Simple Flowchart Generator Script

A Python CLI tool to generate flowcharts from structured JSON input, supporting linear and branching workflows. Outputs PNG images using Graphviz.

Features

• Define nodes and edges in JSON format
• Supports common flowchart shapes: oval (start/end), rectangle (process), diamond (decision), parallelogram (input/output)
• Edge labels for conditional branches
• Input validation and error handling
• Command-line interface for easy usage

Requirements

• Python 3.6+
• Graphviz system package installed and in your PATH
• Python graphviz package:

  pip3 install graphviz
  

Usage

1. Create a JSON file describing your flowchart, e.g. flow.json:

{
  "nodes": {
    "start": {"label": "Start", "shape": "oval"},
    "load": {"label": "Select Dataset & Load Data", "shape": "parallelogram"},
    "train": {"label": "Train and Save Model", "shape": "rectangle"},
    "test": {"label": "Load Model & Test Data (by prefix)", "shape": "rectangle"},
    "predict": {"label": "Predict & Explain (LIME + SHAP)", "shape": "rectangle"},
    "display": {"label": "Display Results & Save Plots", "shape": "parallelogram"},
    "end": {"label": "End", "shape": "oval"}
  },
  "edges": [
    {"from": "start", "to": "load"},
    {"from": "load", "to": "train"},
    {"from": "train", "to": "test"},
    {"from": "test", "to": "predict"},
    {"from": "predict", "to": "display"},
    {"from": "display", "to": "end"}
  ]
}

2. Run the tool:

python flowchart_tool.py flow.json output.png

3. Find the generated flowchart in output.png

Error Handling

The tool validates the JSON structure and node references. Errors will be reported if the input is invalid.

Extending

You can customize node shapes and add edge labels for branching logic in the JSON input.

License

MIT License