port-utils: Utilities for creating and waiting on ports

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Utilities for creating and waiting on ports.

openFreePort will create a socket bound to a random free port will warp's openFreePort

wait will attempt to connect to given host and port until successful.

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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-utilities#readme
Bug tracker https://github.com/jfischoff/port-utilities/issues
Source repo head: git clone https://github.com/jfischoff/port-utilities
Uploaded by JonathanFischoff at 2018-11-02T07:23:41Z
Distributions LTSHaskell:, NixOS:, Stackage:
Downloads 4471 total (33 in the last 30 days)
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Status Docs available [build log]
Last success reported on 2018-11-02 [all 1 reports]

Readme for port-utils-

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This is another version of warp's openFreePort function. Nice if you don't already depend on warp.

openFreePort returns a socket on 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 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 above was copied from this stackoverflow answer https://stackoverflow.com/a/50008755