etcdctlv3: interactive_v3 get command update

This commit is contained in:
sharat 2016-09-26 15:54:22 +05:30
parent 06546cf100
commit 595743651b

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@ -4,7 +4,7 @@ Users mostly interact with etcd by putting or getting the value of a key. This s
By default, etcdctl talks to the etcd server with the v2 API for backward compatibility. For etcdctl to speak to etcd using the v3 API, the API version must be set to version 3 via the `ETCDCTL_API` environment variable. By default, etcdctl talks to the etcd server with the v2 API for backward compatibility. For etcdctl to speak to etcd using the v3 API, the API version must be set to version 3 via the `ETCDCTL_API` environment variable.
``` bash ```bash
export ETCDCTL_API=3 export ETCDCTL_API=3
``` ```
@ -26,7 +26,7 @@ Applications store keys into the etcd cluster by writing to keys. Every stored k
Here is the command to set the value of key `foo` to `bar`: Here is the command to set the value of key `foo` to `bar`:
``` bash ```bash
$ etcdctl put foo bar $ etcdctl put foo bar
OK OK
``` ```
@ -62,6 +62,21 @@ foo
bar bar
``` ```
Here is the command to read the value of key `foo` in hex format:
```bash
$ etcdctl get foo --hex
\x66\x6f\x6f # Key
\x62\x61\x72 # Value
```
Here is the command to read only the value of key `foo`:
```bash
$ etcdctl get foo --print-value-only
bar
```
Here is the command to range over the keys from `foo` to `foo9`: Here is the command to range over the keys from `foo` to `foo9`:
```bash ```bash
@ -74,6 +89,16 @@ foo3
bar3 bar3
``` ```
Here is the command to range over the keys from `foo` to `foo9` limiting the number of results to 2:
```bash
$ etcdctl get foo foo9 --limit 2
foo
bar
foo1
bar1
```
## Read past version of keys ## Read past version of keys
Applications may want to read superseded versions of a key. For example, an application may wish to roll back to an old configuration by accessing an earlier version of a key. Alternatively, an application may want a consistent view over multiple keys through multiple requests by accessing key history. Applications may want to read superseded versions of a key. For example, an application may wish to roll back to an old configuration by accessing an earlier version of a key. Alternatively, an application may want a consistent view over multiple keys through multiple requests by accessing key history.
@ -82,10 +107,10 @@ Since every modification to the etcd cluster key-value store increments the glob
Suppose an etcd cluster already has the following keys: Suppose an etcd cluster already has the following keys:
``` bash ``` bash
$ etcdctl put foo bar # revision = 2 foo = bar # revision = 2
$ etcdctl put foo1 bar1 # revision = 3 foo1 = bar1 # revision = 3
$ etcdctl put foo bar_new # revision = 4 foo = bar_new # revision = 4
$ etcdctl put foo1 bar1_new # revision = 5 foo1 = bar1_new # revision = 5
``` ```
Here are an example to access the past versions of keys: Here are an example to access the past versions of keys:
@ -116,6 +141,28 @@ bar
$ etcdctl get --rev=1 foo foo9 # access the versions of keys at revision 1 $ etcdctl get --rev=1 foo foo9 # access the versions of keys at revision 1
``` ```
## Read keys which are greater than or equal to the byte value of the specified key
Applications may want to read keys which are greater than or equal to the byte value of the specified key.
Suppose an etcd cluster already has the following keys:
``` bash
a = 123
b = 456
z = 789
```
Here is the command to read keys which are greater than or equal to the byte value of key `b` :
```bash
$ etcdctl get --from-key b
b
456
z
789
```
## Delete keys ## Delete keys
Applications can delete a key or a range of keys from an etcd cluster. Applications can delete a key or a range of keys from an etcd cluster.