lxc: Add completions for server keys and console (#14115)

Resolves #14098.

All the improvements made to the `lxc config get/set` completions have
been tested locally. I made a minor change that deviates from the
requirements outlined in #14098.
Instead of typing `lxc config get foo:core.<tab>` to retrieve server
configuration options, typing `lxc config get foo: core.<tab>` (notice
the [SPACE]) will now return server configuration options. This change
was implemented to differentiate from the conventional usage of
`remote:instance` across the CLI. However, please let me know if you'd
prefer server configuration completions without the [SPACE] 😄.

client/interfaces.go

@@ -73,6 +73,7 @@ type InstanceServer interface {
 	ImageServer
 
 	// Server functions
+	GetMetadataConfiguration() (metadataConfiguration *api.MetadataConfiguration, err error)
 	GetMetrics() (metrics string, err error)
 	GetServer() (server *api.Server, ETag string, err error)
 	GetServerResources() (resources *api.Resources, err error)

client/lxd_server.go

@@ -186,3 +186,21 @@ func (r *ProtocolLXD) GetMetrics() (string, error) {
 
 	return string(content), nil
 }
+
+// GetMetadataConfiguration returns metadata configuration for a server.
+func (r *ProtocolLXD) GetMetadataConfiguration() (*api.MetadataConfiguration, error) {
+	// Check that the server supports it.
+	err := r.CheckExtension("metadata_configuration")
+	if err != nil {
+		return nil, err
+	}
+
+	metadataConfiguration := api.MetadataConfiguration{}
+
+	_, err = r.queryStruct(http.MethodGet, api.NewURL().Path("metadata", "configuration").String(), nil, "", &metadataConfiguration)
+	if err != nil {
+		return nil, err
+	}
+
+	return &metadataConfiguration, err
+}

lxc/completion.go

@@ -211,6 +211,18 @@ func (g *cmdGlobal) cmpImages(toComplete string) ([]string, cobra.ShellCompDirec
 }
 
 func (g *cmdGlobal) cmpInstanceAllKeys(instanceName string) ([]string, cobra.ShellCompDirective) {
+	var keys []string
+	cmpDirectives := cobra.ShellCompDirectiveNoFileComp
+
+	_, instanceNameOnly, _ := strings.Cut(instanceName, ":")
+	if instanceNameOnly == "" {
+		serverKeys, directives := g.cmpServerAllKeys(instanceName)
+		keys = append(keys, serverKeys...)
+		cmpDirectives = directives
+
+		return keys, cmpDirectives
+	}
+
 	resources, err := g.ParseServers(instanceName)
 	if err != nil || len(resources) == 0 {
 		return nil, cobra.ShellCompDirectiveError
@@ -219,13 +231,12 @@ func (g *cmdGlobal) cmpInstanceAllKeys(instanceName string) ([]string, cobra.She
 	resource := resources[0]
 	client := resource.server
 
-	instanceNameOnly, _, err := client.GetInstance(instanceName)
+	instance, _, err := client.GetInstance(instanceNameOnly)
 	if err != nil {
 		return nil, cobra.ShellCompDirectiveError
 	}
 
-	var keys []string
-	instanceType := instanceNameOnly.Type
+	instanceType := instance.Type
 
 	if instanceType == "container" {
 		for k := range instancetype.InstanceConfigKeysContainer {
@@ -241,6 +252,43 @@ func (g *cmdGlobal) cmpInstanceAllKeys(instanceName string) ([]string, cobra.She
 		keys = append(keys, k)
 	}
 
+	return keys, cmpDirectives
+}
+
+func (g *cmdGlobal) cmpServerAllKeys(instanceName string) ([]string, cobra.ShellCompDirective) {
+	resources, err := g.ParseServers(instanceName)
+	if err != nil || len(resources) == 0 {
+		return nil, cobra.ShellCompDirectiveError
+	}
+
+	resource := resources[0]
+	client := resource.server
+
+	metadataConfiguration, err := client.GetMetadataConfiguration()
+	if err != nil {
+		return nil, cobra.ShellCompDirectiveError
+	}
+
+	server, ok := metadataConfiguration.Configs["server"]
+	if !ok {
+		return nil, cobra.ShellCompDirectiveError
+	}
+
+	keyCount := 0
+	for _, field := range server {
+		keyCount += len(field.Keys)
+	}
+
+	keys := make([]string, 0, keyCount)
+
+	for _, field := range server {
+		for _, keyMap := range field.Keys {
+			for key := range keyMap {
+				keys = append(keys, key)
+			}
+		}
+	}
+
 	return keys, cobra.ShellCompDirectiveNoFileComp
 }
 
@@ -937,6 +985,10 @@ func (g *cmdGlobal) cmpRemotes(includeAll bool) ([]string, cobra.ShellCompDirect
 			continue
 		}
 
+		if remoteName == "local" || rc.Protocol == "simplestreams" {
+			continue
+		}
+
 		results = append(results, fmt.Sprintf("%s:", remoteName))
 	}
 

lxc/config.go

@@ -400,6 +400,10 @@ func (c *cmdConfigGet) command() *cobra.Command {
 
 	cmd.ValidArgsFunction = func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
 		if len(args) == 0 {
+			if strings.Contains(toComplete, ".") {
+				return c.global.cmpServerAllKeys(toComplete)
+			}
+
 			return c.global.cmpInstances(toComplete)
 		}
 
@@ -553,6 +557,10 @@ lxc config set core.https_address=[::]:8443
 
 	cmd.ValidArgsFunction = func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
 		if len(args) == 0 {
+			if strings.Contains(toComplete, ".") {
+				return c.global.cmpServerAllKeys(toComplete)
+			}
+
 			return c.global.cmpInstances(toComplete)
 		}
 
@@ -902,6 +910,10 @@ func (c *cmdConfigUnset) command() *cobra.Command {
 
 	cmd.ValidArgsFunction = func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
 		if len(args) == 0 {
+			if strings.Contains(toComplete, ".") {
+				return c.global.cmpServerAllKeys(toComplete)
+			}
+
 			return c.global.cmpInstances(toComplete)
 		}
 

lxc/console.go

@@ -44,6 +44,10 @@ as well as retrieve past log entries from it.`))
 	cmd.Flags().BoolVar(&c.flagShowLog, "show-log", false, i18n.G("Retrieve the container's console log"))
 	cmd.Flags().StringVarP(&c.flagType, "type", "t", "console", i18n.G("Type of connection to establish: 'console' for serial console, 'vga' for SPICE graphical output")+"``")
 
+	cmd.ValidArgsFunction = func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
+		return c.global.cmpInstances(toComplete)
+	}
+
 	return cmd
 }