Added plugin interface definations

- Added wip plugin interface
- Merged in PR for lego update
- Minor code optimization

src/mod/plugins/lifecycle.go

@@ -0,0 +1,67 @@
+package plugins
+
+import (
+	"encoding/json"
+	"errors"
+	"os/exec"
+	"path/filepath"
+)
+
+func (m *Manager) StartPlugin(pluginID string) error {
+	plugin, ok := m.LoadedPlugins.Load(pluginID)
+	if !ok {
+		return errors.New("plugin not found")
+	}
+
+	//Get the plugin Entry point
+	pluginEntryPoint, err := m.GetPluginEntryPoint(pluginID)
+	if err != nil {
+		//Plugin removed after introspect?
+		return err
+	}
+
+	//Get the absolute path of the plugin entry point to prevent messing up with the cwd
+	absolutePath, err := filepath.Abs(pluginEntryPoint)
+	if err != nil {
+		return err
+	}
+
+	//Prepare plugin start configuration
+	pluginConfiguration := ConfigureSpec{
+		Port:         getRandomPortNumber(),
+		RuntimeConst: *m.Options.SystemConst,
+	}
+	js, _ := json.Marshal(pluginConfiguration)
+
+	cmd := exec.Command(absolutePath, "-configure="+string(js))
+	cmd.Dir = filepath.Dir(absolutePath)
+	if err := cmd.Start(); err != nil {
+		return err
+	}
+
+	// Store the cmd object so it can be accessed later for stopping the plugin
+	plugin.(*Plugin).Process = cmd
+	plugin.(*Plugin).Enabled = true
+	return nil
+}
+
+// Check if the plugin is still running
+func (m *Manager) PluginStillRunning(pluginID string) bool {
+	plugin, ok := m.LoadedPlugins.Load(pluginID)
+	if !ok {
+		return false
+	}
+	return plugin.(*Plugin).Process.ProcessState == nil
+}
+
+// BlockUntilAllProcessExited blocks until all the plugins processes have exited
+func (m *Manager) BlockUntilAllProcessExited() {
+	m.LoadedPlugins.Range(func(key, value interface{}) bool {
+		plugin := value.(*Plugin)
+		if m.PluginStillRunning(value.(*Plugin).Spec.ID) {
+			//Wait for the plugin to exit
+			plugin.Process.Wait()
+		}
+		return true
+	})
+}