github.com/makyo/juju@v0.0.0-20160425123129-2608902037e9/cmd/juju/service/removeunit.go (about)

     1  // Copyright 2012, 2013 Canonical Ltd.
     2  // Licensed under the AGPLv3, see LICENCE file for details.
     3  
     4  package service
     5  
     6  import (
     7  	"fmt"
     8  
     9  	"github.com/juju/cmd"
    10  	"github.com/juju/errors"
    11  	"github.com/juju/names"
    12  
    13  	apiservice "github.com/juju/juju/api/service"
    14  	"github.com/juju/juju/cmd/juju/block"
    15  	"github.com/juju/juju/cmd/modelcmd"
    16  )
    17  
    18  // NewRemoveUnitCommand returns a command which removes a service's units.
    19  func NewRemoveUnitCommand() cmd.Command {
    20  	return modelcmd.Wrap(&removeUnitCommand{})
    21  }
    22  
    23  // removeUnitCommand is responsible for destroying service units.
    24  type removeUnitCommand struct {
    25  	modelcmd.ModelCommandBase
    26  	UnitNames []string
    27  }
    28  
    29  const removeUnitDoc = `
    30  Remove service units from the model.
    31  
    32  If this is the only unit running, the machine on which
    33  the unit is hosted will also be destroyed, if possible.
    34  The machine will be destroyed if:
    35  - it is not a controller
    36  - it is not hosting any Juju managed containers
    37  `
    38  
    39  func (c *removeUnitCommand) Info() *cmd.Info {
    40  	return &cmd.Info{
    41  		Name:    "remove-unit",
    42  		Args:    "<unit> [...]",
    43  		Purpose: "remove service units from the model",
    44  		Doc:     removeUnitDoc,
    45  		Aliases: []string{"destroy-unit"},
    46  	}
    47  }
    48  
    49  func (c *removeUnitCommand) Init(args []string) error {
    50  	c.UnitNames = args
    51  	if len(c.UnitNames) == 0 {
    52  		return fmt.Errorf("no units specified")
    53  	}
    54  	for _, name := range c.UnitNames {
    55  		if !names.IsValidUnit(name) {
    56  			return fmt.Errorf("invalid unit name %q", name)
    57  		}
    58  	}
    59  	return nil
    60  }
    61  
    62  func (c *removeUnitCommand) getAPI() (ServiceAPI, error) {
    63  	root, err := c.NewAPIRoot()
    64  	if err != nil {
    65  		return nil, errors.Trace(err)
    66  	}
    67  	return apiservice.NewClient(root), nil
    68  }
    69  
    70  // Run connects to the environment specified on the command line and destroys
    71  // units therein.
    72  func (c *removeUnitCommand) Run(_ *cmd.Context) error {
    73  	client, err := c.getAPI()
    74  	if err != nil {
    75  		return err
    76  	}
    77  	defer client.Close()
    78  	return block.ProcessBlockedError(client.DestroyUnits(c.UnitNames...), block.BlockRemove)
    79  }