class Redis
Constants
- Boolify
Commands returning 1 for true and 0 for false may be executed in a pipeline where the method call will return nil. Propagate the nil instead of falsely returning false.
- BoolifySet
- Floatify
- FloatifyPairs
- Hashify
- VERSION
Attributes
Public Class Methods
@deprecated The preferred way to create a new client object is using `#new`.
This method does not actually establish a connection to Redis, in contrary to what you might expect.
# File lib/redis.rb, line 15 def self.connect(options = {}) new(options) end
# File lib/redis.rb, line 19 def self.current @current ||= Redis.new end
# File lib/redis.rb, line 23 def self.current=(redis) @current = redis end
# File lib/redis.rb, line 6 def self.deprecate(message, trace = caller[0]) $stderr.puts "\n#{message} (in #{trace})" end
Create a new client instance
@param [Hash] options @option options [String] :url (value of the environment variable REDIS_URL) a Redis URL, for a TCP connection: `redis://:@[hostname]:/[db]` (password, port and database are optional), for a unix socket connection: `unix://[path to Redis socket]`. This overrides all other options. @option options [String] :host (“127.0.0.1”) server hostname @option options [Fixnum] :port (6379) server port @option options [String] :path path to server socket (overrides host and port) @option options [Float] :timeout (5.0) timeout in seconds @option options [Float] :connect_timeout (same as timeout) timeout for initial connect in seconds @option options [String] :password Password to authenticate against server @option options [Fixnum] :db (0) Database to select after initial connect @option options [Symbol] :driver Driver to use, currently supported: `:ruby`, `:hiredis`, `:synchrony` @option options [String] :id ID for the client connection, assigns name to current connection by sending `CLIENT SETNAME` @option options [Hash, Fixnum] :tcp_keepalive Keepalive values, if Fixnum `intvl` and `probe` are calculated based on the value, if Hash `time`, `intvl` and `probes` can be specified as a Fixnum @option options [Fixnum] :reconnect_attempts Number of attempts trying to connect @option options [Boolean] :inherit_socket (false) Whether to use socket in forked process or not @option options [Array] :sentinels List of sentinels to contact @option options [Symbol] :role (:master) Role to fetch via Sentinel, either `:master` or `:slave`
@return [Redis] a new client instance
# File lib/redis.rb, line 49 def initialize(options = {}) @options = options.dup @original_client = @client = Client.new(options) @queue = Hash.new { |h, k| h[k] = [] } super() # Monitor#initialize end
Public Instance Methods
# File lib/redis.rb, line 1116 def _bpop(cmd, args) options = {} case args.last when Hash options = args.pop when Integer # Issue deprecation notice in obnoxious mode... options[:timeout] = args.pop end if args.size > 1 # Issue deprecation notice in obnoxious mode... end keys = args.flatten timeout = options[:timeout] || 0 synchronize do |client| command = [cmd, keys, timeout] timeout += client.timeout if timeout > 0 client.call_with_timeout(command, timeout) end end
# File lib/redis.rb, line 2390 def _eval(cmd, args) script = args.shift options = args.pop if args.last.is_a?(Hash) options ||= {} keys = args.shift || options[:keys] || [] argv = args.shift || options[:argv] || [] synchronize do |client| client.call([cmd, script, keys.length] + keys + argv) end end
# File lib/redis.rb, line 2453 def _scan(command, cursor, args, options = {}, &block) # SSCAN/ZSCAN/HSCAN already prepend the key to +args+. args << cursor if match = options[:match] args.concat(["MATCH", match]) end if count = options[:count] args.concat(["COUNT", count]) end synchronize do |client| client.call([command] + args, &block) end end
Append a value to a key.
@param [String] key @param [String] value value to append @return [Fixnum] length of the string after appending
# File lib/redis.rb, line 957 def append(key, value) synchronize do |client| client.call([:append, key, value]) end end
Authenticate to the server.
@param [String] password must match the password specified in the
`requirepass` directive in the configuration file
@return [String] `OK`
# File lib/redis.rb, line 127 def auth(password) synchronize do |client| client.call([:auth, password]) end end
Asynchronously rewrite the append-only file.
@return [String] `OK`
# File lib/redis.rb, line 180 def bgrewriteaof synchronize do |client| client.call([:bgrewriteaof]) end end
Asynchronously save the dataset to disk.
@return [String] `OK`
# File lib/redis.rb, line 189 def bgsave synchronize do |client| client.call([:bgsave]) end end
Count the number of set bits in a range of the string value stored at key.
@param [String] key @param [Fixnum] start start index @param [Fixnum] stop stop index @return [Fixnum] the number of bits set to 1
# File lib/redis.rb, line 969 def bitcount(key, start = 0, stop = -1) synchronize do |client| client.call([:bitcount, key, start, stop]) end end
Perform a bitwise operation between strings and store the resulting string in a key.
@param [String] operation e.g. `and`, `or`, `xor`, `not` @param [String] destkey destination key @param [String, Array<String>] keys one or more source keys to perform `operation` @return [Fixnum] the length of the string stored in `destkey`
# File lib/redis.rb, line 981 def bitop(operation, destkey, *keys) synchronize do |client| client.call([:bitop, operation, destkey] + keys) end end
Return the position of the first bit set to 1 or 0 in a string.
@param [String] key @param [Fixnum] bit whether to look for the first 1 or 0 bit @param [Fixnum] start start index @param [Fixnum] stop stop index @return [Fixnum] the position of the first 1/0 bit.
-1 if looking for 1 and it is not found or start and stop are given.
