PDDL-Grounder

A tool that, given as input the domain.pddl and problem.pddl files, generates the grounded translation of the problem

Requirements

• Python version: 3.7 or higher
• Antlr4
• Antlr4 Python3 runtime target
• Click Python Library: Package for creating command line interfaces

Code Overview

• pddl.g4 - The grammar file. It currently supports a simplified version of PDDL+.
  
  For example domain.pddl problem-1.pddl.

• antlr4_directory - The folder generated by antlr4 using the pddl.g4 grammar with the command:

  antlr4 -Dlanguage=python3 pddl.g4 -o antlr4_directory

• grounder.py - The main module

myUtilities Folder

• Domain_parser.py - It contains the functions needed to traverse the parse-tree of the domain generated by the antlr4 parser and to represent the tree in JSON format.
  
  For example domain.json.

• Problem_parser.py - It contains the functions needed to traverse the parse-tree of the problem generated by the antlr4 parser and to represent the tree in JSON format.
  
  For example problem.json.

• Grounding.py - Contains functions for grounding actions, processes, and events of a domain represented in JSON, given a problem represented in JSON. The result is a JSON file.
  
  For example Inputs: domain.json, problem.json Output: grounding_result.json

• Writer.py - Contains the function to write the grounded translation of the domain.pddl file
  
  For example domain_grounded.pddl.

How to use

To run the script simply run the command above, where --domain takes the name of the PDDL domain file and --problem takes the name of the PDDL problem file. These files MUST be present in the PDDL_Files folder.

python grounder.py --domain domain.pddl --problem problem-1.pddl

If some changes to the grammar file pddl.g4 are needed, the new parser and lexer are generated with the command:

antlr4 -Dlanguage=python3 pddl.g4 -o antlr4_directory

Resources

• A grammar that supports more complex domains in PDDL 3 BUT in antlr3
• [PDDL documentation] (https://planning.wiki/)
• A simple PDDL+ domain and some problems
• Online Syntactic Tree Viewer: Very useful during the development phase to graphically visualize the tree generated by the antlr4 parser