# Configuration Policy Component

## Introduction

The configuration policy component, namely, customization_config_policy, provides APIs for each service module to obtain the configuration directories at different levels or the configuration file paths.

## System Architecture

**Figure 1** Architecture of the configuration policy component

![](figures/config_policy_en.png)

The architecture is described as follows:

- **interfaces** provides the path of the file with the highest priority and all-level paths of the specified file.
- **frameworks** initializes the configuration directory and queries the file path.

## Directory Structure

The code directory structure of the configuration policy component is as follows:

```
/base/customization/
├── config_policy           # Code repository for the configuration policy component
│   ├── frameworks          # Core code of the configuration policy component
│   │   ├── config_policy   # Configuration policy module
│   │   │   └── src         # Implementation code
│   ├── interfaces          # APIs of the configuration policy component
│   │   ├── inner_api       # APIs for internal subsystems
│   │   └── kits            # JavaScript APIs of the configurationpolicy component
│   └── test                # Test code
```

## Usage

Call the APIs of the configuration policy component to obtain the configuration directories at different levels or the configuration file paths.

```
#include "config_policy_utils.h"

CfgDir *cfgDir = GetCfgDirList(); // Obtain the configuration directory list.
FreeCfgDirList(cfgDir); // Release the memory after the list is obtained.

const char *cfgPath = "etc/xml/cfg.xml"; // Set the relative path and name of the configuration file.
CfgFiles *cfgFiles = GetCfgFiles(cfgPath); // Obtain the configuration file paths of all configuration levels.
FreeCfgFiles(cfgFiles); // Release the memory after the information is obtained.

const char *userPath = "etc/xml/user.xml"; // Set the relative path and name of the configuration file.
char buf[MAX_PATH_LEN] = {0};
char *filePath = GetOneCfgFile(userPath, buf, MAX_PATH_LEN); // Obtain the path of the configuration file with the highest priority.
```

## Constraints

**Programming language**: C/C++

## Repositories Involved

**customization\_config\_policy**

# 配置策略组件介绍

## 简介

配置策略组件为各业务模块提供获取各配置层级的配置目录或配置文件路径的接口。

## 系统架构

**图 1**  配置策略组件架构图

![](figures/config_policy.png)

配置策略组件架构图说明：

- interfaces对外提供指定文件的最高优先级文件路径以及指定文件所有层级路径。
- frameworks实现配置层级目录的初始化与文件路径查询。

## 目录

配置策略组件源代码目录结构如下所示：

```
/base/customization/
├── config_policy           # 配置策略代码仓
│   ├── frameworks          # 配置策略核心代码
│   │   ├── config_policy   # 配置策略模块
│   │   │   └── src         # 实现代码
│   ├── interfaces          # 配置策略接口
│   │   ├── inner_api       # 子系统间接口
│   │   └── kits            # 配置策略JavaScript接口
│   └── test                # 测试代码
```

## 说明

调用该组件中的接口获取各配置层级的配置目录或配置文件路径。

```
#include "config_policy_utils.h"

CfgDir *cfgDir = GetCfgDirList(); // 获取配置层级目录列表
FreeCfgDirList(cfgDir); // 获取完成后需要释放内存

const char *cfgPath = "etc/xml/cfg.xml"; // 设置配置文件相对路径及文件名
CfgFiles *cfgFiles = GetCfgFiles(cfgPath); // 获取所有配置层级的配置文件路径
FreeCfgFiles(cfgFiles); // 获取完成后需要释放内存

const char *userPath = "etc/xml/user.xml"; // 设置配置文件相对路径及文件名
char buf[MAX_PATH_LEN] = {0};
char *filePath = GetOneCfgFile(userPath, buf, MAX_PATH_LEN); // 获取最高优先级的配置文件路径
```

## 约束

**语言限制**：C/C++语言

## 相关仓

**customization\_config\_policy**