Pass State

The Pass class acts as a pass through state, allowing new data to be added, or the input to be filtered.

For more details on Pass, see the AWS documentation.

class awssl.Pass(Name='', Comment='', InputPath='$', OutputPath='$', EndState=False, NextState=None, ResultPath='$', ResultAsJSON=None)

Models the Pass state, which can transfer input to output, or can inject specific values via set_result().

Either:

  • EndState is True and NextState must be None
  • EndState is False and NextState must be a valid instance of a class derived from StateBase.

Values can be returned by Pass by specifying a JSON result for ResultAsJSON such as:

{
        "output": "This is a value"
}

and then using OutputPath to filter, by specifing “$.output”.

Parameters:
  • Name (str) – [Required] The name of the state within the branch of the state machine
  • Comment (str) – [Optional] A comment describing the intent of this pass state
  • InputPath (str) – [Optional] Filter on the Input information to be passed to the Pass state. Default is “$”, signifying that all the Input information will be provided
  • OutputPath (str) – [Optional] Filter on the Output information to be returned from the Pass state. Default is “$”, signifying that all the result information will be provided
  • EndState (bool) – [Optional] Flag indicating if this state terminates a branch of the state machine. Defaults to False.
  • NextState (instance of class derived from StateBase) – [Optional] Next state to be invoked within this branch. Must not be None unless EndState is True.
  • ResultPath (dict) – [Optional] JSONPath indicating where results should be added to the Input. Defaults to “$”, indicating results replace the Input entirely.
  • ResultAsJSON – [Optional] Data to be returned by this state, in JSON format.
clone(NameFormatString='{}')

Returns a clone of this instance, with the clone named per the NameFormatString, to avoid state name clashes.

If this instance is not an end state, then the next state will also be cloned, to establish a complete clone of the branch form this instance onwards.

Parameters:NameFormatString (str) – [Required] The naming template to be applied to generate the name of the new instance.
Returns:Pass – A new instance of this instance and any other instances in its branch.
get_result()

Returns the JSON result of this instance.

Returns:dict – The JSON representation
set_result(ResultAsJSON={})

Sets the result to be returned by this instance of Pass.

Parameters:ResultAsJSON – [Optional] Data to be returned by this state, in JSON format.
to_json()

Returns the JSON representation of this instance.

Returns:dict – The JSON representation
validate()

Validates this instance is correctly specified.

Raises Exception with details of the error, if the state machine is incorrectly defined.