Update readme file and CI

.devcontainer/devcontainer.json

@@ -0,0 +1,18 @@
+{
+  "$schema": "https://raw.githubusercontent.com/devcontainers/spec/main/schemas/devContainer.base.schema.json",
+  "name": "default",
+  "image": "golang:1.22-bookworm",
+  "features": {
+    "ghcr.io/guiyomh/features/golangci-lint:0": {},
+    "ghcr.io/devcontainers/features/github-cli:1": {},
+    "ghcr.io/devcontainers/features/sshd:1": {}
+  },
+  "customizations": {
+    "vscode": {
+      "extensions": [
+        "streetsidesoftware.code-spell-checker"
+      ]
+    }
+  },
+  "postCreateCommand": "go mod download"
+}

.github/workflows/release.yml

@@ -36,7 +36,7 @@ jobs:
           tag: ${{ github.ref }}
 
       - if: matrix.os == 'linux' && matrix.arch == 'amd64'
-        run: mkdir ./out && ./${{ steps.values.outputs.binary-name }} build --index --target-dir ./out
+        run: mkdir ./out && ./${{ steps.values.outputs.binary-name }} build --index --disable-minification --target-dir ./out
       - if: matrix.os == 'linux' && matrix.arch == 'amd64'
         uses: actions/upload-artifact@v4
         with:
@@ -93,13 +93,12 @@ jobs:
           push: true
           platforms: linux/amd64,linux/arm/v7,linux/arm64/v8
           build-args: "APP_VERSION=${{ steps.slug.outputs.version }}"
-          tags: ghcr.io/${{ github.actor }}/${{ github.event.repository.name }}:${{ steps.slug.outputs.version }}
-#         tags: | # TODO: uncomment after the stable release
-#           tarampampam/error-pages:latest
-#           tarampampam/error-pages:${{ steps.slug.outputs.version }}
-#           tarampampam/error-pages:${{ steps.slug.outputs.version-major }}.${{ steps.slug.outputs.version-minor }}
-#           tarampampam/error-pages:${{ steps.slug.outputs.version-major }}
-#           ghcr.io/${{ github.actor }}/${{ github.event.repository.name }}:latest
-#           ghcr.io/${{ github.actor }}/${{ github.event.repository.name }}:${{ steps.slug.outputs.version }}
-#           ghcr.io/${{ github.actor }}/${{ github.event.repository.name }}:${{ steps.slug.outputs.version-major }}.${{ steps.slug.outputs.version-minor }}
-#           ghcr.io/${{ github.actor }}/${{ github.event.repository.name }}:${{ steps.slug.outputs.version-major }}
+          tags: |
+            tarampampam/error-pages:latest
+            tarampampam/error-pages:${{ steps.slug.outputs.version }}
+            tarampampam/error-pages:${{ steps.slug.outputs.version-major }}.${{ steps.slug.outputs.version-minor }}
+            tarampampam/error-pages:${{ steps.slug.outputs.version-major }}
+            ghcr.io/${{ github.actor }}/${{ github.event.repository.name }}:latest
+            ghcr.io/${{ github.actor }}/${{ github.event.repository.name }}:${{ steps.slug.outputs.version }}
+            ghcr.io/${{ github.actor }}/${{ github.event.repository.name }}:${{ steps.slug.outputs.version-major }}.${{ steps.slug.outputs.version-minor }}
+            ghcr.io/${{ github.actor }}/${{ github.event.repository.name }}:${{ steps.slug.outputs.version-major }}

Dockerfile

@@ -3,7 +3,7 @@
 # -✂- this stage is used to develop and build the application locally -------------------------------------------------
 FROM docker.io/library/golang:1.22-bookworm AS develop
 
-# use the /var/tmp as the GOPATH to reuse the modules cache
+# use the /var/tmp/go as the GOPATH to reuse the modules cache
 ENV GOPATH="/var/tmp/go"
 
 RUN set -x \
@@ -32,7 +32,10 @@ FROM develop AS compile
 # can be passed with any prefix (like `v1.2.3@GITHASH`), e.g.: `docker build --build-arg "APP_VERSION=v1.2.3" .`
 ARG APP_VERSION="undefined@docker"
 
-RUN --mount=type=bind,source=.,target=/src set -x \
+# copy the source code
+COPY . /src
+
+RUN set -x \
     && go generate ./... \
     && CGO_ENABLED=0 LDFLAGS="-s -w -X gh.tarampamp.am/error-pages/internal/appmeta.version=${APP_VERSION}" \
       go build -trimpath -ldflags "${LDFLAGS}" -o /tmp/error-pages ./cmd/error-pages/ \
@@ -45,10 +48,11 @@ FROM docker.io/library/alpine:3.20 AS rootfs
 WORKDIR /tmp/rootfs
 
 # prepare rootfs for runtime
-RUN --mount=type=bind,source=.,target=/src set -x \
-    && mkdir -p ./etc ./bin \
+RUN set -x \
+    && mkdir -p ./etc/ssl/certs ./bin \
     && echo 'appuser:x:10001:10001::/nonexistent:/sbin/nologin' > ./etc/passwd \
-    && echo 'appuser:x:10001:' > ./etc/group
+    && echo 'appuser:x:10001:' > ./etc/group \
+    && cp /etc/ssl/certs/ca-certificates.crt ./etc/ssl/certs/
 
 # take the binary from the compile stage
 COPY --from=compile /tmp/error-pages ./bin/error-pages
@@ -69,7 +73,7 @@ ARG APP_VERSION="undefined@docker"
 LABEL \
     # docs: https://github.com/opencontainers/image-spec/blob/master/annotations.md
     org.opencontainers.image.title="error-pages" \
-    org.opencontainers.image.description="Static server error pages in the docker image" \
+    org.opencontainers.image.description="Pretty server's error pages" \
     org.opencontainers.image.url="https://github.com/tarampampam/error-pages" \
     org.opencontainers.image.source="https://github.com/tarampampam/error-pages" \
     org.opencontainers.image.vendor="tarampampam" \
@@ -87,6 +91,8 @@ WORKDIR /opt
 # to find out which environment variables and CLI arguments are supported by the application, run the app
 # with the `--help` flag or refer to the documentation at https://github.com/tarampampam/error-pages#readme
 
