I use wininet to connect to ftp server, i see that wininet only gives true:false for each command that is used to communicate with the server and the classic GetLastError() to get the specific error if any.
What i cant find with wininet is how to get responses from the ftp server whithout sending commands like a stand by mode, i cant find the way if the server choose to disconect me or timeout my session how to get back that response from the ftp server so i can know what is going on with the connection and do the appropiate actions after each response.
Anyone knows ?
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Suppose, UI is making calls to rest service and the server stops.
Does UI come to know about the server's state?
Does UI get any response back from the server?
What difference does it make if the rest call was POST or PUT?
When REST Api is stopped,the UI/Browser/Client will show "Could not get any response
There was an error connecting to " error, irrespective of request type: PUT /POST.
To answer your questions :
Does UI come to know about the server's state?
If Server stops, you will get an error like : error connecting server. Which can be traced to multiple rootcauses. One of them can be : Server has stopped.
In case of error, Server's state can be sent to client using various error codes like:
500 Internal Server Error The 500 status code, or Internal Server Error, means that server cannot process the request for an unknown reason. Here is list of status codes for REST APis: https://www.w3.org/Protocols/HTTP/HTRESP.html
Does UI get any response back from the server?
If server is stopped, UI/Client will receive no response.
What difference does it make if the rest call was POST or PUT?
If the server has stopped, it doesn't make any difference.
You can run this scenario using a browser and running any app/REST service in your local machine.
(For this test you need not have any REST application running in your local, as you only want to test when it is stopped)
For instance, if your REST application server is up and available at port 8080, you can send request to this server by sending request form your browser : http://localhost:8080
For testing with POST/PUT collections, you can use any API Development tools like : Postman.
Let's assue your REST Api , exposes following urls :
/myPostRequest POST
/myPutRequest PUT
When you hit these urls from POSTMAN you get the same response :
POST http://localhost:8080/myPostRequest :
Could not get any response
There was an error connecting to http://localhost:8080/transition-order.
PUT http://localhost:8080/myPutRequest :
Could not get any response
There was an error connecting to http://localhost:8080/transition-order.
Client(could be UI) and Server are two dumb applications. They do and say what they are told to.
So whenever a client tries to call a server on a socket and there is no server listening to it, there is no response returned to the client. The client can interpret it in whatever way it wants. Most of the browsers show <host> refused to connect.
But if a server is listening to a socket, it responds to the client whichever way it was programmed to do. The server sends an appropriate status code and expects that the client knows how to interpret it. A server can send any random number it wants... the catch is, the client must know how to interpret it. otherwise, it's just one-way communication.
In order to provide smooth client-server communication, section 10 of RFC 2616 defines various codes with specific meaning as shown here: https://developer.mozilla.org/en-US/docs/Web/HTTP/Status
These status codes are the same for all the types of Http methods.
I've scenario where ftp client and server are separe with a proxy server.
I want to insert ip source address into ftp client payload so that the ftp server can retrieve it.
The problem is that i don't know how to proceed.
Help me out please.
With regards.
FTP is text-based protocol.
If you can re-implement both the client and the server, just make them understand a new command for your purpose.
E.g. you can have the client send a XIP command just after authentication (or even before, if you need):
XIP 203.0.113.0
The server will just parse the IP and respond something like this (to follow the FTP specification):
200 OK
And then carry on as in a normal FTP session.
I'm running a local web server written in Go and I can debug traffic going to it from my browser; but, I can't see the http request that it makes to external services.
Do I have to run some particular configuration of the web server in order to get the traffic to appear in fiddler? It is running as a background process.
Short answer: you can't...
...unless your web application is written to open a connection to a Proxy server and route requests through that connection (e.g. connect to a remote proxy, and then send requests through it).
Typically what developers do is just dump the Web Request/Response to a debug file to inspect during development (or to debug on a live server, by enabling it with a flag at runtime).
Fiddler is a "proxy" service/server. When you are using it normally to debug browser requests, your Browser is configured to connect to a Proxy server. That is, it will send all web requests through your fiddler's local server (I think it's localhost:8888 if i remember from my Windows days of using Fiddler) which in turn makes a connection to your local web server that you are debugging.
You can read more about Proxies at Wikipedia.
In that picture above, your local web server would be Alice. Meaning, Alice would need to be configured to connect to a proxy server and then make web requests through it.
EDIT:
(for the "I really need this" crowd)
If you really want to modify your web server to send requests through a proxy, there are a few Go packages already written to help you. GoProxy is one such package.
Is it possible to use browser's internet connection for other application?
I'm in environment where browser is the only application that may access internet connection. Meanwhile, I need to run maven projects which needs internet access to download the required JARs.
I was thinking about creating Proxy Server in Chrome extensions or other browser. But, I hope I can find another easier way.
Sounds like Selenium WebDriver is what you need. You could try to redirect the download to browser or try to programmatically simulate browser.
Yes it is possible.
Recently I created a http_proxy server in Java which start 3 socket servers:
Http server to receive user request, and
WebSocket server to allow Chromium extension to create connection to the http_proxy server.
Http Server to receive response body from Chromium.
So, there will be 3 socket connections:
To receive http user request and send back the content, and
To send the URL requested to Chromium browser
When response received by browser (via Xhr), it will do HTTP POST to http_proxy server to send the content.
That's all!
Does anybody know, how to check if broadcast is online or offline in Icecast2 server?
Ruby preferred.
I guess you can make a TCP (HTTP) connection to specified server. Icecast server works as a regular HTTP server but data transfers are actually streams. So, all you need is to make regular Socket connection and send request (you can grab it from live http headers extension in firefox). Also, you might want to set timeout in case that server is down. And if server responds with HTTP/OK (200) code then its live.