Refactor the cli functions to use urfave/cli instead of cobra.

A few variable have been renamed to match, e.g.
cfg.CtrKernelSnapshotter to match defaults.ContainerdKernelSnapshotter

Signed-off-by: Soule BA <soule@weave.works>

cmd/dev-helper/main.go

@@ -79,12 +79,12 @@ func runCreateVMPlanTest(ctx context.Context, nodeNum int, sshKey string, logger
 		},
 		GRPCAPIEndpoint:      "",
 		HTTPAPIEndpoint:      "",
-		CtrSnapshotterKernel: defaults.ContainerdKernelSnapshotter,
-		CtrSnapshotterVolume: defaults.ContainerdVolumeSnapshotter,
+		CtrKernelSnapshotter: defaults.ContainerdKernelSnapshotter,
+		CtrVolumeSnapshotter: defaults.ContainerdVolumeSnapshotter,
 		CtrSocketPath:        socketPath,
 		CtrNamespace:         defaults.ContainerdNamespace,
 		FirecrackerBin:       "/home/richard/bin/firecracker",
-		FirecrackerDetatch:   false,
+		FirecrackerDetach:    false,
 		FirecrackerUseAPI:    true,
 		StateRootDir:         defaults.StateRootDir,
 		ParentIface:          "enp1s0",

cmd/flintlockd/main.go

@@ -1,18 +1,20 @@
 package main
 
 import (
-	"log"
+	"fmt"
+	"io"
+	"os"
 
 	"github.com/weaveworks/flintlock/internal/command"
 )
 
+var out io.Writer = os.Stdout
+
 func main() {
-	rootCmd, err := command.NewRootCommand()
-	if err != nil {
-		log.Fatalln(err)
-	}
+	app := command.NewApp(out)
 
-	if err := rootCmd.Execute(); err != nil {
-		log.Fatalln(err)
+	if err := app.Run(os.Args); err != nil {
+		fmt.Fprintf(os.Stderr, "flintlockd: %s\n", err)
+		os.Exit(1)
 	}
 }

go.mod

@@ -28,10 +28,8 @@ require (
 	github.com/prometheus/client_golang v1.11.0
 	github.com/sirupsen/logrus v1.8.1
 	github.com/spf13/afero v1.6.0
-	github.com/spf13/cobra v1.2.1
-	github.com/spf13/pflag v1.0.5
-	github.com/spf13/viper v1.9.0
 	github.com/stretchr/testify v1.7.0
+	github.com/urfave/cli/v2 v2.3.0
 	github.com/vishvananda/netlink v1.1.1-0.20201029203352-d40f9887b852
 	github.com/weaveworks/flintlock/api v0.0.0-00010101000000-000000000000
 	golang.org/x/net v0.0.0-20210614182718-04defd469f4e // indirect
@@ -41,6 +39,7 @@ require (
 )
 
