I want to POST using an NSURLConnection, using a SOCKS proxy along the way.
From what I've read, NSURLConnection does support SOCKS and HTTP proxies. The question is, where do I configure it?
I couldn't find any suitable method on e.g. NSURLRequest for configuring which proxy server to use.
If this is a limitation, does anyone know of a good replacement that does support SOCKS?
Though I've never used it myself, from reading around the topic I think you need to use an NSOutputStream rather than an NSURLConnection, which is toll-free bridged with CFWriteStream. On that you can use CFWriteStreamSetProperty with the kCFStreamPropertySOCKSProxy key and a dictionary with corresponding entries for the various keys defined here.
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I'm new to network programming and have recently been playing around with using sockets in C++.
I have a pretty decent handle on it at this point, and I understand HTTP/TCP/IP packets pretty well.
However, upon doing some research online it seems like the bulk of network programmers suggest using external libraries such as libcurl (or curl++ for c++) for sending HTTP requests.
Considering that HTTP is a text-based protocol, why is this more beneficial/easier than simply sending HTTP requests as text messages using socket programming?
I found a few sites that show that you can do this without too much difficulty: HTTP Requests in C++ without external libraries?,
Simple C example of doing an HTTP POST and consuming the response
It seems like sending HTTP requests is simply a matter of getting the formatting correct and then sending it via a TCP socket. How is this made easier with external libraries?
Please bear with me as I'm new to network programming and eager to learn.
The links you've provided in your question are in a way a pretty good explanation on why you should not code HTTP yourself it: the first link only points to the socket API and does not say anything about HTTP while the second one provides some examples and code which are too much simplified for real world use and will not even work with with typical setup of multiple domains on the same host since the requests are missing the Host field. In other words: these are resources which might look useful to the inexperienced developer but they will actually lead you into trouble.
HTTP is not the simple as it might look. HTTP/0.9 was simple but is no longer supported by many clients. HTTP/1.0 is still kind of simple if restricted to the basic aspects. But there are already enough pitfalls, like using the wrong delimiter between lines and request header/body or not using a Host field when accessing multi-domain hosts.
And once you want to get efficient you want to have multiple requests per TCP connection and compression and then it gets more complex. With HTTP/1.1 it gets even more complex due to the use of chunked data encoding and with HTTP/2 it gets more efficient but way more complex with a binary protocol and interleaved requests and responses.
And this was only HTTP. With HTTPS you have the additional and not trivial TLS layer which has its own pitfalls.
Thus, if you just want to use HTTP and HTTPS it is much better to use established libraries. Of course if you want to learn the innards of HTTP it might be useful to read all the relevant standards, look at packet traces and try to implement your own.
According to the wiki, XMPP could use HTTP in two ways: one is polling and other one is binding. This binding model of notification is more efficient than polling, where many of the polls return no new data.
Can anybody explain to me,
how it work and
how to use the http-bind url (http://jabber.org:5280/) when we developing the client application using agsXmpp library.
XEP-0206 and XEP-0124 specify Bidirectional-streams Over Synchronous HTTP (BOSH), which is the protocol for the binding approach. I don't think agsXmpp supports BOSH, but their newer version (Matrix) does, as well as Jabber-Net.
I have an app that connects to an inhouse gameserver. I want to wrap the traffic in SSL to prevent hackers from sniffing the passwords and what not. Anyways, how do I go about doing that with an iphone app? I'm using CFNetwork to communicate to the server, and everything is in our own inhouse protocol instead of using http or something like that.
Thanks
You will need to set the appropriate CFStream properties prior to opening the streams. You do so by first preparing a dictionary using the appropriate kCFStreamSSL* keys and corresponding values and then calling CFWriteStreamSetProperty() to set that dictionary as the kCFStreamPropertySSLSettings property. The property should be shared between both streams in the connection pair.
If your server attempts to negotiate an SSL connection, I believe the streams will cooperate in the negotiation by default. You might have less work to do than you think.
I have a remote server with some files. I want to use AsyncSocket to download a file, chunk by chunk. I would like to send HTTP requests with ranges through the socket and get the appropriate chunks of data. I understand how to do this on localhost, but not from a remote server. I really don't know how to use the connectToHost and acceptOnInterface (previously acceptOnAddress) methods.
Please help
Thanks
AsyncSocket is a general purpose data connection. If you want it to talk HTTP, you'll need to code the HTTP portion yourself. You probably don't actually want this; NSURLConnection should do what you want, provided the server supports it.
What you're asking for is the Range: header in HTTP. See 14.35.2 in RFC2616. You just need to add this header to your NSURLRequest. Again, this presumes that the server you're talking to supports this (you need to check the Accept-Ranges: header in the response).
There's a short article with example code about this at Surgeworks.
You should also look at ASIHTTPRequest, which includes resumable downloads and download progress delgates, and can likely be adapted to doing partial downloads. It may already have the solution to the specific issue you're trying to solve.
I'm working on an iPhone application which will use long-polling to send event notifications from the server to the client over HTTP. After opening a connection on the server I'm sending small bits of JSON that represent events, as they occur. I am finding that -[NSURLConnectionDelegate connection:didReceiveData] is not being called until after I close the connection, regardless of the cache settings I use when creating the NSURLRequest. I've verified that the server end is working as expected - the first JSON event will be sent immediately, and subsequent events will be sent over the wire as they occur. Is there a way to use NSURLConnection to receive these events as they occur, or will I need to instead drop down to the CFSocket API?
I'm starting to work on integrating CocoaAsyncSocket, but would prefer to continue using NSURLConnection if possible as it fits much better with the rest of my REST/JSON-based web service structure.
NSURLConnection will buffer the data while it is downloading and give it all back to you in one chunk with the didReceiveData method. The NSURLConnection class can't tell the difference between network lag and an intentional split in the data.
You would either need to use a lower-level network API like CFSocket as you mention (you would have access to each byte as it comes in from the network interface, and could distinguish the two parts of your payload), or you could take a look at a library like CURL and see what types of output buffering/non-buffering there is there.
I ran into this today. I wrote my own class to handle this, which mimics the basic functionality of NSURLConnection.
http://github.com/nall/SZUtilities/blob/master/SZURLConnection.h
It sounds as if you need to flush the socket on the server-side, although it's really difficult to say for sure. If you can't easily change the server to do that, then it may help to sniff the network connection to see when stuff is actually getting sent from the server.
You can use a tool like Wireshark to sniff your network.
Another option for seeing what's getting sent/received to/from the phone is described in the following article:
http://blog.jerodsanto.net/2009/06/sniff-your-iphones-network-traffic/
Good luck!
We're currently doing some R&D to port our StreamLink comet libraries to the iPhone.
I have found that in the emulator you will start to get didReceiveData callbacks once 1KB of data is received. So you can send a junk 1KB block to start getting callbacks. It seems that on the device, however, this doesn't happen. In safari (on device) you need to send 2KB, but using NSURLConnection I too am getting no callbacks. Looks like I may have to take the same approach.
I might also play with multipart-replace and some other more novel headers and mime types to see if it helps stimulate NSURLConnection.
There is another HTTP API Implementation named ASIHttpRequest. It doesn't have the problem stated above and provides a complete toolkit for almost every HTTP feature, including File Uploads, Cookies, Authentication, ...
http://allseeing-i.com/ASIHTTPRequest/