feat: publish sanitized custom.97 source

middleware/frontend_static_test.go

@@ -0,0 +1,106 @@
+package middleware
+
+import (
+	"bytes"
+	"compress/gzip"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+	"sync"
+	"sync/atomic"
+	"testing"
+
+	"github.com/gin-contrib/static"
+	"github.com/gin-gonic/gin"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+type countingFrontendFS struct {
+	static.ServeFileSystem
+	opens atomic.Int32
+}
+
+func (f *countingFrontendFS) Open(name string) (http.File, error) {
+	f.opens.Add(1)
+	return f.ServeFileSystem.Open(name)
+}
+
+func performFrontendRequest(router http.Handler, method, target, acceptEncoding string) *httptest.ResponseRecorder {
+	recorder := httptest.NewRecorder()
+	request := httptest.NewRequest(method, target, nil)
+	if acceptEncoding != "" {
+		request.Header.Set("Accept-Encoding", acceptEncoding)
+	}
+	router.ServeHTTP(recorder, request)
+	return recorder
+}
+
+func TestServeFrontendFilesCompressesEachFileOnce(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+	frontendDir := t.TempDir()
+	script := []byte(strings.Repeat("export const answer = 42;\n", 400))
+	image := []byte("\x89PNG\r\n\x1a\nnot-really-an-image")
+	require.NoError(t, os.MkdirAll(filepath.Join(frontendDir, "static", "js"), 0o755))
+	require.NoError(t, os.WriteFile(filepath.Join(frontendDir, "static", "js", "app.js"), script, 0o644))
+	require.NoError(t, os.WriteFile(filepath.Join(frontendDir, "logo.png"), image, 0o644))
+	require.NoError(t, os.WriteFile(filepath.Join(frontendDir, "index.html"), []byte("<html></html>"), 0o644))
+	frontendFS := &countingFrontendFS{ServeFileSystem: static.LocalFile(frontendDir, false)}
+
+	router := gin.New()
+	router.NoRoute(ServeFrontendFiles(frontendFS), func(c *gin.Context) {
+		c.String(http.StatusTeapot, "fallback")
+	})
+
+	plain := performFrontendRequest(router, http.MethodGet, "/static/js/app.js", "")
+	require.Equal(t, http.StatusOK, plain.Code)
+	assert.Empty(t, plain.Header().Get("Content-Encoding"))
+	assert.Equal(t, script, plain.Body.Bytes())
+	frontendFS.opens.Store(0)
+
+	responses := make([]*httptest.ResponseRecorder, 8)
+	var wg sync.WaitGroup
+	for i := range responses {
+		wg.Go(func() {
+			responses[i] = performFrontendRequest(router, http.MethodGet, "/static/js/app.js", "gzip, deflate, br")
+		})
+	}
+	wg.Wait()
+	for _, response := range responses {
+		require.Equal(t, http.StatusOK, response.Code)
+		assert.Equal(t, "gzip", response.Header().Get("Content-Encoding"))
+		assert.Equal(t, "Accept-Encoding", response.Header().Get("Vary"))
+		assert.Equal(t, plain.Header().Get("Content-Type"), response.Header().Get("Content-Type"))
+		assert.Equal(t, strconv.Itoa(response.Body.Len()), response.Header().Get("Content-Length"))
+		assert.Equal(t, responses[0].Body.Bytes(), response.Body.Bytes())
+	}
+	reader, err := gzip.NewReader(bytes.NewReader(responses[0].Body.Bytes()))
+	require.NoError(t, err)
+	decoded, err := io.ReadAll(reader)
+	require.NoError(t, err)
+	assert.Equal(t, script, decoded)
+
+	head := performFrontendRequest(router, http.MethodHead, "/static/js/app.js", "gzip")
+	assert.Equal(t, http.StatusOK, head.Code)
+	assert.Equal(t, "gzip", head.Header().Get("Content-Encoding"))
+	assert.Equal(t, strconv.Itoa(responses[0].Body.Len()), head.Header().Get("Content-Length"))
+	assert.Empty(t, head.Body.Bytes())
+	assert.Equal(t, int32(1), frontendFS.opens.Load(), "the file must be read and compressed once")
+
+	png := performFrontendRequest(router, http.MethodGet, "/logo.png", "gzip")
+	assert.Equal(t, http.StatusOK, png.Code)
+	assert.Empty(t, png.Header().Get("Content-Encoding"))
+	assert.Equal(t, image, png.Body.Bytes())
+
+	index := performFrontendRequest(router, http.MethodGet, "/index.html", "gzip")
+	assert.Equal(t, http.StatusMovedPermanently, index.Code)
+	assert.Equal(t, "./", index.Header().Get("Location"))
+
+	missing := performFrontendRequest(router, http.MethodGet, "/static/js/missing.js", "gzip")
+	assert.Equal(t, http.StatusTeapot, missing.Code)
+	assert.Equal(t, "fallback", missing.Body.String())
+}