 require (
+	github.com/BurntSushi/toml v0.3.1 // indirect
 	github.com/Microsoft/hcsshim v0.8.21 // indirect
 	github.com/PuerkitoBio/purell v1.1.1 // indirect
 	github.com/PuerkitoBio/urlesc v0.0.0-20170810143723-de5bf2ad4578 // indirect
@@ -54,6 +53,7 @@ require (
 	github.com/containerd/ttrpc v1.0.2 // indirect
 	github.com/containernetworking/cni v0.8.1 // indirect
 	github.com/containernetworking/plugins v0.9.1 // indirect
+	github.com/cpuguy83/go-md2man/v2 v2.0.0 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/docker/go-events v0.0.0-20190806004212-e31b211e4f1c // indirect
 	github.com/fsnotify/fsnotify v1.5.1 // indirect
@@ -76,11 +76,8 @@ require (
 	github.com/golang/protobuf v1.5.2 // indirect
 	github.com/hashicorp/errwrap v1.0.0 // indirect
 	github.com/hashicorp/go-multierror v1.1.0 // indirect
-	github.com/hashicorp/hcl v1.0.0 // indirect
 	github.com/imdario/mergo v0.3.12 // indirect
-	github.com/inconshreveable/mousetrap v1.0.0 // indirect
 	github.com/leodido/go-urn v1.2.1 // indirect
-	github.com/magiconair/properties v1.8.5 // indirect
 	github.com/mailru/easyjson v0.7.1 // indirect
 	github.com/matttproud/golang_protobuf_extensions v1.0.2-0.20181231171920-c182affec369 // indirect
 	github.com/mitchellh/mapstructure v1.4.2 // indirect
@@ -95,9 +92,8 @@ require (
 	github.com/prometheus/client_model v0.2.0 // indirect
 	github.com/prometheus/common v0.26.0 // indirect
 	github.com/prometheus/procfs v0.6.0 // indirect
-	github.com/spf13/cast v1.4.1 // indirect
-	github.com/spf13/jwalterweatherman v1.1.0 // indirect
-	github.com/subosito/gotenv v1.2.0 // indirect
+	github.com/russross/blackfriday/v2 v2.0.1 // indirect
+	github.com/shurcooL/sanitized_anchor_name v1.0.0 // indirect
 	github.com/vishvananda/netns v0.0.0-20200728191858-db3c7e526aae // indirect
 	go.mongodb.org/mongo-driver v1.7.3 // indirect
 	go.opencensus.io v0.23.0 // indirect
@@ -106,7 +102,6 @@ require (
 	golang.org/x/sys v0.0.0-20210823070655-63515b42dcdf // indirect
 	golang.org/x/text v0.3.6 // indirect
 	google.golang.org/genproto v0.0.0-20211021150943-2b146023228c // indirect
-	gopkg.in/ini.v1 v1.63.2 // indirect
 	gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect
 )

internal/command/flags/flags.go

@@ -1,9 +1,8 @@
 package flags
 
 import (
-	"fmt"
-
-	"github.com/spf13/cobra"
+	"github.com/urfave/cli/v2"
+	"github.com/urfave/cli/v2/altsrc"
 
 	"github.com/weaveworks/flintlock/internal/config"
 	"github.com/weaveworks/flintlock/pkg/defaults"
@@ -26,109 +25,126 @@ const (
 )
 
 // AddGRPCServerFlagsToCommand will add gRPC server flags to the supplied command.
-func AddGRPCServerFlagsToCommand(cmd *cobra.Command, cfg *config.Config) {
-	cmd.Flags().StringVar(&cfg.GRPCAPIEndpoint,
-		grpcEndpointFlag,
-		defaults.GRPCAPIEndpoint,
-		"The endpoint for the gRPC server to listen on.")
+func AddGRPCServerFlagsToCommand(cmd *cli.Command, cfg *config.Config) {
+	cmd.Flags = append(cmd.Flags, altsrc.NewStringFlag(&cli.StringFlag{
+		Name:        grpcEndpointFlag,
+		Usage:       "The endpoint for the gRPC server to listen on.",
+		Value:       defaults.GRPCAPIEndpoint,
+		Destination: &cfg.GRPCAPIEndpoint,
+	}))
 }
 
 // AddGWServerFlagsToCommand will add gRPC HTTP gateway flags to the supplied command.
-func AddGWServerFlagsToCommand(cmd *cobra.Command, cfg *config.Config) {
-	cmd.Flags().StringVar(&cfg.GRPCAPIEndpoint,
-		grpcEndpointFlag,
-		defaults.GRPCAPIEndpoint,
-		"The address of the gRPC server to act as a gateway for.")
-
-	cmd.Flags().StringVar(&cfg.HTTPAPIEndpoint,
-		httpEndpointFlag,
-		defaults.HTTPAPIEndpoint,
-		"The endpoint for the HTTP proxy to the gRPC service to listen on.")
+func AddGWServerFlagsToCommand(cmd *cli.Command, cfg *config.Config) {
+	grpcFlag := altsrc.NewStringFlag(&cli.StringFlag{
+		Name:        grpcEndpointFlag,
+		Usage:       "The address of the gRPC server to act as a gateway for.",
+		Value:       defaults.GRPCAPIEndpoint,
+		Destination: &cfg.GRPCAPIEndpoint,
+	})
+
+	httpFlag := altsrc.NewStringFlag(&cli.StringFlag{
+		Name:        httpEndpointFlag,
+		Usage:       "The endpoint for the HTTP proxy to the gRPC service to listen on.",
+		Value:       defaults.HTTPAPIEndpoint,
+		Destination: &cfg.HTTPAPIEndpoint,
+	})
+
+	cmd.Flags = append(cmd.Flags, grpcFlag, httpFlag)
 }
 