+ENV LOG_LEVEL="warn"
+
 # docs: https://docs.docker.com/reference/dockerfile/#healthcheck
 HEALTHCHECK --interval=10s --start-interval=1s --start-period=5s --timeout=2s CMD [\
   "/bin/error-pages", "--log-format", "json", "healthcheck" \

go.mod

@@ -4,6 +4,7 @@ go 1.22
 
 require (
 	github.com/stretchr/testify v1.9.0
+	github.com/tdewolff/minify/v2 v2.20.35
 	github.com/urfave/cli-docs/v3 v3.0.0-alpha5
 	github.com/urfave/cli/v3 v3.0.0-alpha9
 	github.com/valyala/fasthttp v1.55.0
@@ -19,6 +20,7 @@ require (
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/rogpeppe/go-internal v1.12.0 // indirect
 	github.com/russross/blackfriday/v2 v2.1.0 // indirect
+	github.com/tdewolff/parse/v2 v2.7.15 // indirect
 	github.com/valyala/bytebufferpool v1.0.0 // indirect
 	github.com/xrash/smetrics v0.0.0-20240521201337-686a1a2994c1 // indirect
 	gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c // indirect

go.sum

@@ -26,6 +26,13 @@ github.com/russross/blackfriday/v2 v2.1.0 h1:JIOH55/0cWyOuilr9/qlrm0BSXldqnqwMsf
 github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
 github.com/stretchr/testify v1.9.0 h1:HtqpIVDClZ4nwg75+f6Lvsy/wHu+3BoSGCbBAcpTsTg=
 github.com/stretchr/testify v1.9.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
+github.com/tdewolff/minify/v2 v2.20.35 h1:/Vq/oivpkFyi2PViD25XHZZbJz+eO4OmPSgePex1kBU=
+github.com/tdewolff/minify/v2 v2.20.35/go.mod h1:L1VYef/jwKw6Wwyk5A+T0mBjjn3mMPgmjjA688RNsxU=
+github.com/tdewolff/parse/v2 v2.7.15 h1:hysDXtdGZIRF5UZXwpfn3ZWRbm+ru4l53/ajBRGpCTw=
+github.com/tdewolff/parse/v2 v2.7.15/go.mod h1:3FbJWZp3XT9OWVN3Hmfp0p/a08v4h8J9W1aghka0soA=
+github.com/tdewolff/test v1.0.11-0.20231101010635-f1265d231d52/go.mod h1:6DAvZliBAAnD7rhVgwaM7DE5/d9NMOAJ09SqYqeK4QE=
+github.com/tdewolff/test v1.0.11-0.20240106005702-7de5f7df4739 h1:IkjBCtQOOjIn03u/dMQK9g+Iw9ewps4mCl1nB8Sscbo=
+github.com/tdewolff/test v1.0.11-0.20240106005702-7de5f7df4739/go.mod h1:XPuWBzvdUzhCuxWO1ojpXsyzsA5bFoS3tO/Q3kFuTG8=
 github.com/urfave/cli-docs/v3 v3.0.0-alpha5 h1:H1oWnR2/GN0dNm2PVylws+GxSOD6YOwW/jI5l78YfPk=
 github.com/urfave/cli-docs/v3 v3.0.0-alpha5/go.mod h1:AIqom6Q60U4tiqHp41i7+/AB2XHgi1WvQ7jOFlccmZ4=
 github.com/urfave/cli/v3 v3.0.0-alpha9 h1:P0RMy5fQm1AslQS+XCmy9UknDXctOmG/q/FZkUFnJSo=

internal/cli/app.go

@@ -6,7 +6,6 @@ import (
 	"runtime"
 	"strings"
 
-	_ "github.com/urfave/cli-docs/v3" // required for `go generate` to work
 	"github.com/urfave/cli/v3"
 
 	"gh.tarampamp.am/error-pages/internal/appmeta"
@@ -17,7 +16,7 @@ import (
 	"gh.tarampamp.am/error-pages/internal/logger"
 )
 
-//go:generate go run update_readme.go
+//go:generate go run app_generate.go
 
 // NewApp creates a new console application.
 func NewApp(appName string) *cli.Command { //nolint:funlen
@@ -25,7 +24,7 @@ func NewApp(appName string) *cli.Command { //nolint:funlen
 		logLevelFlag = cli.StringFlag{
 			Name:     "log-level",
 			Value:    logger.InfoLevel.String(),
-			Usage:    "logging level (" + strings.Join(logger.LevelStrings(), "/") + ")",
+			Usage:    "Logging level (" + strings.Join(logger.LevelStrings(), "/") + ")",
 			Sources:  cli.EnvVars("LOG_LEVEL"),
 			OnlyOnce: true,
 			Config:   cli.StringConfig{TrimSpace: true},
@@ -41,7 +40,7 @@ func NewApp(appName string) *cli.Command { //nolint:funlen
 		logFormatFlag = cli.StringFlag{
 			Name:     "log-format",
 			Value:    logger.ConsoleFormat.String(),
-			Usage:    "logging format (" + strings.Join(logger.FormatStrings(), "/") + ")",
+			Usage:    "Logging format (" + strings.Join(logger.FormatStrings(), "/") + ")",
 			Sources:  cli.EnvVars("LOG_FORMAT"),
 			OnlyOnce: true,
 			Config:   cli.StringConfig{TrimSpace: true},
@@ -80,7 +79,7 @@ func NewApp(appName string) *cli.Command { //nolint:funlen
 			serve.NewCommand(log),
 			build.NewCommand(log),
 			healthcheck.NewCommand(log, healthcheck.NewHTTPHealthChecker()),
-			perftest.NewCommand(log),
+			perftest.NewCommand(),
 		},
 		Version: fmt.Sprintf("%s (%s)", appmeta.Version(), runtime.Version()),
 		Flags: []cli.Flag{ // global flags

internal/cli/app_generate.go

@@ -1,5 +1,4 @@
-//go:build ignore
-// +build ignore
+//go:build generate
 
 package main
 
@@ -17,8 +16,10 @@ func main() {
 	if stat, err := os.Stat(readmePath); err == nil && stat.Mode().IsRegular() {
 		if err = cliDocs.ToTabularToFileBetweenTags(cli.NewApp(""), "error-pages", readmePath); err != nil {
 			panic(err)
+		} else {
+			println("✔ cli docs updated successfully")
 		}
 	} else if err != nil {
-		println("readme file not found, cli docs not updated:", err.Error())
+		println("⚠ readme file not found, cli docs not updated:", err.Error())
 	}
 }

internal/cli/build/command.go

@@ -39,21 +39,24 @@ func NewCommand(log *logger.Logger) *cli.Command { //nolint:funlen,gocognit
 		cmd command
 		cfg = config.New()
 