# File lib/redis.rb, line 995 def bitpos(key, bit, start=nil, stop=nil) if stop and not start raise(ArgumentError, 'stop parameter specified without start parameter') end synchronize do |client| command = [:bitpos, key, bit] command << start if start command << stop if stop client.call(command) end end
Remove and get the first element in a list, or block until one is available.
@example With timeout
list, element = redis.blpop("list", :timeout => 5) # => nil on timeout # => ["list", "element"] on success
@example Without timeout
list, element = redis.blpop("list") # => ["list", "element"]
@example Blocking pop on multiple lists
list, element = redis.blpop(["list", "another_list"]) # => ["list", "element"]
@param [String, Array<String>] keys one or more keys to perform the
blocking pop on
@param [Hash] options
- `:timeout => Fixnum`: timeout in seconds, defaults to no timeout
@return [nil, [String, String]]
- `nil` when the operation timed out - tuple of the list that was popped from and element was popped otherwise
# File lib/redis.rb, line 1162 def blpop(*args) _bpop(:blpop, args) end
Remove and get the last element in a list, or block until one is available.
@param [String, Array<String>] keys one or more keys to perform the
blocking pop on
@param [Hash] options
- `:timeout => Fixnum`: timeout in seconds, defaults to no timeout
@return [nil, [String, String]]
- `nil` when the operation timed out - tuple of the list that was popped from and element was popped otherwise
@see blpop
# File lib/redis.rb, line 1178 def brpop(*args) _bpop(:brpop, args) end
Pop a value from a list, push it to another list and return it; or block until one is available.
@param [String] source source key @param [String] destination destination key @param [Hash] options
- `:timeout => Fixnum`: timeout in seconds, defaults to no timeout
@return [nil, String]
- `nil` when the operation timed out - the element was popped and pushed otherwise
# File lib/redis.rb, line 1193 def brpoplpush(source, destination, options = {}) case options when Integer # Issue deprecation notice in obnoxious mode... options = { :timeout => options } end timeout = options[:timeout] || 0 synchronize do |client| command = [:brpoplpush, source, destination, timeout] timeout += client.timeout if timeout > 0 client.call_with_timeout(command, timeout) end end
Sends a command to Redis and returns its reply.
Replies are converted to Ruby objects according to the RESP protocol, so you can expect a Ruby array, integer or nil when Redis sends one. Higher level transformations, such as converting an array of pairs into a Ruby hash, are up to consumers.
Redis error replies are raised as Ruby exceptions.
# File lib/redis.rb, line 92 def call(*command) synchronize do |client| client.call(command) end end
Disconnect the client as quickly and silently as possible.
# File lib/redis.rb, line 79 def close @original_client.disconnect end
Sends all commands in the queue.
See redis.io/topics/pipelining for more details.
# File lib/redis.rb, line 112 def commit synchronize do |client| begin client.call_pipelined(@queue[Thread.current.object_id]) ensure @queue.delete(Thread.current.object_id) end end end
Get or set server configuration parameters.
@param [Symbol] action e.g. `:get`, `:set`, `:resetstat` @return [String, Hash] string reply, or hash when retrieving more than one
property with `CONFIG GET`
# File lib/redis.rb, line 200 def config(action, *args) synchronize do |client| client.call([:config, action] + args) do |reply| if reply.kind_of?(Array) && action == :get Hashify.call(reply) else reply end end end end
Test whether or not the client is connected
# File lib/redis.rb, line 74 def connected? @original_client.connected? end
# File lib/redis.rb, line 2703 def connection { :host => @original_client.host, :port => @original_client.port, :db => @original_client.db, :id => @original_client.id, :location => @original_client.location } end
Return the number of keys in the selected database.
@return [Fixnum]
# File lib/redis.rb, line 215 def dbsize synchronize do |client| client.call([:dbsize]) end end
# File lib/redis.rb, line 221 def debug(*args) synchronize do |client| client.call([:debug] + args) end end
Decrement the integer value of a key by one.
@example
redis.decr("value") # => 4
@param [String] key @return [Fixnum] value after decrementing it
# File lib/redis.rb, line 660 def decr(key) synchronize do |client| client.call([:decr, key]) end end
Decrement the integer value of a key by the given number.
@example
redis.decrby("value", 5) # => 0
@param [String] key @param [Fixnum] decrement @return [Fixnum] value after decrementing it
# File lib/redis.rb, line 675 def decrby(key, decrement) synchronize do |client| client.call([:decrby, key, decrement]) end end
Delete one or more keys.
@param [String, Array<String>] keys @return [Fixnum] number of keys that were deleted
# File lib/redis.rb, line 492 def del(*keys) synchronize do |client| client.call([:del] + keys) end end
Return a serialized version of the value stored at a key.
@param [String] key @return [String] serialized_value
# File lib/redis.rb, line 450 def dump(key) synchronize do |client| client.call([:dump, key]) end end
# File lib/redis.rb, line 2699 def dup self.class.new(@options) end
Echo the given string.
@param [String] value @return [String]
# File lib/redis.rb, line 157 def echo(value) synchronize do |client| client.call([:echo, value]) end end
Evaluate Lua script.
@example EVAL without KEYS nor ARGV
redis.eval("return 1") # => 1
@example EVAL with KEYS and ARGV as array arguments
redis.eval("return { KEYS, ARGV }", ["k1", "k2"], ["a1", "a2"]) # => [["k1", "k2"], ["a1", "a2"]]
@example EVAL with KEYS and ARGV in a hash argument
redis.eval("return { KEYS, ARGV }", :keys => ["k1", "k2"], :argv => ["a1", "a2"]) # => [["k1", "k2"], ["a1", "a2"]]
@param [Array<String>] keys optional array with keys to pass to the script @param [Array<String>] argv optional array with arguments to pass to the script @param [Hash] options
- `:keys => Array<String>`: optional array with keys to pass to the script - `:argv => Array<String>`: optional array with arguments to pass to the script
@return depends on the script
# File lib/redis.rb, line 2424 def eval(*args) _eval(:eval, args) end
Evaluate Lua script by its SHA.
