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    name: "examples.webhook_file"
    description: "Sample rule dumping webhook payload to a file."
    enabled: true

    trigger:
        type: "core.st2.webhook"
        parameters:
            url: "sample"

    criteria:
        trigger.payload_parameter_name: # вот этот момент темный лес.
            pattern: "st2"
            type: "equals"

    action:
        ref: "core.local"
        parameters:
            cmd: "echo \"{{trigger.body}}\" >> /tmp/st2.webhook_sample.out"