package put import ( "encoding/base64" "flag" "fmt" "io" "github.com/hashicorp/consul/api" "github.com/hashicorp/consul/command/flags" "github.com/hashicorp/consul/command/helpers" "github.com/mitchellh/cli" ) func New(ui cli.Ui) *cmd { c := &cmd{UI: ui} c.init() return c } type cmd struct { UI cli.Ui flags *flag.FlagSet http *flags.HTTPFlags help string // flags cas bool kvflags uint64 base64encoded bool modifyIndex uint64 session string acquire bool release bool // testStdin is the input for testing. testStdin io.Reader } func (c *cmd) init() { c.flags = flag.NewFlagSet("", flag.ContinueOnError) c.flags.BoolVar(&c.cas, "cas", false, "Perform a Check-And-Set operation. Specifying this value also "+ "requires the -modify-index flag to be set. The default value "+ "is false.") c.flags.Uint64Var(&c.kvflags, "flags", 0, "Unsigned integer value to assign to this key-value pair. This "+ "value is not read by Consul, so clients can use this value however "+ "makes sense for their use case. The default value is 0 (no flags).") c.flags.BoolVar(&c.base64encoded, "base64", false, "Treat the data as base 64 encoded. The default value is false.") c.flags.Uint64Var(&c.modifyIndex, "modify-index", 0, "Unsigned integer representing the ModifyIndex of the key. This is "+ "used in combination with the -cas flag.") c.flags.StringVar(&c.session, "session", "", "User-defined identifer for this session as a string. This is commonly "+ "used with the -acquire and -release operations to build robust locking, "+ "but it can be set on any key. The default value is empty (no session).") c.flags.BoolVar(&c.acquire, "acquire", false, "Obtain a lock on the key. If the key does not exist, this operation "+ "will create the key and obtain the lock. The session must already "+ "exist and be specified via the -session flag. The default value is false.") c.flags.BoolVar(&c.release, "release", false, "Forfeit the lock on the key at the given path. This requires the "+ "-session flag to be set. The key must be held by the session in order to "+ "be unlocked. The default value is false.") c.http = &flags.HTTPFlags{} flags.Merge(c.flags, c.http.ClientFlags()) flags.Merge(c.flags, c.http.ServerFlags()) flags.Merge(c.flags, c.http.NamespaceFlags()) c.help = flags.Usage(help, c.flags) } func (c *cmd) Run(args []string) int { if err := c.flags.Parse(args); err != nil { return 1 } // Check for arg validation args = c.flags.Args() key, data, err := c.dataFromArgs(args) if err != nil { c.UI.Error(fmt.Sprintf("Error! %s", err)) return 1 } dataBytes := []byte(data) if c.base64encoded { dataBytes, err = base64.StdEncoding.DecodeString(data) if err != nil { c.UI.Error(fmt.Sprintf("Error! Cannot base 64 decode data: %s", err)) } } // Session is required for release or acquire if (c.release || c.acquire) && c.session == "" { c.UI.Error("Error! Missing -session (required with -acquire and -release)") return 1 } // Create and test the HTTP client client, err := c.http.APIClient() if err != nil { c.UI.Error(fmt.Sprintf("Error connecting to Consul agent: %s", err)) return 1 } pair := &api.KVPair{ Key: key, ModifyIndex: c.modifyIndex, Flags: c.kvflags, Value: dataBytes, Session: c.session, } switch { case c.cas: ok, _, err := client.KV().CAS(pair, nil) if err != nil { c.UI.Error(fmt.Sprintf("Error! Did not write to %s: %s", key, err)) return 1 } if !ok && c.modifyIndex == 0 { c.UI.Error(fmt.Sprintf("Error! Did not write to %s: CAS performed with index=0 and key already exists.", key)) return 1 } if !ok { c.UI.Error(fmt.Sprintf("Error! Did not write to %s: CAS failed", key)) return 1 } c.UI.Info(fmt.Sprintf("Success! Data written to: %s", key)) return 0 case c.acquire: ok, _, err := client.KV().Acquire(pair, nil) if err != nil { c.UI.Error(fmt.Sprintf("Error! Failed writing data: %s", err)) return 1 } if !ok { c.UI.Error("Error! Did not acquire lock") return 1 } c.UI.Info(fmt.Sprintf("Success! Lock acquired on: %s", key)) return 0 case c.release: ok, _, err := client.KV().Release(pair, nil) if err != nil { c.UI.Error(fmt.Sprintf("Error! Failed writing data: %s", key)) return 1 } if !ok { c.UI.Error("Error! Did not release lock") return 1 } c.UI.Info(fmt.Sprintf("Success! Lock released on: %s", key)) return 0 default: if _, err := client.KV().Put(pair, nil); err != nil { c.UI.Error(fmt.Sprintf("Error! Failed writing data: %s", err)) return 1 } c.UI.Info(fmt.Sprintf("Success! Data written to: %s", key)) return 0 } } func (c *cmd) dataFromArgs(args []string) (string, string, error) { switch len(args) { case 0: return "", "", fmt.Errorf("Missing KEY argument") case 1: return args[0], "", nil case 2: default: return "", "", fmt.Errorf("Too many arguments (expected 1 or 2, got %d)", len(args)) } key := args[0] data, err := helpers.LoadDataSource(args[1], c.testStdin) if err != nil { return "", "", err } else { return key, data, nil } } func (c *cmd) Synopsis() string { return synopsis } func (c *cmd) Help() string { return c.help } const synopsis = "Sets or updates data in the KV store" const help = ` Usage: consul kv put [options] KEY [DATA] Writes the data to the given path in the key-value store. The data can be of any type. $ consul kv put config/redis/maxconns 5 The data can also be consumed from a file on disk by prefixing with the "@" symbol. For example: $ consul kv put config/program/license @license.lic Or it can be read from stdin using the "-" symbol: $ echo "abcd1234" | consul kv put config/program/license - The DATA argument itself is optional. If omitted, this will create an empty key-value pair at the specified path: $ consul kv put webapp/beta/active If the -base64 flag is specified, the data will be treated as base 64 encoded. To perform a Check-And-Set operation, specify the -cas flag with the appropriate -modify-index flag corresponding to the key you want to perform the CAS operation on: $ consul kv put -cas -modify-index=844 config/redis/maxconns 5 Additional flags and more advanced use cases are detailed below. `