@example EVALSHA without KEYS nor ARGV
redis.evalsha(sha) # => <depends on script>
@example EVALSHA with KEYS and ARGV as array arguments
redis.evalsha(sha, ["k1", "k2"], ["a1", "a2"]) # => <depends on script>
@example EVALSHA with KEYS and ARGV in a hash argument
redis.evalsha(sha, :keys => ["k1", "k2"], :argv => ["a1", "a2"]) # => <depends on script>
@param [Array<String>] keys optional array with keys to pass to the script @param [Array<String>] argv optional array with arguments to pass to the script @param [Hash] options
- `:keys => Array<String>`: optional array with keys to pass to the script - `:argv => Array<String>`: optional array with arguments to pass to the script
@return depends on the script
# File lib/redis.rb, line 2449 def evalsha(*args) _eval(:evalsha, args) end
Execute all commands issued after MULTI.
Only call this method when `#multi` was called *without* a block.
@return [nil, Array<…>]
- when commands were not executed, `nil` - when commands were executed, an array with their replies
# File lib/redis.rb, line 2322 def exec synchronize do |client| client.call([:exec]) end end
Determine if a key exists.
@param [String] key @return [Boolean]
# File lib/redis.rb, line 502 def exists(key) synchronize do |client| client.call([:exists, key], &Boolify) end end
Set a key's time to live in seconds.
@param [String] key @param [Fixnum] seconds time to live @return [Boolean] whether the timeout was set or not
# File lib/redis.rb, line 372 def expire(key, seconds) synchronize do |client| client.call([:expire, key, seconds], &Boolify) end end
Set the expiration for a key as a UNIX timestamp.
@param [String] key @param [Fixnum] unix_time expiry time specified as a UNIX timestamp @return [Boolean] whether the timeout was set or not
# File lib/redis.rb, line 383 def expireat(key, unix_time) synchronize do |client| client.call([:expireat, key, unix_time], &Boolify) end end
Remove all keys from all databases.
@return [String] `OK`
# File lib/redis.rb, line 230 def flushall synchronize do |client| client.call([:flushall]) end end
Remove all keys from the current database.
@return [String] `OK`
# File lib/redis.rb, line 239 def flushdb synchronize do |client| client.call([:flushdb]) end end
Get the value of a key.
@param [String] key @return [String]
# File lib/redis.rb, line 860 def get(key) synchronize do |client| client.call([:get, key]) end end
Returns the bit value at offset in the string value stored at key.
@param [String] key @param [Fixnum] offset bit offset @return [Fixnum] `0` or `1`
# File lib/redis.rb, line 946 def getbit(key, offset) synchronize do |client| client.call([:getbit, key, offset]) end end
Get a substring of the string stored at a key.
@param [String] key @param [Fixnum] start zero-based start offset @param [Fixnum] stop zero-based end offset. Use -1 for representing
the end of the string
@return [Fixnum] `0` or `1`
# File lib/redis.rb, line 923 def getrange(key, start, stop) synchronize do |client| client.call([:getrange, key, start, stop]) end end
Set the string value of a key and return its old value.
@param [String] key @param [String] value value to replace the current value with @return [String] the old value stored in the key, or `nil` if the key
did not exist
# File lib/redis.rb, line 1014 def getset(key, value) synchronize do |client| client.call([:getset, key, value.to_s]) end end
Delete one or more hash fields.
@param [String] key @param [String, Array<String>] field @return [Fixnum] the number of fields that were removed from the hash
# File lib/redis.rb, line 2056 def hdel(key, field) synchronize do |client| client.call([:hdel, key, field]) end end
Determine if a hash field exists.
@param [String] key @param [String] field @return [Boolean] whether or not the field exists in the hash
# File lib/redis.rb, line 2067 def hexists(key, field) synchronize do |client| client.call([:hexists, key, field], &Boolify) end end
Get the value of a hash field.
@param [String] key @param [String] field @return [String]
# File lib/redis.rb, line 2007 def hget(key, field) synchronize do |client| client.call([:hget, key, field]) end end
Get all the fields and values in a hash.
@param [String] key @return [Hash<String, String>]
# File lib/redis.rb, line 2121 def hgetall(key) synchronize do |client| client.call([:hgetall, key], &Hashify) end end
Increment the integer value of a hash field by the given integer number.
@param [String] key @param [String] field @param [Fixnum] increment @return [Fixnum] value of the field after incrementing it
# File lib/redis.rb, line 2079 def hincrby(key, field, increment) synchronize do |client| client.call([:hincrby, key, field, increment]) end end
Increment the numeric value of a hash field by the given float number.
@param [String] key @param [String] field @param [Float] increment @return [Float] value of the field after incrementing it
# File lib/redis.rb, line 2091 def hincrbyfloat(key, field, increment) synchronize do |client| client.call([:hincrbyfloat, key, field, increment], &Floatify) end end
Get all the fields in a hash.
@param [String] key @return [Array<String>]
# File lib/redis.rb, line 2101 def hkeys(key) synchronize do |client| client.call([:hkeys, key]) end end
Get the number of fields in a hash.
@param [String] key @return [Fixnum] number of fields in the hash
# File lib/redis.rb, line 1940 def hlen(key) synchronize do |client| client.call([:hlen, key]) end end
Get the values of all the given hash fields.
