Move code to pkg

pkg/middlewares/compress/compress.go

@@ -0,0 +1,58 @@
+package compress
+
+import (
+	"compress/gzip"
+	"context"
+	"net/http"
+	"strings"
+
+	"github.com/NYTimes/gziphandler"
+	"github.com/containous/traefik/pkg/middlewares"
+	"github.com/containous/traefik/pkg/tracing"
+	"github.com/opentracing/opentracing-go/ext"
+	"github.com/sirupsen/logrus"
+)
+
+const (
+	typeName = "Compress"
+)
+
+// Compress is a middleware that allows to compress the response.
+type compress struct {
+	next http.Handler
+	name string
+}
+
+// New creates a new compress middleware.
+func New(ctx context.Context, next http.Handler, name string) (http.Handler, error) {
+	middlewares.GetLogger(ctx, name, typeName).Debug("Creating middleware")
+
+	return &compress{
+		next: next,
+		name: name,
+	}, nil
+}
+
+func (c *compress) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
+	contentType := req.Header.Get("Content-Type")
+	if strings.HasPrefix(contentType, "application/grpc") {
+		c.next.ServeHTTP(rw, req)
+	} else {
+		gzipHandler(c.next, middlewares.GetLogger(req.Context(), c.name, typeName)).ServeHTTP(rw, req)
+	}
+}
+
+func (c *compress) GetTracingInformation() (string, ext.SpanKindEnum) {
+	return c.name, tracing.SpanKindNoneEnum
+}
+
+func gzipHandler(h http.Handler, logger logrus.FieldLogger) http.Handler {
+	wrapper, err := gziphandler.GzipHandlerWithOpts(
+		gziphandler.CompressionLevel(gzip.DefaultCompression),
+		gziphandler.MinSize(gziphandler.DefaultMinSize))
+	if err != nil {
+		logger.Error(err)
+	}
+
+	return wrapper(h)
+}