feature: support IN query clauses for nested JSON columns (#272)

* feat: support IN for JSONArrayQuery

* chore: restrict json in for other dialects

* chore: use builder.WriteQuoted for JSON_EXTRACT

* fix: remove superfluous quoted

* fix: allow in query for nested values only

* fix: resolve JSON type and IN operator incompatibility with older MySQL versions

* feat: support in queries for non-nested columns as well

Author: jiazheng2

json.go

@@ -450,39 +450,73 @@ func JSONArrayQuery(column string) *JSONArrayExpression {
 }
 
 type JSONArrayExpression struct {
+	contains    bool
+	in          bool
 	column      string
 	keys        []string
 	equalsValue interface{}
 }
 
-// Contains checks if the column[keys] has contains the value given. The keys parameter is only supported for MySQL.
+// Contains checks if the column[keys] contains the value given. The keys parameter is only supported for MySQL.
 func (json *JSONArrayExpression) Contains(value interface{}, keys ...string) *JSONArrayExpression {
+	json.contains = true
 	json.equalsValue = value
 	json.keys = keys
 	return json
 }
 
+// In checks if columns[keys] is in the array value given. This method is only supported for MySQL.
+func (json *JSONArrayExpression) In(value interface{}, keys ...string) *JSONArrayExpression {
+	json.in = true
+	json.keys = keys
+	json.equalsValue = value
+	return json
+}
+
 // Build implements clause.Expression
 func (json *JSONArrayExpression) Build(builder clause.Builder) {
 	if stmt, ok := builder.(*gorm.Statement); ok {
 		switch stmt.Dialector.Name() {
 		case "mysql":
-			builder.WriteString("JSON_CONTAINS(" + stmt.Quote(json.column) + ",JSON_ARRAY(")
-			builder.AddVar(stmt, json.equalsValue)
-			builder.WriteByte(')')
-			if len(json.keys) > 0 {
+			switch {
+			case json.contains:
+				builder.WriteString("JSON_CONTAINS(" + stmt.Quote(json.column) + ",JSON_ARRAY(")
+				builder.AddVar(stmt, json.equalsValue)
+				builder.WriteByte(')')
+				if len(json.keys) > 0 {
+					builder.WriteByte(',')
+					builder.AddVar(stmt, jsonQueryJoin(json.keys))
+				}
+				builder.WriteByte(')')
+			case json.in:
+				builder.WriteString("JSON_CONTAINS(JSON_ARRAY")
+				builder.AddVar(stmt, json.equalsValue)
 				builder.WriteByte(',')
-				builder.AddVar(stmt, jsonQueryJoin(json.keys))
+				if len(json.keys) > 0 {
+					builder.WriteString("JSON_EXTRACT(")
+				}
+				builder.WriteQuoted(json.column)
+				if len(json.keys) > 0 {
+					builder.WriteByte(',')
+					builder.AddVar(stmt, jsonQueryJoin(json.keys))
+					builder.WriteByte(')')
+				}
+				builder.WriteByte(')')
 			}
-			builder.WriteByte(')')
 		case "sqlite":
-			builder.WriteString("exists(SELECT 1 FROM json_each(" + stmt.Quote(json.column) + ") WHERE value = ")
-			builder.AddVar(stmt, json.equalsValue)
-			builder.WriteString(")")
+			switch {
+			case json.contains:
+				builder.WriteString("exists(SELECT 1 FROM json_each(" + stmt.Quote(json.column) + ") WHERE value = ")
+				builder.AddVar(stmt, json.equalsValue)
+				builder.WriteString(")")
+			}
 		case "postgres":
-			builder.WriteString(stmt.Quote(json.column))
-			builder.WriteString(" ? ")
-			builder.AddVar(stmt, json.equalsValue)
+			switch {
+			case json.contains:
+				builder.WriteString(stmt.Quote(json.column))
+				builder.WriteString(" ? ")
+				builder.AddVar(stmt, json.equalsValue)
+			}
 		}
 	}
 }

json_test.go

@@ -463,7 +463,6 @@ func TestJSONArrayQuery(t *testing.T) {
 			DisplayName: "JSONArray-1",
 			Config:      datatypes.JSON("[\"a\", \"b\"]"),
 		}
-
 		cmp2 := Param{
 			DisplayName: "JSONArray-2",
 			Config:      datatypes.JSON("[\"c\", \"a\"]"),
@@ -472,6 +471,10 @@ func TestJSONArrayQuery(t *testing.T) {
 			DisplayName: "JSONArray-3",
 			Config:      datatypes.JSON("{\"test\": [\"a\", \"b\"]}"),
 		}
+		cmp4 := Param{
+			DisplayName: "JSONArray-4",
+			Config:      datatypes.JSON("{\"test\": \"c\"}"),
+		}
 
 		if err := DB.Create(&cmp1).Error; err != nil {
 			t.Errorf("Failed to create param %v", err)
@@ -482,6 +485,9 @@ func TestJSONArrayQuery(t *testing.T) {
 		if err := DB.Create(&cmp3).Error; err != nil {
 			t.Errorf("Failed to create param %v", err)
 		}
+		if err := DB.Create(&cmp4).Error; err != nil {
+			t.Errorf("Failed to create param %v", err)
+		}
 
 		var retSingle1 Param
 		if err := DB.Where("id = ?", cmp2.ID).First(&retSingle1).Error; err != nil {
@@ -507,5 +513,15 @@ func TestJSONArrayQuery(t *testing.T) {
 			t.Fatalf("failed to find params with json value and keys, got error %v", err)
 		}
 		AssertEqual(t, len(retMultiple), 1)
+
+		if err := DB.Where(datatypes.JSONArrayQuery("config").In([]string{"c", "a"})).Find(&retMultiple).Error; err != nil {
+			t.Fatalf("failed to find params with json value, got error %v", err)
+		}
+		AssertEqual(t, len(retMultiple), 1)
+
+		if err := DB.Where(datatypes.JSONArrayQuery("config").In([]string{"c", "d"}, "test")).Find(&retMultiple).Error; err != nil {
+			t.Fatalf("failed to find params with json value and keys, got error %v", err)
+		}
+		AssertEqual(t, len(retMultiple), 1)
 	}
 }