@example
redis.hmget("hash", "f1", "f2") # => ["v1", "v2"]
@param [String] key @param [Array<String>] fields array of fields @return [Array<String>] an array of values for the specified fields
@see mapped_hmget
# File lib/redis.rb, line 2024 def hmget(key, *fields, &blk) synchronize do |client| client.call([:hmget, key] + fields, &blk) end end
Set one or more hash values.
@example
redis.hmset("hash", "f1", "v1", "f2", "v2") # => "OK"
@param [String] key @param [Array<String>] attrs array of fields and values @return [String] `“OK”`
@see mapped_hmset
# File lib/redis.rb, line 1981 def hmset(key, *attrs) synchronize do |client| client.call([:hmset, key] + attrs) end end
Scan a hash
@example Retrieve the first batch of key/value pairs in a hash
redis.hscan("hash", 0)
@param [String, Integer] cursor the cursor of the iteration @param [Hash] options
- `:match => String`: only return keys matching the pattern - `:count => Integer`: return count keys at most per iteration
@return [String, Array<[String, String]>] the next cursor and all found keys
# File lib/redis.rb, line 2526 def hscan(key, cursor, options={}) _scan(:hscan, cursor, [key], options) do |reply| [reply[0], reply[1].each_slice(2).to_a] end end
Scan a hash
@example Retrieve all of the key/value pairs in a hash
redis.hscan_each("hash").to_a # => [["key70", "70"], ["key80", "80"]]
@param [Hash] options
- `:match => String`: only return keys matching the pattern - `:count => Integer`: return count keys at most per iteration
@return [Enumerator] an enumerator for all found keys
# File lib/redis.rb, line 2543 def hscan_each(key, options={}, &block) return to_enum(:hscan_each, key, options) unless block_given? cursor = 0 loop do cursor, values = hscan(key, cursor, options) values.each(&block) break if cursor == "0" end end
Set the string value of a hash field.
@param [String] key @param [String] field @param [String] value @return [Boolean] whether or not the field was *added* to the hash
# File lib/redis.rb, line 1952 def hset(key, field, value) synchronize do |client| client.call([:hset, key, field, value], &Boolify) end end
Set the value of a hash field, only if the field does not exist.
@param [String] key @param [String] field @param [String] value @return [Boolean] whether or not the field was *added* to the hash
# File lib/redis.rb, line 1964 def hsetnx(key, field, value) synchronize do |client| client.call([:hsetnx, key, field, value], &Boolify) end end
Get all the values in a hash.
@param [String] key @return [Array<String>]
# File lib/redis.rb, line 2111 def hvals(key) synchronize do |client| client.call([:hvals, key]) end end
# File lib/redis.rb, line 2691 def id @original_client.id end
Increment the integer value of a key by one.
@example
redis.incr("value") # => 6
@param [String] key @return [Fixnum] value after incrementing it
# File lib/redis.rb, line 689 def incr(key) synchronize do |client| client.call([:incr, key]) end end
Increment the integer value of a key by the given integer number.
@example
redis.incrby("value", 5) # => 10
@param [String] key @param [Fixnum] increment @return [Fixnum] value after incrementing it
# File lib/redis.rb, line 704 def incrby(key, increment) synchronize do |client| client.call([:incrby, key, increment]) end end
Increment the numeric value of a key by the given float number.
@example
redis.incrbyfloat("value", 1.23) # => 1.23
@param [String] key @param [Float] increment @return [Float] value after incrementing it
# File lib/redis.rb, line 719 def incrbyfloat(key, increment) synchronize do |client| client.call([:incrbyfloat, key, increment], &Floatify) end end
Get information and statistics about the server.
@param [String, Symbol] cmd e.g. “commandstats” @return [Hash<String, String>]
# File lib/redis.rb, line 249 def info(cmd = nil) synchronize do |client| client.call([:info, cmd].compact) do |reply| if reply.kind_of?(String) reply = Hash[reply.split("\r\n").map do |line| line.split(":", 2) unless line =~ /^(#|$)/ end.compact] if cmd && cmd.to_s == "commandstats" # Extract nested hashes for INFO COMMANDSTATS reply = Hash[reply.map do |k, v| v = v.split(",").map { |e| e.split("=") } [k[/^cmdstat_(.*)$/, 1], Hash[v]] end] end end reply end end end
# File lib/redis.rb, line 2695 def inspect "#<Redis client v#{Redis::VERSION} for #{id}>" end
Find all keys matching the given pattern.
@param [String] pattern @return [Array<String>]
# File lib/redis.rb, line 512 def keys(pattern = "*") synchronize do |client| client.call([:keys, pattern]) do |reply| if reply.kind_of?(String) reply.split(" ") else reply end end end end
Get the UNIX time stamp of the last successful save to disk.
@return [Fixnum]
# File lib/redis.rb, line 274 def lastsave synchronize do |client| client.call([:lastsave]) end end
Get an element from a list by its index.
@param [String] key @param [Fixnum] index @return [String]
# File lib/redis.rb, line 1214 def lindex(key, index) synchronize do |client| client.call([:lindex, key, index]) end end
Insert an element before or after another element in a list.
@param [String] key @param [String, Symbol] where `BEFORE` or `AFTER` @param [String] pivot reference element @param [String] value @return [Fixnum] length of the list after the insert operation, or `-1`
when the element `pivot` was not found
# File lib/redis.rb, line 1228 def linsert(key, where, pivot, value) synchronize do |client| client.call([:linsert, key, where, pivot, value]) end end
Get the length of a list.
@param [String] key @return [Fixnum]
# File lib/redis.rb, line 1035 def llen(key) synchronize do |client| client.call([:llen, key]) end end
Remove and get the first element in a list.
