pyfcstm 0.2.0

A Python framework for parsing finite state machine DSL and generating executable code in multiple target languages.

pyfcstm

A Python framework for parsing finite state machine DSL and generating executable code in multiple target languages.

Installation

You can simply install it with pip command line from the official PyPI site.

pip install pyfcstm

For more information about installation, you can refer to Installation Documentation.

How To Use It

Use With CLI

You can use this with CLI command

pyfcstm --help

• Generate Plantuml Code For Visualization

pyfcstm plantuml -i test_dsl_code.fcstm

Here is a simple code example, you can try this out

def int a = 0;
def int b = 0x0;
def int round_count = 0;  // define variables
state TrafficLight {
    >> during before {
        a = 0;
    }
    >> during before abstract FFT;
    >> during before abstract TTT;
    >> during after {
        a = 0xff;
        b = 0x1;
    }

    !InService -> [*] :: Error;

    state InService {
        enter {
            a = 0;
            b = 0;
            round_count = 0;
        }

        enter abstract InServiceAbstractEnter /*
            Abstract Operation When Entering State 'InService'
            TODO: Should be Implemented In Generated Code Framework
        */

        // for non-leaf state, either 'before' or 'after' aspect keyword should be used for during block
        during before abstract InServiceBeforeEnterChild /*
            Abstract Operation Before Entering Child States of State 'InService'
            TODO: Should be Implemented In Generated Code Framework
        */

        during after abstract InServiceAfterEnterChild /*
            Abstract Operation After Entering Child States of State 'InService'
            TODO: Should be Implemented In Generated Code Framework
        */

        exit abstract InServiceAbstractExit /*
            Abstract Operation When Leaving State 'InService'
            TODO: Should be Implemented In Generated Code Framework
        */

        state Red {
            during {  // no aspect keywords ('before', 'after') should be used for during block of leaf state
                a = 0x1 << 2;
            }
        }
        state Yellow;
        state Green;
        [*] -> Red :: Start effect {
            b = 0x1;
        };
        Red -> Green effect {
            b = 0x3;
        };
        Green -> Yellow effect {
            b = 0x2;
        };
        Yellow -> Red : if [a >= 10] effect {
            b = 0x1;
            round_count = round_count + 1;
        };
        Green -> Yellow : /Idle.E2;
        Yellow -> Yellow : /E2;
    }
    state Idle;

    [*] -> InService;
    InService -> Idle :: Maintain;
    Idle -> Idle :: E2;
    Idle -> [*];
}

• Generate Code With Given Template

pyfcstm generate -i test_dsl_code.fcstm -t template_dir/ -o generated_code_dir/

Use With Pythonic API

You can use this with pythonic API.

from pyfcstm.dsl import parse_with_grammar_entry
from pyfcstm.model.model import parse_dsl_node_to_state_machine
from pyfcstm.render import StateMachineCodeRenderer

if __name__ == '__main__':
    # Load AST Node From DSL Code
    ast_node = parse_with_grammar_entry("""
    def int a = 0;
    def int b = 0x0;
    def int round_count = 0;  // define variables
    state TrafficLight {
        state InService {
            enter {
                a = 0;
                b = 0;
                round_count = 0;
            }
            
            enter abstract InServiceAbstractEnter /*
                Abstract Operation When Entering State 'InService'
                TODO: Should be Implemented In Generated Code Framework
            */
            
            // for non-leaf state, either 'before' or 'after' aspect keyword should be used for during block
            during before abstract InServiceBeforeEnterChild /*
                Abstract Operation Before Entering Child States of State 'InService'
                TODO: Should be Implemented In Generated Code Framework
            */
            
            during after abstract InServiceAfterEnterChild /*
                Abstract Operation After Entering Child States of State 'InService'
                TODO: Should be Implemented In Generated Code Framework
            */
            
            exit abstract InServiceAbstractExit /*
                Abstract Operation When Leaving State 'InService'
                TODO: Should be Implemented In Generated Code Framework
            */
        
            state Red {
                during {  // no aspect keywords ('before', 'after') should be used for during block of leaf state
                    a = 0x1 << 2;
                }
            }
            state Yellow;
            state Green;
            [*] -> Red :: Start effect {
                b = 0x1;
            };
            Red -> Green effect {
                b = 0x3;
            };
            Green -> Yellow effect {
                b = 0x2;
            };
            Yellow -> Red : if [a >= 10] effect {
                b = 0x1;
                round_count = round_count + 1;
            };
        }
        state Idle;
        
        [*] -> InService;
        InService -> Idle :: Maintain;
        Idle -> [*];
    }
    """, entry_name='state_machine_dsl')
    # Load DSL Model From DSL AST Node
    model = parse_dsl_node_to_state_machine(ast_node)

    # Load Template Directory
    renderer = StateMachineCodeRenderer(
        template_dir='../fsm_generation_template'
    )
    # Render to Given Directory Via Template Directory
    renderer.render(model, 'test_output_x')

For more information about this DSL, see: PyFCSTM DSL Syntax Tutorial.