We used the instructions on GitHub https://github.com/xmatters/xm-labs-sentry to set up the Sentry integration. I am not familiar with Sentry at all and do not have access to it, so am relying on our Sentry admin. She has created several test alerts and most of them have been received by xMatters. I can see the payloads. A couple of alerts were not received. I do not know exactly what she is doing and do not know why some alerts are not received. For the ones that make it to xMatters, the payloads do not have all of the fields the xMatters script is looking for. One alert had a huge payload. The header did not include the name 'sentry-hook-resource' so there was nothing in the output fields. Another alert did include 'sentry-hook-resource' but the value was 'issue'. The script is looking for 'event_alert'. The payload was much smaller and did not include most of the fields the script is looking for.
So is this a problem with the Sentry set up? Is she not creating the right type of alert? Does the xMatters script need to be modified because it is outdated? She said Sentry has changed a bit from the time the documentation was written, and their webhook is now considered legacy.