@param [String] key @return [String]
# File lib/redis.rb, line 1089 def lpop(key) synchronize do |client| client.call([:lpop, key]) end end
Prepend one or more values to a list, creating the list if it doesn't exist
@param [String] key @param [String, Array] value string value, or array of string values to push @return [Fixnum] the length of the list after the push operation
# File lib/redis.rb, line 1046 def lpush(key, value) synchronize do |client| client.call([:lpush, key, value]) end end
Prepend a value to a list, only if the list exists.
@param [String] key @param [String] value @return [Fixnum] the length of the list after the push operation
# File lib/redis.rb, line 1057 def lpushx(key, value) synchronize do |client| client.call([:lpushx, key, value]) end end
Get a range of elements from a list.
@param [String] key @param [Fixnum] start start index @param [Fixnum] stop stop index @return [Array<String>]
# File lib/redis.rb, line 1240 def lrange(key, start, stop) synchronize do |client| client.call([:lrange, key, start, stop]) end end
Remove elements from a list.
@param [String] key @param [Fixnum] count number of elements to remove. Use a positive
value to remove the first `count` occurrences of `value`. A negative value to remove the last `count` occurrences of `value`. Or zero, to remove all occurrences of `value` from the list.
@param [String] value @return [Fixnum] the number of removed elements
# File lib/redis.rb, line 1255 def lrem(key, count, value) synchronize do |client| client.call([:lrem, key, count, value]) end end
Set the value of an element in a list by its index.
@param [String] key @param [Fixnum] index @param [String] value @return [String] `OK`
# File lib/redis.rb, line 1267 def lset(key, index, value) synchronize do |client| client.call([:lset, key, index, value]) end end
Trim a list to the specified range.
@param [String] key @param [Fixnum] start start index @param [Fixnum] stop stop index @return [String] `OK`
# File lib/redis.rb, line 1279 def ltrim(key, start, stop) synchronize do |client| client.call([:ltrim, key, start, stop]) end end
Get the values of all the given hash fields.
@example
redis.mapped_hmget("hash", "f1", "f2") # => { "f1" => "v1", "f2" => "v2" }
@param [String] key @param [Array<String>] fields array of fields @return [Hash] a hash mapping the specified fields to their values
@see hmget
# File lib/redis.rb, line 2041 def mapped_hmget(key, *fields) hmget(key, *fields) do |reply| if reply.kind_of?(Array) Hash[fields.zip(reply)] else reply end end end
Set one or more hash values.
@example
redis.mapped_hmset("hash", { "f1" => "v1", "f2" => "v2" }) # => "OK"
@param [String] key @param [Hash] hash a non-empty hash with fields mapping to values @return [String] `“OK”`
@see hmset
# File lib/redis.rb, line 1998 def mapped_hmset(key, hash) hmset(key, hash.to_a.flatten) end
Get the values of all the given keys.
@example
redis.mapped_mget("key1", "key2") # => { "key1" => "v1", "key2" => "v2" }
@param [Array<String>] keys array of keys @return [Hash] a hash mapping the specified keys to their values
@see mget
# File lib/redis.rb, line 894 def mapped_mget(*keys) mget(*keys) do |reply| if reply.kind_of?(Array) Hash[keys.zip(reply)] else reply end end end
Set one or more values.
@example
redis.mapped_mset({ "f1" => "v1", "f2" => "v2" }) # => "OK"
@param [Hash] hash keys mapping to values @return [String] `“OK”`
@see mset
# File lib/redis.rb, line 822 def mapped_mset(hash) mset(hash.to_a.flatten) end
Set one or more values, only if none of the keys exist.
@example
redis.mapped_msetnx({ "key1" => "v1", "key2" => "v2" }) # => true
@param [Hash] hash keys mapping to values @return [Boolean] whether or not all values were set
@see msetnx
# File lib/redis.rb, line 852 def mapped_msetnx(hash) msetnx(hash.to_a.flatten) end
# File lib/redis.rb, line 2713 def method_missing(command, *args) synchronize do |client| client.call([command] + args) end end
Get the values of all the given keys.
@example
redis.mget("key1", "key1") # => ["v1", "v2"]
@param [Array<String>] keys @return [Array<String>] an array of values for the specified keys
@see mapped_mget
# File lib/redis.rb, line 878 def mget(*keys, &blk) synchronize do |client| client.call([:mget] + keys, &blk) end end
Transfer a key from the connected instance to another instance.
@param [String] key @param [Hash] options
- `:host => String`: host of instance to migrate to - `:port => Integer`: port of instance to migrate to - `:db => Integer`: database to migrate to (default: same as source) - `:timeout => Integer`: timeout (default: same as connection timeout)
@return [String] `“OK”`
# File lib/redis.rb, line 477 def migrate(key, options) host = options[:host] || raise(RuntimeError, ":host not specified") port = options[:port] || raise(RuntimeError, ":port not specified") db = (options[:db] || client.db).to_i timeout = (options[:timeout] || client.timeout).to_i synchronize do |client| client.call([:migrate, host, port, key, db, timeout]) end end
Listen for all requests received by the server in real time.
There is no way to interrupt this command.
@yield a block to be called for every line of output @yieldparam [String] line timestamp and command that was executed
# File lib/redis.rb, line 286 def monitor(&block) synchronize do |client| client.call_loop([:monitor], &block) end end
Move a key to another database.
@example Move a key to another database
redis.set "foo", "bar" # => "OK" redis.move "foo", 2 # => true redis.exists "foo" # => false redis.select 2 # => "OK" redis.exists "foo" # => true redis.get "foo" # => "bar"
@param [String] key @param [Fixnum] db @return [Boolean] whether the key was moved or not
# File lib/redis.rb, line 543 def move(key, db) synchronize do |client| client.call([:move, key, db], &Boolify) end end
Set one or more values.
