logs.go

/*
Copyright 2018 The Knative 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 service

import (
	"fmt"

	"github.com/cppforlife/go-cli-ui/ui"
	cmdcore "github.com/cppforlife/knctl/pkg/knctl/cmd/core"
	cmdflags "github.com/cppforlife/knctl/pkg/knctl/cmd/flags"
	"github.com/cppforlife/knctl/pkg/knctl/logs"
	ctlservice "github.com/cppforlife/knctl/pkg/knctl/service"
	"github.com/spf13/cobra"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
)

type LogsOptions struct {
	ui            ui.UI
	depsFactory   cmdcore.DepsFactory
	cancelSignals cmdcore.CancelSignals

	ServiceFlags cmdflags.ServiceFlags

	Follow bool
	Lines  int64
}

func NewLogsOptions(ui ui.UI, depsFactory cmdcore.DepsFactory, cancelSignals cmdcore.CancelSignals) *LogsOptions {
	return &LogsOptions{ui: ui, depsFactory: depsFactory, cancelSignals: cancelSignals}
}

func NewLogsCmd(o *LogsOptions, flagsFactory cmdcore.FlagsFactory) *cobra.Command {
	cmd := &cobra.Command{
		Use:   "logs",
		Short: "Print service logs",
		Long:  "Print service logs of all active pods for a service",
		Example: `
  # Fetch last 10 log lines for service 'svc1' in namespace 'ns1' 
  knctl logs -s svc1 -n ns1

  # Follow logs for service 'svc1' in namespace 'ns1' 
  knctl logs -f -s svc1 -n ns1`,
		Annotations: map[string]string{
			cmdcore.BasicHelpGroup.Key: cmdcore.BasicHelpGroup.Value,
		},
		RunE: func(_ *cobra.Command, _ []string) error { return o.Run() },
	}
	o.ServiceFlags.Set(cmd, flagsFactory)

	cmd.Flags().BoolVarP(&o.Follow, "follow", "f", false, "As new revisions are added, new pod logs will be printed")
	cmd.Flags().Int64VarP(&o.Lines, "lines", "l", 10, "Number of lines")

	return cmd
}

func (o *LogsOptions) Run() error {
	if !o.Follow && o.Lines <= 0 {
		return fmt.Errorf("Expected --lines to be greater than zero since --follow is not specified")
	}

	tailOpts := logs.PodLogOpts{Follow: o.Follow}

	if !o.Follow {
		tailOpts.Lines = &o.Lines
	}

	servingClient, err := o.depsFactory.ServingClient()
	if err != nil {
		return err
	}

	service, err := servingClient.ServingV1alpha1().Services(o.ServiceFlags.NamespaceFlags.Name).Get(o.ServiceFlags.Name, metav1.GetOptions{})
	if err != nil {
		return err
	}

	coreClient, err := o.depsFactory.CoreClient()
	if err != nil {
		return err
	}

	podWatcher := ctlservice.NewServicePodWatcher(service, servingClient, coreClient, o.ui)
	cancelCh := make(chan struct{})

	o.cancelSignals.Watch(func() {
		close(cancelCh)
	})

	return LogsView{tailOpts, podWatcher, coreClient, o.ui}.Show(cancelCh)
}