I'm implementing a simple HTTP client.
Which header should I add to a HTTP 1.1 request so it won't keep alive?
You need to add header: Connection: close. Currently all connections are permanent and client must explicitly claim that it wants to close the connection.
Related
I'm implementing a server that is sending to the client a http keep-alive request but I would like that the client does not make pipelining requests. Is there any flag to tell client to not do multiple pipeline requests?
The keep-alive request seams to work but I don't want pipeline requests.
I would like a sequential request.
No, there is no such flag.
FWIW, with pipelining the requests would still be sequential, you just can get more while still sending a response.
I want to send my response data to to client with "Transfer-Encoding:trunked".
But I do not find the way to do it with Golang.
Is there any example for this?
The net/http server does not allow the application to control the transfer encoding.
The net/http server automatically uses chunked encoding when the application does not set the Content-Length response header and the connection can be reused (http/1 client requested keep-alive or http/1.1 client did not request connection close).
Is it alright to respond with HTTP/1.0 to HTTP/1.1 request?
I am implementing HTTP communication through simple sockets and clients make requests with both HTTP/1.0 and HTTP/1.1 but protocol is independent of HTTP version so I want to always respond with HTTP/1.0 to all requests.
Does HTTP standard bear such communication?
Of course it's alright. Otherwise, if you only supported HTTP/1.0, what could you do?
If HTTP 1.2 came out today, what do you think all existing HTTP 1.1 servers would send as replies to HTTP 1.2 queries? Of course, it'll have to be HTTP 1.1 replies -- that's all they know how to do.
Just make sure you don't follow HTTP 1.1 rules where they differ. For example, keep alives are not enabled by default. If a client sees an HTTP 1.0 reply, it will assume HTTP 1.0 semantics.
By default Connection Header is set to Keep-Alive in browers, to make it possible to keep connection open for further requests from browser.
When I make Connection header to close, what may be the difference ?
Will that affect any performance issue ?
(one addition: I am setting header from xmlhttprequest)
When you make requests with "Connection: keep-alive" the subsequent request to the server will use the same TCP connection. This is called HTTP persistent connection. This helps in reducing CPU load on the server side and improves latency/response time.
If a request is made with "Connection: close" this indicates that once the request has been made the server needs to close the connection. And so for each request a new TCP connection will be established.
By default HTTP 1.1 client/server uses keep-alive whereas HTTP 1.0 client/server doesn't support keep-alive by default.
It affects performance, because most expensive resources create a socket between two machines. So the client needs to establish a new connection in every request.
this article has graphically demonstrated what would happen in such a when the connection header is set to closed and also keep-alive.
It helped me understand it and I hope it helps you too.
The Benefits of Connection Keep Alive
I have a HTTP client that sets the Connection header to the following value when I make a request:
Connection: close
However when the server sends a response, it is setting the header to Keep-Alive:
Connection: Keep-Alive
This seems intuitively wrong to me, and I am wondering how the client should handle such a response from the server? Also why would a server respond with Keep-Alive, when the client has asked for the connection to be closed, is this valid?
According to the HTTP RFC:
"HTTP/1.1 defines the "close" connection option for the sender to signal that the connection will be closed after completion of the response. For example,
Connection: close
in either the request or the response header fields indicates that the connection SHOULD NOT be considered `persistent' (section 8.1) after the current request/response is complete."
That's fine. You are telling the server you don't support persistent connections and it's telling you it does. Either party is completely valid in closing the connection - it's more of a message about what both supports rather then a YOU MUST CLOSE THIS CONNECTION command.
The client says I will close the connection when the current request/response is finished,or in other words , said you don't support persisten connections. That is, it doesn't tell the server to close the connection. The server replies that it supports persistent connections(keep-alive).
As you've told the server that you don't support persistent connection, you should close the connection when you've read the response.