WEEX + HTTPDNS iOS解决方案
由于WebView并未暴露处设置DNS的接口，因而在WebView场景下使用HttpDns存在很多无法限制，但如果接入WEEX,则可以较好地植入HTTPDNS，本文主要介绍在WEEX场景下接入HTTPDNS的方案细节。
在WEEX运行时环境下，所有的逻辑最终都会转换到Native Runtime中执行，网络请求也不例外。同时WEEX也提供了自定义相应实现的接口，通过重写网络请求适配器，我们可以较为简单地接入HTTPDNS。在WEEX运行环境中，主要有两种网络请求：
下面以 weex iOS 0.7.0 版本为例：
Stream网络请求 + HTTPDNS
Stream网络请求在 iOS 端最终会通过WXNetworkDefaultImpl完成，同时WEEX也提供了相应的接口自定义网络请求适配器。具体的逻辑如下：
第一步：创建自定义网络请求适配器，实现 WXNetworkHttpDnsImpl 接口
#import #import "WXNetworkDefaultImpl.h"@interface WXNetworkHttpDnsImpl : NSObject @end
第二步：在WEEX初始化时注册自定义网络适配器，替换默认适配器：
[WXSDKEngine registerHandler:[WXNetworkHttpDnsImpl new] withProtocol:@protocol(WXNetworkProtocol)];
之后的网络请求都会通过WXNetworkHttpDnsImpl实现，所以只需要在WXNetworkHttpDnsImpl中植入 HTTPDNS 逻辑即可，具体逻辑可以参考如下代码：
#import "WXNetworkDefaultImpl.h"@interface WXNetworkCallbackInfo : NSObject@property (nonatomic, copy) void(^sendDataCallback)(int64_t, int64_t);@property (nonatomic, copy) void(^responseCallback)(NSURLResponse *);@property (nonatomic, copy) void(^receiveDataCallback)(NSData *);@property (nonatomic, strong) NSMutableData *data;@property (nonatomic, copy) void(^compeletionCallback)(NSData *, NSError *);@end@implementation WXNetworkCallbackInfo@end@implementation WXNetworkDefaultImpl{ NSMutableDictionary *_callbacks; NSURLSession *_session;}- (id)sendRequest:(NSURLRequest *)request withSendingData:(void (^)(int64_t, int64_t))sendDataCallback withResponse:(void (^)(NSURLResponse *))responseCallback withReceiveData:(void (^)(NSData *))receiveDataCallback withCompeletion:(void (^)(NSData *, NSError *))compeletionCallback{ WXNetworkCallbackInfo *info = [WXNetworkCallbackInfo new]; info.sendDataCallback = sendDataCallback; info.responseCallback = responseCallback; info.receiveDataCallback = receiveDataCallback; info.compeletionCallback = compeletionCallback; if (!_session) { _session = [NSURLSession sessionWithConfiguration:[NSURLSessionConfiguration defaultSessionConfiguration] delegate:self delegateQueue:[NSOperationQueue mainQueue]]; } NSURLSessionDataTask *task = [_session dataTaskWithRequest:request]; if (!_callbacks) { _callbacks = [NSMutableDictionary dictionary]; } [_callbacks setObject:info forKey:task]; [task resume]; return task;}- (void)URLSession:(NSURLSession *)session task:(NSURLSessionTask *)task didSendBodyData:(int64_t)bytesSent totalBytesSent:(int64_t)totalBytesSent totalBytesExpectedToSend:(int64_t)totalBytesExpectedToSend{ WXNetworkCallbackInfo *info = [_callbacks objectForKey:task]; if (info.sendDataCallback) { info.sendDataCallback(totalBytesSent, totalBytesExpectedToSend); }}- (void)URLSession:(NSURLSession *)session dataTask:(NSURLSessionDataTask *)task didReceiveResponse:(NSURLResponse *)response completionHandler:(void (^)(NSURLSessionResponseDisposition))completionHandler{ WXNetworkCallbackInfo *info = [_callbacks objectForKey:task]; if (info.responseCallback) { info.responseCallback(response); } completionHandler(NSURLSessionResponseAllow);}- (void)URLSession:(NSURLSession *)session dataTask:(NSURLSessionDataTask *)task didReceiveData:(NSData *)data{ WXNetworkCallbackInfo *info = [_callbacks objectForKey:task]; if (info.receiveDataCallback) { info.receiveDataCallback(data); } NSMutableData *mutableData = info.data; if (!mutableData) { mutableData = [NSMutableData new]; info.data = mutableData; } [mutableData appendData:data];}- (void)URLSession:(NSURLSession *)session task:(NSURLSessionTask *)task didCompleteWithError:(NSError *)error{ WXNetworkCallbackInfo *info = [_callbacks objectForKey:task]; if (info.compeletionCallback) { info.compeletionCallback(info.data, error); } [_callbacks removeObjectForKey:task];}@end 1.2 <image>网络请求 + HTTPDNS
WEEX并没有提供默认的图片适配器实现，所以用户必须自行实现才能完成图片请求逻辑，具体步骤分为以下几步：
第一步：自定义图片请求适配器，实现IWXImgLoaderAdapter接口
#import "WXImgLoaderProtocol.h"@interface WXImgLoaderDefaultImpl : NSObject @end
第二步：在WEEX初始化时注册该图片适配器：
[WXSDKEngine registerHandler:[WXImgLoaderDefaultImpl new] withProtocol:@protocol(WXImgLoaderProtocol)];
所以同WXNetworkHttpDnsImpl一样，我们只需在WXNetworkHttpDnsImpl植入HTTPDNS逻辑即可。