[chore]: Bump github.com/gin-contrib/gzip from 1.1.0 to 1.2.2 (#3693)

Bumps [github.com/gin-contrib/gzip](https://github.com/gin-contrib/gzip) from 1.1.0 to 1.2.2.
- [Release notes](https://github.com/gin-contrib/gzip/releases)
- [Changelog](https://github.com/gin-contrib/gzip/blob/master/.goreleaser.yaml)
- [Commits](https://github.com/gin-contrib/gzip/compare/v1.1.0...v1.2.2)

---
updated-dependencies:
- dependency-name: github.com/gin-contrib/gzip
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

vendor/github.com/gin-contrib/gzip/handler.go

@@ -2,84 +2,114 @@ package gzip
 
 import (
 	"compress/gzip"
-	"fmt"
 	"io"
 	"net/http"
 	"path/filepath"
+	"strconv"
 	"strings"
 	"sync"
 
 	"github.com/gin-gonic/gin"
 )
 
+const (
+	headerAcceptEncoding  = "Accept-Encoding"
+	headerContentEncoding = "Content-Encoding"
+	headerVary            = "Vary"
+)
+
 type gzipHandler struct {
-	*Options
+	*config
 	gzPool sync.Pool
 }
 
-func newGzipHandler(level int, options ...Option) *gzipHandler {
+func isCompressionLevelValid(level int) bool {
+	return level == gzip.DefaultCompression ||
+		level == gzip.NoCompression ||
+		(level >= gzip.BestSpeed && level <= gzip.BestCompression)
+}
+
+func newGzipHandler(level int, opts ...Option) *gzipHandler {
+	cfg := &config{
+		excludedExtensions: DefaultExcludedExtentions,
+	}
+
+	// Apply each option to the config
+	for _, o := range opts {
+		o.apply(cfg)
+	}
+
+	if !isCompressionLevelValid(level) {
+		// For web content, level 4 seems to be a sweet spot.
+		level = 4
+	}
+
 	handler := &gzipHandler{
-		Options: DefaultOptions,
+		config: cfg,
 		gzPool: sync.Pool{
 			New: func() interface{} {
-				gz, err := gzip.NewWriterLevel(io.Discard, level)
-				if err != nil {
-					panic(err)
-				}
+				gz, _ := gzip.NewWriterLevel(io.Discard, level)
 				return gz
 			},
 		},
 	}
-	for _, setter := range options {
-		setter(handler.Options)
-	}
 	return handler
 }
 
+// Handle is a middleware function for handling gzip compression in HTTP requests and responses.
+// It first checks if the request has a "Content-Encoding" header set to "gzip" and if a decompression
+// function is provided, it will call the decompression function. If the handler is set to decompress only,
+// or if the custom compression decision function indicates not to compress, it will return early.
+// Otherwise, it retrieves a gzip.Writer from the pool, sets the necessary response headers for gzip encoding,
+// and wraps the response writer with a gzipWriter. After the request is processed, it ensures the gzip.Writer
+// is properly closed and the "Content-Length" header is set based on the response size.
 func (g *gzipHandler) Handle(c *gin.Context) {
-	if fn := g.DecompressFn; fn != nil && c.Request.Header.Get("Content-Encoding") == "gzip" {
+	if fn := g.decompressFn; fn != nil && strings.Contains(c.Request.Header.Get("Content-Encoding"), "gzip") {
 		fn(c)
 	}
 
-	if !g.shouldCompress(c.Request) {
+	if g.decompressOnly ||
+		(g.customShouldCompressFn != nil && !g.customShouldCompressFn(c)) ||
+		(g.customShouldCompressFn == nil && !g.shouldCompress(c.Request)) {
 		return
 	}
 
 	gz := g.gzPool.Get().(*gzip.Writer)
-	defer g.gzPool.Put(gz)
-	defer gz.Reset(io.Discard)
 	gz.Reset(c.Writer)
 
-	c.Header("Content-Encoding", "gzip")
-	c.Header("Vary", "Accept-Encoding")
+	c.Header(headerContentEncoding, "gzip")
+	c.Writer.Header().Add(headerVary, headerAcceptEncoding)
+	// check ETag Header
+	originalEtag := c.GetHeader("ETag")
+	if originalEtag != "" && !strings.HasPrefix(originalEtag, "W/") {
+		c.Header("ETag", "W/"+originalEtag)
+	}
 	c.Writer = &gzipWriter{c.Writer, gz}
 	defer func() {
 		if c.Writer.Size() < 0 {
 			// do not write gzip footer when nothing is written to the response body
 			gz.Reset(io.Discard)
 		}
-		gz.Close()
-		c.Header("Content-Length", fmt.Sprint(c.Writer.Size()))
+		_ = gz.Close()
+		if c.Writer.Size() > -1 {
+			c.Header("Content-Length", strconv.Itoa(c.Writer.Size()))
+		}
+		g.gzPool.Put(gz)
 	}()
 	c.Next()
 }
 
 func (g *gzipHandler) shouldCompress(req *http.Request) bool {
-	if !strings.Contains(req.Header.Get("Accept-Encoding"), "gzip") ||
-		strings.Contains(req.Header.Get("Connection"), "Upgrade") ||
-		strings.Contains(req.Header.Get("Accept"), "text/event-stream") {
+	if !strings.Contains(req.Header.Get(headerAcceptEncoding), "gzip") ||
+		strings.Contains(req.Header.Get("Connection"), "Upgrade") {
 		return false
 	}
 
+	// Check if the request path is excluded from compression
 	extension := filepath.Ext(req.URL.Path)
-	if g.ExcludedExtensions.Contains(extension) {
-		return false
-	}
-
-	if g.ExcludedPaths.Contains(req.URL.Path) {
-		return false
-	}
-	if g.ExcludedPathesRegexs.Contains(req.URL.Path) {
+	if g.excludedExtensions.Contains(extension) ||
+		g.excludedPaths.Contains(req.URL.Path) ||
+		g.excludedPathesRegexs.Contains(req.URL.Path) {
 		return false
 	}