feat: Add import reader for json

internal/storage/insert_data.go

@@ -78,13 +78,12 @@
 	if i.Data == nil || len(i.Data) == 0 {
 		return 0
 	}
-
-	data, ok := i.Data[common.RowIDField]
-	if !ok {
-		return 0
+	var rowNum int
+	for _, data := range i.Data {
+		rowNum = data.RowNum()
+		break
 	}
-
-	return data.RowNum()
+	return rowNum
 }
 
 func (i *InsertData) GetMemorySize() int {
@@ -115,6 +114,14 @@
 	return nil
 }
 
+func (i *InsertData) GetRow(idx int) map[FieldID]interface{} {
+	res := make(map[FieldID]interface{})
+	for field, data := range i.Data {
+		res[field] = data.GetRow(idx)
+	}
+	return res
+}
+
 // FieldData defines field data interface
 type FieldData interface {
 	GetMemorySize() int

internal/util/importutilv2/json/reader.go

@@ -0,0 +1,143 @@
+// Licensed to the LF AI & Data foundation under one
+// or more contributor license agreements. See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership. The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License. You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package json
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"strings"
+
+	"github.com/milvus-io/milvus-proto/go-api/v2/schemapb"
+	"github.com/milvus-io/milvus/internal/storage"
+	"github.com/milvus-io/milvus/pkg/util/merr"
+)
+
+const (
+	RowRootNode = "rows"
+)
+
+type Row = map[storage.FieldID]any
+
+type reader struct {
+	dec    *json.Decoder
+	schema *schemapb.CollectionSchema
+
+	bufferSize  int
+	isOldFormat bool
+
+	parser RowParser
+}
+
+func NewReader(r io.Reader, schema *schemapb.CollectionSchema, bufferSize int) (*reader, error) {
+	reader := &reader{
+		dec:        json.NewDecoder(r),
+		schema:     schema,
+		bufferSize: bufferSize,
+	}
+	var err error
+	reader.parser, err = NewRowParser(schema)
+	if err != nil {
+		return nil, err
+	}
+	err = reader.Init()
+	if err != nil {
+		return nil, err
+	}
+	return reader, nil
+}
+
+func (j *reader) Init() error {
+	// Treat number value as a string instead of a float64.
+	// By default, json lib treat all number values as float64,
+	// but if an int64 value has more than 15 digits,
+	// the value would be incorrect after converting from float64.
+	j.dec.UseNumber()
+	t, err := j.dec.Token()
+	if err != nil {
+		return merr.WrapErrImportFailed(fmt.Sprintf("failed to decode JSON, error: %v", err))
+	}
+	if t != json.Delim('{') && t != json.Delim('[') {
+		return merr.WrapErrImportFailed("invalid JSON format, the content should be started with '{' or '['")
+	}
+	j.isOldFormat = t == json.Delim('{')
+	return nil
+}
+
+func (j *reader) Read() (*storage.InsertData, error) {
+	insertData, err := storage.NewInsertData(j.schema)
+	if err != nil {
+		return nil, err
+	}
+	if !j.dec.More() {
+		return nil, nil
+	}
+	if j.isOldFormat {
+		// read the key
+		t, err := j.dec.Token()
+		if err != nil {
+			return nil, merr.WrapErrImportFailed(fmt.Sprintf("failed to decode the JSON file, error: %v", err))
+		}
+		key := t.(string)
+		keyLower := strings.ToLower(key)
+		// the root key should be RowRootNode
+		if keyLower != RowRootNode {
+			return nil, merr.WrapErrImportFailed(fmt.Sprintf("invalid JSON format, the root key should be '%s', but get '%s'", RowRootNode, key))
+		}
+
+		// started by '['
+		t, err = j.dec.Token()
+		if err != nil {
+			return nil, merr.WrapErrImportFailed(fmt.Sprintf("failed to decode the JSON file, error: %v", err))
+		}
+
+		if t != json.Delim('[') {
+			return nil, merr.WrapErrImportFailed("invalid JSON format, rows list should begin with '['")
+		}
+	}
+	for j.dec.More() {
+		var value any
+		if err = j.dec.Decode(&value); err != nil {
+			return nil, merr.WrapErrImportFailed(fmt.Sprintf("failed to parse row, error: %v", err))
+		}
+		row, err := j.parser.Parse(value)
+		if err != nil {
+			return nil, err
+		}
+		err = insertData.Append(row)
+		if err != nil {
+			return nil, err
+		}
+		if insertData.GetMemorySize() >= j.bufferSize {
+			break
+		}
+	}
+
+	if !j.dec.More() {
+		t, err := j.dec.Token()
+		if err != nil {
+			return nil, merr.WrapErrImportFailed(fmt.Sprintf("failed to decode JSON, error: %v", err))
+		}
+		if t != json.Delim(']') {
+			return nil, merr.WrapErrImportFailed("invalid JSON format, rows list should end with ']'")
+		}
+	}
+
+	return insertData, nil
+}
+
+func (j *reader) Close() {}