NSURLProtocol簡(jiǎn)介
NSURLProtocol是URL Loading System的重要組成部分属拾。它是一個(gè)抽象類将谊。可以攔截網(wǎng)絡(luò)請(qǐng)求渐白∽鹋ǎ可以攔截的網(wǎng)絡(luò)請(qǐng)求包括NSURLSession，NSURLConnection以及UIWebvIew〈垦埽現(xiàn)也支持WKWebview框架栋齿，本文就是采用WKWebview。
方式
攔截做替換的方式有兩種
- 重定向到本地資源襟诸，利用canonicalRequestForRequest實(shí)現(xiàn)
- 根據(jù)url瓦堵，自定義response。
下面先說第一種實(shí)現(xiàn)方式：
1歌亲、無論哪種實(shí)現(xiàn)方式都必須注冊(cè)NSURLProtocol
我這里在AppDelegate的didFinishLaunchingWithOptions方法里面進(jìn)行注冊(cè)谷丸，代碼如下
- (BOOL)application:(UIApplication*)application didFinishLaunchingWithOptions:(NSDictionary*)launchOptions {
//注冊(cè)
[NSURLProtocol registerClass:[BaseOnRedirectRequestURLProtocol class]];
//實(shí)現(xiàn)攔截功能
Class cls = NSClassFromString(@"WKBrowsingContextController");
SEL sel = NSSelectorFromString(@"registerSchemeForCustomProtocol:");
if([(id)clsrespondsToSelector:sel]) {
#pragma clang diagnostic push
#pragma clang diagnostic ignored"-Warc-performSelector-leaks"
[(id)cls performSelector:sel withObject:@"myapp"];
#pragma clang diagnostic pop
}
return YES;
}
2、創(chuàng)建NSURLProtocol子類BaseOnRedirectRequestURLProtocol
- 在.m文件中 遵循協(xié)議<NSURLSessionDelegate>
- 創(chuàng)建 NSURLSessionDataTask 對(duì)象
? ? ? ?@property (nonnull,strong) NSURLSessionDataTask *task; - 下面是NSURLSession代理方法
- (void)URLSession:(NSURLSession *)session dataTask:(NSURLSessionDataTask *)dataTask didReceiveResponse:(NSURLResponse *)response completionHandler:(void (^)(NSURLSessionResponseDisposition))completionHandler {
[[self client] URLProtocol:self didReceiveResponse:response cacheStoragePolicy:NSURLCacheStorageAllowed];
completionHandler(NSURLSessionResponseAllow);
}
- (void)URLSession:(NSURLSession *)session dataTask:(NSURLSessionDataTask *)dataTask didReceiveData:(NSData *)data {
[[self client] URLProtocol:self didLoadData:data];
}
- (void)URLSession:(NSURLSession *)session task:(NSURLSessionTask *)task didCompleteWithError:(nullable NSError *)error {
[self.client URLProtocolDidFinishLoading:self];
}
3应结、準(zhǔn)備就緒后刨疼，下面開始實(shí)現(xiàn)攔截功能
- 注冊(cè)NSURLProtocol后，客戶端所有請(qǐng)求都將走+ (BOOL)canInitWithRequest:(NSURLRequest *)request鹅龄。
下面是代碼片段：
+ (BOOL)canInitWithRequest:(NSURLRequest *)request
{
NSLog(@"request.URL.absoluteString = %@",request.URL.absoluteString);
NSString *scheme = [[request URL] scheme];
if ( ([scheme caseInsensitiveCompare:@"http"] == NSOrderedSame ||
[scheme caseInsensitiveCompare:@"https"] == NSOrderedSame ))
{
//看看是否已經(jīng)處理過了揩慕，防止無限循環(huán)
if ([NSURLProtocol propertyForKey:BaseOnRedirectRequestURLProtocolKey inRequest:request])
return NO;
return YES;
}
return NO;
}
- request 重定向方法 下面代碼中的地址，改為你需要攔截的地址扮休，本地路徑也改為你需要替換的本地資源
+ (NSURLRequest *)canonicalRequestForRequest:(NSURLRequest *)request
{
NSMutableURLRequest *mutableReqeust = [request mutableCopy];
NSLog(@"url ---[%@]\n\n",request.URL.absoluteString);
//request截取重定向
if ([request.URL.absoluteString isEqualToString:@"http://xxx/xxx.js"])
{
NSString * filePath = [[NSBundle mainBundle] pathForResource:@"NewProject" ofType:@"js"];
NSURL * url = [NSURL fileURLWithPath:filePath];
mutableReqeust.URL = url;
}
return mutableReqeust;
}
- 在startLoading中開始加載
- (void)startLoading{
NSMutableURLRequest* request = self.request.mutableCopy;