-		addTplFlag      = shared.AddTemplatesFlag
-		disableTplFlag  = shared.DisableTemplateNamesFlag
-		addCodeFlag     = shared.AddHTTPCodesFlag
-		disableL10nFlag = shared.DisableL10nFlag
-		createIndexFlag = cli.BoolFlag{
-			Name:    "index",
-			Aliases: []string{"i"},
-			Usage:   "generate index.html file with links to all error pages",
+		addTplFlag              = shared.AddTemplatesFlag
+		disableTplFlag          = shared.DisableTemplateNamesFlag
+		addCodeFlag             = shared.AddHTTPCodesFlag
+		disableL10nFlag         = shared.DisableL10nFlag
+		disableMinificationFlag = shared.DisableMinificationFlag
+		createIndexFlag         = cli.BoolFlag{
+			Name:     "index",
+			Aliases:  []string{"i"},
+			Usage:    "Generate index.html file with links to all error pages",
+			Category: shared.CategoryBuild,
 		}
 		targetDirFlag = cli.StringFlag{
 			Name:     "target-dir",
 			Aliases:  []string{"out", "dir", "o"},
-			Usage:    "directory to put the built error pages into",
+			Usage:    "Directory to put the built error pages into",
 			Value:    ".", // current directory by default
 			Config:   cli.StringConfig{TrimSpace: true},
+			Category: shared.CategoryBuild,
 			OnlyOnce: true,
 			Validator: func(dir string) error {
 				if dir == "" {
@@ -79,6 +82,7 @@ func NewCommand(log *logger.Logger) *cli.Command { //nolint:funlen,gocognit
 		Usage:   "Build the static error pages and put them into a specified directory",
 		Action: func(ctx context.Context, c *cli.Command) error {
 			cfg.L10n.Disable = c.Bool(disableL10nFlag.Name)
+			cfg.DisableMinification = c.Bool(disableMinificationFlag.Name)
 			cmd.opt.createIndex = c.Bool(createIndexFlag.Name)
 			cmd.opt.targetDirAbsPath, _ = filepath.Abs(c.String(targetDirFlag.Name)) // an error checked by [os.Stat] validator
 
@@ -138,13 +142,14 @@ func NewCommand(log *logger.Logger) *cli.Command { //nolint:funlen,gocognit
 			&disableL10nFlag,
 			&createIndexFlag,
 			&targetDirFlag,
+			&disableMinificationFlag,
 		},
 	}
 
 	return cmd.c
 }
 
-func (cmd *command) Run( //nolint:funlen
+func (cmd *command) Run( //nolint:funlen,gocognit
 	ctx context.Context,
 	log *logger.Logger,
 	cfg *config.Config,
@@ -170,13 +175,21 @@ func (cmd *command) Run( //nolint:funlen
 
 			var outFilePath = path.Join(cmd.opt.targetDirAbsPath, templateName, code+".html")
 
-			if content, renderErr := appTemplate.Render(templateContent, appTemplate.Props{
+			if content, renderErr := appTemplate.Render(templateContent, appTemplate.Props{ //nolint:nestif
 				Code:               uint16(codeAsUint),
 				Message:            codeDescription.Message,
 				Description:        codeDescription.Description,
 				L10nDisabled:       cfg.L10n.Disable,
 				ShowRequestDetails: false,
 			}); renderErr == nil {
+				if !cfg.DisableMinification {
+					if mini, minErr := appTemplate.MiniHTML(content); minErr != nil {
+						log.Warn("Cannot minify the content", logger.Error(minErr))
+					} else {
+						content = mini
+					}
+				}
+
 				if err := os.WriteFile(outFilePath, []byte(content), os.FileMode(0664)); err != nil { //nolint:mnd
 					return err
 				}

internal/cli/perftest/command.go

@@ -1,32 +1,59 @@
 package perftest
 
 import (
+	"bytes"
 	"context"
 	"errors"
 	"fmt"
 	"io"
-	"math/rand"
-	"net/http"
+	"math"
+	"os"
+	"os/exec"
 	"runtime"
-	"sync"
-	"sync/atomic"
+	"strconv"
 	"time"
 
 	"github.com/urfave/cli/v3"
 
 	"gh.tarampamp.am/error-pages/internal/cli/shared"
-	"gh.tarampamp.am/error-pages/internal/logger"
 )
 
+const wrkOneCodeTestLua = `
+local formats = { 'application/json', 'application/xml', 'text/html', 'text/plain' }
+
+request = function()
+		wrk.headers["User-Agent"] = "wrk"
+    wrk.headers["X-Namespace"] = "NAMESPACE_" .. tostring(math.random(0, 99999999))
+    wrk.headers["X-Request-ID"] = "REQ_ID_" .. tostring(math.random(0, 99999999))
+    wrk.headers["Content-Type"] = formats[ math.random( 0, #formats - 1 ) ]
+
+    return wrk.format("GET", "/500.html?rnd=" .. tostring(math.random(0, 99999999)), nil, nil)
+end
+`
+
+//nolint:lll
+const bombDifferentCodes = `
+local formats = { 'application/json', 'application/xml', 'text/html', 'text/plain' }
+
+request = function()
+		wrk.headers["User-Agent"] = "wrk"
+    wrk.headers["X-Namespace"] = "NAMESPACE_" .. tostring(math.random(0, 99999999))
+    wrk.headers["X-Request-ID"] = "REQ_ID_" .. tostring(math.random(0, 99999999))
+    wrk.headers["Content-Type"] = formats[ math.random( 0, #formats - 1 ) ]
+
+    return wrk.format("GET", "/" .. tostring(math.random(400, 599)) .. ".html?rnd=" .. tostring(math.random(0, 99999999)), nil, nil)
+end
+`
+
 // NewCommand creates `perftest` command.
-func NewCommand(log *logger.Logger) *cli.Command { //nolint:funlen,gocognit
+func NewCommand() *cli.Command { //nolint:funlen
 	var (
 		portFlag     = shared.ListenPortFlag
 		durationFlag = cli.DurationFlag{
 			Name:    "duration",
 			Aliases: []string{"d"},
-			Usage:   "duration of the test",
-			Value:   10 * time.Second, //nolint:mnd
+			Usage:   "Duration of test",
+			Value:   15 * time.Second, //nolint:mnd
 			Validator: func(d time.Duration) error {
 				if d <= time.Second {
 					return errors.New("duration can't be less than 1 second")
@@ -38,11 +65,28 @@ func NewCommand(log *logger.Logger) *cli.Command { //nolint:funlen,gocognit
 		threadsFlag = cli.UintFlag{
 			Name:    "threads",
 			Aliases: []string{"t"},
-			Usage:   "number of threads",
-			Value:   max(2, uint64(runtime.NumCPU()/2)), //nolint:mnd
+			Usage:   "Number of threads to use",
+			Value:   max(2, uint64(math.Round(float64(runtime.NumCPU())/1.3))), //nolint:mnd
 			Validator: func(u uint64) error {
 				if u == 0 {
 					return errors.New("threads number can't be zero")
+				} else if u > math.MaxUint16 {
+					return errors.New("threads number can't be greater than 65535")
+				}
+
+				return nil
+			},
+		}
+		connectionsFlag = cli.UintFlag{
+			Name:    "connections",
+			Aliases: []string{"c"},
+			Usage:   "Number of connections to keep open",
+			Value:   max(16, uint64(runtime.NumCPU()*25)), //nolint:mnd
+			Validator: func(u uint64) error {
+				if u == 0 {
+					return errors.New("threads number can't be zero")
+				} else if u > math.MaxUint16 {
+					return errors.New("threads number can't be greater than 65535")
 				}
 
