mermaid rendering - chunhualiao/public-docs GitHub Wiki
https://huggingface.co/spaces/liaoch/mermaid-rendering
sometimes I just want to render them myself
#!/usr/bin/env python3
# Instructions to install dependencies and run the program:
#
# 1. Install Node.js:
# - Download and install Node.js from https://nodejs.org/
# - Verify installation by running `node --version` in your terminal.
#
# 2. Install the Mermaid CLI (@mermaid-js/mermaid-cli):
# - Run `npm install -g @mermaid-js/mermaid-cli` in your terminal.
# - If you encounter permissions issues, you might need to use `sudo` (for macOS/Linux)
# or run the command prompt as an administrator (for Windows).
# - Verify installation by running `mmdc --version`.
#
# 3. Run the script:
# - You can run the script directly with the embedded example by uncommenting the lines in the `if __name__ == "__main__":` block and running:
# `python3 mermaid-rendering.py`
# - Alternatively, you can use the command-line interface:
# - To render Mermaid code from a string:
# `python3 mermaid-rendering.py -c "your_mermaid_code"`
# - To render Mermaid code from a file:
# `python3 mermaid-rendering.py -f /path/to/your/file.mmd`
# - You can specify the output file with `-o /path/to/output.png`, output type with `-t [png, pdf, svg]`, and theme with `--theme [default, forest, dark, neutral]`.
# - For example:
# `python3 mermaid-rendering.py -f input.mmd -o output.png -t png --theme default`
import os
import sys
import subprocess
import argparse
import tempfile
import json
from pathlib import Path
import textwrap
class MermaidRenderer:
"""
A Python class to render Mermaid diagrams to various formats
using puppeteer-mermaid behind the scenes
"""
def __init__(self):
"""Initialize the renderer and check if dependencies are installed"""
self._check_dependencies()
def _check_dependencies(self):
"""Check if Node.js and puppeteer-mermaid are installed"""
try:
# Check for Node.js
subprocess.run(["node", "--version"], capture_output=True, check=True)
except (subprocess.SubprocessError, FileNotFoundError):
sys.exit("Error: Node.js is not installed. Please install Node.js from https://nodejs.org/")
# Check if @mermaid-js/mermaid-cli is installed
result = subprocess.run(["npm", "list", "-g", "@mermaid-js/mermaid-cli"],
capture_output=True, text=True)
if "mermaid-cli" not in result.stdout:
print("Installing @mermaid-js/mermaid-cli globally...")
try:
subprocess.run(["npm", "install", "-g", "@mermaid-js/mermaid-cli"], check=True)
print("@mermaid-js/mermaid-cli installed successfully.")
except subprocess.SubprocessError:
sys.exit("Error: Failed to install @mermaid-js/mermaid-cli. Please install manually using: npm install -g @mermaid-js/mermaid-cli")
def render(self, mermaid_code, output_file=None, output_format="png", theme="default"):
"""
Render Mermaid code to the specified format
Args:
mermaid_code (str): The Mermaid diagram code
output_file (str, optional): Output file path. If None, generates a filename based on format.
output_format (str, optional): Output format. Options: png, pdf, svg. Default: png
theme (str, optional): Mermaid theme. Default: default
Returns:
str: Path to the generated file
"""
# Validate output format
valid_formats = ["png", "pdf", "svg"]
if output_format not in valid_formats:
sys.exit(f"Error: Invalid output format. Choose from: {', '.join(valid_formats)}")
# Create a temporary file for the Mermaid code
with tempfile.NamedTemporaryFile(mode='w', suffix='.mmd', delete=False) as temp_file:
temp_file.write(mermaid_code)
input_path = temp_file.name
# Generate output file name if not provided
if not output_file:
output_file = f"diagram.{output_format}"
# Ensure output directory exists
output_dir = os.path.dirname(output_file)
if output_dir:
os.makedirs(output_dir, exist_ok=True)
# Run puppeteer-mermaid
try:
cmd = [
"mmdc",
"-i", input_path,
"-o", output_file,
"-t", theme,
"-f", output_format
]
subprocess.run(cmd, check=True)
print(f"Diagram saved to: {output_file}")
# Clean up the temporary file
os.unlink(input_path)
return output_file
except subprocess.SubprocessError as e:
os.unlink(input_path)
sys.exit(f"Error rendering diagram: {str(e)}")
def main():
"""Command line interface for the Mermaid renderer"""
parser = argparse.ArgumentParser(description="Render Mermaid diagrams to PNG, PDF, or SVG.")
input_group = parser.add_mutually_exclusive_group(required=True)
input_group.add_argument("-c", "--code", help="Mermaid code as a string")
input_group.add_argument("-f", "--file", help="Path to a file containing Mermaid code")
parser.add_argument("-o", "--output", help="Output file path")
parser.add_argument("-t", "--type", default="png", choices=["png", "pdf", "svg"],
help="Output file type (default: png)")
parser.add_argument("--theme", default="default",
choices=["default", "forest", "dark", "neutral"],
help="Mermaid theme (default: default)")
args = parser.parse_args()
# Get Mermaid code from string or file
if args.code:
mermaid_code = args.code
else:
try:
with open(args.file, 'r') as f:
mermaid_code = f.read()
except (IOError, FileNotFoundError):
sys.exit(f"Error: Could not read file {args.file}")
# Create renderer and render the diagram
renderer = MermaidRenderer()
renderer.render(mermaid_code, args.output, args.type, args.theme)
# Example usage with multiline string for easy copy-paste
if __name__ == "__main__":
# You can replace this multiline string with your own Mermaid diagram code
MERMAID_CODE = """
pie title NETFLIX
"Time spent looking for movie" : 90
"Time spent watching it" : 10
"""
# Uncomment and modify these lines to run directly
renderer = MermaidRenderer()
renderer.render(MERMAID_CODE, "flowchart.svg", "svg", "default")
renderer.render(MERMAID_CODE, "flowchart.pdf", "pdf", "default")
# Or use the command-line interface
#main()