Add liqoctl info command

This patch introduces `liqoctl info`command to retrieve the status
of the current Liqo instance, plus some brief info about the
active peerings.

cmd/liqoctl/cmd/info.go

@@ -0,0 +1,129 @@
+// Copyright 2019-2024 The Liqo Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+package cmd
+
+import (
+	"context"
+	"os"
+
+	"github.com/spf13/cobra"
+
+	"github.com/liqotech/liqo/pkg/liqoctl/completion"
+	"github.com/liqotech/liqo/pkg/liqoctl/factory"
+	"github.com/liqotech/liqo/pkg/liqoctl/info"
+	"github.com/liqotech/liqo/pkg/liqoctl/info/localstatus"
+	"github.com/liqotech/liqo/pkg/liqoctl/output"
+	"github.com/liqotech/liqo/pkg/utils/args"
+)
+
+var outputFormat = args.NewEnum([]string{"json", "yaml"}, "")
+
+const liqoctlInfoLongHelp = `Show info about the current Liqo instance.
+
+Liqoctl provides a set of commands to verify the status of the Liqo control
+plane, its configuration, as well as the characteristics of the currently
+active peerings, and reports the outcome in human-readable or
+machine-readable format (either JSON or YAML).
+Additionally, via '--get', it allows to retrieve each single field of the reports
+using a query in dot notation (e.g. '--get field.subfield')
+
+This command shows information about the local cluster and checks the presence
+and the sanity of the Liqo namespace and the Liqo pods and some brief info about
+the active peerings and their status.
+
+Examples:
+  $ {{ .Executable }} info
+  $ {{ .Executable }} info --namespace liqo-system
+show the output in YAML format
+  $ {{ .Executable }} info -o yaml
+get a specific field
+  $ {{ .Executable }} info --get clusterid
+  $ {{ .Executable }} info --get network.podcidr
+`
+
+func infoPreRun(options *info.Options) {
+	// When the output is redirected to a file is desiderable that errors ends in the stderr output.
+	options.Printer.Error.Writer = os.Stderr
+	options.Printer.Warning.Writer = os.Stderr
+	// Configure output according to the provided parameter
+	options.Format = info.OutputFormat(outputFormat.Value)
+	// Force verbose when `get` is used to allow to retrieve also
+	// the info in the verbose output also when "--verbose" is not provided
+	if options.GetQuery != "" {
+		options.Verbose = true
+	}
+}
+
+func newPeerInfoCommand(ctx context.Context, f *factory.Factory, options *info.Options) *cobra.Command {
+	cmd := &cobra.Command{
+		Use:               "peer",
+		Short:             "Show additional info about one or more specific peerings",
+		Long:              WithTemplate(""),
+		Args:              cobra.MinimumNArgs(1),
+		ValidArgsFunction: completion.ClusterIDs(ctx, f, completion.NoLimit),
+
+		PreRun: func(_ *cobra.Command, _ []string) {
+			infoPreRun(options)
+		},
+
+		Run: func(_ *cobra.Command, clusterIds []string) {
+			output.ExitOnErr(options.RunPeerInfo(ctx, clusterIds))
+		},
+	}
+
+	return cmd
+}
+
+func newInfoCommand(ctx context.Context, f *factory.Factory) *cobra.Command {
+	options := info.NewOptions(f)
+
+	maincmd := &cobra.Command{
+		Use:   "info",
+		Short: "Show info about the current Liqo instance",
+		Long:  WithTemplate(liqoctlInfoLongHelp),
+		Args:  cobra.NoArgs,
+
+		PreRun: func(_ *cobra.Command, _ []string) {
+			infoPreRun(options)
+		},
+
+		Run: func(_ *cobra.Command, _ []string) {
+			// Set up checkers
+			checkers := []info.Checker{
+				&localstatus.InstallationChecker{},
+				&localstatus.HealthChecker{},
+			}
+			if options.Verbose {
+				checkers = append(checkers, &localstatus.NetworkChecker{})
+			}
+			checkers = append(checkers, &localstatus.PeeringChecker{})
+			output.ExitOnErr(options.RunInfo(ctx, checkers))
+		},
+	}
+
+	f.AddLiqoNamespaceFlag(maincmd.PersistentFlags())
+	maincmd.PersistentFlags().BoolVarP(&options.Verbose, "verbose", "v", false, "Make info more verbose")
+	maincmd.PersistentFlags().VarP(outputFormat, "output", "o", "Output format. Supported formats: json, yaml")
+	maincmd.PersistentFlags().StringVarP(&options.GetQuery, "get", "g", "",
+		"Path to the desired subfield in dot notation. Each part of the path corresponds to a key of the output structure")
+
+	f.Printer.CheckErr(maincmd.RegisterFlagCompletionFunc(factory.FlagNamespace, completion.Namespaces(ctx, f, completion.NoLimit)))
+	f.Printer.CheckErr(maincmd.RegisterFlagCompletionFunc("output", completion.Enumeration(outputFormat.Allowed)))
+
+	maincmd.AddCommand(newPeerInfoCommand(ctx, f, options))
+
+	return maincmd
+}

