open-nomad/command/node_config.go

package command

import (
	"fmt"
	"strings"

	"github.com/posener/complete"
)

type NodeConfigCommand struct {
	Meta
}

func (c *NodeConfigCommand) Help() string {
	helpText := `
Usage: nomad node config [options]

  View or modify a client node's configuration details. This command only works
  on client nodes, and can be used to update the running client configurations
  it supports.

  The arguments behave differently depending on the flags given. See each
  flag's description for its specific requirements.

General Options:

  ` + generalOptionsUsage() + `

Client Config Options:

  -servers
    List the known server addresses of the client node. Client
    nodes do not participate in the gossip pool, and instead
    register with these servers periodically over the network.

  -update-servers
    Updates the client's server list using the provided
    arguments. Multiple server addresses may be passed using
    multiple arguments. IMPORTANT: When updating the servers
    list, you must specify ALL of the server nodes you wish
    to configure. The set is updated atomically.

    Example:
      $ nomad node config -update-servers foo:4647 bar:4647
`
	return strings.TrimSpace(helpText)
}

func (c *NodeConfigCommand) Synopsis() string {
	return "View or modify client configuration details"
}

func (c *NodeConfigCommand) Name() string { return "node config" }

func (c *NodeConfigCommand) Run(args []string) int {
	var listServers, updateServers bool

	flags := c.Meta.FlagSet(c.Name(), FlagSetClient)
	flags.Usage = func() { c.Ui.Output(c.Help()) }
	flags.BoolVar(&listServers, "servers", false, "")
	flags.BoolVar(&updateServers, "update-servers", false, "")

	if err := flags.Parse(args); err != nil {
		return 1
	}
	args = flags.Args()

	// Check the flags for misuse
	if !listServers && !updateServers {
		c.Ui.Error("The '-servers' or '-update-servers' flag(s) must be set")
		c.Ui.Error(commandErrorText(c))
		return 1
	}

	// Get the HTTP client
	client, err := c.Meta.Client()
	if err != nil {
		c.Ui.Error(fmt.Sprintf("Error initializing client: %s", err))
		return 1
	}

	if updateServers {
		// Get the server addresses
		if len(args) == 0 {
			c.Ui.Error("If the '-update-servers' flag is set, at least one server argument must be provided")
			c.Ui.Error(commandErrorText(c))
			return 1
		}

		// Set the servers list
		if err := client.Agent().SetServers(args); err != nil {
			c.Ui.Error(fmt.Sprintf("Error updating server list: %s", err))
			return 1
		}
		c.Ui.Output(fmt.Sprint("Updated server list"))
		return 0
	}

	if listServers {
		// Query the current server list
		servers, err := client.Agent().Servers()
		if err != nil {
			c.Ui.Error(fmt.Sprintf("Error querying server list: %s", err))
			return 1
		}

		// Print the results
		for _, server := range servers {
			c.Ui.Output(server)
		}
		return 0
	}

	// Should not make it this far
	return 1
}

func (c *NodeConfigCommand) AutocompleteFlags() complete.Flags {
	return mergeAutocompleteFlags(c.Meta.AutocompleteFlags(FlagSetClient),
		complete.Flags{
			"-servers":        complete.PredictNothing,
			"-update-servers": complete.PredictAnything,
		})
}

func (c *NodeConfigCommand) AutocompleteArgs() complete.Predictor {
	return complete.PredictNothing
}