callstack_callers

Prototype: callstack_callers()

Return type: data

Description: Return the call stack for the current promise.

This is a call stack inspection function and the specific content may be tied to a specific CFEngine version. Using it requires writing code that takes the specific CFEngine version into account.

The returned data container is a list of key-value maps.

The maps all have a type key and a frame key with a counter. For different frames along the stack frame path, the maps have additional keys:

• whenever possible,
• bodies: under key body the entry has a full dump of the body policy as JSON, same as what cf-promises -p json would produce, using the internal C function BodyToJson(). This may include the line and sourcePath to locate the exact code line.
• bundles: under key bundle the entry has a full dump of the bundle policy as JSON, same as what cf-promises -p json would produce, using the internal C function BundleToJson(). This may include the line and sourcePath to locate the exact code line.
• promise iteration: the iteration_index is recorded
• promises: the promise_type, promiser, promise_classes, and promise_comment are recorded
• promise sections (types): the promise_type is recorded

Example:

    vars:
      "stack" data => callstack_callers();

Output:

    [ ... call stack information ... ,
      {
        "depth": 2,
        "frame": 9,
        "promise_classes": "any",
        "promise_comment": "",
        "promise_type": "methods",
        "promiser": "",
        "type": "promise"
      }, ... more call stack information ... ]

History: Introduced in CFEngine 3.9

See also: callstack_promisers()