Refactor instance node handling to use a map

pkg/instance/instance.go

@@ -193,8 +193,10 @@ func (i *Instance) GetProxy() (*httputil.ReverseProxy, error) {
 
 	// Remote instances should not use local proxy - they are handled by RemoteInstanceProxy
 	opts := i.GetOptions()
-	if opts != nil && len(opts.Nodes) > 0 && opts.Nodes[0] != i.localNodeName {
+	if opts != nil && len(opts.Nodes) > 0 {
-		return nil, fmt.Errorf("instance %s is a remote instance and should not use local proxy", i.Name)
+		if _, isLocal := opts.Nodes[i.localNodeName]; !isLocal {
+			return nil, fmt.Errorf("instance %s is a remote instance and should not use local proxy", i.Name)
+		}
 	}
 
 	return i.proxy.GetProxy()
@@ -303,8 +305,8 @@ func (i *Instance) IsRemote() bool {
 		return false
 	}
 
-	// If the first node is the local node, treat it as a local instance
+	// If the local node is in the nodes map, treat it as a local instance
-	if opts.Nodes[0] == i.localNodeName {
+	if _, isLocal := opts.Nodes[i.localNodeName]; isLocal {
 		return false
 	}
 

pkg/instance/instance_test.go

@@ -209,7 +209,7 @@ func TestSetOptions_PreservesNodes(t *testing.T) {
 	// Create instance with initial nodes
 	initialOptions := &instance.Options{
 		BackendType: backends.BackendTypeLlamaCpp,
-		Nodes:       []string{"worker1"},
+		Nodes:       map[string]struct{}{"worker1": {}},
 		LlamaServerOptions: &llamacpp.LlamaServerOptions{
 			Model: "/path/to/model.gguf",
 			Port:  8080,
@@ -222,7 +222,7 @@ func TestSetOptions_PreservesNodes(t *testing.T) {
 	// Try to update with different nodes
 	updatedOptions := &instance.Options{
 		BackendType: backends.BackendTypeLlamaCpp,
-		Nodes:       []string{"worker2"}, // Attempt to change node
+		Nodes:       map[string]struct{}{"worker2": {}}, // Attempt to change node
 		LlamaServerOptions: &llamacpp.LlamaServerOptions{
 			Model: "/path/to/new-model.gguf",
 			Port:  8081,
@@ -233,8 +233,8 @@ func TestSetOptions_PreservesNodes(t *testing.T) {
 	opts := inst.GetOptions()
 
 	// Nodes should remain unchanged
-	if len(opts.Nodes) != 1 || opts.Nodes[0] != "worker1" {
+	if _, exists := opts.Nodes["worker1"]; len(opts.Nodes) != 1 || !exists {
-		t.Errorf("Expected nodes to remain ['worker1'], got %v", opts.Nodes)
+		t.Errorf("Expected nodes to contain 'worker1', got %v", opts.Nodes)
 	}
 
 	// Other options should be updated

pkg/instance/options.go

@@ -10,6 +10,7 @@ import (
 	"llamactl/pkg/config"
 	"log"
 	"maps"
+	"slices"
 	"sync"
 )
 
@@ -29,7 +30,7 @@ type Options struct {
 	BackendType    backends.BackendType `json:"backend_type"`
 	BackendOptions map[string]any       `json:"backend_options,omitempty"`
 
-	Nodes []string `json:"nodes,omitempty"`
+	Nodes map[string]struct{} `json:"-"`
 
 	// Backend-specific options
 	LlamaServerOptions *llamacpp.LlamaServerOptions `json:"-"`
@@ -87,6 +88,7 @@ func (c *Options) UnmarshalJSON(data []byte) error {
 	// Use anonymous struct to avoid recursion
 	type Alias Options
 	aux := &struct {
+		Nodes []string `json:"nodes,omitempty"` // Accept JSON array
 		*Alias
 	}{
 		Alias: (*Alias)(c),
@@ -96,6 +98,14 @@ func (c *Options) UnmarshalJSON(data []byte) error {
 		return err
 	}
 
+	// Convert nodes array to map
+	if len(aux.Nodes) > 0 {
+		c.Nodes = make(map[string]struct{}, len(aux.Nodes))
+		for _, node := range aux.Nodes {
+			c.Nodes[node] = struct{}{}
+		}
+	}
+
 	// Parse backend-specific options
 	switch c.BackendType {
 	case backends.BackendTypeLlamaCpp:
@@ -147,11 +157,22 @@ func (c *Options) MarshalJSON() ([]byte, error) {
 	// Use anonymous struct to avoid recursion
 	type Alias Options
 	aux := struct {
+		Nodes []string `json:"nodes,omitempty"` // Output as JSON array
 		*Alias
 	}{
 		Alias: (*Alias)(c),
 	}
 
+	// Convert nodes map to array (sorted for consistency)
+	if len(c.Nodes) > 0 {
+		aux.Nodes = make([]string, 0, len(c.Nodes))
+		for node := range c.Nodes {
+			aux.Nodes = append(aux.Nodes, node)
+		}
+		// Sort for consistent output
+		slices.Sort(aux.Nodes)
+	}
+
 	// Convert backend-specific options back to BackendOptions map for JSON
 	switch c.BackendType {
 	case backends.BackendTypeLlamaCpp:

pkg/manager/manager.go

@@ -275,9 +275,19 @@ func (im *instanceManager) loadInstance(name, path string) error {
 
 	options := persistedInstance.GetOptions()
 
