Front end scripts
Front end scripts are inline in the fast path.
Because frontend scripts are in the fast path. You need to use 
T.async methods to perform I/O in a separate slow path provided by the Trisul framework.List of frontend script types
You can hook your lua scripts into the following points in the frontend.
| Name | Called when | Notes | 
|---|---|---|
| countergroup | During initialization | Create a new counter group | 
| simplecounter | Each packet | Inspect packet contents and update meter/alerts | 
| flowmonitor | When interesting data is seen per flow | Inspect HTTP headers, TLS certs, then attach counters to flows | 
| fileextract | Events in HTTP layer | Flexible platform to extract files transferred via HTTP | 
| reassembly | TCP reassembly | Control and process output from Trisul’s TCP reassembly engine |