feat(cli): implement docksight agent status

apps/cli/cmd/agent_status.go

@@ -0,0 +1,78 @@
+package cmd
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/Open-Source-Kigali/docksight/apps/cli/cmd/internal/agent/install"
+	"github.com/Open-Source-Kigali/docksight/apps/cli/cmd/internal/system"
+	"github.com/Open-Source-Kigali/docksight/apps/cli/cmd/internal/ui"
+
+	"github.com/spf13/cobra"
+)
+
+var agentStatusCMD = &cobra.Command{
+	Use:   "status",
+	Short: "Show the agent service status",
+	Long: "Report whether the agent is installed and running, which platform " +
+		"URL it targets, and whether an identity has been issued. Exits non-zero " +
+		"when the agent is not installed or not running.",
+
+	RunE: func(cmd *cobra.Command, args []string) error {
+		layout := agentLayout()
+
+		if _, err := os.Stat(layout.ConfigPath()); err != nil {
+			if os.IsNotExist(err) {
+				return fmt.Errorf(
+					"agent is not installed (no config at %s)",
+					layout.ConfigPath(),
+				)
+			}
+			return err
+		}
+
+		manager := install.NewController(layout)
+		unit := layout.ServiceName
+
+		active, err := manager.IsActive(cmd.Context(), unit)
+		if err != nil {
+			if isPermissionError(err) {
+				return fmt.Errorf(
+					"could not query %s status: %w\n  %s",
+					unit,
+					err,
+					system.ElevationHint(),
+				)
+			}
+			return fmt.Errorf("could not query %s status: %w", unit, err)
+		}
+
+		serverURL, err := install.ReadServerURL(layout)
+		if err != nil {
+			serverURL = "(unavailable: " + err.Error() + ")"
+		}
+
+		identity := "not issued"
+		if install.IdentityExists(layout) {
+			identity = "issued"
+		}
+
+		if active {
+			ui.Success(unit + ": running")
+		} else {
+			ui.Warning(unit + ": not running")
+		}
+		ui.Info("Platform URL: " + serverURL)
+		ui.Info("Identity: " + identity)
+		ui.Info("Follow logs: " + layout.LogsCommand())
+
+		if !active {
+			return fmt.Errorf("%s is not running", unit)
+		}
+		return nil
+	},
+}
+
+func init() {
+	agentCMD.AddCommand(agentStatusCMD)
+}

apps/cli/cmd/agent_stubs.go

@@ -15,27 +15,22 @@ var agentPlaceholders = []struct {
 }{
 	{"uninstall", "Remove the DockSight Agent from this host"},
 	// start / stop / restart are real commands in agent_service.go
-	{"status", "Show the agent service status"},
+	// status is a real command in agent_status.go
 	{"logs", "Show the agent service logs"},
 }
 
 func init() {
-
 	for _, placeholder := range agentPlaceholders {
-
 		command := &cobra.Command{
 			Use:   placeholder.use,
 			Short: placeholder.short,
-
 			RunE: func(cmd *cobra.Command, args []string) error {
-
 				return fmt.Errorf(
 					"docksight agent %s will be ready soon",
 					cmd.Name(),
 				)
 			},
 		}
-
 		agentCMD.AddCommand(command)
 	}
 }