Replace go-bindata with go:embed

Use Go's built-in way of embedding static assets in binaries, instead
of relying on the somewhat legacy go-bindata tool. This allows the
embedding to be handled transparently by the Go compiler, eliminating
some extra Makefile steps.

Hide the path prefixes used to embed the data behind a sub-fs.

Signed-off-by: Tom Wieczorek <twieczorek@mirantis.com>

.gitignore

@@ -17,7 +17,6 @@
 aws_private.pem
 out.json
 .vscode
-static/zz_generated_assets.go
 .k0sbuild.docker-image.*
 docs/cli
 site

Makefile

@@ -165,16 +165,6 @@ pkg/client/clientset/.client-gen.stamp: .k0sbuild.docker-image.k0s hack/tools/bo
 	  && mv -f -- "$$gendir/out/clientset" pkg/client/.
 	touch -- '$@'
 
-codegen_targets += static/zz_generated_assets.go
-static/zz_generated_assets.go: $(controller_gen_targets) # to generate the CRDs into static/_crds/*
-static/zz_generated_assets.go: $(shell find static/manifests/calico static/manifests/windows -type f)
-static/zz_generated_assets.go: .k0sbuild.docker-image.k0s hack/tools/Makefile.variables
-	CGO_ENABLED=0 $(GO) run github.com/kevinburke/go-bindata/go-bindata@v$(go-bindata_version) \
-	  -o '$@' -pkg static -prefix static \
-	  $(foreach gv,$(api_group_versions),static/_crds/$(dir $(gv))...) \
-	  static/manifests/calico/... \
-	  static/manifests/windows/...
-
 ifeq ($(EMBEDDED_BINS_BUILDMODE),none)
 BUILD_GO_TAGS += noembedbins
 else
@@ -195,7 +185,7 @@ k0s: .k0sbuild.docker-image.k0s
 k0s.exe: TARGET_OS = windows
 k0s.exe: BUILD_GO_CGO_ENABLED = 0
 
-k0s.exe k0s: go.sum $(codegen_targets) $(GO_SRCS) pkg/autopilot/checks/removed-gvks.yaml
+k0s.exe k0s: go.sum $(codegen_targets) $(GO_SRCS) pkg/autopilot/checks/removed-gvks.yaml $(shell find static/_crds static/manifests/calico static/manifests/windows -type f)
 	rm -f -- '$@'
 	CGO_ENABLED=$(BUILD_GO_CGO_ENABLED) CGO_CFLAGS='$(BUILD_CGO_CFLAGS)' GOOS=$(TARGET_OS) $(GO) build $(BUILD_GO_FLAGS) -ldflags='$(LD_FLAGS)' -o '$@' main.go
 ifneq ($(EMBEDDED_BINS_BUILDMODE),none)
@@ -214,7 +204,7 @@ codegen: $(codegen_targets)
 
 # bindata contains the parts of codegen which aren't version controlled.
 .PHONY: bindata
-bindata: static/zz_generated_assets.go
+bindata:
 ifneq ($(EMBEDDED_BINS_BUILDMODE),none)
 bindata: pkg/assets/zz_generated_offsets_$(TARGET_OS).go
 endif
@@ -287,7 +277,7 @@ clean-airgap-image-bundles:
 
 .PHONY: clean
 clean: clean-gocache clean-docker-image clean-airgap-image-bundles
-	-rm -f pkg/assets/zz_generated_offsets_*.go k0s k0s.exe .bins.*stamp bindata* static/zz_generated_assets.go
+	-rm -f pkg/assets/zz_generated_offsets_*.go k0s k0s.exe .bins.*stamp bindata*
 	-rm -rf $(K0S_GO_BUILD_CACHE)
 	-find pkg/apis -type f -name .controller-gen.stamp -delete
 	-rm pkg/client/clientset/.client-gen.stamp

embedded-bins/kubernetes/Dockerfile

@@ -2,7 +2,7 @@ ARG BUILDIMAGE
 FROM $BUILDIMAGE AS build
 
 ARG VERSION
-RUN apk add build-base git go-bindata linux-headers rsync grep coreutils bash
+RUN apk add build-base git linux-headers rsync grep coreutils bash
 