[NSURLProtocol setProperty:@YES forKey:BaseOnRedirectRequestURLProtocolKey inRequest:request];
NSURLSession *session = [NSURLSession sessionWithConfiguration:[NSURLSessionConfiguration defaultSessionConfiguration] delegate:self delegateQueue:nil];
self.task = [session dataTaskWithRequest:self.request];
[self.task resume];
}
- stopLoading中記得銷毀
- (void)stopLoading
{
if (self.task != nil) {
[self.task cancel];
}
}
至此第一種攔截替換本地資源的方式已實(shí)現(xiàn)迎卤，控制器加載WKWebView在本文末尾寫
下面先說第二種實(shí)現(xiàn)方式：
1、首先同第一種方式玷坠，都需要注冊(cè)
- (BOOL)application:(UIApplication*)application didFinishLaunchingWithOptions:(NSDictionary*)launchOptions {
//注冊(cè)
[NSURLProtocol registerClass:[BaseOnResponseURLProtocol class]];
//實(shí)現(xiàn)攔截功能
Class cls = NSClassFromString(@"WKBrowsingContextController");
SEL sel = NSSelectorFromString(@"registerSchemeForCustomProtocol:");
if([(id)clsrespondsToSelector:sel]) {
#pragma clang diagnostic push
#pragma clang diagnostic ignored"-Warc-performSelector-leaks"
[(id)cls performSelector:sel withObject:@"myapp"];
#pragma clang diagnostic pop
}
return YES;
}
2蜗搔、創(chuàng)建NSURLProtocol子類BaseOnResponseURLProtocol
- 在.m文件中 遵循協(xié)議<NSURLConnectionDelegate>
- 創(chuàng)建 NSURLConnection 對(duì)象
? ? ? ?@property (nonatomic, strong) NSURLConnection *connection; - 下面是NSURLConnection代理方法
#pragma mark - NSURLConnectionDelegate
- (void) connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response {
[self.client URLProtocol:self didReceiveResponse:response cacheStoragePolicy:NSURLCacheStorageNotAllowed];
}
- (void) connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
[self.client URLProtocol:self didLoadData:data];
}
- (void) connectionDidFinishLoading:(NSURLConnection *)connection {
[self.client URLProtocolDidFinishLoading:self];
}
- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error {
[self.client URLProtocol:self didFailWithError:error];
}
3、準(zhǔn)備就緒后八堡，下面開始實(shí)現(xiàn)攔截功能
- 注冊(cè)NSURLProtocol后樟凄，客戶端所有請(qǐng)求都將走+ (BOOL)canInitWithRequest:(NSURLRequest *)request。
+ (BOOL)canInitWithRequest:(NSURLRequest *)request
{
NSLog(@"request.URL.absoluteString = %@",request.URL.absoluteString);
if ( ([request.URL.absoluteString hasPrefix:@"http://game.scool.online/cutcake1/"]))
{
//看看是否已經(jīng)處理過了兄渺，防止無限循環(huán)
if ([NSURLProtocol propertyForKey:BaseOnResponseURLProtocolKey inRequest:request]) {
return NO;
}
return YES;
}
return NO;
}
- 在startLoading中加載缝龄，實(shí)現(xiàn)思路：將需要替換的地址重新拼接response返回，再響應(yīng)本地資源挂谍，代碼如下：
- (void)startLoading {
//1.獲取資源文件路徑 ajkyq/index.html
NSURL *url = [self request].URL;
//2.讀取資源文件內(nèi)容
NSString *path = [[NSBundle mainBundle] pathForResource:@"NewProject" ofType:@"js"];
NSFileHandle *file = [NSFileHandle fileHandleForReadingAtPath:path];
NSData *data = [file readDataToEndOfFile];
[file closeFile];
//3.拼接響應(yīng)Response
NSInteger dataLength = data.length;
NSString *mimeType = [self getMIMETypeWithCAPIAtFilePath:path];
NSString *httpVersion = @"HTTP/1.1";
NSHTTPURLResponse *response = nil;
if (dataLength > 0) {
response = [self jointResponseWithData:data dataLength:dataLength mimeType: mimeType requestUrl:url statusCode:200 httpVersion:httpVersion];
} else {
