|Peter J. Jones 597d2858b4 Add a NixOS module to configure webhooks that wait on FIFOs||2 週之前|
Ever wish you could do something custom with all those web hooks offered by various web service providers? This package provides an easy and safe way to do just that.
examples directory there is a script named
download-video.sh. Here is how I use it:
When I want to watch a video later, probably on an airplane, I tag the video in my RSS feed reader (https://feedly.com/).
That triggers an IFTTT applet which uses the IFTTT support for calling a web hook and calls into this package.
This package runs the
download-video.sh script which downloads
the video to a directory that is automatically synced with my
This package includes an executable called
executable can be used to create new hooks from the command line or
run a web server to respond to incoming requests. A hook is just an
indirect way to run a script if you know the hook’s secret code.
For security reasons, the web server does not run scripts directly. Instead, if the incoming request correctly maps to an existing hook, the request data will be appended to an existing file as JSON.
“Okay, but how does appending JSON to a file help me?” you ask. Good question. Thanks to the magic of POSIX named pipes (FIFOs), you can feed that JSON data into a waiting script.
Run the HTTP server provided by this package:
$ webhooks server --port 3000
Create a new web hook that appends to a file. In this example
we’ll configure a hook to append to the file
$ webhooks create --append /tmp/foo.pipe
This command will print a secret code for the newly created hook.
(If you forget the hook’s secret code you can use the
list command to look it up again.)
Run a script that creates the named pipe and then reads lines
from it. In the
examples directory there is a script that will
do this for you and then execute other commands as requests come
in. (The commands receive JSONs request on their stdin.)
$ examples/watchfifo.sh -f /tmp/foo.pipe -- examples/download-video.sh
Use the hook’s secret code to trigger your script. In this
example we’ll pretend that the secret code is
$ curl --data url=https://player.vimeo.com/video/148946917 \ http://localhost:3000/hooks/XXX
This leads to the
download-video.sh script running and being
fed the following JSON:
Ideally, you should run the
webhooks server behind a reverse proxy
that is properly configured for TLS. This will prevent hook codes
from being exposed to the network unencrypted. To encourage this, the
server only binds to the loopback device.
More details about installing and running this package can be found in the installation guide.