@example
redis.mset("key1", "v1", "key2", "v2") # => "OK"
@param [Array<String>] args array of keys and values @return [String] `“OK”`
@see mapped_mset
# File lib/redis.rb, line 806 def mset(*args) synchronize do |client| client.call([:mset] + args) end end
Set one or more values, only if none of the keys exist.
@example
redis.msetnx("key1", "v1", "key2", "v2") # => true
@param [Array<String>] args array of keys and values @return [Boolean] whether or not all values were set
@see mapped_msetnx
# File lib/redis.rb, line 836 def msetnx(*args) synchronize do |client| client.call([:msetnx] + args, &Boolify) end end
Mark the start of a transaction block.
Passing a block is optional.
@example With a block
redis.multi do |multi| multi.set("key", "value") multi.incr("counter") end # => ["OK", 6]
@example Without a block
redis.multi # => "OK" redis.set("key", "value") # => "QUEUED" redis.incr("counter") # => "QUEUED" redis.exec # => ["OK", 6]
@yield [multi] the commands that are called inside this block are cached
and written to the server upon returning from it
@yieldparam [Redis] multi `self`
@return [String, Array<…>]
- when a block is not given, `OK` - when a block is given, an array with replies
# File lib/redis.rb, line 2295 def multi synchronize do |client| if !block_given? client.call([:multi]) else begin pipeline = Pipeline::Multi.new original, @client = @client, pipeline yield(self) original.call_pipeline(pipeline) ensure @client = original end end end end
# File lib/redis.rb, line 549 def object(*args) synchronize do |client| client.call([:object] + args) end end
Remove the expiration from a key.
@param [String] key @return [Boolean] whether the timeout was removed or not
# File lib/redis.rb, line 361 def persist(key) synchronize do |client| client.call([:persist, key], &Boolify) end end
Set a key's time to live in milliseconds.
@param [String] key @param [Fixnum] milliseconds time to live @return [Boolean] whether the timeout was set or not
# File lib/redis.rb, line 412 def pexpire(key, milliseconds) synchronize do |client| client.call([:pexpire, key, milliseconds], &Boolify) end end
Set the expiration for a key as number of milliseconds from UNIX Epoch.
@param [String] key @param [Fixnum] ms_unix_time expiry time specified as number of milliseconds from UNIX Epoch. @return [Boolean] whether the timeout was set or not
# File lib/redis.rb, line 423 def pexpireat(key, ms_unix_time) synchronize do |client| client.call([:pexpireat, key, ms_unix_time], &Boolify) end end
Add one or more members to a HyperLogLog structure.
@param [String] key @param [String, Array<String>] member one member, or array of members @return [Boolean] true if at least 1 HyperLogLog internal register was altered. false otherwise.
# File lib/redis.rb, line 2633 def pfadd(key, member) synchronize do |client| client.call([:pfadd, key, member], &Boolify) end end
Get the approximate cardinality of members added to HyperLogLog structure.
If called with multiple keys, returns the approximate cardinality of the union of the HyperLogLogs contained in the keys.
@param [String, Array<String>] keys @return [Fixnum]
# File lib/redis.rb, line 2646 def pfcount(*keys) synchronize do |client| client.call([:pfcount] + keys) end end
Merge multiple HyperLogLog values into an unique value that will approximate the cardinality of the union of the observed Sets of the source HyperLogLog structures.
@param [String] dest_key destination key @param [String, Array<String>] source_key source key, or array of keys @return [Boolean]
# File lib/redis.rb, line 2658 def pfmerge(dest_key, *source_key) synchronize do |client| client.call([:pfmerge, dest_key, *source_key], &BoolifySet) end end
Ping the server.
@return [String] `PONG`
# File lib/redis.rb, line 147 def ping synchronize do |client| client.call([:ping]) end end
# File lib/redis.rb, line 2253 def pipelined synchronize do |client| begin original, @client = @client, Pipeline.new yield(self) original.call_pipeline(@client) ensure @client = original end end end
Set the time to live in milliseconds of a key.
@param [String] key @param [Fixnum] ttl @param [String] value @return [String] `“OK”`
# File lib/redis.rb, line 779 def psetex(key, ttl, value) synchronize do |client| client.call([:psetex, key, ttl, value.to_s]) end end
Listen for messages published to channels matching the given patterns.
# File lib/redis.rb, line 2163 def psubscribe(*channels, &block) synchronize do |client| _subscription(:psubscribe, 0, channels, block) end end
Listen for messages published to channels matching the given patterns. Throw a timeout error if there is no messages for a timeout period.
# File lib/redis.rb, line 2170 def psubscribe_with_timeout(timeout, *channels, &block) synchronize do |client| _subscription(:psubscribe_with_timeout, timeout, channels, block) end end
Get the time to live (in milliseconds) for a key.
@param [String] key @return [Fixnum] remaining time to live in milliseconds In Redis 2.6 or older the command returns -1 if the key does not exist or if the key exist but has no associated expire.
Starting with Redis 2.8 the return value in case of error changed:
- The command returns -2 if the key does not exist. - The command returns -1 if the key exists but has no associated expire.
# File lib/redis.rb, line 440 def pttl(key) synchronize do |client| client.call([:pttl, key]) end end
Post a message to a channel.
# File lib/redis.rb, line 2128 def publish(channel, message) synchronize do |client| client.call([:publish, channel, message]) end end
Inspect the state of the Pub/Sub subsystem. Possible subcommands: channels, numsub, numpat.
