Add support for json.RawMessage (from github.com/shurcooL/pull/41)

Author: rideliner

graphql_test.go

@@ -2,6 +2,7 @@ package graphql_test
 
 import (
 	"context"
+	"encoding/json"
 	"io"
 	"io/ioutil"
 	"net/http"
@@ -64,6 +65,55 @@ func TestClient_Query_partialDataWithErrorResponse(t *testing.T) {
 	}
 }
 
+func TestClient_Query_partialDataRawQueryWithErrorResponse(t *testing.T) {
+	mux := http.NewServeMux()
+	mux.HandleFunc("/graphql", func(w http.ResponseWriter, req *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		mustWrite(w, `{
+			"data": {
+				"node1": { "id": "MDEyOklzc3VlQ29tbWVudDE2OTQwNzk0Ng==" },
+				"node2": null
+			},
+			"errors": [
+				{
+					"message": "Could not resolve to a node with the global id of 'NotExist'",
+					"type": "NOT_FOUND",
+					"path": [
+						"node2"
+					],
+					"locations": [
+						{
+							"line": 10,
+							"column": 4
+						}
+					]
+				}
+			]
+		}`)
+	})
+	client := graphql.NewClient("/graphql", &http.Client{Transport: localRoundTripper{handler: mux}})
+
+	var q struct {
+		Node1 json.RawMessage `graphql:"node1"`
+		Node2 *struct {
+			ID graphql.ID
+		} `graphql:"node2: node(id: \"NotExist\")"`
+	}
+	err := client.Query(context.Background(), &q, nil)
+	if err == nil {
+		t.Fatal("got error: nil, want: non-nil\n")
+	}
+	if got, want := err.Error(), "Could not resolve to a node with the global id of 'NotExist'"; got != want {
+		t.Errorf("got error: %v, want: %v\n", got, want)
+	}
+	if q.Node1 == nil || string(q.Node1) != `{"id":"MDEyOklzc3VlQ29tbWVudDE2OTQwNzk0Ng=="}` {
+		t.Errorf("got wrong q.Node1: %v\n", string(q.Node1))
+	}
+	if q.Node2 != nil {
+		t.Errorf("got non-nil q.Node2: %v, want: nil\n", *q.Node2)
+	}
+}
+
 func TestClient_Query_noDataWithErrorResponse(t *testing.T) {
 	mux := http.NewServeMux()
 	mux.HandleFunc("/graphql", func(w http.ResponseWriter, req *http.Request) {

internal/jsonutil/graphql.go

@@ -42,6 +42,7 @@ func UnmarshalGraphQL(data []byte, v interface{}) error {
 type decoder struct {
 	tokenizer interface {
 		Token() (json.Token, error)
+		Decode(v interface{}) error
 	}
 
 	// Stack of what part of input JSON we're in the middle of - objects, arrays.
@@ -68,10 +69,14 @@ func (d *decoder) Decode(v interface{}) error {
 
 // decode decodes a single JSON value from d.tokenizer into d.vs.
 func (d *decoder) decode() error {
+	rawMessageValue := reflect.ValueOf(json.RawMessage{})
+
 	// The loop invariant is that the top of each d.vs stack
 	// is where we try to unmarshal the next JSON value we see.
 	for len(d.vs) > 0 {
+		var tok interface{}
 		tok, err := d.tokenizer.Token()
+
 		if err == io.EOF {
 			return errors.New("unexpected end of JSON input")
 		} else if err != nil {
@@ -87,6 +92,8 @@ func (d *decoder) decode() error {
 				return errors.New("unexpected non-key in JSON input")
 			}
 			someFieldExist := false
+			// If one field is raw all must be treated as raw
+			rawMessage := false
 			for i := range d.vs {
 				v := d.vs[i][len(d.vs[i])-1]
 				if v.Kind() == reflect.Ptr {
@@ -97,6 +104,10 @@ func (d *decoder) decode() error {
 					f = fieldByGraphQLName(v, key)
 					if f.IsValid() {
 						someFieldExist = true
+						// Check for special embedded json
+						if f.Type() == rawMessageValue.Type() {
+							rawMessage = true
+						}
 					}
 				}
 				d.vs[i] = append(d.vs[i], f)
@@ -105,13 +116,20 @@ func (d *decoder) decode() error {
 				return fmt.Errorf("struct field for %q doesn't exist in any of %v places to unmarshal", key, len(d.vs))
 			}
 
-			// We've just consumed the current token, which was the key.
-			// Read the next token, which should be the value, and let the rest of code process it.
-			tok, err = d.tokenizer.Token()
-			if err == io.EOF {
-				return errors.New("unexpected end of JSON input")
-			} else if err != nil {
-				return err
+			if rawMessage {
+				// Read the next complete object from the json stream
+				var data json.RawMessage
+				d.tokenizer.Decode(&data)
+				tok = data
+			} else {
+				// We've just consumed the current token, which was the key.
+				// Read the next token, which should be the value, and let the rest of code process it.
+				tok, err = d.tokenizer.Token()
+				if err == io.EOF {
+					return errors.New("unexpected end of JSON input")
+				} else if err != nil {
+					return err
+				}
 			}
 
 		// Are we inside an array and seeing next value (rather than end of array)?
@@ -136,7 +154,7 @@ func (d *decoder) decode() error {
 		}
 
 		switch tok := tok.(type) {
-		case string, json.Number, bool, nil:
+		case string, json.Number, bool, nil, json.RawMessage:
 			// Value.
 
 			for i := range d.vs {
@@ -302,7 +320,7 @@ func isGraphQLFragment(f reflect.StructField) bool {
 // unmarshalValue unmarshals JSON value into v.
 // v must be addressable and not obtained by the use of unexported
 // struct fields, otherwise unmarshalValue will panic.
-func unmarshalValue(value json.Token, v reflect.Value) error {
+func unmarshalValue(value interface{}, v reflect.Value) error {
 	b, err := json.Marshal(value) // TODO: Short-circuit (if profiling says it's worth it).
 	if err != nil {
 		return err

internal/jsonutil/graphql_test.go

@@ -1,6 +1,7 @@
 package jsonutil_test
 
 import (
+	"encoding/json"
 	"reflect"
 	"testing"
 	"time"
@@ -80,6 +81,29 @@ func TestUnmarshalGraphQL_jsonTag(t *testing.T) {
 	}
 }
 
+func TestUnmarshalGraphQL_jsonRawTag(t *testing.T) {
+	type query struct {
+		Data    json.RawMessage
+		Another string
+	}
+	var got query
+	err := jsonutil.UnmarshalGraphQL([]byte(`{
+		"Data": { "foo":"bar" },
+		"Another" : "stuff"
+        }`), &got)
+
+	if err != nil {
+		t.Fatal(err)
+	}
+	want := query{
+		Another: "stuff",
+		Data:    []byte(`{"foo":"bar"}`),
+	}
+	if !reflect.DeepEqual(got, want) {
+		t.Errorf("not equal: %v %v", want, got)
+	}
+}
+
 func TestUnmarshalGraphQL_array(t *testing.T) {
 	type query struct {
 		Foo []graphql.String