 RUN mkdir -p $GOPATH/src/github.com/kubernetes/kubernetes
 RUN git -c advice.detachedHead=false clone -b v$VERSION --depth=1 https://github.com/kubernetes/kubernetes.git $GOPATH/src/github.com/kubernetes/kubernetes

hack/tools/Makefile.variables

@@ -1,3 +1,2 @@
 controller-gen_version = 0.15.0
-go-bindata_version = 3.23.0+incompatible
 golangci-lint_version = 1.57.1

pkg/component/controller/calico.go

@@ -20,6 +20,8 @@ import (
 	"bytes"
 	"context"
 	"fmt"
+	"io/fs"
+	"path"
 	"path/filepath"
 	"reflect"
 	"strings"
@@ -104,17 +106,18 @@ func (c *Calico) dumpCRDs() error {
 	var emptyStruct struct{}
 
 	// Write the CRD definitions only at "boot", they do not change during runtime
-	crds, err := static.AssetDir("manifests/calico/CustomResourceDefinition")
+	crds, err := fs.ReadDir(static.CalicoManifests, "CustomResourceDefinition")
 	if err != nil {
 		return err
 	}
 
-	for _, filename := range crds {
+	for _, entry := range crds {
+		filename := entry.Name()
 		manifestName := fmt.Sprintf("calico-crd-%s", filename)
 
 		output := bytes.NewBuffer([]byte{})
 
-		contents, err := static.Asset(fmt.Sprintf("manifests/calico/CustomResourceDefinition/%s", filename))
+		contents, err := fs.ReadFile(static.CalicoManifests, path.Join("CustomResourceDefinition", filename))
 		if err != nil {
 			return fmt.Errorf("failed to fetch crd %s: %w", filename, err)
 		}
@@ -137,17 +140,18 @@ func (c *Calico) dumpCRDs() error {
 }
 
 func (c *Calico) processConfigChanges(newConfig calicoConfig) error {
-	manifestDirectories, err := static.AssetDir("manifests/calico")
+	manifestDirectories, err := fs.ReadDir(static.CalicoManifests, ".")
 	if err != nil {
 		return fmt.Errorf("error retrieving calico manifests: %w, will retry", err)
 	}
 
-	for _, dir := range manifestDirectories {
+	for _, entry := range manifestDirectories {
+		dir := entry.Name()
 		// CRDs are handled separately on boot
 		if dir == "CustomResourceDefinition" {
 			continue
 		}
-		manifestPaths, err := static.AssetDir(fmt.Sprintf("manifests/calico/%s", dir))
+		manifestPaths, err := fs.ReadDir(static.CalicoManifests, dir)
 		if err != nil {
 			return fmt.Errorf("error retrieving calico manifests: %w, will retry", err)
 		}
@@ -158,10 +162,11 @@ func (c *Calico) processConfigChanges(newConfig calicoConfig) error {
 			}
 		}
 
-		for _, filename := range manifestPaths {
+		for _, entry := range manifestPaths {
+			filename := entry.Name()
 			manifestName := fmt.Sprintf("calico-%s-%s", dir, filename)
 			output := bytes.NewBuffer([]byte{})
-			contents, err := static.Asset(fmt.Sprintf("manifests/calico/%s/%s", dir, filename))
+			contents, err := fs.ReadFile(static.CalicoManifests, path.Join(dir, filename))
 			if err != nil {
 				return fmt.Errorf("can't find manifest %s: %w", manifestName, err)
 			}

pkg/component/controller/calico_test.go

@@ -61,7 +61,7 @@ func TestCalicoManifests(t *testing.T) {
 		calico := NewCalico(k0sVars, crdSaver, saver)
 		cfg, err := calico.getConfig(clusterConfig)
 		require.NoError(t, err)
-		_ = calico.processConfigChanges(cfg)
+		require.NoError(t, calico.processConfigChanges(cfg))
 
 		daemonSetManifestRaw, foundRaw := saver["calico-DaemonSet-calico-node.yaml"]
 		require.True(t, foundRaw, "must have daemon set for calico")

pkg/component/controller/crd.go

@@ -19,6 +19,7 @@ package controller
 import (
 	"context"
 	"fmt"
+	"io/fs"
 	"path"
 
