Pygaljs

Common errors

• ModuleNotFoundError: No module named 'pygaljs'

  cause The `pygaljs` package is not installed in the active Python environment.
  fix Run `pip install pygaljs` in your terminal to install the package.

• Attempting to create a chart like: pygaljs.Line().add('series', [1, 2, 3]) results in AttributeError: module 'pygaljs' has no attribute 'Line'

  cause `pygaljs` is an asset package for a JavaScript library, not a Python charting API. It does not expose charting classes or functions directly.
  fix Use the `pygal` Python library (note: `pygal` not `pygaljs`) for generating SVG charts from Python, or use `pygal.js` (the JavaScript library) on the frontend if you are serving its assets via `pygaljs`.

Warnings

• gotcha Pygaljs provides assets for a JavaScript library (`pygal.js`), it is not a Python charting library itself. You cannot create charts directly by calling functions from `pygaljs` in Python.
  Fix: If you intend to generate charts directly in Python, consider libraries like `pygal` (the Python charting library) or `matplotlib`, `plotly`, etc. `pygaljs` is for providing the frontend assets if you're using `pygal.js` in a web context.
• gotcha The exact subdirectory structure where `pygal.js` assets (JavaScript, CSS) are stored within the `pygaljs` package might not be immediately obvious or explicitly documented. This can lead to issues when configuring static file serving in web frameworks.
  Fix: Inspect the installed `pygaljs` package directory (e.g., `os.path.dirname(pygaljs.__file__)`) to confirm the asset layout. Common subdirectories are 'static' or a direct package subfolder with the library name, like 'pygaljs/pygaljs/'.

Install

• pip install pygaljs Install with pip

Imports

• pygaljs

  import pygaljs

  The primary import is for the top-level package. Individual charting components are not imported from here as pygaljs provides static assets for a JavaScript library, not a Python charting API.

Quickstart

The `pygaljs` library is primarily an asset provider for the `pygal.js` JavaScript charting library. The most common 'use case' in Python code is to programmatically locate the installation path of these static assets so that a web framework can serve them. This example demonstrates how to find the root directory of the installed package and a likely location for its JavaScript and CSS files.

import os
import pygaljs

# The pygaljs package primarily provides static assets.
# Its main utility in Python code is often to determine the path
# to these assets for serving them in a web framework.

# Get the base directory of the installed pygaljs package
package_root = os.path.dirname(pygaljs.__file__)
print(f"Pygaljs package root: {package_root}")

# Example of how you might construct a path to a specific asset (e.g., JavaScript file)
# Note: The exact subdirectory structure depends on the pygal.js assets it bundles.
# A common pattern for such packages is to have a 'static' or 'dist' directory.

# This path might vary; typically, you'd look for a 'static' or 'dist' folder.
# For pygaljs, the assets are often directly under 'pygaljs/pygaljs/'.
# Checking the GitHub repository (https://github.com/ionelmc/python-pygaljs)
# shows assets like 'pygal-2.0.x.min.js' directly under 'pygaljs/pygaljs'.

pygaljs_assets_dir = os.path.join(package_root, 'pygaljs')
print(f"Pygaljs assets directory (potential): {pygaljs_assets_dir}")

# Verify if the directory exists and list some contents (for demonstration)
if os.path.exists(pygaljs_assets_dir):
    print("Contents of pygaljs assets directory (first 5 files):")
    for i, item in enumerate(os.listdir(pygaljs_assets_dir)):
        if i >= 5: break
        print(f"  - {item}")
else:
    print(f"Warning: {pygaljs_assets_dir} does not exist. Asset location might differ.")

# In a web framework (e.g., Flask, Django), you would configure
# a static file handler to serve files from `pygaljs_assets_dir`.
# For example, in Flask:
# app.static_folder = os.path.join(os.path.dirname(pygaljs.__file__), 'pygaljs')