helperbot/cmd/helper_plugin.go

package main

import (
	"fmt"
	"io/ioutil"
	"os"
	"plugin"
	"strings"

	"git.bullercodeworks.com/brian/helperbot"
)

type HelperPlugin struct {
	p *plugin.Plugin

	State helperbot.PluginState
}

func (a *App) LoadPluginsFromDirectory(dir string) error {
	fmt.Println("Loading Plugins (", dir, ")")
	files, err := ioutil.ReadDir(dir)
	if err != nil {
		fmt.Println("Error loading plugins")
		fmt.Println(err.Error())
		os.Exit(1)
	}
	for _, f := range files {
		if !strings.HasSuffix(f.Name(), ".so") {
			fmt.Printf("Skipping file (%s)\n", f.Name())
			continue
		}
		p, err := plugin.Open(dir + f.Name())
		if err != nil {
			fmt.Println(fmt.Sprintf("Error loading plugin (%s)\n", f.Name()))
			fmt.Println(err.Error())
			os.Exit(1)
		}
		hp, err := NewHelperPlugin(p)
		if err != nil {
			fmt.Println(fmt.Sprintf("Error loading plugin (%s)\n", f.Name()))
			fmt.Println(err.Error())
			os.Exit(1)
		}
		hp.State.Initialize(a.m)
		hp.State.Run()
		fmt.Printf("Plugin Loaded (%s)\n", f.Name())
		a.plugins = append(a.plugins, *hp)
	}
	return nil
}

func NewHelperPlugin(p *plugin.Plugin) (*HelperPlugin, error) {
	h := &HelperPlugin{
		p: p,
	}

	// Parse the plugin's state
	pluginStateSymbol, err := p.Lookup("State")
	if err != nil {
		return nil, err
	}
	h.State = pluginStateSymbol.(helperbot.PluginState)
	return h, nil
}