JSON Canvas MCP Server

#!/usr/bin/env python3 """Example script demonstrating how to use the JSON Canvas library.""" import json import os import sys from pathlib import Path # Add the parent directory to the path so we can import the jsoncanvas package sys.path.insert(0, str(Path(__file__).parent.parent)) from jsoncanvas import ( Canvas, TextNode, FileNode, LinkNode, GroupNode, Edge, ) def load_config() -> dict: """Load configuration from config.json. Returns: Dictionary containing configuration values Raises: FileNotFoundError: If config.json doesn't exist KeyError: If required configuration values are missing """ config_path = Path("config.json") if not config_path.exists(): print("Error: config.json not found.") print("Please copy config.json.template to config.json and customize it.") sys.exit(1) with open(config_path) as f: config = json.load(f) # Validate required configuration if "output" not in config: raise KeyError("Missing 'output' section in config.json") if "path" not in config["output"]: raise KeyError("Missing 'path' in output section of config.json") return config def main(): """Create a sample canvas and save it to a JSON file.""" # Load configuration config = load_config() output_path = Path(config["output"]["path"]) # Create nodes title_node = TextNode( id="title", x=100, y=100, width=400, height=100, text="# JSON Canvas Example\n\nThis is a demonstration of the JSON Canvas format.", color="#4285F4" # Google Blue ) file_node = FileNode( id="spec", x=600, y=100, width=300, height=100, file="specification.md", subpath="#nodes", color="2" # Orange preset ) link_node = LinkNode( id="website", x=100, y=300, width=300, height=80, url="https://jsoncanvas.org", color="4" # Green preset ) group_node = GroupNode( id="examples", x=500, y=250, width=400, height=200, label="Example Group", color="6" # Purple preset ) code_node = TextNode( id="code", x=550, y=300, width=300, height=100, text="```python\nprint('Hello, JSON Canvas!')\n```" ) # Create edges title_to_spec = Edge( id="edge1", from_node="title", to_node="spec", from_side="right", to_side="left", color="1" # Red preset ) title_to_website = Edge( id="edge2", from_node="title", to_node="website", from_side="bottom", to_side="top", label="Learn More" ) website_to_group = Edge( id="edge3", from_node="website", to_node="examples", from_side="right", to_side="left" ) # Create canvas and add nodes and edges canvas = Canvas() # Add nodes (order determines z-index) canvas.add_node(group_node) # Add group first so it's in the background canvas.add_node(title_node) canvas.add_node(file_node) canvas.add_node(link_node) canvas.add_node(code_node) # Add edges canvas.add_edge(title_to_spec) canvas.add_edge(title_to_website) canvas.add_edge(website_to_group) # Convert to dictionary and save as JSON canvas_dict = canvas.to_dict() # Create the output directory if it doesn't exist output_path.mkdir(parents=True, exist_ok=True) # Save to a JSON file output_file = output_path / "example.canvas" with open(output_file, "w") as f: json.dump(canvas_dict, f, indent=2) print(f"Canvas saved to {output_file}") # Print the JSON to the console print("\nCanvas JSON:") print(json.dumps(canvas_dict, indent=2)) # Demonstrate loading from dictionary loaded_canvas = Canvas.from_dict(canvas_dict) print("\nSuccessfully loaded canvas from dictionary") print(f"Number of nodes: {len(loaded_canvas.nodes)}") print(f"Number of edges: {len(loaded_canvas.edges)}") if __name__ == "__main__": main()