From 2340f7a7ae54c33e5d065d99a1f30906f64ba229 Mon Sep 17 00:00:00 2001
From: Adam <adam@vektah.net>
Date: Tue, 18 Feb 2020 14:50:02 +1100
Subject: [PATCH] Ensure panic handlers get applied

---
 codegen/testserver/panics_test.go | 26 +++++++++++++++++++++-----
 graphql/handler/executor.go       |  2 +-
 graphql/recovery.go               | 20 --------------------
 3 files changed, 22 insertions(+), 26 deletions(-)

diff --git a/codegen/testserver/panics_test.go b/codegen/testserver/panics_test.go
index 85235864f0a..68903391496 100644
--- a/codegen/testserver/panics_test.go
+++ b/codegen/testserver/panics_test.go
@@ -2,11 +2,15 @@ package testserver
 
 import (
 	"context"
+	"fmt"
 	"testing"
 
+	"github.com/99designs/gqlgen/graphql"
+
 	"github.com/99designs/gqlgen/client"
 	"github.com/99designs/gqlgen/graphql/handler"
 	"github.com/stretchr/testify/require"
+	"github.com/vektah/gqlparser/v2/gqlerror"
 )
 
 func TestPanics(t *testing.T) {
@@ -21,33 +25,45 @@ func TestPanics(t *testing.T) {
 		return []MarshalPanic{MarshalPanic("aa"), MarshalPanic("bb")}, nil
 	}
 
-	c := client.New(handler.NewDefaultServer(NewExecutableSchema(Config{Resolvers: resolvers})))
+	srv := handler.NewDefaultServer(NewExecutableSchema(Config{Resolvers: resolvers}))
+	srv.SetRecoverFunc(func(ctx context.Context, err interface{}) (userMessage error) {
+		return fmt.Errorf("panic: %v", err)
+	})
+
+	srv.SetErrorPresenter(func(ctx context.Context, err error) *gqlerror.Error {
+		return &gqlerror.Error{
+			Message: "presented: " + err.Error(),
+			Path:    graphql.GetFieldContext(ctx).Path(),
+		}
+	})
+
+	c := client.New(srv)
 
 	t.Run("panics in marshallers will not kill server", func(t *testing.T) {
 		var resp interface{}
 		err := c.Post(`query { panics { fieldScalarMarshal } }`, &resp)
 
-		require.EqualError(t, err, "http 422: {\"errors\":[{\"message\":\"internal system error\"}],\"data\":null}")
+		require.EqualError(t, err, "http 422: {\"errors\":[{\"message\":\"presented: panic: BOOM\"}],\"data\":null}")
 	})
 
 	t.Run("panics in unmarshalers will not kill server", func(t *testing.T) {
 		var resp interface{}
 		err := c.Post(`query { panics { argUnmarshal(u: ["aa", "bb"]) } }`, &resp)
 
-		require.EqualError(t, err, "[{\"message\":\"internal system error\",\"path\":[\"panics\",\"argUnmarshal\"]}]")
+		require.EqualError(t, err, "[{\"message\":\"presented: panic: BOOM\",\"path\":[\"panics\",\"argUnmarshal\"]}]")
 	})
 
 	t.Run("panics in funcs unmarshal return errors", func(t *testing.T) {
 		var resp interface{}
 		err := c.Post(`query { panics { fieldFuncMarshal(u: ["aa", "bb"]) } }`, &resp)
 
-		require.EqualError(t, err, "[{\"message\":\"internal system error\",\"path\":[\"panics\",\"fieldFuncMarshal\"]}]")
+		require.EqualError(t, err, "[{\"message\":\"presented: panic: BOOM\",\"path\":[\"panics\",\"fieldFuncMarshal\"]}]")
 	})
 
 	t.Run("panics in funcs marshal return errors", func(t *testing.T) {
 		var resp interface{}
 		err := c.Post(`query { panics { fieldFuncMarshal(u: []) } }`, &resp)
 
-		require.EqualError(t, err, "http 422: {\"errors\":[{\"message\":\"internal system error\"}],\"data\":null}")
+		require.EqualError(t, err, "http 422: {\"errors\":[{\"message\":\"presented: panic: BOOM\"}],\"data\":null}")
 	})
 }
diff --git a/graphql/handler/executor.go b/graphql/handler/executor.go
index 394d3f5619b..61593f7553c 100644
--- a/graphql/handler/executor.go
+++ b/graphql/handler/executor.go
@@ -119,7 +119,7 @@ func (e executor) DispatchOperation(ctx context.Context, rc *graphql.OperationCo
 func (e executor) CreateOperationContext(ctx context.Context, params *graphql.RawParams) (*graphql.OperationContext, gqlerror.List) {
 	rc := &graphql.OperationContext{
 		DisableIntrospection: true,
-		Recover:              graphql.DefaultRecover,
+		Recover:              e.server.recoverFunc,
 		ResolverMiddleware:   e.fieldMiddleware,
 		Stats: graphql.Stats{
 			Read:           params.ReadTime,
diff --git a/graphql/recovery.go b/graphql/recovery.go
index 5c3c1027eb0..3aa032dc5aa 100644
--- a/graphql/recovery.go
+++ b/graphql/recovery.go
@@ -6,8 +6,6 @@ import (
 	"fmt"
 	"os"
 	"runtime/debug"
-
-	"github.com/vektah/gqlparser/v2/gqlerror"
 )
 
 type RecoverFunc func(ctx context.Context, err interface{}) (userMessage error)
@@ -19,21 +17,3 @@ func DefaultRecover(ctx context.Context, err interface{}) error {
 
 	return errors.New("internal system error")
 }
-
-var _ OperationContextMutator = RecoverFunc(nil)
-
-func (f RecoverFunc) ExtensionName() string {
-	return "RecoverFunc"
-}
-
-func (f RecoverFunc) Validate(schema ExecutableSchema) error {
-	if f == nil {
-		return fmt.Errorf("RecoverFunc can not be nil")
-	}
-	return nil
-}
-
-func (f RecoverFunc) MutateOperationContext(ctx context.Context, rc *OperationContext) *gqlerror.Error {
-	rc.Recover = f
-	return nil
-}