNOPQRSTUVWXYZ"))
+		t.CheckDeepEqual("0123456789-_.", sanitizeTag("0123456789-_."))
+		t.CheckDeepEqual("_v1", sanitizeTag("_v1"))
+	})
+
+	testutil.Run(t, "sanitized tags", func(t *testutil.T) {
+		t.CheckDeepEqual("v_1", sanitizeTag("v/1"))
+		t.CheckDeepEqual("v____1", sanitizeTag("v%$@!1"))
+		t.CheckDeepEqual("__v1", sanitizeTag("--v1"))
+		t.CheckDeepEqual("__v1", sanitizeTag("..v1"))
+		t.CheckDeepEqual(128, len(sanitizeTag(strings.Repeat("0123456789", 20))))
+	})
+}
+
 // gitRepo deals with test git repositories
 type gitRepo struct {
 	dir      string