[Twisted-Python] Twisted Client
Hi all, I'm writing a simple client / server application, that uses a small protocol to dialog. I can't find in documentation any exemple that would correspond to what my client is supposed to do. Here is the basics : every X seconds, call a function that check a file if file is different, connect to server When the client is connected, it immediatly sends data to server, using the connectionMade method. Do I need to use while(1) loop or loopingCall ? What is the best way to write a daemon that connect to a server every X seconds ? Many thanks.
On Tue, Nov 10, 2009 at 7:25 AM, morbidux <morbidux@free.fr> wrote:
Hi all,
I'm writing a simple client / server application, that uses a small protocol to dialog.
I can't find in documentation any exemple that would correspond to what my client is supposed to do.
Here is the basics :
every X seconds, call a function that check a file if file is different, connect to server
When the client is connected, it immediatly sends data to server, using the connectionMade method.
Do I need to use while(1) loop or loopingCall ? What is the best way to write a daemon that connect to a server every X seconds ?
Many thanks.
A while loop will probably block your application. Use loopingCall (or even callLater, if you want). Here's an example: http://www.saltycrane.com/blog/2008/10/running-functions-periodically-using-... Kevin Horn
On Tue, Nov 10, 2009 at 11:27 AM, Kevin Horn <kevin.horn@gmail.com> wrote:
On Tue, Nov 10, 2009 at 7:25 AM, morbidux <morbidux@free.fr> wrote:
Hi all,
I'm writing a simple client / server application, that uses a small protocol to dialog.
I can't find in documentation any exemple that would correspond to what my client is supposed to do.
Here is the basics :
every X seconds, call a function that check a file if file is different, connect to server
When the client is connected, it immediatly sends data to server, using the connectionMade method.
Do I need to use while(1) loop or loopingCall ? What is the best way to write a daemon that connect to a server every X seconds ?
Many thanks.
What platform? For linux you could do away with the polling and use the python bindings to inotify. On OSX there are bindings to FSEvent API. Much better than a polling solution. -- Jarrod Roberson 678.551.2852
On 11/10/09 6:25 AM, morbidux wrote:
Hi all,
I'm writing a simple client / server application, that uses a small protocol to dialog.
I can't find in documentation any exemple that would correspond to what my client is supposed to do.
Here is the basics :
every X seconds, call a function that check a file if file is different, connect to server
When the client is connected, it immediatly sends data to server, using the connectionMade method.
Do I need to use while(1) loop or loopingCall ? What is the best way to write a daemon that connect to a server every X seconds ?
You could setup a LoopingCall that calls your file checking function. Your file checking function can then use twisted.internet.protocol.ClientCreator to send your data. A simple example: import os from twisted.internet import reactor from twisted.internet.protocol import Protocol, ClientCreator from twisted.internet.task import LoopingCall from twisted.python import log def gotProtocol(p, data): p.transport.write(data) p.transport.loseConnection() def errHandler(reason): log.err(reason) def checkFile(): if os.path.exists('sentry.file'): c = ClientCreator(reactor, Protocol) c.connectTCP("localhost", 1234).addCallback(gotProtocol, 'some data').addErrback(errHandler) lp = LoopingCall(checkFile) lp.start(5, now=True) reactor.run() -- If you want to maintain state between protocol instances, then create a ClientFactory. You could look at how ReconnectingClientFactory is implemented for ideas. The Writing Clients howto should help: http://twistedmatrix.com/projects/core/documentation/howto/clients.html Lucas Taylor
Many thanks for your solution. I've implemented it with success. Best regards. | On 11/10/09 6:25 AM, morbidux wrote: |> Hi all, |> |> I'm writing a simple client / server application, that uses a small |> protocol to dialog. |> |> I can't find in documentation any exemple that would correspond to what |> my |> client is supposed to do. |> |> Here is the basics : |> |> every X seconds, call a function that check a file |> if file is different, connect to server |> |> When the client is connected, it immediatly sends data to server, using |> the connectionMade method. |> |> Do I need to use while(1) loop or loopingCall ? What is the best way to |> write a daemon that connect to a server every X seconds ? |> | | You could setup a LoopingCall that calls your file checking function. | Your file checking function can then use | twisted.internet.protocol.ClientCreator to send your data. | | A simple example: | | import os | from twisted.internet import reactor | from twisted.internet.protocol import Protocol, ClientCreator | from twisted.internet.task import LoopingCall | from twisted.python import log | | def gotProtocol(p, data): | p.transport.write(data) | p.transport.loseConnection() | | def errHandler(reason): | log.err(reason) | | def checkFile(): | if os.path.exists('sentry.file'): | c = ClientCreator(reactor, Protocol) | c.connectTCP("localhost", 1234).addCallback(gotProtocol, 'some | data').addErrback(errHandler) | | lp = LoopingCall(checkFile) | lp.start(5, now=True) | | reactor.run() | | -- | | If you want to maintain state between protocol instances, then create a | ClientFactory. You could look at how ReconnectingClientFactory is | implemented for ideas. | | The Writing Clients howto should help: | http://twistedmatrix.com/projects/core/documentation/howto/clients.html | | | Lucas Taylor | | _______________________________________________ | Twisted-Python mailing list | Twisted-Python@twistedmatrix.com | http://twistedmatrix.com/cgi-bin/mailman/listinfo/twisted-python | | |
participants (4)
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Jarrod Roberson -
Kevin Horn -
Lucas Taylor -
morbidux