 				return nil
@@ -52,97 +96,47 @@ func NewCommand(log *logger.Logger) *cli.Command { //nolint:funlen,gocognit
 
 	return &cli.Command{
 		Name:    "perftest",
-		Aliases: []string{"perf", "test"},
+		Aliases: []string{"perf", "benchmark", "bench"},
 		Hidden:  true,
-		Usage:   "Simple performance (load) test for the HTTP server",
-		Action: func(ctx context.Context, c *cli.Command) error { // TODO: use fasthttp.Client
-			var (
-				perfCtx, cancel = context.WithTimeout(ctx, c.Duration(durationFlag.Name))
-				startedAt       = time.Now()
-
-				wg      sync.WaitGroup
-				success atomic.Uint64
-				failed  atomic.Uint64
-			)
-
-			defer func() {
-				cancel()
-
-				log.Info("Summary",
-					logger.Uint64("success", success.Load()),
-					logger.Uint64("failed", failed.Load()),
-					logger.Duration("duration", time.Since(startedAt)),
-					logger.Float64("RPS", float64(success.Load()+failed.Load())/time.Since(startedAt).Seconds()),
-					logger.Float64("errors rate", float64(failed.Load())/float64(success.Load()+failed.Load())*100), //nolint:mnd
-				)
-			}()
-
-			log.Info("Running test",
-				logger.Uint64("threads", c.Uint(threadsFlag.Name)),
-				logger.Duration("duration", c.Duration(durationFlag.Name)),
-			)
-
-			var httpClient = &http.Client{
-				Transport: &http.Transport{MaxConnsPerHost: max(2, int(c.Uint(threadsFlag.Name))-1)}, //nolint:mnd
-				Timeout:   c.Duration(durationFlag.Name) + time.Second,
+		Usage:   "Performance (load) test for the HTTP server (locally installed wrk is required)",
+		Action: func(ctx context.Context, c *cli.Command) error {
+			var wrkBinPath, lErr = exec.LookPath("wrk")
+			if lErr != nil {
+				return fmt.Errorf("seems like wrk (https://github.com/wg/wrk) is not installed: %w", lErr)
 			}
 
-			for i := uint64(0); i < c.Uint(threadsFlag.Name); i++ {
-				wg.Add(1)
+			var runTest = func(scriptContent string) error {
+				if stdOut, stdErr, err := wrkRunTest(ctx,
+					wrkBinPath,
+					uint16(c.Uint(threadsFlag.Name)),
+					uint16(c.Uint(connectionsFlag.Name)),
+					c.Duration(durationFlag.Name),
+					uint16(c.Uint(portFlag.Name)),
+					scriptContent,
+				); err != nil {
+					var errData, _ = io.ReadAll(stdErr)
 
-				go func(log *logger.Logger) {
-					defer wg.Done()
+					return fmt.Errorf("failed to execute the test: %w (%s)", err, string(errData))
+				} else {
+					var outData, _ = io.ReadAll(stdOut)
 
-					if perfCtx.Err() != nil {
-						return
-					}
+					printf("Test completed successfully. Here is the output:\n\n%s\n", string(outData))
+				}
 
-					var req, rErr = makeRequest(perfCtx, uint16(c.Uint(portFlag.Name)))
-					if rErr != nil {
-						log.Error("Failed to create a new request", logger.Error(rErr))
-
-						return
-					}
-
-					for {
-						var sentAt = time.Now()
-
-						var resp, respErr = httpClient.Do(req)
-						if resp != nil {
-							if _, err := io.Copy(io.Discard, resp.Body); err != nil && !errIsDone(err) {
-								log.Error("Failed to read response body", logger.Error(err))
-							}
-
-							if err := resp.Body.Close(); err != nil && !errIsDone(err) {
-								log.Error("Failed to close response body", logger.Error(err))
-							}
-						}
-
-						if respErr != nil {
-							if errIsDone(respErr) {
-								return
-							}
-
-							log.Error("Request failed", logger.Error(respErr))
-							failed.Add(1)
-
-							continue
-						}
-
-						log.Debug("Response received",
-							logger.String("status", resp.Status),
-							logger.Duration("duration", time.Since(sentAt)),
-							logger.Int64("size", resp.ContentLength),
-							logger.Uint64("success", success.Load()),
-							logger.Uint64("failed", failed.Load()),
-						)
-
-						success.Add(1)
-					}
-				}(log.Named(fmt.Sprintf("thread-%d", i)))
+				return nil
 			}
 
-			wg.Wait()
+			printf("Starting the test to bomb ONE PAGE (code). Please, be patient...\n")
+
+			if err := runTest(wrkOneCodeTestLua); err != nil {
+				return err
+			}
+
+			printf("Starting the test to bomb DIFFERENT PAGES (codes). Please, be patient...\n")
+
+			if err := runTest(bombDifferentCodes); err != nil {
+				return err
+			}
 
 			return nil
 		},
@@ -150,54 +144,51 @@ func NewCommand(log *logger.Logger) *cli.Command { //nolint:funlen,gocognit
 			&portFlag,
 			&durationFlag,
 			&threadsFlag,
+			&connectionsFlag,
 		},
 	}
 }
 
-// randomIntBetween returns a random integer between min and max.
-func randomIntBetween(min, max int) int { return min + rand.Intn(max-min) } //nolint:gosec
+func printf(format string, args ...any) { fmt.Printf(format, args...) } //nolint:forbidigo
 
