Allow map[string]interface{} instead struct in query and mutation #80

Author: grihabor

query.go

@@ -3,7 +3,9 @@ package graphql
 import (
 	"bytes"
 	"encoding/json"
+	"fmt"
 	"io"
+	"os"
 	"reflect"
 	"sort"
 
@@ -88,16 +90,23 @@ func writeArgumentType(w io.Writer, t reflect.Type, value bool) {
 // E.g., struct{Foo Int, BarBaz *Boolean} -> "{foo,barBaz}".
 func query(v interface{}) string {
 	var buf bytes.Buffer
-	writeQuery(&buf, reflect.TypeOf(v), false)
+	writeQuery(&buf, reflect.TypeOf(v), reflect.ValueOf(v), false)
 	return buf.String()
 }
 
+var Debug = false
+
 // writeQuery writes a minified query for t to w.
 // If inline is true, the struct fields of t are inlined into parent struct.
-func writeQuery(w io.Writer, t reflect.Type, inline bool) {
+func writeQuery(w io.Writer, t reflect.Type, v reflect.Value, inline bool) {
+	if Debug {
+		_, _ = fmt.Fprintf(os.Stderr, "%v\n%v\n\n", t, TypeSafe(v))
+	}
 	switch t.Kind() {
-	case reflect.Ptr, reflect.Slice:
-		writeQuery(w, t.Elem(), false)
+	case reflect.Ptr:
+		writeQuery(w, t.Elem(), ElemSafe(v), false)
+	case reflect.Slice:
+		writeQuery(w, t.Elem(), IndexSafe(v, 0), false)
 	case reflect.Struct:
 		// If the type implements json.Unmarshaler, it's a scalar. Don't expand it.
 		if reflect.PtrTo(t).Implements(jsonUnmarshaler) {
@@ -120,12 +129,51 @@ func writeQuery(w io.Writer, t reflect.Type, inline bool) {
 					io.WriteString(w, ident.ParseMixedCaps(f.Name).ToLowerCamelCase())
 				}
 			}
-			writeQuery(w, f.Type, inlineField)
+			writeQuery(w, f.Type, FieldSafe(v, i), inlineField)
 		}
 		if !inline {
 			io.WriteString(w, "}")
 		}
+	case reflect.Map: // handle map[string]interface{}
+		it := v.MapRange()
+		_, _ = io.WriteString(w, "{")
+		for it.Next() {
+			// it.Value() returns interface{}, so we need to use reflect.ValueOf
+			// to cast it away
+			key, val := it.Key(), reflect.ValueOf(it.Value().Interface())
+			_, _ = io.WriteString(w, key.String())
+			writeQuery(w, val.Type(), val, false)
+		}
+		_, _ = io.WriteString(w, "}")
+	}
+}
+
+func IndexSafe(v reflect.Value, i int) reflect.Value {
+	if v.IsValid() && i < v.Len() {
+		return v.Index(i)
+	}
+	return reflect.ValueOf(nil)
+}
+
+func TypeSafe(v reflect.Value) reflect.Type {
+	if v.IsValid() {
+		return v.Type()
+	}
+	return reflect.TypeOf((interface{})(nil))
+}
+
+func ElemSafe(v reflect.Value) reflect.Value {
+	if v.IsValid() {
+		return v.Elem()
+	}
+	return reflect.ValueOf(nil)
+}
+
+func FieldSafe(valStruct reflect.Value, i int) reflect.Value {
+	if valStruct.IsValid() {
+		return valStruct.Field(i)
 	}
+	return reflect.ValueOf(nil)
 }
 
 var jsonUnmarshaler = reflect.TypeOf((*json.Unmarshaler)(nil)).Elem()

query_test.go

@@ -188,6 +188,65 @@ func TestConstructQuery(t *testing.T) {
 			},
 			want: `query($issueNumber:Int!$repositoryName:String!$repositoryOwner:String!){repository(owner: $repositoryOwner, name: $repositoryName){issue(number: $issueNumber){reactionGroups{users(first:10){nodes{login}}}}}}`,
 		},
+		// check same thing with repository inner map work
+		{
+			inV: func() interface{} {
+				type query struct {
+					Repository map[string]interface{} `graphql:"repository(owner: $repositoryOwner, name: $repositoryName)"`
+				}
+				type issue struct {
+					ReactionGroups []struct {
+						Users struct {
+							Nodes []struct {
+								Login String
+							}
+						} `graphql:"users(first:10)"`
+					}
+				}
+				return query{Repository: map[string]interface{}{
+					"issue(number: $issueNumber)": issue{},
+				}}
+			}(),
+			inVariables: map[string]interface{}{
+				"repositoryOwner": String("shurcooL-test"),
+				"repositoryName":  String("test-repo"),
+				"issueNumber":     Int(1),
+			},
+			want: `query($issueNumber:Int!$repositoryName:String!$repositoryOwner:String!){repository(owner: $repositoryOwner, name: $repositoryName){issue(number: $issueNumber){reactionGroups{users(first:10){nodes{login}}}}}}`,
+		},
+		// check inner maps work inside slices
+		{
+			inV: func() interface{} {
+				type query struct {
+					Repository map[string]interface{} `graphql:"repository(owner: $repositoryOwner, name: $repositoryName)"`
+				}
+				type issue struct {
+					ReactionGroups []struct {
+						Users map[string]interface{} `graphql:"users(first:10)"`
+					}
+				}
+				type nodes []struct {
+					Login String
+				}
+				return query{Repository: map[string]interface{}{
+					"issue(number: $issueNumber)": issue{
+						ReactionGroups: []struct {
+							Users map[string]interface{} `graphql:"users(first:10)"`
+						}{
+							{Users: map[string]interface{}{
+								"nodes": nodes{},
+							}},
+						},
+					},
+				}}
+			}(),
+			inVariables: map[string]interface{}{
+				"repositoryOwner": String("shurcooL-test"),
+				"repositoryName":  String("test-repo"),
+				"issueNumber":     Int(1),
+			},
+			want: `query($issueNumber:Int!$repositoryName:String!$repositoryOwner:String!){repository(owner: $repositoryOwner, name: $repositoryName){issue(number: $issueNumber){reactionGroups{users(first:10){nodes{login}}}}}}`,
+		},
 		// Embedded structs without graphql tag should be inlined in query.
 		{
 			inV: func() interface{} {
@@ -236,6 +295,14 @@ func TestConstructQuery(t *testing.T) {
 	}
 }
 
+type CreateUser struct {
+	Login string
+}
+
+type DeleteUser struct {
+	Login string
+}
+
 func TestConstructMutation(t *testing.T) {
 	tests := []struct {
 		inV         interface{}
@@ -262,6 +329,17 @@ func TestConstructMutation(t *testing.T) {
 			},
 			want: `mutation($input:AddReactionInput!){addReaction(input:$input){subject{reactionGroups{users{totalCount}}}}}`,
 		},
+		{
+			inV: map[string]interface{}{
+				"createUser(login:$login1)": &CreateUser{},
+				"deleteUser(login:$login2)": &DeleteUser{},
+			},
+			inVariables: map[string]interface{}{
+				"login1": String("grihabor"),
+				"login2": String("diman"),
+			},
+			want: "mutation($login1:String!$login2:String!){createUser(login:$login1){login}deleteUser(login:$login2){login}}",
+		},
 	}
 	for _, tc := range tests {
 		got := constructMutation(tc.inV, tc.inVariables)