This plugin sends a webhook to any URL when a payment is received, sent or forwarded. It supports filtering just some of these events and dispatching the webhooks to multiple URLs (each can have its own filtering policies).
It supports all of the notification types lightningd produces. However, by default it will only dispatch invoice_payment and sendpay_success. The others are available only if you specify them explicitly in the URL querystring (see below).
The payload sent for each webhook is the inner object of the payload given by lightningd. For example, for invoice_payment it will be {"label": "unique-label-for-invoice", "preimage": "0000000000000000000000000000000000000000000000000000000000000000", "msat": "10000msat" }.
This is distributed as a single binary for your delight (or you can compile it yourself with go get).
Download it, call chmod +x <binary> and put it in ~/.lightning/plugins (create that directory if it doesn't exist).
You only need the binary you can get in the releases page, nothing else.
Initialize lightningd passing the option --webhook=https://your.url/here and that's it. You can also write that in your ~/.lightning/config file. A nice place to get webhook endpoints for a quick test is https://beeceptor.com/.
To dispatch webhooks to multiple URLs, write them separated by commas, like --webhook=https://first.url/,https://second.url/.
You can opt to receive only payment, invoice or forward events. To filter (in each URL) append a querystring parameter like ?filter-event=invoice to the URL. You can repeat that parameter. If no parameters are given, invoice_payment and sendpay_success events will be dispatched.
With the following line in ~/.lightning/config:
webhook=https://myurl.com/myhandler?filter-event=invoice_payment
You'll get payloads like these:
{
"invoice_payment": {
"label": "unique-label-for-invoice",
"preimage": "0000000000000000000000000000000000000000000000000000000000000000",
"msat": "10000msat"
}
}