Webhook customize

[PaddyPat]

Hi,

i would like to send webhook requests to ntfy. https://docs.ntfy.sh/publish/

is it possible to customize the json file? Because for webhooks I must add a secret, a topic , title .. and so on. https://docs.ntfy.sh/publish/#publish-as-json

Otherwise could I execute a shell cmd with variables ( message or topic or other fields like pid, title, date)?

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