-// makeRequest creates a new HTTP request for the performance test.
-func makeRequest(ctx context.Context, port uint16) (*http.Request, error) {
-	var req, rErr = http.NewRequestWithContext(ctx,
-		http.MethodGet,
-		fmt.Sprintf(
-			"http://127.0.0.1:%d/%d.html?rnd=%d", // for load testing purposes only
-			port,
-			randomIntBetween(400, 418),       //nolint:mnd
-			randomIntBetween(1, 999_999_999), //nolint:mnd
-		),
-		http.NoBody,
+func wrkRunTest(
+	ctx context.Context,
+	wrkBinPath string,
+	threadsCount, connectionsCount uint16,
+	duration time.Duration,
+	port uint16,
+	scriptContent string,
+) (io.Reader, io.Reader, error) {
+	var tmpFile, tErr = os.CreateTemp("", "ep-perf-one-page")
+	if tErr != nil {
+		return nil, nil, fmt.Errorf("failed to create a temporary file: %w", tErr)
+	}
+
+	defer func() {
+		_ = tmpFile.Close()
+		_ = os.Remove(tmpFile.Name())
+	}()
+
+	if _, err := tmpFile.WriteString(scriptContent); err != nil {
+		return nil, nil, fmt.Errorf("failed to write to a temporary file: %w", err)
+	}
+
+	if err := tmpFile.Close(); err != nil {
+		return nil, nil, err
+	}
+
+	var stdout, stderr bytes.Buffer
+
+	var cmd = exec.CommandContext(ctx, wrkBinPath, //nolint:gosec
+		"--timeout", "1s",
+		"--threads", strconv.FormatUint(uint64(threadsCount), 10),
+		"--connections", strconv.FormatUint(uint64(connectionsCount), 10),
+		"--duration", duration.String(),
+		"--script", tmpFile.Name(),
+		fmt.Sprintf("http://127.0.0.1:%d/", port),
 	)
 
-	if rErr != nil {
-		return nil, rErr
-	}
+	cmd.Stdout, cmd.Stderr = &stdout, &stderr
 
-	req.Header.Set("Connection", "keep-alive")
-	req.Header.Set("User-Agent", "perftest")
-	req.Header.Set("X-Namespace", fmt.Sprintf("namespace-%d", randomIntBetween(1, 999_999_999))) //nolint:mnd
-	req.Header.Set("X-Request-ID", fmt.Sprintf("req-id-%d", randomIntBetween(1, 999_999_999)))   //nolint:mnd
-
-	var contentType string
-
-	switch randomIntBetween(1, 4) { //nolint:mnd
-	case 1:
-		contentType = "application/json"
-	case 2: //nolint:mnd
-		contentType = "application/xml"
-	case 3: //nolint:mnd
-		contentType = "text/html"
-	default:
-		contentType = "text/plain"
-	}
-
-	req.Header.Set("Content-Type", contentType)
-
-	return req, nil
-}
-
-// errIsDone checks if the error is a context.DeadlineExceeded or context.Canceled.
-func errIsDone(err error) bool {
-	return errors.Is(err, context.DeadlineExceeded) || errors.Is(err, context.Canceled)
+	return &stdout, &stderr, cmd.Run() // execute
 }

internal/cli/serve/command.go

@@ -38,33 +38,37 @@ func NewCommand(log *logger.Logger) *cli.Command { //nolint:funlen,gocognit,gocy
 	)
 
 	var (
-		addrFlag        = shared.ListenAddrFlag
-		portFlag        = shared.ListenPortFlag
-		addTplFlag      = shared.AddTemplatesFlag
-		disableTplFlag  = shared.DisableTemplateNamesFlag
-		addCodeFlag     = shared.AddHTTPCodesFlag
-		disableL10nFlag = shared.DisableL10nFlag
-		jsonFormatFlag  = cli.StringFlag{
+		addrFlag                = shared.ListenAddrFlag
+		portFlag                = shared.ListenPortFlag
+		addTplFlag              = shared.AddTemplatesFlag
+		disableTplFlag          = shared.DisableTemplateNamesFlag
+		addCodeFlag             = shared.AddHTTPCodesFlag
+		disableL10nFlag         = shared.DisableL10nFlag
+		disableMinificationFlag = shared.DisableMinificationFlag
+		jsonFormatFlag          = cli.StringFlag{
 			Name: "json-format",
-			Usage: "override the default error page response in JSON format (Go templates are supported; the error " +
+			Usage: "Override the default error page response in JSON format (Go templates are supported; the error " +
 				"page will use this template if the client requests JSON content type)",
 			Sources:  env("RESPONSE_JSON_FORMAT"),
+			Category: shared.CategoryFormats,
 			OnlyOnce: true,
 			Config:   trim,
 		}
 		xmlFormatFlag = cli.StringFlag{
 			Name: "xml-format",
-			Usage: "override the default error page response in XML format (Go templates are supported; the error " +
+			Usage: "Override the default error page response in XML format (Go templates are supported; the error " +
 				"page will use this template if the client requests XML content type)",
 			Sources:  env("RESPONSE_XML_FORMAT"),
+			Category: shared.CategoryFormats,
 			OnlyOnce: true,
 			Config:   trim,
 		}
 		plainTextFormatFlag = cli.StringFlag{
 			Name: "plaintext-format",
-			Usage: "override the default error page response in plain text format (Go templates are supported; the " +
+			Usage: "Override the default error page response in plain text format (Go templates are supported; the " +
 				"error page will use this template if the client requests plain text content type or does not specify any)",
 			Sources:  env("RESPONSE_PLAINTEXT_FORMAT"),
+			Category: shared.CategoryFormats,
 			OnlyOnce: true,
 			Config:   trim,
 		}
@@ -72,17 +76,19 @@ func NewCommand(log *logger.Logger) *cli.Command { //nolint:funlen,gocognit,gocy
 			Name:    "template-name",
 			Aliases: []string{"t"},
 			Value:   cfg.TemplateName,
-			Usage: "name of the template to use for rendering error pages (built-in templates: " +
+			Usage: "Name of the template to use for rendering error pages (built-in templates: " +
 				strings.Join(cfg.Templates.Names(), ", ") + ")",
 			Sources:  env("TEMPLATE_NAME"),
+			Category: shared.CategoryTemplates,
 			OnlyOnce: true,
 			Config:   trim,
 		}
 		defaultCodeToRenderFlag = cli.UintFlag{
-			Name:    "default-error-page",
-			Usage:   "the code of the default (index page, when a code is not specified) error page to render",
-			Value:   uint64(cfg.DefaultCodeToRender),
-			Sources: env("DEFAULT_ERROR_PAGE"),
+			Name:     "default-error-page",
+			Usage:    "The code of the default (index page, when a code is not specified) error page to render",
+			Value:    uint64(cfg.DefaultCodeToRender),
+			Sources:  env("DEFAULT_ERROR_PAGE"),
+			Category: shared.CategoryCodes,
 			Validator: func(code uint64) error {
 				if code > 999 { //nolint:mnd
 					return fmt.Errorf("wrong HTTP code [%d] for the default error page", code)
@@ -94,17 +100,19 @@ func NewCommand(log *logger.Logger) *cli.Command { //nolint:funlen,gocognit,gocy
 		}
 		sendSameHTTPCodeFlag = cli.BoolFlag{
 			Name: "send-same-http-code",
-			Usage: "the HTTP response should have the same status code as the requested error page (by default, " +
+			Usage: "The HTTP response should have the same status code as the requested error page (by default, " +
 				"every response with an error page will have a status code of 200)",
 			Value:    cfg.RespondWithSameHTTPCode,
 			Sources:  env("SEND_SAME_HTTP_CODE"),
+			Category: shared.CategoryOther,
 			OnlyOnce: true,
 		}
 		showDetailsFlag = cli.BoolFlag{
 			Name:     "show-details",
-			Usage:    "show request details in the error page response (if supported by the template)",
+			Usage:    "Show request details in the error page response (if supported by the template)",
 			Value:    cfg.ShowDetails,
 			Sources:  env("SHOW_DETAILS"),
+			Category: shared.CategoryOther,
 			OnlyOnce: true,
 		}
 		proxyHeadersListFlag = cli.StringFlag{
@@ -122,14 +130,16 @@ func NewCommand(log *logger.Logger) *cli.Command { //nolint:funlen,gocognit,gocy
 
