fix(config): enable multiple inheritance for bee-config, node-group, …

…and cluster (#412)

pkg/config/bee.go

@@ -7,6 +7,10 @@ import (
 	"github.com/ethersphere/beekeeper/pkg/orchestration"
 )
 
+type Inheritable interface {
+	GetParentName() string
+}
+
 // BeeConfig represents Bee configuration
 type BeeConfig struct {
 	// parent to inherit settings from
@@ -56,6 +60,13 @@ type BeeConfig struct {
 	WithdrawAddress           *string        `yaml:"withdrawal-addresses-whitelist"`
 }
 
+func (b BeeConfig) GetParentName() string {
+	if b.Inherit != nil {
+		return b.Inherit.ParentName
+	}
+	return ""
+}
+
 // Export exports BeeConfig to orchestration.Config
 func (b *BeeConfig) Export() (o orchestration.Config) {
 	localVal := reflect.ValueOf(b).Elem()

pkg/config/cluster.go

@@ -22,6 +22,13 @@ type Cluster struct {
 	NodeGroups         *map[string]ClusterNodeGroup `yaml:"node-groups"`
 }
 
+func (b Cluster) GetParentName() string {
+	if b.Inherit != nil {
+		return b.Inherit.ParentName
+	}
+	return ""
+}
+
 // ClusterNodeGroup represents node group in the cluster
 type ClusterNodeGroup struct {
 	cluster       *Cluster

pkg/config/config.go

@@ -32,82 +32,90 @@ func (c *Config) PrintYaml(w io.Writer) (err error) {
 	if c == nil {
 		return fmt.Errorf("config not initialized")
 	}
-	enc := yaml.NewEncoder(w)
-	if err := enc.Encode(c); err != nil {
+	if err := yaml.NewEncoder(w).Encode(c); err != nil {
 		return fmt.Errorf("config can not be encoded: %s", err.Error())
 	}
 	return
 }
 
 // merge combines Config objects using inheritance
 func (c *Config) merge() (err error) {
-	// merge BeeConfigs
-	mergedBC := map[string]BeeConfig{}
-	for name, v := range c.BeeConfigs {
-		if len(v.ParentName) == 0 {
-			mergedBC[name] = v
-		} else {
-			parent, ok := c.BeeConfigs[v.ParentName]
-			if !ok {
-				return fmt.Errorf("bee profile %s doesn't exist", v.ParentName)
-			}
-			p := reflect.ValueOf(&parent).Elem()
-			m := reflect.ValueOf(&v).Elem()
-			for i := 0; i < m.NumField(); i++ {
-				if m.Field(i).IsNil() && !p.Field(i).IsNil() {
-					m.Field(i).Set(p.Field(i))
-				}
-			}
-			mergedBC[name] = m.Interface().(BeeConfig)
-		}
+	c.BeeConfigs, err = mergeConfigs(c.BeeConfigs)
+	if err != nil {
+		return fmt.Errorf("merging bee configs: %w", err)
 	}
-	c.BeeConfigs = mergedBC
-
-	// merge NodeGroups
-	mergedNG := map[string]NodeGroup{}
-	for name, v := range c.NodeGroups {
-		if len(v.ParentName) == 0 {
-			mergedNG[name] = v
-		} else {
-			parent, ok := c.NodeGroups[v.ParentName]
-			if !ok {
-				return fmt.Errorf("node group profile %s doesn't exist", v.ParentName)
+
+	c.NodeGroups, err = mergeConfigs(c.NodeGroups)
+	if err != nil {
+		return fmt.Errorf("merging node groups: %w", err)
+	}
+
+	c.Clusters, err = mergeConfigs(c.Clusters)
+	if err != nil {
+		return fmt.Errorf("merging clusters: %w", err)
+	}
+
+	return
+}
+
+func mergeConfigs[T any](configs map[string]T) (map[string]T, error) {
+	mergedConfigs := make(map[string]T)
+	visited := map[string]bool{}
+
+	// recursively merge configs (internal function)
+	var mergeParent func(name string) (T, error)
+	mergeParent = func(name string) (T, error) {
+		if config, ok := mergedConfigs[name]; ok {
+			return config, nil // already merged
+		}
+		var zero T
+
+		// detect circular inheritance
+		if visited[name] {
+			return zero, fmt.Errorf("circular inheritance detected with bee profile %s", name)
+		}
+		visited[name] = true
+
+		v, ok := configs[name]
+		if !ok {
+			return zero, fmt.Errorf("bee profile %s doesn't exist", name)
+		}
+
+		// check if T implements Inheritable to get parent name
+		vIneheritable, ok := any(v).(Inheritable)
+		if !ok {
+			return zero, fmt.Errorf("type %T does not implement Inheritable interface", v)
+		}
+
+		// merge the parent
+		if len(vIneheritable.GetParentName()) > 0 {
+			parentConfig, err := mergeParent(vIneheritable.GetParentName())
+			if err != nil {
+				return zero, err
 			}
-			p := reflect.ValueOf(&parent).Elem()
+
+			// merge parent fields into the current config
+			p := reflect.ValueOf(&parentConfig).Elem()
 			m := reflect.ValueOf(&v).Elem()
 			for i := 0; i < m.NumField(); i++ {
 				if m.Field(i).IsNil() && !p.Field(i).IsNil() {
 					m.Field(i).Set(p.Field(i))
 				}
 			}
-			mergedNG[name] = m.Interface().(NodeGroup)
 		}
+
+		mergedConfigs[name] = v
+		delete(visited, name) // remove after merge
+		return v, nil
 	}
-	c.NodeGroups = mergedNG
-
-	// merge clusters
-	mergedC := map[string]Cluster{}
-	for name, v := range c.Clusters {
-		if len(v.ParentName) == 0 {
-			mergedC[name] = v
-		} else {
-			parent, ok := c.Clusters[v.ParentName]
-			if !ok {
-				return fmt.Errorf("bee profile %s doesn't exist", v.ParentName)
-			}
-			p := reflect.ValueOf(&parent).Elem()
-			m := reflect.ValueOf(&v).Elem()
-			for i := 0; i < m.NumField(); i++ {
-				if m.Field(i).IsNil() && !p.Field(i).IsNil() {
-					m.Field(i).Set(p.Field(i))
-				}
-			}
-			mergedC[name] = m.Interface().(Cluster)
+
+	for name := range configs {
+		if _, err := mergeParent(name); err != nil {
+			return nil, err
 		}
 	}
-	c.Clusters = mergedC
 
-	return
+	return mergedConfigs, nil
 }
 
 // Read reads given YAML files and unmarshals them into Config

pkg/config/nodegroup.go

@@ -31,6 +31,13 @@ type NodeGroup struct {
 	UpdateStrategy            *string            `yaml:"update-strategy"`
 }
 
+func (b NodeGroup) GetParentName() string {
+	if b.Inherit != nil {
+		return b.Inherit.ParentName
+	}
+	return ""
+}
+
 // Export exports NodeGroup to orchestration.NodeGroupOptions
 func (n *NodeGroup) Export() (o orchestration.NodeGroupOptions) {
 	localVal := reflect.ValueOf(n).Elem()