add a new 'Context.GzipReader(bool) method and 'iris.GzipReader' middleware as requested at #1528

Former-commit-id: 7665545069bf1784d17a9db1e5f9f5f8df4b0c43

_examples/http_request/read-gzip/main_test.go

@@ -0,0 +1,38 @@
+package main
+
+import (
+	"bytes"
+	"compress/gzip"
+	"encoding/json"
+	"testing"
+
+	"github.com/kataras/iris/v12/httptest"
+)
+
+func TestGzipReader(t *testing.T) {
+	app := newApp()
+
+	expected := payload{Message: "test"}
+	b, err := json.Marshal(expected)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	buf := new(bytes.Buffer)
+	w := gzip.NewWriter(buf)
+	_, err = w.Write(b)
+	if err != nil {
+		t.Fatal(err)
+	}
+	err = w.Close()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	e := httptest.New(t, app)
+	// send gzip compressed.
+	e.POST("/").WithHeader("Content-Encoding", "gzip").WithHeader("Content-Type", "application/json").
+		WithBytes(buf.Bytes()).Expect().Status(httptest.StatusOK).Body().Equal(expected.Message)
+	// raw.
+	e.POST("/").WithJSON(expected).Expect().Status(httptest.StatusOK).Body().Equal(expected.Message)
+}