 				return nil
 			},
+			Category: shared.CategoryOther,
 			OnlyOnce: true,
 			Config:   trim,
 		}
 		rotationModeFlag = cli.StringFlag{
 			Name:     "rotation-mode",
 			Value:    config.RotationModeDisabled.String(),
-			Usage:    "templates automatic rotation mode (" + strings.Join(config.RotationModeStrings(), "/") + ")",
+			Usage:    "Templates automatic rotation mode (" + strings.Join(config.RotationModeStrings(), "/") + ")",
 			Sources:  env("TEMPLATES_ROTATION_MODE"),
+			Category: shared.CategoryTemplates,
 			OnlyOnce: true,
 			Config:   trim,
 			Validator: func(s string) error {
@@ -142,26 +152,27 @@ func NewCommand(log *logger.Logger) *cli.Command { //nolint:funlen,gocognit,gocy
 		}
 		readBufferSizeFlag = cli.UintFlag{
 			Name: "read-buffer-size",
-			Usage: "per-connection buffer size in bytes for reading requests, this also limits the maximum header size " +
+			Usage: "Per-connection buffer size in bytes for reading requests, this also limits the maximum header size " +
 				"(increase this buffer if your clients send multi-KB Request URIs and/or multi-KB headers (e.g., " +
 				"large cookies), note that increasing this value will increase memory consumption)",
 			Value:    1024 * 5, //nolint:mnd // 5 KB
 			Sources:  env("READ_BUFFER_SIZE"),
+			Category: shared.CategoryOther,
 			OnlyOnce: true,
 		}
 	)
 
 	// override some flag usage messages
-	addrFlag.Usage = "the HTTP server will listen on this IP (v4 or v6) address (set 127.0.0.1 for localhost, " +
+	addrFlag.Usage = "The HTTP server will listen on this IP (v4 or v6) address (set 127.0.0.1/::1 for localhost, " +
 		"0.0.0.0 to listen on all interfaces, or specify a custom IP)"
-	portFlag.Usage = "the TCP port number for the HTTP server to listen on (0-65535)"
+	portFlag.Usage = "The TCP port number for the HTTP server to listen on (0-65535)"
 
 	disableL10nFlag.Value = cfg.L10n.Disable // set the default value depending on the configuration
 
 	cmd.c = &cli.Command{
 		Name:    "serve",
 		Aliases: []string{"s", "server", "http"},
-		Usage:   "Start HTTP server",
+		Usage:   "Please start the HTTP server to serve the error pages. You can configure various options - please RTFM :D",
 		Suggest: true,
 		Action: func(ctx context.Context, c *cli.Command) error {
 			cmd.opt.http.addr = c.String(addrFlag.Name)
@@ -172,6 +183,7 @@ func NewCommand(log *logger.Logger) *cli.Command { //nolint:funlen,gocognit,gocy
 			cfg.RespondWithSameHTTPCode = c.Bool(sendSameHTTPCodeFlag.Name)
 			cfg.RotationMode, _ = config.ParseRotationMode(c.String(rotationModeFlag.Name))
 			cfg.ShowDetails = c.Bool(showDetailsFlag.Name)
+			cfg.DisableMinification = c.Bool(disableMinificationFlag.Name)
 
 			{ // override default JSON, XML, and PlainText formats
 				if c.IsSet(jsonFormatFlag.Name) {
@@ -293,6 +305,7 @@ func NewCommand(log *logger.Logger) *cli.Command { //nolint:funlen,gocognit,gocy
 			&proxyHeadersListFlag,
 			&rotationModeFlag,
 			&readBufferSizeFlag,
+			&disableMinificationFlag,
 		},
 	}
 

internal/cli/serve/command_test.go

@@ -36,7 +36,7 @@ func TestCommand_Run(t *testing.T) {
 			"--add-template", "./testdata/foo-template.html",
 			"--disable-template", "ghost",
 			"--disable-template", "<unknown>",
-			"--add-http-code", "200=Code/Description",
+			"--add-code", "200=Code/Description",
 			"--json-format", "json format",
 			"--xml-format", "xml format",
 			"--plaintext-format", "plaintext format",

internal/cli/shared/flags.go

@@ -11,6 +11,15 @@ import (
 	"gh.tarampamp.am/error-pages/internal/config"
 )
 
+const (
+	CategoryHTTP      = "HTTP:"
+	CategoryTemplates = "TEMPLATES:"
+	CategoryCodes     = "HTTP CODES:"
+	CategoryFormats   = "FORMATS:"
+	CategoryBuild     = "BUILD:"
+	CategoryOther     = "OTHER:"
+)
+
 // Note: Don't use pointers for flags, because they have own state which is not thread-safe.
 // https://github.com/urfave/cli/issues/1926
 
