port-utils: Utilities for creating and waiting on ports

[ bsd3, library, unclassified ] [ Propose Tags ]

Utilities for creating and waiting on ports. . openFreePort will create a socket bound to a random port (like warp's openFreePort). . wait will attempt to connect to given host and port repeatedly until successful. .

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Versions [faq],,,,,,
Change log ChangeLog.md
Dependencies base (>=4.7 && <5), network [details]
License BSD-3-Clause
Copyright 2018 Jonathan Fischoff
Author Jonathan Fischoff
Maintainer jonathangfischoff@gmail.com
Home page https://github.com/jfischoff/port-utils#readme
Bug tracker https://github.com/jfischoff/port-utils/issues
Source repo head: git clone https://github.com/jfischoff/port-utils
Uploaded by JonathanFischoff at 2019-04-27T20:42:03Z
Distributions LTSHaskell:, NixOS:, Stackage:
Downloads 2891 total (166 in the last 30 days)
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Status Hackage Matrix CI
Docs available [build log]
Last success reported on 2019-04-27 [all 1 reports]


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Readme for port-utils-

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This is another version of warp's openFreePort function. This function has fewer dependencies than the warp version.

openFreePort returns a socket on a random port and the port it has been bound to.

openFreePort :: IO (Int, Socket)


wait will attempt to connect to a host and port until it is successful. Between each unsuccessful attempt, it sleeps for 10 ms.

Here is an example of the primary function:

import Network.Socket.Wait (wait)

void $ forkIO $ Warp.run 7000 app
-- Wait for the server to start listening on the socket
wait "" 7000
-- Communicate with the server

In bash one could write:

while ! nc -z localhost 7000 ; do sleep 0.01 ; done

The bash script above was copied from this stackoverflow answer https://stackoverflow.com/a/50008755