KV metadata in API

The current KV api is nice and simple for getting values:

>>> etcd.get("/key")
b"some-value"

It doesn't allow for retrieving the metadata about keys, however.

We need to figure out a nice api for showing all the data: key, create_revision, mod_revision, version, value, lease.

How other projects do it:

python-etcd

python-etcd returns an object for all reads containing a .value attribute to read the actual value:

client.read('/nodes/n2').value
#recursively read a directory
r = client.read('/nodes', recursive=True, sorted=True)
for child in r.children:
    print("%s: %s" % (child.key,child.value))

kazoo (zookeeper)

kazoo returns two values, the data and the node information:

data, stat = zk.get("/my/favorite")
print("Version: %s, data: %s" % (stat.version, data.decode("utf-8")))

python-consul

python-consul is pretty ugly:

index, data = consul.Consul().kv.get('foo', index=index)
print data['Value']

data is a dict that looks like:

{
    "CreateIndex": 100,
    "ModifyIndex": 200,
    "LockIndex": 200,
    "Key": "foo",
    "Flags": 0,
    "Value": "bar",
    "Session": "adf4238a-882b-9ddc-4a9d-5b6758e4159e"
}

Non viene indicato alcun file sorgente né alcun test. Inizia individuando l’API Python KV get attuale e confronta il suo valore restituito con i campi dei metadati elencati nell’issue; il lavoro è terminato quando un’API concordata espone key, create_revision, mod_revision, version, value e lease.