-func AddNetworkFlagsToCommand(cmd *cobra.Command, cfg *config.Config) error {
-	cmd.Flags().StringVar(&cfg.ParentIface,
-		parentIfaceFlag,
-		"",
-		"The parent iface for the network interfaces. Note it could also be a bond")
-
-	if err := cmd.MarkFlagRequired(parentIfaceFlag); err != nil {
-		return fmt.Errorf("setting %s as required: %w", parentIfaceFlag, err)
-	}
-
-	return nil
+func AddNetworkFlagsToCommand(cmd *cli.Command, cfg *config.Config) {
+	cmd.Flags = append(cmd.Flags, altsrc.NewStringFlag(&cli.StringFlag{
+		Name:        parentIfaceFlag,
+		Usage:       "The parent iface for the network interfaces. Note it could also be a bond.",
+		Value:       "",
+		Destination: &cfg.ParentIface,
+	}))
 }
 
-func AddHiddenFlagsToCommand(cmd *cobra.Command, cfg *config.Config) error {
-	cmd.Flags().BoolVar(&cfg.DisableReconcile,
-		disableReconcileFlag,
-		false,
-		"Set to true to stop the reconciler running")
-
-	cmd.Flags().IntVar(&cfg.MaximumRetry,
-		maximumRetryFlag,
-		defaults.MaximumRetry,
-		"Number of times to retry failed reconciliation")
-
-	cmd.Flags().BoolVar(&cfg.DisableAPI,
-		disableAPIFlag,
-		false,
-		"Set to true to stop the api server running")
-
-	if err := cmd.Flags().MarkHidden(disableReconcileFlag); err != nil {
-		return fmt.Errorf("setting %s as hidden: %w", disableReconcileFlag, err)
-	}
-
-	if err := cmd.Flags().MarkHidden(maximumRetryFlag); err != nil {
-		return fmt.Errorf("setting %s as hidden: %w", maximumRetryFlag, err)
-	}
-
-	if err := cmd.Flags().MarkHidden(disableAPIFlag); err != nil {
-		return fmt.Errorf("setting %s as hidden: %w", disableAPIFlag, err)
-	}
-
-	return nil
+func AddHiddenFlagsToCommand(cmd *cli.Command, cfg *config.Config) {
+	disableReconcileFlag := altsrc.NewBoolFlag(&cli.BoolFlag{
+		Name:        disableReconcileFlag,
+		Usage:       "Set to true to disable the reconciler.",
+		Value:       false,
+		Hidden:      true,
+		Destination: &cfg.DisableReconcile,
+	})
+
+	maximumRetryFlag := altsrc.NewIntFlag(&cli.IntFlag{
+		Name:        maximumRetryFlag,
+		Usage:       "The maximum number of times to retry a failed reconciliation.",
+		Value:       defaults.MaximumRetry,
+		Hidden:      true,
+		Destination: &cfg.MaximumRetry,
+	})
+
+	disableAPIFlag := altsrc.NewBoolFlag(&cli.BoolFlag{
+		Name:        disableAPIFlag,
+		Usage:       "Set to true to disable the API server.",
+		Value:       false,
+		Hidden:      true,
+		Destination: &cfg.DisableAPI,
+	})
+
+	cmd.Flags = append(cmd.Flags, disableReconcileFlag, maximumRetryFlag, disableAPIFlag)
 }
 
