Loading Plugins

How to load and manage plugins in your application.

Basic Loading

import pkl
from pathlib import Path

# Create a host
host = pkl.PluginHost()
pkl.set_default_host(host)

# Load a plugin
plugin = pkl.load_plugin(Path("./my_plugin"))

# Enable it
plugin.enable()

# Use it
from pkl.plugins import my_plugin
my_plugin.do_something()

# Disable when done
plugin.disable()

Plugin States

Plugins transition through states:

UNLOADED → LOADED → ENABLED → DISABLED
              ↓
           ERROR

• UNLOADED: Not yet loaded
• LOADED: Code loaded, not running
• ENABLED: Active and running
• DISABLED: Stopped, resources cleaned up
• ERROR: Failed to load/enable

Loading from Different Sources

From Path

plugin = pkl.load_plugin(Path("/path/to/plugin"))

From String Path

plugin = pkl.load_plugin("./plugins/my_plugin")

Plugin Dependencies

Plugins can depend on other plugins:

{
  "name": "my_plugin",
  "requires": ["auth", "database"]
}

Dependencies must be loaded and enabled first:

auth = pkl.load_plugin("./auth")
auth.enable()

db = pkl.load_plugin("./database")  
db.enable()

# Now can load dependent plugin
my_plugin = pkl.load_plugin("./my_plugin")
my_plugin.enable()

Error Handling

try:
    plugin = pkl.load_plugin(path)
    plugin.enable()
except ImportError as e:
    print(f"Failed to load: {e}")
except Exception as e:
    print(f"Failed to enable: {e}")
    print(f"Plugin state: {plugin.state}")

Next Steps

• Resources
• Lifecycle