cli: add system command and subcmds to interact with system API.

The system command includes gc and reconcile-summaries subcommands
which covers all currently available system API calls. The help
information is largely pulled from the current Nomad website API
documentation.

command/commands.go

@@ -610,6 +610,26 @@ func Commands(metaPtr *Meta, agentUi cli.Ui) map[string]cli.CommandFactory {
 				Meta: meta,
 			}, nil
 		},
+		"system": func() (cli.Command, error) {
+			return &SystemCommand{
+				Meta: meta,
+			}, nil
+		},
+		"system gc": func() (cli.Command, error) {
+			return &SystemGCCommand{
+				Meta: meta,
+			}, nil
+		},
+		"system reconcile": func() (cli.Command, error) {
+			return &SystemReconcileCommand{
+				Meta: meta,
+			}, nil
+		},
+		"system reconcile summaries": func() (cli.Command, error) {
+			return &SystemReconcileSummariesCommand{
+				Meta: meta,
+			}, nil
+		},
 		"ui": func() (cli.Command, error) {
 			return &UiCommand{
 				Meta: meta,

command/system.go

@@ -0,0 +1,35 @@
+package command
+
+import (
+	"strings"
+
+	"github.com/mitchellh/cli"
+)
+
+type SystemCommand struct {
+	Meta
+}
+
+func (sc *SystemCommand) Help() string {
+	helpText := `
+Usage: nomad system <subcommand> [options]
+
+  This command groups subcommands for interacting with the system API. Users
+  can perform system maintenance tasks such as trigger the garbage collector or
+  perform job summary reconciliation.
+
+  Please see the individual subcommand help for detailed usage information.
+`
+
+	return strings.TrimSpace(helpText)
+}
+
+func (sc *SystemCommand) Synopsis() string {
+	return "Interact with the system API"
+}
+
+func (sc *SystemCommand) Name() string { return "system" }
+
+func (sc *SystemCommand) Run(args []string) int {
+	return cli.RunResultHelp
+}

command/system_gc.go

@@ -0,0 +1,54 @@
+package command
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/posener/complete"
+)
+
+type SystemGCCommand struct {
+	Meta
+}
+
+func (c *SystemGCCommand) Help() string {
+	helpText := `
+Usage: nomad system gc [options]
+
+  Initializes a garbage collection of jobs, evaluations, allocations, and nodes.
+
+General Options:
+
+  ` + generalOptionsUsage()
+	return strings.TrimSpace(helpText)
+}
+
+func (c *SystemGCCommand) Synopsis() string {
+	return "Run the system garbage collection process"
+}
+
+func (c *SystemGCCommand) AutocompleteFlags() complete.Flags {
+	return c.Meta.AutocompleteFlags(FlagSetClient)
+}
+
+func (c *SystemGCCommand) AutocompleteArgs() complete.Predictor {
+	return complete.PredictNothing
+}
+
+func (c *SystemGCCommand) Name() string { return "system gc" }
+
+func (c *SystemGCCommand) Run(args []string) int {
+
+	// Get the HTTP client
+	client, err := c.Meta.Client()
+	if err != nil {
+		c.Ui.Error(fmt.Sprintf("Error initializing client: %s", err))
+		return 1
+	}
+
+	if err := client.System().GarbageCollect(); err != nil {
+		c.Ui.Error(fmt.Sprintf("Error running system garbage-collection: %s", err))
+		return 1
+	}
+	return 0
+}

command/system_gc_test.go

@@ -0,0 +1,27 @@
+package command
+
+import (
+	"testing"
+
+	"github.com/mitchellh/cli"
+)
+
+func TestSystemGCCommand_Implements(t *testing.T) {
+	t.Parallel()
+	var _ cli.Command = &SystemGCCommand{}
+}
+
+func TestSystemGCCommand_Good(t *testing.T) {
+	t.Parallel()
+
+	// Create a server
+	srv, _, url := testServer(t, true, nil)
+	defer srv.Shutdown()
+
+	ui := new(cli.MockUi)
+	cmd := &SystemGCCommand{Meta: Meta{Ui: ui, flagAddress: url}}
+
+	if code := cmd.Run([]string{"-address=" + url}); code != 0 {
+		t.Fatalf("expected exit 0, got: %d; %v", code, ui.ErrorWriter.String())
+	}
+}

