使用带有 UIWebView 和 POST 请求的自定义 NSURLProtocol [英] Using a custom NSURLProtocol with UIWebView and POST requests

问题描述

在我的 iOS 应用程序中，我使用 UIWebView 和自定义协议(使用我自己的 NSURLProtocol 实现).我一直非常小心地确保每当我加载一个 url 时，我都会将这样的内容加载到我的 UIWebView 中:

In my iOS app, I'm using a UIWebView and a custom protocol (with my own NSURLProtocol implementation). I've been fairly careful about making sure that whenever I load a url, I load something like this into my UIWebView:

myprotocol://myserver/mypath

myprotocol://myserver/mypath

在我的 NSURLProtocol 实现中，我获取 NSURLRequest 的可变副本，将 URL 转换为 http: 并将其发送到我的服务器.

and in my NSURLProtocol implementation, I take a mutable copy of the NSURLRequest, convert the URL to http: and send that to my server.

一切都适用于 HTTP GET 请求.我遇到的问题是 POST 请求.如果请求使用我的自定义协议，UIWebView 似乎没有正确编码 HTTPBody 中的表单数据.

Everything works for HTTP GET requests. The problem I encounter is with POST requests. It seems like the UIWebView doesn't properly encode the form data in the HTTPBody if the request uses my custom protocol.

一种解决方法，因为我对服务器请求使用 HTTPS，所以我注册协议处理程序以拦截 http: 而不是 myprotocol: 并且我可以将所有调用转换为 https: This other question, 这里，向我指出了那个解决方案:

One work-around, since I'm using HTTPS for my server requests, is that I register my protocol handler to intercept http: instead of myprotocol: and I can convert all calls to https: This other question, here, pointed me toward that solution:

但我想知道是否有任何替代和/或更好的方法来完成我想要的.

But I'm wondering if there's any alternative and/or better way of accomplishing what I want.

推荐答案

不尝试使用 POST 请求，一种解决方法是继续对 myprotocol:// URL 使用 GET 请求，但要转换将它们在您的 NSURLProtocol 实现中发送到 http:// 和 POST 请求到您的服务器，使用请求查询字符串作为 POST 的正文.

Instead of trying to use POST requests, one work around is to continue using GET requests for myprotocol:// URLs, but transform them in your NSURLProtocol implementation to an http:// and POST request to your server using the request query string as the body of the POST.

使用 GET 请求发送大量数据的担忧是，在请求链的某个地方，请求行可能会被截断.但是，对于本地实现的协议，这似乎不是问题.

The worry with using GET requests to send large amounts of data is that somewhere along the request chain, the request line might get truncated. This appears to not be a problem, however, with locally-implemented protocols.

我编写了一个简短的 Cordova 测试应用程序来进行实验，我发现我能够毫无问题地将超过 1 MiB 的数据发送到 HTTP 请求回显服务 http://http-echo.jgate.de/

I wrote a short Cordova test app to experiment and I found that I was able to send through a little over 1 MiB of data without trouble to the HTTP request echoing service http://http-echo.jgate.de/

这是我的 startLoading 实现:

- (void)startLoading {
    NSURL *url = [[self request] URL];
    NSString *query = [url query];
    // Create a copy of `url` without the query string.
    url = [[[NSURL alloc] initWithScheme:@"http" host:@"http-echo.jgate.de" path:[url path]] autorelease];
    NSMutableURLRequest *newRequest = [NSMutableURLRequest requestWithURL:url];
    [newRequest setHTTPMethod:@"POST"];
    [newRequest setAllHTTPHeaderFields:[[self request] allHTTPHeaderFields]];
    [newRequest addValue:@"close" forHTTPHeaderField:@"Connection"];
    [newRequest addValue:@"application/x-www-form-urlencoded;charset=UTF-8" forHTTPHeaderField:@"Content-Type"];
    [newRequest setHTTPBody:[query dataUsingEncoding:NSUTF8StringEncoding]];
    urlConnection = [[NSURLConnection alloc] initWithRequest:newRequest delegate:self];
    if (urlConnection) {
        receivedData = [[NSMutableData data] retain];
    }
}

然后我实现了 NSURLConnection 协议方法以转发到适当的 NSURLProtocolClient 方法，但在 Transfer-Encoding:chunked 的情况下构建响应数据(就像来自 http://http-echo.jgate.de/ 的响应的情况).

I then implemented the NSURLConnection protocol methods to forward to the appropriate NSURLProtocolClient method, but building up the response data in the case of Transfer-Encoding:chunked (as is the case for responses from http://http-echo.jgate.de/).

这篇关于使用带有 UIWebView 和 POST 请求的自定义 NSURLProtocol的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！