@@ -20,6 +29,7 @@ var ListenAddrFlag = cli.StringFlag{
 	Usage:    "IP (v4 or v6) address to listen on",
 	Value:    "0.0.0.0", // bind to all interfaces by default
 	Sources:  cli.EnvVars("LISTEN_ADDR"),
+	Category: CategoryHTTP,
 	OnlyOnce: true,
 	Config:   cli.StringConfig{TrimSpace: true},
 	Validator: func(ip string) error {
@@ -41,6 +51,7 @@ var ListenPortFlag = cli.UintFlag{
 	Usage:    "TCP port number",
 	Value:    8080, // default port number
 	Sources:  cli.EnvVars("LISTEN_PORT"),
+	Category: CategoryHTTP,
 	OnlyOnce: true,
 	Validator: func(port uint64) error {
 		if port == 0 || port > 65535 {
@@ -53,9 +64,10 @@ var ListenPortFlag = cli.UintFlag{
 
 var AddTemplatesFlag = cli.StringSliceFlag{
 	Name: "add-template",
-	Usage: "to add a new template, provide the path to the file using this flag (the filename without the extension " +
+	Usage: "To add a new template, provide the path to the file using this flag (the filename without the extension " +
 		"will be used as the template name)",
-	Config: cli.StringConfig{TrimSpace: true},
+	Config:   cli.StringConfig{TrimSpace: true},
+	Category: CategoryTemplates,
 	Validator: func(paths []string) error {
 		for _, path := range paths {
 			if path == "" {
@@ -72,18 +84,19 @@ var AddTemplatesFlag = cli.StringSliceFlag{
 }
 
 var DisableTemplateNamesFlag = cli.StringSliceFlag{
-	Name:   "disable-template",
-	Usage:  "disable the specified template by its name (useful to disable the built-in templates and use only custom ones)",
-	Config: cli.StringConfig{TrimSpace: true},
+	Name:     "disable-template",
+	Usage:    "Disable the specified template by its name (useful to disable the built-in templates and use only custom ones)",
+	Config:   cli.StringConfig{TrimSpace: true},
+	Category: CategoryTemplates,
 }
 
 var AddHTTPCodesFlag = cli.StringMapFlag{
-	Name:    "add-http-code",
-	Aliases: []string{"add-code"},
-	Usage: "to add a new HTTP status code, provide the code and its message/description using this flag (the format " +
+	Name: "add-code",
+	Usage: "To add a new HTTP status code, provide the code and its message/description using this flag (the format " +
 		"should be '%code%=%message%/%description%'; the code may contain a wildcard '*' to cover multiple codes at " +
 		"once, for example, '4**' will cover all 4xx codes unless a more specific code is described previously)",
-	Config: cli.StringConfig{TrimSpace: true},
+	Config:   cli.StringConfig{TrimSpace: true},
+	Category: CategoryCodes,
 	Validator: func(codes map[string]string) error {
 		for code, msgAndDesc := range codes {
 			if code == "" {
@@ -128,7 +141,16 @@ func ParseHTTPCodes(codes map[string]string) map[string]config.CodeDescription {
 
 var DisableL10nFlag = cli.BoolFlag{
 	Name:     "disable-l10n",
-	Usage:    "disable localization of error pages (if the template supports localization)",
+	Usage:    "Disable localization of error pages (if the template supports localization)",
 	Sources:  cli.EnvVars("DISABLE_L10N"),
+	Category: CategoryOther,
+	OnlyOnce: true,
+}
+
+var DisableMinificationFlag = cli.BoolFlag{
+	Name:     "disable-minification",
+	Usage:    "Disable the minification of HTML pages, including CSS, SVG, and JS (may be useful for debugging)",
+	Sources:  cli.EnvVars("DISABLE_MINIFICATION"),
+	Category: CategoryOther,
 	OnlyOnce: true,
 }

internal/cli/shared/flags_test.go

@@ -122,7 +122,7 @@ func TestAddHTTPCodesFlag(t *testing.T) {
 
 	var flag = shared.AddHTTPCodesFlag
 
-	assert.Equal(t, "add-http-code", flag.Name)
+	assert.Equal(t, "add-code", flag.Name)
 
 	for name, tt := range map[string]struct {
 		giveValue  map[string]string
@@ -216,3 +216,12 @@ func TestDisableL10nFlag(t *testing.T) {
 	assert.Equal(t, "disable-l10n", flag.Name)
 	assert.Contains(t, flag.Sources.String(), "DISABLE_L10N")
 }
+
+func TestDisableMinificationFlag(t *testing.T) {
+	t.Parallel()
+
+	var flag = shared.DisableMinificationFlag
+
+	assert.Equal(t, "disable-minification", flag.Name)
+	assert.Contains(t, flag.Sources.String(), "DISABLE_MINIFICATION")
+}

internal/config/config.go

@@ -56,6 +56,9 @@ type Config struct {
 	// ShowDetails determines whether to show additional details in the error response, extracted from the
 	// incoming request (if supported by the template).
 	ShowDetails bool
+
+	// DisableMinification determines whether to disable minification of the rendered content (e.g., HTML, CSS) or not.
+	DisableMinification bool
 }
 
 const defaultJSONFormat string = `{

internal/config/config_test.go

@@ -24,6 +24,7 @@ func TestNew(t *testing.T) {
 		assert.NotEmpty(t, cfg.TemplateName)
 		assert.True(t, cfg.Templates.Has(cfg.TemplateName))
 		assert.Equal(t, uint16(http.StatusNotFound), cfg.DefaultCodeToRender)
+		assert.False(t, cfg.DisableMinification)
 	})
 
 	t.Run("changing cfg1 should not affect cfg2", func(t *testing.T) {

internal/http/handlers/error_page/handler.go

@@ -175,6 +175,14 @@ func New(cfg *config.Config, log *logger.Logger) (_ fasthttp.RequestHandler, clo
 							err.Error(),
 						))
 					} else {
+						if !cfg.DisableMinification {
+							if mini, minErr := template.MiniHTML(content); minErr != nil {
+								log.Warn("HTML minification failed", logger.Error(minErr))
+							} else {
+								content = mini
+							}
+						}
+
 						cache.Put(tpl, tplProps, []byte(content))
 
 						write(ctx, log, content)

internal/http/handlers/error_page/handler_test.go

@@ -48,7 +48,7 @@ func TestHandler(t *testing.T) {
 			wantStatusCode: http.StatusOK,
 			wantHeaders:    map[string]string{"Content-Type": "text/html; charset=utf-8"},
 			wantBodyIncludes: []string{
-				"<!DOCTYPE html>",
+				"<!doctype html>",
 				"<title>407: Proxy Authentication Required",
 				"Proxy Authentication Required",
 			},

internal/http/server.go

@@ -51,7 +51,7 @@ func NewServer(log *logger.Logger, readBufferSize uint) Server {
 }
 