# File lib/redis.rb, line 2186 def pubsub(subcommand, *args) synchronize do |client| client.call([:pubsub, subcommand] + args) end end
Stop listening for messages posted to channels matching the given patterns.
# File lib/redis.rb, line 2177 def punsubscribe(*channels) synchronize do |client| raise RuntimeError, "Can't unsubscribe if not subscribed." unless subscribed? client.punsubscribe(*channels) end end
Queues a command for pipelining.
Commands in the queue are executed with the #commit method.
See redis.io/topics/pipelining for more details.
# File lib/redis.rb, line 104 def queue(*command) @queue[Thread.current.object_id] << command end
Close the connection.
@return [String] `OK`
# File lib/redis.rb, line 166 def quit synchronize do |client| begin client.call([:quit]) rescue ConnectionError ensure client.disconnect end end end
Return a random key from the keyspace.
@return [String]
# File lib/redis.rb, line 558 def randomkey synchronize do |client| client.call([:randomkey]) end end
Rename a key. If the new key already exists it is overwritten.
@param [String] old_name @param [String] new_name @return [String] `OK`
# File lib/redis.rb, line 569 def rename(old_name, new_name) synchronize do |client| client.call([:rename, old_name, new_name]) end end
Rename a key, only if the new key does not exist.
@param [String] old_name @param [String] new_name @return [Boolean] whether the key was renamed or not
# File lib/redis.rb, line 580 def renamenx(old_name, new_name) synchronize do |client| client.call([:renamenx, old_name, new_name], &Boolify) end end
Create a key using the serialized value, previously obtained using DUMP.
@param [String] key @param [String] ttl @param [String] serialized_value @return [String] `“OK”`
# File lib/redis.rb, line 462 def restore(key, ttl, serialized_value) synchronize do |client| client.call([:restore, key, ttl, serialized_value]) end end
Remove and get the last element in a list.
@param [String] key @return [String]
# File lib/redis.rb, line 1099 def rpop(key) synchronize do |client| client.call([:rpop, key]) end end
Remove the last element in a list, append it to another list and return it.
@param [String] source source key @param [String] destination destination key @return [nil, String] the element, or nil when the source key does not exist
# File lib/redis.rb, line 1110 def rpoplpush(source, destination) synchronize do |client| client.call([:rpoplpush, source, destination]) end end
Append one or more values to a list, creating the list if it doesn't exist
@param [String] key @param [String] value @return [Fixnum] the length of the list after the push operation
# File lib/redis.rb, line 1068 def rpush(key, value) synchronize do |client| client.call([:rpush, key, value]) end end
Append a value to a list, only if the list exists.
@param [String] key @param [String] value @return [Fixnum] the length of the list after the push operation
# File lib/redis.rb, line 1079 def rpushx(key, value) synchronize do |client| client.call([:rpushx, key, value]) end end
Add one or more members to a set.
@param [String] key @param [String, Array<String>] member one member, or array of members @return [Boolean, Fixnum] `Boolean` when a single member is specified,
holding whether or not adding the member succeeded, or `Fixnum` when an array of members is specified, holding the number of members that were successfully added
# File lib/redis.rb, line 1303 def sadd(key, member) synchronize do |client| client.call([:sadd, key, member]) do |reply| if member.is_a? Array # Variadic: return integer reply else # Single argument: return boolean Boolify.call(reply) end end end end
Synchronously save the dataset to disk.
@return [String]
# File lib/redis.rb, line 295 def save synchronize do |client| client.call([:save]) end end
Scan the keyspace
@example Retrieve the first batch of keys
redis.scan(0) # => ["4", ["key:21", "key:47", "key:42"]]
@example Retrieve a batch of keys matching a pattern
redis.scan(4, :match => "key:1?") # => ["92", ["key:13", "key:18"]]
@param [String, Integer] cursor the cursor of the iteration @param [Hash] options
- `:match => String`: only return keys matching the pattern - `:count => Integer`: return count keys at most per iteration
@return [String, Array<String>] the next cursor and all found keys
# File lib/redis.rb, line 2486 def scan(cursor, options={}) _scan(:scan, cursor, [], options) end
Scan the keyspace
@example Retrieve all of the keys (with possible duplicates)
redis.scan_each.to_a # => ["key:21", "key:47", "key:42"]
@example Execute block for each key matching a pattern
redis.scan_each(:match => "key:1?") {|key| puts key} # => key:13 # => key:18
@param [Hash] options
- `:match => String`: only return keys matching the pattern - `:count => Integer`: return count keys at most per iteration
@return [Enumerator] an enumerator for all found keys
# File lib/redis.rb, line 2505 def scan_each(options={}, &block) return to_enum(:scan_each, options) unless block_given? cursor = 0 loop do cursor, keys = scan(cursor, options) keys.each(&block) break if cursor == "0" end end
Get the number of members in a set.
@param [String] key @return [Fixnum]
# File lib/redis.rb, line 1289 def scard(key) synchronize do |client| client.call([:scard, key]) end end
Control remote script registry.
@example Load a script
sha = redis.script(:load, "return 1") # => <sha of this script>
@example Check if a script exists
redis.script(:exists, sha) # => true
@example Check if multiple scripts exist
redis.script(:exists, [sha, other_sha]) # => [true, false]
@example Flush the script registry
redis.script(:flush) # => "OK"
@example Kill a running script
redis.script(:kill) # => "OK"
@param [String] subcommand e.g. `exists`, `flush`, `load`, `kill` @param [Array<String>] args depends on subcommand @return [String, Boolean, Array<Boolean>, …] depends on subcommand
# File lib/redis.rb, line 2366 def script(subcommand, *args) subcommand = subcommand.to_s.downcase if subcommand == "exists" synchronize do |client| arg = args.first client.call([:script, :exists, arg]) do |reply| reply = reply.map { |r| Boolify.call(r) } if arg.is_a?(Array) reply else reply.first end end end else synchronize do |client| client.call([:script, subcommand] + args) end end end
Subtract multiple sets.
