add operator describe command (#19)

Author: komish

internal/cmd/operator_describe.go

@@ -0,0 +1,162 @@
+package cmd
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/spf13/cobra"
+
+	operatorsv1 "github.com/operator-framework/operator-lifecycle-manager/pkg/package-server/apis/operators/v1"
+
+	"github.com/operator-framework/kubectl-operator/internal/cmd/internal/log"
+	"github.com/operator-framework/kubectl-operator/internal/pkg/action"
+)
+
+var (
+	// output helpers for the describe subcommand
+	pkgHdr  = asHeader("Package")
+	repoHdr = asHeader("Repository")
+	catHdr  = asHeader("Catalog")
+	chHdr   = asHeader("Channels")
+	imHdr   = asHeader("Install Modes")
+	sdHdr   = asHeader("Description")
+	ldHdr   = asHeader("Long Description")
+
+	repoAnnot = "repository"
+	descAnnot = "description"
+)
+
+func newOperatorDescribeCmd(cfg *action.Configuration) *cobra.Command {
+	l := action.NewOperatorListAvailable(cfg)
+	// receivers for cmdline flags
+	var channel string
+	var longDescription bool
+
+	cmd := &cobra.Command{
+		Use:   "describe <operator>",
+		Short: "Describe an operator",
+		Args:  cobra.ExactArgs(1),
+		Run: func(cmd *cobra.Command, args []string) {
+			// the operator to show details about, provided by the user
+			l.Package = args[0]
+
+			// Find the package manifest and package channel for the operator
+			pms, err := l.Run(cmd.Context())
+			if err != nil {
+				log.Fatalf("failed to find operator: %v", err)
+			}
+
+			// we only expect one item because describe always searches
+			// for a specific operator by name
+			pm := &pms[0]
+
+			// If the user asked for a channel, look for that
+			if channel == "" {
+				channel = pm.Status.DefaultChannel
+			}
+
+			pc, err := getPackageChannel(channel, pm)
+			if err != nil {
+				// the requested channel doesn't exist
+				log.Fatalf("failed to find channel for operator: %v", err)
+			}
+
+			// prepare what we want to print to the console
+			out := make([]string, 0)
+
+			// Starting adding data to our output.
+			out = append(out,
+				// package
+				pkgHdr+fmt.Sprintf("%s %s (by %s)\n\n",
+					pc.CurrentCSVDesc.DisplayName,
+					pc.CurrentCSVDesc.Version,
+					pc.CurrentCSVDesc.Provider.Name),
+				// repo
+				repoHdr+fmt.Sprintf("%s\n\n",
+					pc.CurrentCSVDesc.Annotations[repoAnnot]),
+				// catalog
+				catHdr+fmt.Sprintf("%s\n\n", pm.Status.CatalogSourceDisplayName),
+				// available channels
+				chHdr+fmt.Sprintf("%s\n\n",
+					strings.Join(getAvailableChannelsWithMarkers(channel, pm), "\n")),
+				// install modes
+				imHdr+fmt.Sprintf("%s\n\n",
+					strings.Join(getSupportedInstallModes(pc), "\n")),
+				// description
+				sdHdr+fmt.Sprintf("%s\n",
+					pc.CurrentCSVDesc.Annotations[descAnnot]),
+			)
+
+			// if the user requested a long description, add it to the output as well
+			if longDescription {
+				out = append(out,
+					"\n"+ldHdr+pm.Status.Channels[0].CurrentCSVDesc.LongDescription)
+			}
+
+			// finally, print operator information to the console
+			for _, v := range out {
+				fmt.Print(v)
+			}
+
+		},
+	}
+
+	// add flags to the flagset for this command.
+	cmd.Flags().StringVarP(&channel, "channel", "c", "", "channel")
+	cmd.Flags().BoolVarP(&longDescription, "with-long-description", "L", false, "long description")
+
+	return cmd
+}
+
+// asHeader returns the string with "header bars" for displaying in
+// plain text cases.
+func asHeader(s string) string {
+	return fmt.Sprintf("== %s ==\n", s)
+}
+
+// getPackageChannel returns the package channel specified, or the default if none was specified.
+func getPackageChannel(channel string, pm *operatorsv1.PackageManifest) (*operatorsv1.PackageChannel, error) {
+	var packageChannel *operatorsv1.PackageChannel
+	for _, ch := range pm.Status.Channels {
+		ch := ch
+		if ch.Name == channel {
+			packageChannel = &ch
+		}
+	}
+	if packageChannel == nil {
+		return nil, fmt.Errorf("channel %q does not exist for package %q", channel, pm.GetName())
+	}
+	return packageChannel, nil
+}
+
+// GetSupportedInstallModes returns a string slice representation of install mode
+// objects the operator supports.
+func getSupportedInstallModes(pc *operatorsv1.PackageChannel) []string {
+	supportedInstallModes := make([]string, 1)
+	for _, imode := range pc.CurrentCSVDesc.InstallModes {
+		if imode.Supported {
+			supportedInstallModes = append(supportedInstallModes, string(imode.Type))
+		}
+	}
+
+	return supportedInstallModes
+}
+
+// getAvailableChannelsWithMarkers parses all available package channels for a package manifest
+// and returns those channel names with indicators for pretty-printing whether they are shown
+// or the default channel
+func getAvailableChannelsWithMarkers(channel string, pm *operatorsv1.PackageManifest) []string {
+	channels := make([]string, len(pm.Status.Channels))
+	for i, ch := range pm.Status.Channels {
+		n := ch.Name
+		if ch.IsDefaultChannel(*pm) {
+			n += " (default)"
+		}
+		if channel == ch.Name {
+			n += " (shown)"
+		}
+		channels[i] = n
+	}
+
+	return channels
+}

internal/cmd/root.go

@@ -40,6 +40,7 @@ operators from the installed catalogs.`,
 		newOperatorUninstallCmd(&cfg),
 		newOperatorListCmd(&cfg),
 		newOperatorListAvailableCmd(&cfg),
+		newOperatorDescribeCmd(&cfg),
 		newVersionCmd(),
 	)