[to-reply] feature: support saga multi type config

pkg/saga/statemachine/statelang/parser/statemachine_config_parser.go

@@ -0,0 +1,147 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) 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 parser
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"gopkg.in/yaml.v3"
+	"io"
+	"os"
+	"path/filepath"
+)
+
+// ConfigParser is a general configuration parser interface, used to agree on the implementation of different types of parsers
+type ConfigParser interface {
+	Parse(configContent []byte) (*StateMachineObject, error)
+}
+
+type StateMachineConfigParser struct{}
+
+func NewStateMachineConfigParser() *StateMachineConfigParser {
+	return &StateMachineConfigParser{}
+}
+
+func (p *StateMachineConfigParser) checkConfigFile(configFilePath string) error {
+	_, err := os.Stat(configFilePath)
+	if os.IsNotExist(err) {
+		return fmt.Errorf("config file %s does not exist: %w", configFilePath, err)
+	}
+	if err != nil {
+		return fmt.Errorf("failed to access config file %s: %w", configFilePath, err)
+	}
+	return nil
+}
+
+func (p *StateMachineConfigParser) readFile(configFilePath string) ([]byte, error) {
+	file, _ := os.Open(configFilePath)
+	defer func(file *os.File) {
+		_ = file.Close()
+	}(file)
+
+	var buf bytes.Buffer
+	_, err := io.Copy(&buf, file)
+	if err != nil {
+		return nil, fmt.Errorf("failed to read config file %s: %w", configFilePath, err)
+	}
+
+	return buf.Bytes(), nil
+}
+
+func (p *StateMachineConfigParser) getParser(configFilePath string) (ConfigParser, error) {
+	fileExt := filepath.Ext(configFilePath)
+	// check the file extension, compatible with some illegal but possible situations
+	switch fileExt {
+	case ".json", ".JSON":
+		return NewJSONConfigParser(), nil
+	case ".yaml", ".yml", ".YAML", ".YML":
+		return NewYAMLConfigParser(), nil
+	default:
+		return nil, fmt.Errorf("unsupported config file format: %s", fileExt)
+	}
+}
+
+func (p *StateMachineConfigParser) Parse(configFilePath string) (*StateMachineObject, error) {
+	if err := p.checkConfigFile(configFilePath); err != nil {
+		return nil, err
+	}
+
+	configContent, err := p.readFile(configFilePath)
+	if err != nil {
+		return nil, err
+	}
+
+	parser, err := p.getParser(configFilePath)
+	if err != nil {
+		return nil, err
+	}
+
+	return parser.Parse(configContent)
+}
+
+type JSONConfigParser struct{}
+
+func NewJSONConfigParser() *JSONConfigParser {
+	return &JSONConfigParser{}
+}
+
+func (p *JSONConfigParser) Parse(configContent []byte) (*StateMachineObject, error) {
+	if configContent == nil || len(configContent) == 0 {
+		return nil, fmt.Errorf("empty JSON config content")
+	}
+
+	var stateMachineObject StateMachineObject
+	if err := json.Unmarshal(configContent, &stateMachineObject); err != nil {
+		return nil, fmt.Errorf("failed to parse JSON config content: %w", err)
+	}
+
+	return &stateMachineObject, nil
+}
+
+type YAMLConfigParser struct{}
+
+func NewYAMLConfigParser() *YAMLConfigParser {
+	return &YAMLConfigParser{}
+}
+
+func (p *YAMLConfigParser) Parse(configContent []byte) (*StateMachineObject, error) {
+	if configContent == nil || len(configContent) == 0 {
+		return nil, fmt.Errorf("empty YAML config content")
+	}
+
+	var stateMachineObject StateMachineObject
+	if err := yaml.Unmarshal(configContent, &stateMachineObject); err != nil {
+		return nil, fmt.Errorf("failed to parse YAML config content: %w", err)
+	}
+
+	return &stateMachineObject, nil
+}
+
+type StateMachineObject struct {
+	Name                        string                 `json:"Name" yaml:"Name"`
+	Comment                     string                 `json:"Comment" yaml:"Comment"`
+	Version                     string                 `json:"Version" yaml:"Version"`
+	StartState                  string                 `json:"StartState" yaml:"StartState"`
+	RecoverStrategy             string                 `json:"RecoverStrategy" yaml:"RecoverStrategy"`
+	Persist                     bool                   `json:"IsPersist" yaml:"IsPersist"`
+	RetryPersistModeUpdate      bool                   `json:"IsRetryPersistModeUpdate" yaml:"IsRetryPersistModeUpdate"`
+	CompensatePersistModeUpdate bool                   `json:"IsCompensatePersistModeUpdate" yaml:"IsCompensatePersistModeUpdate"`
+	Type                        string                 `json:"Type" yaml:"Type"`
+	States                      map[string]interface{} `json:"States" yaml:"States"`
+}