 // Register server handlers, middlewares, etc.
-func (s *Server) Register(cfg *config.Config) error {
+func (s *Server) Register(cfg *config.Config) error { //nolint:funlen
 	var (
 		liveHandler    = live.New()
 		versionHandler = version.New(appmeta.Version())
@@ -71,7 +71,7 @@ func (s *Server) Register(cfg *config.Config) error {
 
 		switch {
 		// live endpoints
-		case url == "/health/live" || url == "/health" || url == "/healthz" || url == "/live":
+		case url == "/healthz" || url == "/health/live" || url == "/health" || url == "/live":
 			liveHandler(ctx)
 
 		// version endpoint
@@ -87,8 +87,9 @@ func (s *Server) Register(cfg *config.Config) error {
 		//	-	/{code}.html
 		//	- /{code}.htm
 		//	- /{code}
-		case method == fasthttp.MethodGet &&
-			(url == "/" || ep.URLContainsCode(url) || ep.HeadersContainCode(&ctx.Request.Header)):
+		//
+		// the HTTP method is not limited to GET and HEAD - it can be any
+		case url == "/" || ep.URLContainsCode(url) || ep.HeadersContainCode(&ctx.Request.Header):
 			errorPagesHandler(ctx)
 
 		// wrong requests handling

internal/http/server_test.go

@@ -221,6 +221,16 @@ func TestRouting(t *testing.T) {
 				assert.Contains(t, string(body), "404: Not Found")
 				assert.Contains(t, headers.Get("Content-Type"), "text/plain")
 			})
+
+			t.Run("other HTTP methods", func(t *testing.T) {
+				for _, method := range []string{http.MethodDelete, http.MethodPatch, http.MethodPost, http.MethodPut} {
+					var status, body, headers = sendRequest(t, method, baseUrl+"/404.html")
+
+					assert.Equal(t, http.StatusOK, status)
+					assert.Contains(t, string(body), "404: Not Found")
+					assert.Contains(t, headers.Get("Content-Type"), "text/plain")
+				}
+			})
 		})
 
 		t.Run("failure", func(t *testing.T) {
@@ -264,15 +274,6 @@ func TestRouting(t *testing.T) {
 				assert.Equal(t, http.StatusNotFound, status)
 				assertIsNotErrorPage(t, body)
 			})
-
-			t.Run("invalid HTTP methods", func(t *testing.T) {
-				for _, method := range []string{http.MethodDelete, http.MethodPatch, http.MethodPost, http.MethodPut} {
-					var status, body, _ = sendRequest(t, method, baseUrl+"/404.html")
-
-					assert.Equal(t, http.StatusMethodNotAllowed, status)
-					assertIsNotErrorPage(t, body)
-				}
-			})
 		})
 	})
 

internal/template/minify.go

@@ -0,0 +1,23 @@
+package template
+
+import (
+	"github.com/tdewolff/minify/v2"
+	"github.com/tdewolff/minify/v2/css"
+	"github.com/tdewolff/minify/v2/html"
+	"github.com/tdewolff/minify/v2/js"
+	"github.com/tdewolff/minify/v2/svg"
+)
+
+var htmlMinify = func() *minify.M { //nolint:gochecknoglobals
+	var m = minify.New()
+
+	m.AddFunc("text/css", css.Minify)
+	m.Add("text/html", &html.Minifier{KeepDocumentTags: true, KeepEndTags: true, KeepQuotes: true})
+	m.AddFunc("image/svg+xml", svg.Minify)
+	m.AddFunc("application/javascript", js.Minify)
+
+	return m
+}()
+
+// MiniHTML minifies HTML data, including inline CSS, SVG and JS.
+func MiniHTML(data string) (string, error) { return htmlMinify.String("text/html", data) }

internal/template/minify_test.go

@@ -0,0 +1,94 @@
+package template_test
+
+import (
+	"sync"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"gh.tarampamp.am/error-pages/internal/template"
+)
+
+func TestMiniHTML(t *testing.T) {
+	t.Parallel()
+
+	var wg sync.WaitGroup
+
+	for range 100 { // race condition provocation
+		wg.Add(1)
+
+		go func() {
+			defer wg.Done()
+
+			for give, want := range map[string]string{
+				"": "",
+				`<!-- Simple HTML page -->
+<!DOCTYPE html>
+<html>
+<head>
+	<title>Test</title>
+</head>
+<body>
+	<h1 align="center">Test</h1>
+</body>
+</html>`: `<!doctype html><html><head><title>Test</title></head><body><h1 align="center">Test</h1></body></html>`,
+				`<!-- css styles -->
+<html>
+<head>
+	<style>
+		.foo:hover {
+			color: #f0a; /* comment */
+		}
+	</style>
+</head>
+<body>
+	<p style="color: red" class="bar">Text</p>
+</body>
+</html>`: `<html><head><style>.foo:hover{color:#f0a}</style></head><body><p style="color:red" class="bar">Text</p></body></html>`,
+				`<!-- svg -->
+<svg xmlns="http://www.w3.org/2000/svg">
+	<g>
+		<circle cx="50" cy="50" r="40" stroke="black" stroke-width="3" fill="red" />
+	</g>
+</svg>`: `<svg><g><circle cx="50" cy="50" r="40" stroke="#000" stroke-width="3" fill="red"/></g></svg>`,
+				`<!-- js -->
+<html>
+<body>
+<script>
+	// comment
+	console.log('Hello, World!');
+
+	let foo = 1;
+	foo++;
+</script>
+</body>
+</html>`: `<html><body><script>console.log("Hello, World!");let foo=1;foo++</script></body></html>`,
+				`<!-- js module not changed -->
+<html>
+<body>
+<script type="module">
+	// comment
+	console.log('Hello, World!');
+
+	let foo = 1;
+	foo++;
+</script>
+</body>
+</html>`: `<html><body><script type="module">
+	// comment
+	console.log('Hello, World!');
+
+	let foo = 1;
+	foo++;
+</script></body></html>`,
+			} {
+				var got, err = template.MiniHTML(give)
+
+				assert.NoError(t, err)
+				assert.Equal(t, want, got)
+			}
+		}()
+	}
+
+	wg.Wait()
+}