open-nomad/command/agent_monitor.go

163 lines
3.6 KiB
Go

// Copyright (c) HashiCorp, Inc.
// SPDX-License-Identifier: MPL-2.0
package command
import (
"fmt"
"io"
"os"
"os/signal"
"strconv"
"strings"
"syscall"
"time"
"github.com/hashicorp/nomad/api"
"github.com/mitchellh/cli"
)
type MonitorCommand struct {
Meta
// Below this point is where CLI flag options are stored.
logLevel string
nodeID string
serverID string
logJSON bool
logIncludeLocation bool
}
func (c *MonitorCommand) Help() string {
helpText := `
Usage: nomad monitor [options]
Stream log messages of a nomad agent. The monitor command lets you
listen for log levels that may be filtered out of the Nomad agent. For
example your agent may only be logging at INFO level, but with the monitor
command you can set -log-level DEBUG
When ACLs are enabled, this command requires a token with the 'agent:read'
capability.
General Options:
` + generalOptionsUsage(usageOptsDefault|usageOptsNoNamespace) + `
Monitor Specific Options:
-log-level <level>
Sets the log level to monitor (default: INFO)
-log-include-location
Include file and line information in each log line. The default is false.
-node-id <node-id>
Sets the specific node to monitor
-server-id <server-id>
Sets the specific server to monitor
-json
Sets log output to JSON format
`
return strings.TrimSpace(helpText)
}
func (c *MonitorCommand) Synopsis() string {
return "Stream logs from a Nomad agent"
}
func (c *MonitorCommand) Name() string { return "monitor" }
func (c *MonitorCommand) Run(args []string) int {
c.Ui = &cli.PrefixedUi{
OutputPrefix: " ",
InfoPrefix: " ",
ErrorPrefix: "==> ",
Ui: c.Ui,
}
flags := c.Meta.FlagSet(c.Name(), FlagSetClient)
flags.Usage = func() { c.Ui.Output(c.Help()) }
flags.StringVar(&c.logLevel, "log-level", "", "")
flags.BoolVar(&c.logIncludeLocation, "log-include-location", false, "")
flags.StringVar(&c.nodeID, "node-id", "", "")
flags.StringVar(&c.serverID, "server-id", "", "")
flags.BoolVar(&c.logJSON, "json", false, "")
if err := flags.Parse(args); err != nil {
return 1
}
args = flags.Args()
if l := len(args); l != 0 {
c.Ui.Error("This command takes no arguments")
c.Ui.Error(commandErrorText(c))
return 1
}
client, err := c.Meta.Client()
if err != nil {
c.Ui.Error(fmt.Sprintf("Error initializing client: %s", err))
c.Ui.Error(commandErrorText(c))
return 1
}
// Query the node info and lookup prefix
if c.nodeID != "" {
c.nodeID, err = lookupNodeID(client.Nodes(), c.nodeID)
if err != nil {
c.Ui.Error(err.Error())
return 1
}
}
params := map[string]string{
"log_level": c.logLevel,
"node_id": c.nodeID,
"server_id": c.serverID,
"log_json": strconv.FormatBool(c.logJSON),
"log_include_location": strconv.FormatBool(c.logIncludeLocation),
}
query := &api.QueryOptions{
Params: params,
}
eventDoneCh := make(chan struct{})
frames, errCh := client.Agent().Monitor(eventDoneCh, query)
select {
case err := <-errCh:
c.Ui.Error(fmt.Sprintf("Error starting monitor: %s", err))
c.Ui.Error(commandErrorText(c))
return 1
default:
}
// Create a reader
var r io.ReadCloser
frameReader := api.NewFrameReader(frames, errCh, eventDoneCh)
frameReader.SetUnblockTime(500 * time.Millisecond)
r = frameReader
defer r.Close()
signalCh := make(chan os.Signal, 1)
signal.Notify(signalCh, os.Interrupt, syscall.SIGTERM)
go func() {
<-signalCh
// End the streaming
r.Close()
}()
_, err = io.Copy(os.Stdout, r)
if err != nil {
c.Ui.Error(fmt.Sprintf("error monitoring logs: %s", err))
return 1
}
return 0
}