-	// Check if this is a remote instance
+	// Check if this is a remote instance (local node not in the Nodes set)
-	// An instance is remote if Nodes is specified AND the first node is not the local node
+	var isRemote bool
-	isRemote := options != nil && len(options.Nodes) > 0 && options.Nodes[0] != im.localNodeName
+	var nodeName string
+	if options != nil {
+		if _, isLocal := options.Nodes[im.localNodeName]; !isLocal {
+			// Get the first node from the set
+			for node := range options.Nodes {
+				nodeName = node
+				isRemote = true
+				break
+			}
+		}
+	}
 
 	var statusCallback func(oldStatus, newStatus instance.Status)
 	if !isRemote {
@@ -296,7 +306,6 @@ func (im *instanceManager) loadInstance(name, path string) error {
 
 	// Handle remote instance mapping
 	if isRemote {
-		nodeName := options.Nodes[0]
 		nodeConfig, exists := im.nodeConfigMap[nodeName]
 		if !exists {
 			return fmt.Errorf("node %s not found for remote instance %s", nodeName, name)

pkg/manager/operations.go

@@ -3,7 +3,6 @@ package manager
 import (
 	"fmt"
 	"llamactl/pkg/backends"
-	"llamactl/pkg/config"
 	"llamactl/pkg/instance"
 	"llamactl/pkg/validation"
 	"os"
@@ -27,10 +26,12 @@ func (im *instanceManager) updateLocalInstanceFromRemote(localInst *instance.Ins
 
 	// Preserve the Nodes field from the local instance
 	localOptions := localInst.GetOptions()
-	var preservedNodes []string
+	var preservedNodes map[string]struct{}
 	if localOptions != nil && len(localOptions.Nodes) > 0 {
-		preservedNodes = make([]string, len(localOptions.Nodes))
+		preservedNodes = make(map[string]struct{}, len(localOptions.Nodes))
-		copy(preservedNodes, localOptions.Nodes)
+		for node := range localOptions.Nodes {
+			preservedNodes[node] = struct{}{}
+		}
 	}
 
 	// Create a copy of remote options and restore the Nodes field
@@ -98,16 +99,17 @@ func (im *instanceManager) CreateInstance(name string, options *instance.Options
 		return nil, fmt.Errorf("instance with name %s already exists", name)
 	}
 
-	// Check if this is a remote instance
+	// Check if this is a remote instance (local node not in the Nodes set)
-	// An instance is remote if Nodes is specified AND the first node is not the local node
+	if _, isLocal := options.Nodes[im.localNodeName]; !isLocal && len(options.Nodes) > 0 {
-	isRemote := len(options.Nodes) > 0 && options.Nodes[0] != im.localNodeName
+		// Get the first node from the set
-	var nodeConfig *config.NodeConfig
+		var nodeName string
+		for node := range options.Nodes {
+			nodeName = node
+			break
+		}
 
-	if isRemote {
 		// Validate that the node exists
-		nodeName := options.Nodes[0] // Use first node for now
+		nodeConfig, exists := im.nodeConfigMap[nodeName]
-		var exists bool
-		nodeConfig, exists = im.nodeConfigMap[nodeName]
 		if !exists {
 			return nil, fmt.Errorf("node %s not found", nodeName)
 		}

pkg/server/handlers_instances.go

@@ -394,12 +394,21 @@ func (h *Handler) ProxyToInstance() http.HandlerFunc {
 func (h *Handler) RemoteInstanceProxy(w http.ResponseWriter, r *http.Request, name string, inst *instance.Instance) {
 	// Get the node name from instance options
 	options := inst.GetOptions()
-	if options == nil || len(options.Nodes) == 0 {
+	if options == nil {
-		http.Error(w, "Instance has no node configured", http.StatusInternalServerError)
+		http.Error(w, "Instance has no options configured", http.StatusInternalServerError)
 		return
 	}
 
-	nodeName := options.Nodes[0]
+	// Get the first node from the set
+	var nodeName string
+	for node := range options.Nodes {
+		nodeName = node
+		break
+	}
+	if nodeName == "" {
+		http.Error(w, "Instance has no node configured", http.StatusInternalServerError)
+		return
+	}
 
 	// Check if we have a cached proxy for this node
 	h.remoteProxiesMu.RLock()

pkg/server/handlers_openai.go

@@ -155,12 +155,21 @@ func (h *Handler) OpenAIProxy() http.HandlerFunc {
 func (h *Handler) RemoteOpenAIProxy(w http.ResponseWriter, r *http.Request, modelName string, inst *instance.Instance) {
 	// Get the node name from instance options
 	options := inst.GetOptions()
-	if options == nil || len(options.Nodes) == 0 {
+	if options == nil {
-		http.Error(w, "Instance has no node configured", http.StatusInternalServerError)
+		http.Error(w, "Instance has no options configured", http.StatusInternalServerError)
 		return
 	}
 
-	nodeName := options.Nodes[0]
+	// Get the first node from the set
+	var nodeName string
+	for node := range options.Nodes {
+		nodeName = node
+		break
+	}
+	if nodeName == "" {
+		http.Error(w, "Instance has no node configured", http.StatusInternalServerError)
+		return
+	}
 
 	// Check if we have a cached proxy for this node
 	h.remoteProxiesMu.RLock()