Store plugin parents

internal/core/basis.go

@@ -530,6 +530,50 @@ func (b *Basis) Run(ctx context.Context, task *vagrant_server.Task) (err error)
 	return
 }
 
+type HasParents interface {
+	Parents() ([]string, error)
+}
+
+func (b *Basis) loadParentPlugins(p *plugin.Plugin, typ component.Type) (err error) {
+	plg, err := p.InstanceOf(typ)
+	if err != nil {
+		panic(err)
+	}
+	h, ok := plg.Component.(HasParents)
+	if !ok {
+		b.logger.Debug("Plugin of type ", typ, " does not have Parents")
+		return nil
+	}
+	parents, err := h.Parents()
+	if err != nil {
+		panic(err)
+	}
+	if len(parents) == len(p.ParentPlugins) {
+		return
+	}
+	// TODO: avoid making duplicate entries
+	for _, parent := range parents {
+		// Avoid looping if a plugin name has erronously been added to the parent list
+		if parent == p.Name {
+			continue
+		}
+		b.logger.Debug("Loading parents: ", parent)
+		parentPlugin, err := b.plugins.Find(parent, typ)
+		if err != nil {
+			b.logger.Debug("Error finding parent plugin: ", parent)
+			continue
+		}
+		_, err = parentPlugin.InstanceOf(typ)
+		if err != nil {
+			b.logger.Debug("Error loading parent plugin: ", parent)
+		}
+		p.ParentPlugins = append(p.ParentPlugins, parentPlugin)
+		b.loadParentPlugins(parentPlugin, typ)
+	}
+	p.SetParentPlugins(typ)
+	return
+}
+
 // Load a specific component
 func (b *Basis) component(
 	ctx context.Context, // context for the plugin
@@ -545,6 +589,10 @@ func (b *Basis) component(
 	if err != nil {
 		return nil, err
 	}
+
+	// Make sure parent plugins get loaded
+	b.loadParentPlugins(p, typ)
+
 	c, err := p.InstanceOf(typ)
 	if err != nil {
 		return nil, err

internal/plugin/plugin.go

@@ -34,12 +34,13 @@ var (
 )
 
 type Plugin struct {
-	Builtin  bool                  // Flags if this plugin is a builtin plugin
-	Client   plugin.ClientProtocol // Client connection to plugin
-	Location string                // Location of the plugin (generally path to binary)
-	Name     string                // Name of the plugin
-	Types    []component.Type      // Component types supported by this plugin
-	Cache    cacher.Cache
+	Builtin       bool                  // Flags if this plugin is a builtin plugin
+	Client        plugin.ClientProtocol // Client connection to plugin
+	Location      string                // Location of the plugin (generally path to binary)
+	Name          string                // Name of the plugin
+	Types         []component.Type      // Component types supported by this plugin
+	Cache         cacher.Cache
+	ParentPlugins []*Plugin
 
 	closers    []func() error
 	components map[component.Type]*Instance
@@ -78,6 +79,31 @@ func (p *Plugin) Close() (err error) {
 	return
 }
 
+func (p *Plugin) SetParentPlugins(typ component.Type) {
+	i := p.components[typ]
+	if i == nil {
+		return
+	}
+	pluginWithParent, ok := i.Component.(PluginWithParent)
+	if !ok {
+		p.logger.Warn("plugin does not support parents",
+			"component", typ.String(),
+			"name", p.Name)
+
+	} else {
+		p.logger.Info("setting plugin parents",
+			"component", typ.String(),
+			"name", p.Name)
+
+		parentComponents := []interface{}{}
+		for _, pp := range p.ParentPlugins {
+			parentComponents = append(parentComponents, pp.components[typ].Component)
+		}
+		// TODO: set parent plugins
+		pluginWithParent.SetParentPlugins(parentComponents)
+	}
+}
+
 // Get specific component type from plugin
 func (p *Plugin) InstanceOf(
 	c component.Type,
@@ -172,3 +198,7 @@ func (p *Plugin) types() []string {
 	}
 	return result
 }
+
+type PluginWithParent interface {
+	SetParentPlugins([]interface{})
+}