simplify nobuild/force/build logic

Signed-off-by: Avi Deitcher <avi@deitcher.net>

src/cmd/linuxkit/pkg_build.go

@@ -33,24 +33,31 @@ func pkgBuildPush(args []string, withPush bool) {
 		flags.PrintDefaults()
 	}
 
-	force := flags.Bool("force", false, "Force rebuild")
+	force := flags.Bool("force", false, "Force rebuild even if image is in local cache")
 	docker := flags.Bool("docker", false, "Store the built image in the docker image cache instead of the default linuxkit cache")
 	platforms := flags.String("platforms", "", "Which platforms to build for, defaults to all of those for which the package can be built")
 	skipPlatforms := flags.String("skip-platforms", "", "Platforms that should be skipped, even if present in build.yml")
 	builders := flags.String("builders", "", "Which builders to use for which platforms, e.g. linux/arm64=docker-context-arm64, overrides defaults and environment variables, see https://github.com/linuxkit/linuxkit/blob/master/docs/packages.md#Providing-native-builder-nodes")
 	buildCacheDir := flags.String("cache", defaultLinuxkitCache(), "Directory for storing built image, incompatible with --docker")
 
+	// some logic clarification:
+	// pkg build                   - always builds unless is in cache
+	// pkg build --force           - always builds even if is in cache
+	// pkg push                    - always builds unless is in cache
+	// pkg push --force            - always builds even if is in cache
+	// pkg push --nobuild          - skips build; if not in cache, fails
+	// pkg push --nobuild --force  - nonsensical
+
 	var (
-		release                  *string
+		release           *string
-		nobuild, manifest, image *bool
+		nobuild, manifest *bool
-		imageRef                 = false
+		nobuildRef        = false
 	)
-	image = &imageRef
+	nobuild = &nobuildRef
 	if withPush {
 		release = flags.String("release", "", "Release the given version")
-		nobuild = flags.Bool("nobuild", false, "Skip the build")
+		nobuild = flags.Bool("nobuild", false, "Skip building the image before pushing, conflicts with -force")
 		manifest = flags.Bool("manifest", true, "Create and push multi-arch manifest")
-		image = flags.Bool("image", true, "Build and push image for the current platform")
 	}
 
 	pkgs, err := pkglib.NewFromCLI(flags, args...)
@@ -59,10 +66,12 @@ func pkgBuildPush(args []string, withPush bool) {
 		os.Exit(1)
 	}
 
-	var opts []pkglib.BuildOpt
+	if *nobuild && *force {
-	if *image {
+		fmt.Fprint(os.Stderr, "flags -force and -nobuild conflict")
-		opts = append(opts, pkglib.WithBuildImage())
+		os.Exit(1)
 	}
+
+	var opts []pkglib.BuildOpt
 	if *force {
 		opts = append(opts, pkglib.WithBuildForce())
 	}

src/cmd/linuxkit/pkglib/build.go

@@ -68,14 +68,6 @@ func WithBuildPush() BuildOpt {
 	}
 }
 
-// WithBuildImage builds the image
-func WithBuildImage() BuildOpt {
-	return func(bo *buildOpts) error {
-		bo.image = true
-		return nil
-	}
-}
-
 // WithBuildManifest creates a multi-arch manifest for the image
 func WithBuildManifest() BuildOpt {
 	return func(bo *buildOpts) error {
@@ -231,7 +223,7 @@ func (p Pkg) Build(bos ...BuildOpt) error {
 		}
 	}
 
-	if bo.image && !skipBuild {
+	if !skipBuild {
 		fmt.Fprintf(writer, "building %s\n", ref)
 		var (
 			args  []string

src/cmd/linuxkit/pkglib/build_test.go

@@ -303,9 +303,9 @@ func TestBuild(t *testing.T) {
 		{"no build cache", Pkg{org: "foo", image: "bar", hash: "abc", arches: []string{"amd64"}, commitHash: "HEAD"}, nil, []string{"amd64"}, &dockerMocker{supportBuildKit: false}, &cacheMocker{}, "must provide linuxkit build cache"},
 		{"unsupported buildkit", Pkg{org: "foo", image: "bar", hash: "abc", arches: []string{"amd64"}, commitHash: "HEAD"}, []BuildOpt{WithBuildCacheDir(cacheDir)}, []string{"amd64"}, &dockerMocker{supportBuildKit: false}, &cacheMocker{}, "buildkit not supported, check docker version"},
 		{"load docker without local platform", Pkg{org: "foo", image: "bar", hash: "abc", arches: []string{"amd64", "arm64"}, commitHash: "HEAD"}, []BuildOpt{WithBuildCacheDir(cacheDir), WithBuildTargetDockerCache()}, []string{nonLocal}, &dockerMocker{supportBuildKit: false}, &cacheMocker{}, "must build for local platform"},
-		{"amd64", Pkg{org: "foo", image: "bar", hash: "abc", arches: []string{"amd64", "arm64"}, commitHash: "HEAD"}, []BuildOpt{WithBuildCacheDir(cacheDir), WithBuildImage()}, []string{"amd64"}, &dockerMocker{supportBuildKit: true, enableBuild: true}, &cacheMocker{enableImagePull: false, enableImageLoad: true, enableIndexWrite: true}, ""},
+		{"amd64", Pkg{org: "foo", image: "bar", hash: "abc", arches: []string{"amd64", "arm64"}, commitHash: "HEAD"}, []BuildOpt{WithBuildCacheDir(cacheDir)}, []string{"amd64"}, &dockerMocker{supportBuildKit: true, enableBuild: true}, &cacheMocker{enableImagePull: false, enableImageLoad: true, enableIndexWrite: true}, ""},
-		{"arm64", Pkg{org: "foo", image: "bar", hash: "abc", arches: []string{"amd64", "arm64"}, commitHash: "HEAD"}, []BuildOpt{WithBuildCacheDir(cacheDir), WithBuildImage()}, []string{"arm64"}, &dockerMocker{supportBuildKit: true, enableBuild: true}, &cacheMocker{enableImagePull: false, enableImageLoad: true, enableIndexWrite: true}, ""},
+		{"arm64", Pkg{org: "foo", image: "bar", hash: "abc", arches: []string{"amd64", "arm64"}, commitHash: "HEAD"}, []BuildOpt{WithBuildCacheDir(cacheDir)}, []string{"arm64"}, &dockerMocker{supportBuildKit: true, enableBuild: true}, &cacheMocker{enableImagePull: false, enableImageLoad: true, enableIndexWrite: true}, ""},
-		{"amd64 and arm64", Pkg{org: "foo", image: "bar", hash: "abc", arches: []string{"amd64", "arm64"}, commitHash: "HEAD"}, []BuildOpt{WithBuildCacheDir(cacheDir), WithBuildImage()}, []string{"amd64", "arm64"}, &dockerMocker{supportBuildKit: true, enableBuild: true}, &cacheMocker{enableImagePull: false, enableImageLoad: true, enableIndexWrite: true}, ""},
+		{"amd64 and arm64", Pkg{org: "foo", image: "bar", hash: "abc", arches: []string{"amd64", "arm64"}, commitHash: "HEAD"}, []BuildOpt{WithBuildCacheDir(cacheDir)}, []string{"amd64", "arm64"}, &dockerMocker{supportBuildKit: true, enableBuild: true}, &cacheMocker{enableImagePull: false, enableImageLoad: true, enableIndexWrite: true}, ""},
 	}
 	for _, tt := range tests {
 		t.Run(tt.msg, func(t *testing.T) {