feat: add googlechat notifier

[tamcore]

This will add a Google Chat notifier and allow existing setups to replace the slightly aged calert with a native integration.

Essentially all that's required is to send a POST with {"text": "our alert"}, so there isn't too much breakage potential :D

• it actually works
• documentation
• tests (sorta)

#2940 2940

[gotjosh]

Nice! Thanks @tamcore - Do you have any stats on downloads/usage over the past 6 months? I can see that it has a decent number of stars but would love to know more about the usage itself.

[tamcore]

Not really. But according to https://github.com/mr-karan/calert/pkgs/container/calert/64363789?tag=v2.0.6 the latest release had 39353 downloads during the 9 months since release.

But there's definitely some interest, and at our company we use it as well (but only one of those 39353 pulls is from us - we use an image cache :D)

• https://2021.openinfra.id/slides/Didiet_A._Pambudiono_-_Sending_Prometheus_Alertmanager_to_Google_Chat.pdf
• https://stackoverflow.com/questions/66333868/send-notification-from-prometheus-alertmanager-to-google-chat-room
• https://groups.google.com/g/prometheus-users/c/p8-O9m7ajqI

[tamcore]

@simonpasquier / @gotjosh any chance to get this included? :)

[uded]

I would like to see this included. Running external service for simple notifications is a pain in the back. This change doesn't look so dramatic, it should be merged relatively easily...

[shivam199064]

It shows the error:
ts=2024-01-18T12:57:51.801Z caller=coordinator.go:126 level=info component=configuration msg="Completed loading of configuration file" file=/etc/alertmanager/config.yml
ts=2024-01-18T12:57:51.806Z caller=cluster.go:692 level=info component=cluster msg="gossip not settled but continuing anyway" polls=0 elapsed=69.811041ms
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0xe28cf1]
goroutine 1 [running]:
github.com/prometheus/alertmanager/notify/googlechat.New(0xc00099a3c0, 0xc0005df398, {0x1612340?, 0xc00020f5e0}, {0x0?, 0x0?, 0x0?})
/root/shivam/alertmanager/notify/googlechat/googlechat.go:44 +0x51
github.com/prometheus/alertmanager/config/receiver.BuildReceiverIntegrations.func15({0x1612340?, 0xc00020f5e0?})
/root/shivam/alertmanager/config/receiver/receiver.go:97 +0x3c
github.com/prometheus/alertmanager/config/receiver.BuildReceiverIntegrations.func1({0x10cf6f5, 0xa}, 0x0, {0x1612900, 0xc00099a3c0}, 0xc000c44958)
/root/shivam/alertmanager/config/receiver/receiver.go:48 +0xe6
github.com/prometheus/alertmanager/config/receiver.BuildReceiverIntegrations({{0xc000b67de0, 0xa}, {0x0, 0x0, 0x0}, {0x0, 0x0, 0x0}, {0x0, 0x0, ...}, ...}, ...)
/root/shivam/alertmanager/config/receiver/receiver.go:97 +0x1030
main.run.func9(0xc000000aa0)
/root/shivam/alertmanager/cmd/alertmanager/main.go:393 +0x5af
github.com/prometheus/alertmanager/config.(*Coordinator).notifySubscribers(...)
/root/shivam/alertmanager/config/coordinator.go:87
github.com/prometheus/alertmanager/config.(*Coordinator).Reload(0xc00057f500)
/root/shivam/alertmanager/config/coordinator.go:131 +0x5b6
main.run()
/root/shivam/alertmanager/cmd/alertmanager/main.go:481 +0x5605
main.main()
/root/shivam/alertmanager/cmd/alertmanager/main.go:125 +0x13

[mehdicopter]

Hey folks 👋
also interested in this feature 😊

[nathanlcarlson]

It looks like something similar to this MSTeams code needs to be added in config/config.go:

https://github.com/prometheus/alertmanager/blob/main/config/config.go#L535-L542