Scripting

Scripting

Frags allows for injecting scripts in certain functionalities, like pre-calls and transformers.

Important: scripting is a sensitive context because it can allow arbitrary code execution. Be extremely careful and totally certain about the context you're using this functionality in. As a default, the Frags library has no scripting functionality enabled, but supports the implementation of one. The CLI tool has JavaScript scripting support making it unsuitable for shared/internet-accessible use.

CLI

In the pre-calls:

preCalls:
  - name: find_stuff
    description: info about the database
    code: |-
      var data = runFunction("find_meta", {"tags": ["database"]})
      data.items;

The presence of the code key indicates that the function is a script. The script has access to the functions and can invoke them using the runFunction function. the same capability is available in transformers.

Go

To implement a scripting engine in Frags, implement the ScriptEngine interface and then assign it to Runner as in:

runner := frags.NewRunner[frags.ProgMap](
			sm,
			frags.NewFileResourceLoader(dir),
			ai,
			frags.WithScriptEngine(NewJavascriptScriptingEngine()),
		)

Again, be very mindful of what you do. This is not a joke.