fix https://github.com/kataras/iris/issues/1569#issuecomment-663739177

Former-commit-id: c55f1023f4d93f6712c7fa4d299bcf1098872ecf

HISTORY.md

@@ -371,6 +371,8 @@ Other Improvements:
 
 ![DBUG routes](https://iris-go.com/images/v12.2.0-dbug2.png?v=0)
 
+- Fix [#1569#issuecomment-663739177](https://github.com/kataras/iris/issues/1569#issuecomment-663739177).
+
 - Fix [#1564](https://github.com/kataras/iris/issues/1564).
 
 - Fix [#1553](https://github.com/kataras/iris/issues/1553).

_examples/routing/http-errors/reset-body/main.go

@@ -0,0 +1,42 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/kataras/iris/v12"
+)
+
+func main() {
+	app := newApp()
+	app.Listen(":8080")
+}
+
+func newApp() *iris.Application {
+	app := iris.New()
+	app.Use(iris.Compression)
+
+	app.OnAnyErrorCode(onErrorCode)
+	app.Get("/", handler)
+
+	app.Configure(iris.WithResetOnFireErrorCode)
+	return app
+}
+
+// This is the default error handler Iris uses for any error codes.
+func onErrorCode(ctx iris.Context) {
+	if err := ctx.GetErr(); err != nil {
+		ctx.WriteString(err.Error())
+	} else {
+		ctx.WriteString(iris.StatusText(ctx.GetStatusCode()))
+	}
+}
+
+func handler(ctx iris.Context) {
+	ctx.Record()
+
+	ctx.WriteString("This should NOT be written")
+
+	// [....something bad happened after we "write"]
+	err := fmt.Errorf("custom error")
+	ctx.StopWithError(iris.StatusBadRequest, err)
+}

_examples/routing/http-errors/reset-body/main_test.go

@@ -0,0 +1,14 @@
+package main
+
+import (
+	"testing"
+
+	"github.com/kataras/iris/v12/httptest"
+)
+
+func TestResetCompressionAndFireError(t *testing.T) { // #1569
+	app := newApp()
+
+	e := httptest.New(t, app)
+	e.GET("/").Expect().Status(httptest.StatusBadRequest).Body().Equal("custom error")
+}

context/context.go

@@ -600,6 +600,7 @@ func (ctx *Context) StopWithText(statusCode int, plainText string) {
 
 // StopWithError stops the handlers chain and writes the "statusCode"
 // among with the error "err".
+// It Calls the `SetErr` method so error handlers can access the given error.
 //
 // If the status code is a failure one then
 // it will also fire the specified error code handler.
@@ -608,6 +609,7 @@ func (ctx *Context) StopWithError(statusCode int, err error) {
 		return
 	}
 
+	ctx.SetErr(err)
 	ctx.StopWithText(statusCode, err.Error())
 }
 
@@ -4255,7 +4257,9 @@ func (ctx *Context) MaxAge() int64 {
 // which can be used to reset the body, reset headers, get the body,
 // get & set the status code at any time and more.
 func (ctx *Context) Record() {
-	if w, ok := ctx.writer.(*responseWriter); ok {
+	switch w := ctx.writer.(type) {
+	case *ResponseRecorder:
+	default:
 		recorder := AcquireResponseRecorder()
 		recorder.BeginRecord(w)
 		ctx.ResetResponseWriter(recorder)

core/router/handler.go

@@ -473,6 +473,11 @@ func (h *routerHandler) FireErrorCode(ctx *context.Context) {
 			// reset if previous content and it's recorder, keep the status code.
 			w.ClearHeaders()
 			w.ResetBody()
+
+			if cw, ok := w.ResponseWriter.(*context.CompressResponseWriter); ok {
+				// recorder wraps a compress writer.
+				cw.Disabled = true
+			}
 		} else if w, ok := ctx.ResponseWriter().(*context.CompressResponseWriter); ok {
 			// reset and disable the gzip in order to be an expected form of http error result
 			w.Disabled = true