redis-scanstreams

redis-scanstreams
=====



Provides a streaming interface to the Redis \*SCAN commands.

Replaces the SCAN, SSCAN, HSCAN, and ZSCAN methods on the node_redis client with streaming versions.

You can read more about SCAN here.

Example: Use with terminus

``javascript
var redis = require("redis")

// replace the methods for any clients
require("redis-scanstreams")(redis)

var client = redis.createClient()
var tail = require("terminus").tail

client.scan()
.pipe(tail({objectMode: true}, console.log))
`

Example: Use with stream-to-array


You can use stream-to-array to concatenate the Redis scan results into a single array.
`javascript
var redis = require("redis")

// replace the methods for any clients
require("redis-scanstreams")(redis)

var client = redis.createClient()
var toArray = require('stream-to-array')

toArray(client.scan(), function(err, arr) {
if (err)
throw err;

console.log(arr)
})
`

API
===

scanStreams(redis_library)
---

Replaces the \SCAN methods in the provided library. Assumes node_redis or a library that similarly exposes the RedisClient type which has the \SCAN methods.

client.scan(options)
---

Calls the scan command, walking the cursor through the entire keyspace. Returns a stream.Readable containing the Redis keyspace.

Options:
* pattern: the pattern to match keys against
* count: how many (max estimate) records to return per batch

e.g.
`js
client.scan({pattern: "key:*", count: 1000})
`

client.sscan(key, options)
---

Calls the sscan command on key key. Key must be a Redis Set. Options are identical to SCAN. Provides a stream.Readable containing set members.

client.hscan(key, options)
---

Calls the hscan command on key key. Key must be a Redis Hash. Options are identical to SCAN. Provides a stream.Readable containing hash key/value pairs, i.e.:

`js
[
{key: "hash_key_1", value: "value at hash_key_1"},
{key: "hash_key_2", value: "value at hash_key_2"},
...
]
`

client.zscan(key, options)
---

Calls the zscan command on key key. Key must be a Redis Zset. Options are identical to SCAN. Provides a stream.Readable containing hash member/score pairs, i.e.:

`js
[
{key: "zset_member_1", value: "score for zset_member_1"},
{key: "zset_member_2", value: "score for zset_member_2"},
...
]
``

LICENSE
=======

MIT