# iOS SDK

## 初始化

```objc
HttpdnsEdgeService *service = [[HttpdnsEdgeService alloc]
    initWithAppId:@"app1f1ndpo9"
primaryServiceHost:@"httpdns-a.example.com"
 backupServiceHost:@"httpdns-b.example.com"
        servicePort:443
         signSecret:@"your-sign-secret"];
```

## 解析

```objc
[service resolveHost:@"api.business.com" queryType:@"A" completion:^(HttpdnsEdgeResolveResult * _Nullable result, NSError * _Nullable error) {
    // result.ipv4s / result.ipv6s
}];
```

## 官方业务适配器

```objc
NSURL *url = [NSURL URLWithString:@"https://api.business.com/v1/ping"];
[service requestURL:url method:@"GET" headers:nil body:nil completion:^(NSData * _Nullable data, NSHTTPURLResponse * _Nullable response, NSError * _Nullable error) {
    // handle
}];
```

固定策略：IP 直连 + 空 SNI + Host=真实域名，不回退到带 SNI。