github.com/cloud-green/juju@v0.0.0-20151002100041-a00291338d3d/worker/uniter/runner/jujuc/storage-get.go (about)

     1  // Copyright 2015 Canonical Ltd.
     2  // Licensed under the AGPLv3, see LICENCE file for details.
     3  
     4  package jujuc
     5  
     6  import (
     7  	"github.com/juju/cmd"
     8  	"github.com/juju/errors"
     9  	"github.com/juju/names"
    10  	"launchpad.net/gnuflag"
    11  
    12  	"github.com/juju/juju/apiserver/params"
    13  )
    14  
    15  // StorageGetCommand implements the storage-get command.
    16  type StorageGetCommand struct {
    17  	cmd.CommandBase
    18  	ctx             Context
    19  	storageTag      names.StorageTag
    20  	storageTagProxy gnuflag.Value
    21  	key             string
    22  	out             cmd.Output
    23  }
    24  
    25  func NewStorageGetCommand(ctx Context) (cmd.Command, error) {
    26  	c := &StorageGetCommand{ctx: ctx}
    27  	sV, err := newStorageIdValue(ctx, &c.storageTag)
    28  	if err != nil {
    29  		return nil, errors.Trace(err)
    30  	}
    31  	c.storageTagProxy = sV
    32  	return c, nil
    33  }
    34  
    35  func (c *StorageGetCommand) Info() *cmd.Info {
    36  	doc := `
    37  When no <key> is supplied, all keys values are printed.
    38  `
    39  	return &cmd.Info{
    40  		Name:    "storage-get",
    41  		Args:    "[<key>]",
    42  		Purpose: "print information for storage instance with specified id",
    43  		Doc:     doc,
    44  	}
    45  }
    46  
    47  func (c *StorageGetCommand) SetFlags(f *gnuflag.FlagSet) {
    48  	c.out.AddFlags(f, "smart", cmd.DefaultFormatters)
    49  	f.Var(c.storageTagProxy, "s", "specify a storage instance by id")
    50  }
    51  
    52  func (c *StorageGetCommand) Init(args []string) error {
    53  	if c.storageTag == (names.StorageTag{}) {
    54  		return errors.New("no storage instance specified")
    55  	}
    56  	key, err := cmd.ZeroOrOneArgs(args)
    57  	if err != nil {
    58  		return err
    59  	}
    60  	c.key = key
    61  	return nil
    62  }
    63  
    64  func storageKindString(k params.StorageKind) string {
    65  	switch k {
    66  	case params.StorageKindBlock:
    67  		return "block"
    68  	case params.StorageKindFilesystem:
    69  		return "filesystem"
    70  	}
    71  	return "unknown"
    72  }
    73  
    74  func (c *StorageGetCommand) Run(ctx *cmd.Context) error {
    75  	storage, err := c.ctx.Storage(c.storageTag)
    76  	if err != nil {
    77  		return errors.Trace(err)
    78  	}
    79  	values := map[string]interface{}{
    80  		"kind":     storage.Kind().String(),
    81  		"location": storage.Location(),
    82  	}
    83  	if c.key == "" {
    84  		return c.out.Write(ctx, values)
    85  	}
    86  	if value, ok := values[c.key]; ok {
    87  		return c.out.Write(ctx, value)
    88  	}
    89  	return errors.Errorf("invalid storage attribute %q", c.key)
    90  }