command/system_reconcile.go

@@ -0,0 +1,37 @@
+package command
+
+import (
+	"strings"
+
+	"github.com/mitchellh/cli"
+)
+
+type SystemReconcileCommand struct {
+	Meta
+}
+
+func (s *SystemReconcileCommand) Help() string {
+	helpText := `
+Usage: nomad system reconcile <subcommand> [options]
+
+  This command groups subcommands for interacting with the system reconcile API.
+
+  Reconcile the summaries of all registered jobs:
+
+      $ nomad system reconcile summaries
+
+  Please see the individual subcommand help for detailed usage information.
+`
+
+	return strings.TrimSpace(helpText)
+}
+
+func (s *SystemReconcileCommand) Synopsis() string {
+	return "Perform system reconciliation tasks"
+}
+
+func (s *SystemReconcileCommand) Name() string { return "system reconcile" }
+
+func (s *SystemReconcileCommand) Run(args []string) int {
+	return cli.RunResultHelp
+}

command/system_reconcile_summaries.go

@@ -0,0 +1,54 @@
+package command
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/posener/complete"
+)
+
+type SystemReconcileSummariesCommand struct {
+	Meta
+}
+
+func (c *SystemReconcileSummariesCommand) Help() string {
+	helpText := `
+Usage: nomad system reconcile summaries [options]
+
+  Reconciles the summaries of all registered jobs.
+
+General Options:
+
+  ` + generalOptionsUsage()
+	return strings.TrimSpace(helpText)
+}
+
+func (c *SystemReconcileSummariesCommand) Synopsis() string {
+	return "Reconciles the summaries of all registered jobs"
+}
+
+func (c *SystemReconcileSummariesCommand) AutocompleteFlags() complete.Flags {
+	return c.Meta.AutocompleteFlags(FlagSetClient)
+}
+
+func (c *SystemReconcileSummariesCommand) AutocompleteArgs() complete.Predictor {
+	return complete.PredictNothing
+}
+
+func (c *SystemReconcileSummariesCommand) Name() string { return "system reconcile summaries" }
+
+func (c *SystemReconcileSummariesCommand) Run(args []string) int {
+
+	// Get the HTTP client
+	client, err := c.Meta.Client()
+	if err != nil {
+		c.Ui.Error(fmt.Sprintf("Error initializing client: %s", err))
+		return 1
+	}
+
+	if err := client.System().ReconcileSummaries(); err != nil {
+		c.Ui.Error(fmt.Sprintf("Error running system summary reconciliation: %s", err))
+		return 1
+	}
+	return 0
+}

command/system_reconcile_summaries_test.go

@@ -0,0 +1,27 @@
+package command
+
+import (
+	"testing"
+
+	"github.com/mitchellh/cli"
+)
+
+func TestSystemReconcileSummariesCommand_Implements(t *testing.T) {
+	t.Parallel()
+	var _ cli.Command = &SystemReconcileSummariesCommand{}
+}
+
+func TestSystemReconcileSummariesCommand_Good(t *testing.T) {
+	t.Parallel()
+
+	// Create a server
+	srv, _, url := testServer(t, true, nil)
+	defer srv.Shutdown()
+
+	ui := new(cli.MockUi)
+	cmd := &SystemReconcileSummariesCommand{Meta: Meta{Ui: ui, flagAddress: url}}
+
+	if code := cmd.Run([]string{"-address=" + url}); code != 0 {
+		t.Fatalf("expected exit 0, got: %d; %v", code, ui.ErrorWriter.String())
+	}
+}

command/system_reconcile_test.go

@@ -0,0 +1,12 @@
+package command
+
+import (
+	"testing"
+
+	"github.com/mitchellh/cli"
+)
+
+func TestSystemReconcileCommand_Implements(t *testing.T) {
+	t.Parallel()
+	var _ cli.Command = &SystemCommand{}
+}

command/system_test.go

@@ -0,0 +1,12 @@
+package command
+
+import (
+	"testing"
+
+	"github.com/mitchellh/cli"
+)
+
+func TestSystemCommand_Implements(t *testing.T) {
+	t.Parallel()
+	var _ cli.Command = &SystemCommand{}
+}