Support alerts with missing mandatory attributes

[lindhor]

Prerequisites

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  • Checked that there is not already provided the described functionality

Description

prom2teams should be able to handle incoming messages no matter what attributes are received. For missing attributes that are required in the output, default values should be assigned.

alertname='unknown'
status='firing'
instance='unknown'
summary='no alert summary specified'

The current list of mandatory attributes is too strict, since it for example includes instance which is not always sent.

Steps to Reproduce

Create an absent rule like IF absent(container_cpu_load_average_10s{name='mycriticalcontainer}) (cAdvisor) and the alert sent will not include the attribute instance

Expected behavior:

The alert should be sent with the available attributes filled out.

Actual behavior:

The alert from prom2teams to MS Teams will say Incorrect JSON received. At least one mandatory field (instance) is absent.

Reproduces how often:

All the time.

Versions

1.1.3

Additional Information