response = [self jointResponseWithData:[@"404" dataUsingEncoding:NSUTF8StringEncoding] dataLength:3 mimeType:mimeType requestUrl:url statusCode:404 httpVersion:httpVersion];
}
//4.響應(yīng)
[[self client] URLProtocol:self didReceiveResponse:response cacheStoragePolicy:NSURLCacheStorageNotAllowed];
[[self client] URLProtocol:self didLoadData:data];
[[self client] URLProtocolDidFinishLoading:self];
}
- jointResponseWithData方法實(shí)現(xiàn)如下：
#pragma mark - 拼接響應(yīng)Response
-(NSHTTPURLResponse *)jointResponseWithData:(NSData *)data dataLength:(NSInteger)dataLength mimeType:(NSString *)mimeType requestUrl:(NSURL *)requestUrl statusCode:(NSInteger)statusCode httpVersion:(NSString *)httpVersion
{
NSDictionary *dict = @{@"Content-type":mimeType,
@"Content-length":[NSString stringWithFormat:@"%ld",dataLength]};
NSHTTPURLResponse *response = [[NSHTTPURLResponse alloc] initWithURL:requestUrl statusCode:statusCode HTTPVersion:httpVersion headerFields:dict];
return response;
}
- MIMEType類型獲取如下
#pragma mark - 獲取mimeType
-(NSString *)getMIMETypeWithCAPIAtFilePath:(NSString *)path
{
if (![[[NSFileManager alloc] init] fileExistsAtPath:path]) {
return @"text/html";
}
CFStringRef UTI = UTTypeCreatePreferredIdentifierForTag(kUTTagClassFilenameExtension, (__bridge CFStringRef)[path pathExtension], NULL);
CFStringRef MIMEType = UTTypeCopyPreferredTagWithClass (UTI, kUTTagClassMIMEType);
CFRelease(UTI);
if (!MIMEType) {
return @"application/octet-stream";
}
return (__bridge NSString *)(MIMEType);
}
至此第二種實(shí)現(xiàn)方式也已完成叔壤，下面貼上控制器中的代碼
1、引用#import <WebKit/WebKit.h> 和 #import "NSURLProtocol+WKWebVIew.h" 并遵循<WKNavigationDelegate,WKUIDelegate>
NSURLProtocol+WKWebVIew 是對(duì)NSURLProtocol的一個(gè)擴(kuò)展口叙，主要是注冊(cè)http和https協(xié)議炼绘，本文不做介紹，demo里會(huì)有的妄田。
2俺亮、聲明WKWebView對(duì)象
? ? ? ?@property (nonatomic) WKWebView* webView;
3仗哨、viewDidLoad中代碼
- (void)viewDidLoad {
[super viewDidLoad];
[NSURLProtocol wk_registerScheme:@"http"];
[NSURLProtocol wk_registerScheme:@"https"];
[self.view addSubview:self.webView];
}
4、WKWebView懶加載
- (WKWebView *)webView {
if (!_webView) {
WKWebViewConfiguration *configuration = [[WKWebViewConfiguration alloc] init];
configuration.userContentController = [WKUserContentController new];
WKPreferences *preferences = [WKPreferences new];
preferences.javaScriptCanOpenWindowsAutomatically = YES;
preferences.minimumFontSize = 30.0;
configuration.preferences = preferences;
_webView = [[WKWebView alloc] initWithFrame:self.view.frame configuration:configuration];
_webView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
if ([_webView respondsToSelector:@selector(setNavigationDelegate:)]) {
[_webView setNavigationDelegate:self];
}
// if ([_webView respondsToSelector:@selector(setDelegate:)]) {
[_webView setUIDelegate:self];
// }
NSURL *url = [NSURL URLWithString:@"http://game.scool.online/cutcake1/"];
NSURLRequest *request = [NSURLRequest requestWithURL:url];
[_webView loadRequest:request];
}
return _webView;
}
5铅辞、別忘記回調(diào)哦
- (void)webView:(WKWebView *)webView runJavaScriptAlertPanelWithMessage:(NSString *)message initiatedByFrame:(WKFrameInfo *)frame completionHandler:(void (^)(void))completionHandler {
completionHandler();
}
