# ip2region nodejs 查询客户端实现

## 使用方式

### 完全基于文件的查询

```javascript
// 导入包
const Searcher = require('.')
// 指定ip2region数据文件路径
const dbPath = 'ip2region.xdb file path'

try {
  // 创建searcher对象
  const searcher = Searcher.newWithFileOnly(dbPath)
  // 查询
  const data = await searcher.search('218.4.167.70')
  // data: {region: '中国|0|江苏省|苏州市|电信', ioCount: 3, took: 1.342389}
} catch(e) {
  console.log(e)
}

```

### 缓存 `VectorIndex` 索引

```javascript
// 导入包
const Searcher = require('.')
// 指定ip2region数据文件路径
const dbPath = 'ip2region.xdb file path'

try {
  // 同步读取vectorIndex
  const vectorIndex = Searcher.loadVectorIndexFromFile(dbPath)
  // 创建searcher对象
  const searcher = Searcher.newWithVectorIndex(dbPath, vectorIndex)
  // 查询 await 或 promise均可
  const data = await searcher.search('218.4.167.70')
  // data: {region: '中国|0|江苏省|苏州市|电信', ioCount: 2, took: 0.402874}
} catch(e) {
  console.log(e)
}
```

### 缓存整个 `xdb` 数据

```javascript
// 导入包
const Searcher = require('.')
// 指定ip2region数据文件路径
const dbPath = 'ip2region.xdb file path'

try {
  // 同步读取buffer
  const buffer = Searcher.loadContentFromFile(dbPath)
  // 创建searcher对象
  const searcher = Searcher.newWithVectorIndex(buffer)
  // 查询 await 或 promise均可
  const data = await searcher.search('218.4.167.70')
  // data: {region:'中国|0|江苏省|苏州市|电信', ioCount: 0, took: 0.063833}
} catch(e) {
  console.log(e)
}
```

## 查询测试

可以通过 `java -jar ip2region-{version}.jar search` 命令来测试查询：

```shell
➜  nodejs git:(v2.0-for-nodejs) ✗ node ./tests/test.app.js --help
usage: Usage node test.app.js <agrs>

ip2region test app

optional arguments:
  -h, --help            show this help message and exit
  -d DB, --db DB        ip2region binary xdb file path, default: ../../data/ip2region.xdb
  -c CACHE_POLICY, --cache-policy CACHE_POLICY
                        cache policy: file/vectorIndex/content, default: content
```

例如：使用默认的 data/ip2region.xdb 文件进行查询测试：

```shell
➜  nodejs git:(v2.0-for-nodejs) ✗ node ./tests/test.app.js
parameters:
    dbPath: ../../data/ip2region.xdb
    cache-policy: content

type 'quit' to exit
ip2region>> 1.2.3.4
{ region: '美国|0|华盛顿|0|谷歌', ioCount: 0, took: 0.606261 }
ip2region>>
```

输入 ip 即可进行查询测试，也可以分别设置 `cache-policy` 为 file/vectorIndex/content 来测试三种不同缓存实现的查询效果。

## bench 测试

## 单元测试结果

```shell
ip2region
  ✔ #newWithFileOnly
  ✔ #newWithVectorIndex
  ✔ #newWithBuffer

3 passing (10ms)

----------|---------|----------|---------|---------|----------------------------------
File      | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s
----------|---------|----------|---------|---------|----------------------------------
All files |   91.17 |    60.71 |     100 |   91.17 |
 index.js |   91.17 |    60.71 |     100 |   91.17 | 56,70,80,137,143,173,179,193,201
----------|---------|----------|---------|---------|----------------------------------
```