redis-scanstreams

A streaming interface to the Redis SCAN (SCAN, SSCAN, HSCAN, ZSCAN) commands in Redis 2.8.x+

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

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.

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(errarr) {
  if (err)
    throw err;
 
  console.log(arr)
})

API

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.

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.

client.scan({pattern: "key:*", count: 1000})

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.

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.:

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

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.:

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

LICENSE

MIT