I have an older statusing application that uses DataGramSockets to send/rec status messages from a number of programs. I want to convert this reporting app to use web services so it can also be queried from web pages.
Is it possible to have both the socket listening on its usual port while another service, second thread, listen to an http port for web connections?
You can easily use Java socket.io Library (for example) to use websocket/websocket secure over http/https.
So I will be using web sockets at this point. I see there really is no perfect answer to this question and its a little open ended. Ill get it closed.
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I'm developing an iOS app that requires realtime dual-way server/client messaging.
I'm trying to use WebSocket++ to develop a WebSocket server app on an AWS EC2. Have to use C++ because that's the only language I know on the server side.
The problem is I'm a fresh guy on server side development. I have 2 very basic questions:
1, Do I need have to setup an HTTP server like apache/nginx in order to get websocket running?
That is, can websocket app live independently alone?
2, I have now setup an nginx server in case it is a must have, is there any resource that I can refer to to make nginx & websocket work together well?
No, you don't need a Web server, a (reverse) Web proxy or anything to have your C++ WebSocket server talk to WebSocket clients.
Nginx (as HAproxy) supports reverse proxying WebSocket. This can make sense in certain situations, like you want to terminate TLS at the proxy and forward plain WebSocket to your backend server, or you want to load-balance incoming WebSocket connections to multiple backend nodes. However, as said, this isn't required.
No you don't, websocket and socket for an HTTP server are two diffent things.
HTTP server is for the HTTP protocol while there is not protocol defined for websocket, you have to define it yourself typically by the mean of sending/receiving Json message (a stream of character which each side (the server and the client) knows how to read/write).
The goal of websocket is to offer to javascript through HTML5 an easy, light and quick way to communicate through a socket, without websocket you have to do that with web services and in that case you need a http server.
With websocket you can create an html file leveraging html tag and javascript, javascript use client side of websocket to communicate with a C++/websocket server program, and you do not need even a web server, in this scenario you have a "desktop web app" ! (here web term is only because you use html tags)
Same question, same answer, no again ;-)
Good luck, and welcome in the wonderful world of asio !
Im new in C++.
I need to listen HTTP requests.
Please advice me some good tutorials or examples
Thanks
update:
Platform: Windows
Language: C++
I will explain more clearly what i need
when user clicks row on this page: http://ucp-anticheat.org/monitor.html applications is automatically starts on client machine.
I want to make same thing.
I think on client side is service which listens http requests and if url starts with steam:// service automatically runs application...
Do i need to listen http requests?
What is best solution for my problem?
You can listen to http requests through a web server like mongoose , which can be easily used in C++ http://code.google.com/p/mongoose/ , and here is a good example of using mongoose web server http://code.google.com/p/mongoose/source/browse/examples/hello.c
I m not sure what you mean 'client side', if you are meaning Browser as your client, you can't control nothing outside your browser. If you want to control a machine, you need your client machine to run your exe, that has the code to act based on your server instructions.
You should create a simple server program, create a SOCKET listening on default http, https etc, ports. Usually we do it inside a loop (at each one you make a read).
Now... would be easer if you specified if you are on Unix like OS or Windows, but from now on you can google it. Like sys/socket.h or try "man 7 socket" on almost all linux (at least the ones I know).
If you want to sniff something you can google some specific apps around web.
If i get your question right, you want to be able to launch an application when someone clicks a link with a custom protocol, like steam:// or telnet://. You are looking for an Protocol Handler.
A simple way to register such an application is using the ftype program, as described here.
I am writing an app on Thrift and webservice deployed on Websphere. Thrift client will be calling thrift server which inturn make a webservice call to webservice deployed on websphere.
Where will I host Thrift server implementation since it will be standalone app? Can it be started before/on startup of Websphere app server?
Shall I run Thrift as a standalone and then how will Thrift server get the common VOs being shared between Thrift server (which is client to webservice) and server(webservice hosted on Websphere)?
What should be right approach in this case since Thrift will be opening a socket which is making a websphere call even though both servers are collocated?
Is it safe to use sockets as a medium of rmi/rpc instead of http? What will be security loopholes since port will be opened for communication?
Thanks.
Quick reply will be highly appreciated.
Thrift service might be implemented either as a standalone application or as an webapp running on the same app server. In latter case thrift service doesn't have to serve any http requests, it should just start thrift server on app startup/shutdown. The advantage is that you can utilize all appserver infrastructure: lifecycle, monitoring, JMX, etc.
To share VOs between two JVMs, it's usually enough to make them 'implements Serializable' and add classes to both classpaths. Sharing within single JVM is trivial. So, there should be no problems here.
Yes, socket communication is just fine, even if servers are collocated.
Yes, it is safe enough, if configured properly. Restricting access to corresponding ports with firewall is probably the easiest.
I want to connect from webserver via dedicated proxy to the intranet. I am not sure if it matters I want to send and receive XML. It would be great if I could use HTTP.
I know of one open port 78xx which I successfully used with a TCP socket as described in this excellent tutorial
Is it possible? Or does the answer depend on the actual proxy configuration - if it scans for the protocol, and dislikes it it's gonna be blocked!?
And what library would you recommend? I just found pion - Can i link it statically? It's almost not possible to install sth on the web server for me.
EDIT My question is probably two-fold:
First, I have to add, there is an existing communication client+server, but the server is a mixup of the concrete socket and networking implementation and the API to the database, consisting of about 10 commands I find hard to extend. So I ask for a generic lib so I can rewrite that API from scratch.
Second, I need session handling, the webapplication passes the user login data to that client and there is a session-id returned which is used for all further communication - until it expires. That was the reason I asked for HTTP, but meanwhile i realized http itself is stateless.
The answer is.... in progress.- I need to practice more with c++ tcp libs etc.
My post was unfortunately hard too understand, Had some confusion about that all.
I am pretty new to security aspect of application. I have a C++ window service (server) that listens to a particular port for http requests. The http requests can be made via ajax or C# client. Due to some scope change now we have to secure this communication between the clients and custom server written in C++.
Therefore i am looking for options to secure this communication. Can someone help me out with the possible approaches i can take to achieve this.
Thanks
Dpak
Given that you have an existing HTTP server (non-IIS) and you want to implement HTTPS (which is easy to screw up and hard to get right), you have a couple of options:
Rewrite your server as a COM object, and then put together an IIS webservice that calls your COM object to implement the webservice. With this done, you can then configure IIS to provide your webservice via HTTP and HTTPS.
Install a proxy server (Internet Security and Acceleration Server or Apache with mod_proxy) on the same host as your existing server and setup the proxy server to listen via HTTPS and then reverse proxy the requests to your service.
The second option requires little to no changes to your application; the first option is the better long-term architectural move.
Use HTTPS.
A good toolkit for securing your communication channel is OpenSSL.
That said, even with a toolkit, there are plenty of ways to make mistakes when implementing your security layer that can leave your data open to attack. You should consider using an existing https server and having it forward the requests to your server on the loopback channel.
It's reasonably easy to do this using either OpenSSL or Microsoft's SChannel SSPI interface.
How complex it is for you depends on how you've structured your server. If it's a traditional style BSD sockets 'select' type server then it should be fairly straight forward to take the examples from either OpenSSL or SChannel and get something working pretty quickly.
If you're using a more complex server design (async sockets, IOCP, etc) then it's a bit more work as the examples don't tend to show these things. I wrote an article for Windows Developer Magazine back in 2002 which is available here which shows how to use OpenSSL with async sockets and this code can be used to work with overlapped I/O and IOCP based servers if you need to.