cmd/liqoctl/cmd/root.go

@@ -141,6 +141,7 @@ func NewRootCommand(ctx context.Context) *cobra.Command {
 	cmd.AddCommand(generate.NewGenerateCommand(ctx, liqoResources, f))
 	cmd.AddCommand(get.NewGetCommand(ctx, liqoResources, f))
 	cmd.AddCommand(delete.NewDeleteCommand(ctx, liqoResources, f))
+	cmd.AddCommand(newInfoCommand(ctx, f))
 	cmd.AddCommand(newTestCommand(ctx, f))
 
 	return cmd

go.mod

@@ -58,6 +58,7 @@ require (
 	sigs.k8s.io/aws-iam-authenticator v0.6.19
 	sigs.k8s.io/controller-runtime v0.18.5
 	sigs.k8s.io/sig-storage-lib-external-provisioner/v7 v7.0.1
+	sigs.k8s.io/yaml v1.4.0
 )
 
 require (
@@ -258,5 +259,4 @@ require (
 	sigs.k8s.io/kustomize/api v0.16.0 // indirect
 	sigs.k8s.io/kustomize/kyaml v0.16.0 // indirect
 	sigs.k8s.io/structured-merge-diff/v4 v4.4.1 // indirect
-	sigs.k8s.io/yaml v1.4.0 // indirect
 )

pkg/liqoctl/info/checker.go

@@ -0,0 +1,50 @@
+// Copyright 2019-2024 The Liqo Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package info
+
+import "context"
+
+// Checker is the interface to be implemented by all the checkers that
+// collect info about the current instance of Liqo.
+type Checker interface {
+	// Collect the data from the Liqo installation
+	Collect(ctx context.Context, options Options)
+	// Return the collected data using a user friendly output
+	Format(options Options) string
+	// Get the title of the section retrieve by the checker
+	GetTitle() string
+	// Get the id to be shown of machine readable output
+	GetID() string
+	// Get the data collected by the checker
+	GetData() interface{}
+	// Return the errors occurred during the collection of the data.
+	GetCollectionErrors() []error
+}
+
+// CheckerBase contains the common attributes and functions of the checkers.
+type CheckerBase struct {
+	collectionErrors []error
+}
+
+// AddCollectionError adds an error to the list of errors occurred while
+// collecting the info about a Liqo component.
+func (c *CheckerBase) AddCollectionError(err error) {
+	c.collectionErrors = append(c.collectionErrors, err)
+}
+
+// GetCollectionErrors returns the errors occurred during the collection of the data.
+func (c *CheckerBase) GetCollectionErrors() []error {
+	return c.collectionErrors
+}

pkg/liqoctl/info/doc.go

@@ -0,0 +1,17 @@
+// Copyright 2019-2024 The Liqo Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+// Package info contains the logic to show info about the current Liqo instance
+package info

pkg/liqoctl/info/handler.go

@@ -0,0 +1,100 @@
+// Copyright 2019-2024 The Liqo Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+package info
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/liqotech/liqo/pkg/liqoctl/factory"
+)
+
+// OutputFormat represents the format of the output of the command.
+type OutputFormat string
+
+const (
+	// JSON indicates that the output will be in JSON format.
+	JSON OutputFormat = "json"
+	// YAML indicates that the output will be in YAML format.
+	YAML OutputFormat = "yaml"
+)
+
+// LocalInfoQueryShortcuts contains shortcuts for the paths in the local info data.
+var LocalInfoQueryShortcuts = map[string]string{
+	"clusterid": "local.clusterid",
+}
+
+// Options encapsulates the arguments of the info command.
+type Options struct {
+	*factory.Factory
+
+	Verbose  bool
+	Format   OutputFormat
+	GetQuery string
+}
+
+// NewOptions returns a new Options struct.
+func NewOptions(f *factory.Factory) *Options {
+	return &Options{
+		Factory: f,
+	}
+}
+
+// RunInfo execute the `info` command.
+func (o *Options) RunInfo(ctx context.Context, checkers []Checker) error {
+	// Check whether Liqo is installed in the current cluster
+	if err := o.installationCheck(ctx); err != nil {
+		return err
+	}
+
+	// Start collecting the data via the checkers
+	for i := range checkers {
+		checkers[i].Collect(ctx, *o)
+		for _, err := range checkers[i].GetCollectionErrors() {
+			o.Printer.Warning.Println(err)
+		}
+	}
+
+	var err error
+	var output string
+	switch {
+	// If no format is specified, format and print a user-friendly output
+	case o.Format == "" && o.GetQuery == "":
+		for i := range checkers {
+			o.Printer.BoxSetTitle(checkers[i].GetTitle())
+			o.Printer.BoxPrintln(checkers[i].Format(*o))
+		}
+		return nil
+	// If query specified try to retrieve the field from the output
+	case o.GetQuery != "":
+		output, err = o.sPrintField(o.GetQuery, checkers, LocalInfoQueryShortcuts)
+	default:
+		output, err = o.sPrintMachineReadable(checkers)
+	}
+
+	if err != nil {
+		o.Printer.Error.Println(err)
+	} else {
+		fmt.Println(output)
+	}
+
+	return err
+}
+
+// RunPeerInfo execute the `info peer` command.
+func (o *Options) RunPeerInfo(_ context.Context, _ []string) error {
+	panic("Not implemented")
+}

pkg/liqoctl/info/localstatus/doc.go

@@ -0,0 +1,17 @@
+// Copyright 2019-2024 The Liqo Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+// Package localstatus contains the logic to retrieve info about the local Liqo instance
+package localstatus