 	"github.com/k0sproject/k0s/pkg/component/manager"
@@ -69,16 +70,16 @@ func (c CRD) Init(_ context.Context) error {
 }
 
 // Run unpacks manifests from bindata
-func (c CRD) Start(_ context.Context) error {
-	crdAssetsPath := path.Join("_crds", c.assetsDir)
-	crds, err := static.AssetDir(crdAssetsPath)
+func (c CRD) Start(context.Context) error {
+	crds, err := fs.ReadDir(static.CRDs, c.assetsDir)
 	if err != nil {
 		return fmt.Errorf("can't unbundle CRD `%s` manifests: %w", c.bundle, err)
 	}
 
-	for _, filename := range crds {
+	for _, entry := range crds {
+		filename := entry.Name()
 		manifestName := fmt.Sprintf("%s-crd-%s", c.bundle, filename)
-		content, err := static.Asset(path.Join(crdAssetsPath, filename))
+		content, err := fs.ReadFile(static.CRDs, path.Join(c.assetsDir, filename))
 		if err != nil {
 			return fmt.Errorf("failed to fetch crd `%s`: %w", filename, err)
 		}

pkg/component/controller/windowsstackcomponent.go

@@ -20,6 +20,8 @@ import (
 	"bytes"
 	"context"
 	"fmt"
+	"io/fs"
+	"path"
 	"path/filepath"
 	"reflect"
 	"strings"
@@ -173,12 +175,13 @@ func (n *WindowsStackComponent) Stop() error {
 // createWindowsStack creates windows stack
 
 func (n *WindowsStackComponent) createWindowsStack(newConfig windowsStackRenderingContext) error {
-	manifestDirectories, err := static.AssetDir("manifests/windows")
+	manifestDirectories, err := fs.ReadDir(static.WindowsManifests, ".")
 	if err != nil {
 		return fmt.Errorf("error retrieving manifests: %w", err)
 	}
-	for _, dir := range manifestDirectories {
-		manifestPaths, err := static.AssetDir(fmt.Sprintf("manifests/windows/%s", dir))
+	for _, entry := range manifestDirectories {
+		dir := entry.Name()
+		manifestPaths, err := fs.ReadDir(static.WindowsManifests, dir)
 		if err != nil {
 			return fmt.Errorf("error retrieving manifests: %w, will retry", err)
 		}
@@ -189,11 +192,12 @@ func (n *WindowsStackComponent) createWindowsStack(newConfig windowsStackRenderi
 			}
 		}
 
-		for _, filename := range manifestPaths {
+		for _, entry := range manifestPaths {
+			filename := entry.Name()
 			manifestName := fmt.Sprintf("windows-%s-%s", dir, filename)
 			output := bytes.NewBuffer([]byte{})
 			n.log.Debugf("Reading manifest template %s", manifestName)
-			contents, err := static.Asset(fmt.Sprintf("manifests/windows/%s/%s", dir, filename))
+			contents, err := fs.ReadFile(static.WindowsManifests, path.Join(dir, filename))
 			if err != nil {
 				return fmt.Errorf("can't unpack manifest %s: %w", manifestName, err)
 			}

static/assets.go

@@ -0,0 +1,49 @@
+/*
+Copyright 2024 k0s authors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package static
+
+import (
+	"embed"
+	"io/fs"
+	"path"
+)
+
+var (
+	//go:embed _crds
+	crds embed.FS
+	CRDs fs.FS = subFS(crds, "_crds")
+)
+
+var (
+	//go:embed manifests/calico
+	calicoManifests embed.FS
+	CalicoManifests fs.FS = subFS(calicoManifests, "manifests", "calico")
+)
+
+var (
+	//go:embed manifests/windows
+	windowsManifests embed.FS
+	WindowsManifests fs.FS = subFS(windowsManifests, "manifests", "windows")
+)
+
+func subFS(f fs.FS, segments ...string) fs.FS {
+	f, err := fs.Sub(f, path.Join(segments...))
+	if err != nil {
+		panic(err)
+	}
+	return f
+}