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# support
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Andreas

03/06/2023, 1:56 PM
i'm trying to forward every exception signoiz receives from my rails app to my mattermost instance via webhooks. i've set up the alert channel, and now should set up an alert query. i started via alerts > new alert > exceptions-based alert. i only have the option of clickhouse query. QueryBuilder is greyed out, PromQL is not an option at all (was mentioned in the docs) i'm baffled by what to do next. i understand that i need to query clickhouse in order to trigger the alert, but i kind of want an all-forward rule. could anybody help me on how to go about doing that?
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Amol Umbark

03/06/2023, 3:40 PM
@Andreas the common use case for alerts is for scenarios like to sum up the errors and get notified when error count is too high or too low. this setup may be a bit experimental i would suggest grouping exceptions by error count for 5 mins and then send the details as labels you would have to write a clickhouse query. The ch queries for alerts require a value and interval column. in this case the value can be count of records and interval can be 5 mins set the alert condition to threshold above or equal to 1 in total for last 5 mins the select can have additional columsn apart from value and interval. these columns will be sent as labels
let me share a sample query
@Andreas More details on this: I would recommend using short window in the alert. Last 5 mins (screenshot of conditions attached). This is a sample query you can work with. It groups exceptions by interval of 1 minute. Also adds a limit, this is to ensure some rate limits. I would recommend to keep it on the lower side ~100 and experiment from there
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SELECT
    count() AS value,
    toStartOfInterval(timestamp, toIntervalMinute(1)) AS interval,
    serviceName,
    exceptionMessage,
    exceptionType
FROM signoz_traces.distributed_signoz_error_index_v2
WHERE  timestamp BETWEEN {{.start_datetime}} AND {{.end_datetime}}
GROUP BY
    serviceName,
    interval,
    exceptionMessage,
    exceptionType
LIMIT 100
Use the same conditions in the attached screenshot. You would see the following kind of webhook message.
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{
      "status": "firing",
      "labels": {
        "additionalInfo": "The rule threshold is set to 0.0000, and the observed metric value is 2.",
        "alertname": "testexceptions_TEST_ALERT",
        "details": "http://<signoz-url>/exceptions",
        "exceptionMessage": "HTTPSConnectionPool(host='xxx', port=443): Max retries exceeded with url: /v3/xxxxx (Caused by NewConnectionError('<urllib3.connection.HTTPSConnection object at 0x10f8970d0>: Failed to establish a new connection: [Errno 8] nodename nor servname provided, or not known'))",
        "exceptionType": "ConnectionError",
        "ruleId": "testexceptions",
        "ruleSource": "http://<sgnoz-url>/alerts/edit?ruleId=testexceptions",
        "serviceName": "flaskApp",
        "severity": "warning"
      },
      "startsAt": "2023-03-07T06:52:49.022196837Z",
      "endsAt": "2023-03-07T06:56:49.022196837Z",
      "fingerprint": "221f269939452105"
    },
The messages may be repeated as rules engine same message with "firing" and then "resolved" status. In your case, the status wouldnt be useful. I would recommend just looking at "firing" status. Also use the fingerprint in the message to identify if this is a new record or an older one. As you can see the exceptionType, exceptionMessage will show up in label section of the message. Do share your use case, so I can help you further
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