 // AddFirecrackerFlagsToCommand will add the firecracker provider specific flags to the supplied cobra command.
-func AddFirecrackerFlagsToCommand(cmd *cobra.Command, cfg *config.Config) error {
-	cmd.Flags().StringVar(&cfg.FirecrackerBin,
-		firecrackerBinFlag,
-		defaults.FirecrackerBin,
-		"The path to the firecracker binary to use.")
-	cmd.Flags().BoolVar(&cfg.FirecrackerDetatch,
-		firecrackerDetachFlag,
-		defaults.FirecrackerDetach,
-		"If true the child firecracker processes will be detached from the parent flintlock process.")
-	cmd.Flags().BoolVar(&cfg.FirecrackerUseAPI,
-		firecrackerAPIFlag,
-		defaults.FirecrackerUseAPI,
-		"Indicates that the Firecracker API should be used to configure the microvm.")
-
-	return nil
+func AddFirecrackerFlagsToCommand(cmd *cli.Command, cfg *config.Config) {
+	firecrackerBinFlag := altsrc.NewStringFlag(&cli.StringFlag{
+		Name:        firecrackerBinFlag,
+		Usage:       "The path to the firecracker binary.",
+		Value:       defaults.FirecrackerBin,
+		Destination: &cfg.FirecrackerBin,
+	})
+
+	firecrackerDetachFlag := altsrc.NewBoolFlag(&cli.BoolFlag{
+		Name:        firecrackerDetachFlag,
+		Usage:       "Set to true to detach the firecracker process from the parent process.",
+		Value:       defaults.FirecrackerDetach,
+		Destination: &cfg.FirecrackerDetach,
+	})
+
+	firecrackerAPIFlag := altsrc.NewBoolFlag(&cli.BoolFlag{
+		Name:        firecrackerAPIFlag,
+		Usage:       "Set to true to enable the firecracker API to configure the microvm.",
+		Value:       defaults.FirecrackerUseAPI,
+		Destination: &cfg.FirecrackerUseAPI,
+	})
+
+	cmd.Flags = append(cmd.Flags, firecrackerBinFlag, firecrackerDetachFlag, firecrackerAPIFlag)
 }
 
 // AddContainerDFlagsToCommand will add the containerd specific flags to the supplied cobra command.
-func AddContainerDFlagsToCommand(cmd *cobra.Command, cfg *config.Config) error {
-	cmd.Flags().StringVar(&cfg.CtrSocketPath,
-		containerdSocketFlag,
-		defaults.ContainerdSocket,
-		"The path to the containerd socket.")
-
-	cmd.Flags().StringVar(&cfg.CtrSnapshotterKernel,
-		kernelSnapshotterFlag,
-		defaults.ContainerdKernelSnapshotter,
-		"The name of the snapshotter to use with containerd for kernel/initrd images.")
-
-	cmd.Flags().StringVar(&cfg.CtrSnapshotterVolume,
-		volSnapshotterFlag,
-		defaults.ContainerdVolumeSnapshotter,
-		"The name of the snapshotter to use with containerd for volume images.")
-
-	cmd.Flags().StringVar(&cfg.CtrNamespace,
-		containerdNamespace,
-		defaults.ContainerdNamespace,
-		"The name of the containerd namespace to use.")
-
-	return nil
+func AddContainerDFlagsToCommand(cmd *cli.Command, cfg *config.Config) {
+	containerdSocketFlag := altsrc.NewPathFlag(&cli.PathFlag{
+		Name:        containerdSocketFlag,
+		Usage:       "The path to the containerd socket.",
+		Value:       defaults.ContainerdSocket,
+		Destination: &cfg.CtrSocketPath,
+	})
+
+	volSnapshotterFlag := altsrc.NewStringFlag(&cli.StringFlag{
+		Name:        volSnapshotterFlag,
+		Usage:       "The volume snapshotter to use.",
+		Value:       defaults.ContainerdVolumeSnapshotter,
+		Destination: &cfg.CtrVolumeSnapshotter,
+	})
+
+	kernelSnapshotterFlag := altsrc.NewStringFlag(&cli.StringFlag{
+		Name:        kernelSnapshotterFlag,
+		Usage:       "The kernel snapshotter to use.",
+		Value:       defaults.ContainerdKernelSnapshotter,
+		Destination: &cfg.CtrKernelSnapshotter,
+	})
+
+	containerdNamespaceFlag := altsrc.NewStringFlag(&cli.StringFlag{
+		Name:        containerdNamespace,
+		Usage:       "The containerd namespace to use.",
+		Value:       defaults.ContainerdNamespace,
+		Destination: &cfg.CtrNamespace,
+	})
+
+	cmd.Flags = append(cmd.Flags, containerdSocketFlag, volSnapshotterFlag, kernelSnapshotterFlag, containerdNamespaceFlag)
 }