@param [String, Array<String>] keys keys pointing to sets to subtract @return [Array<String>] members in the difference
# File lib/redis.rb, line 1406 def sdiff(*keys) synchronize do |client| client.call([:sdiff] + keys) end end
Subtract multiple sets and store the resulting set in a key.
@param [String] destination destination key @param [String, Array<String>] keys keys pointing to sets to subtract @return [Fixnum] number of elements in the resulting set
# File lib/redis.rb, line 1417 def sdiffstore(destination, *keys) synchronize do |client| client.call([:sdiffstore, destination] + keys) end end
Change the selected database for the current connection.
@param [Fixnum] db zero-based index of the DB to use (0 to 15) @return [String] `OK`
# File lib/redis.rb, line 137 def select(db) synchronize do |client| client.db = db client.call([:select, db]) end end
Interact with the sentinel command (masters, master, slaves, failover)
@param [String] subcommand e.g. `masters`, `master`, `slaves` @param [Array<String>] args depends on subcommand @return [Array<String>, Hash<String, String>, String] depends on subcommand
# File lib/redis.rb, line 2669 def sentinel(subcommand, *args) subcommand = subcommand.to_s.downcase synchronize do |client| client.call([:sentinel, subcommand] + args) do |reply| case subcommand when "get-master-addr-by-name" reply else if reply.kind_of?(Array) if reply[0].kind_of?(Array) reply.map(&Hashify) else Hashify.call(reply) end else reply end end end end end
Set the string value of a key.
@param [String] key @param [String] value @param [Hash] options
- `:ex => Fixnum`: Set the specified expire time, in seconds. - `:px => Fixnum`: Set the specified expire time, in milliseconds. - `:nx => true`: Only set the key if it does not already exist. - `:xx => true`: Only set the key if it already exist.
@return [String, Boolean] `“OK”` or true, false if `:nx => true` or `:xx => true`
# File lib/redis.rb, line 735 def set(key, value, options = {}) args = [] ex = options[:ex] args.concat(["EX", ex]) if ex px = options[:px] args.concat(["PX", px]) if px nx = options[:nx] args.concat(["NX"]) if nx xx = options[:xx] args.concat(["XX"]) if xx synchronize do |client| if nx || xx client.call([:set, key, value.to_s] + args, &BoolifySet) else client.call([:set, key, value.to_s] + args) end end end
Sets or clears the bit at offset in the string value stored at key.
@param [String] key @param [Fixnum] offset bit offset @param [Fixnum] value bit value `0` or `1` @return [Fixnum] the original bit value stored at `offset`
# File lib/redis.rb, line 935 def setbit(key, offset, value) synchronize do |client| client.call([:setbit, key, offset, value]) end end
Set the time to live in seconds of a key.
@param [String] key @param [Fixnum] ttl @param [String] value @return [String] `“OK”`
# File lib/redis.rb, line 767 def setex(key, ttl, value) synchronize do |client| client.call([:setex, key, ttl, value.to_s]) end end
Set the value of a key, only if the key does not exist.
@param [String] key @param [String] value @return [Boolean] whether the key was set or not
# File lib/redis.rb, line 790 def setnx(key, value) synchronize do |client| client.call([:setnx, key, value.to_s], &Boolify) end end
Overwrite part of a string at key starting at the specified offset.
@param [String] key @param [Fixnum] offset byte offset @param [String] value @return [Fixnum] length of the string after it was modified
# File lib/redis.rb, line 910 def setrange(key, offset, value) synchronize do |client| client.call([:setrange, key, offset, value.to_s]) end end
Synchronously save the dataset to disk and then shut down the server.
# File lib/redis.rb, line 302 def shutdown synchronize do |client| client.with_reconnect(false) do begin client.call([:shutdown]) rescue ConnectionError # This means Redis has probably exited. nil end end end end
Intersect multiple sets.
@param [String, Array<String>] keys keys pointing to sets to intersect @return [Array<String>] members in the intersection
# File lib/redis.rb, line 1427 def sinter(*keys) synchronize do |client| client.call([:sinter] + keys) end end
Intersect multiple sets and store the resulting set in a key.
@param [String] destination destination key @param [String, Array<String>] keys keys pointing to sets to intersect @return [Fixnum] number of elements in the resulting set
# File lib/redis.rb, line 1438 def sinterstore(destination, *keys) synchronize do |client| client.call([:sinterstore, destination] + keys) end end
Determine if a given value is a member of a set.
@param [String] key @param [String] member @return [Boolean]
# File lib/redis.rb, line 1386 def sismember(key, member) synchronize do |client| client.call([:sismember, key, member], &Boolify) end end
Make the server a slave of another instance, or promote it as master.
# File lib/redis.rb, line 316 def slaveof(host, port) synchronize do |client| client.call([:slaveof, host, port]) end end
Interact with the slowlog (get, len, reset)
@param [String] subcommand e.g. `get`, `len`, `reset` @param [Fixnum] length maximum number of entries to return @return [Array<String>, Fixnum, String] depends on subcommand
# File lib/redis.rb, line 327 def slowlog(subcommand, length=nil) synchronize do |client| args = [:slowlog, subcommand] args << length if length client.call args end end
Get all the members in a set.
@param [String] key @return [Array<String>]
# File lib/redis.rb, line 1396 def smembers(key) synchronize do |client| client.call([:smembers, key]) end end
Move a member from one set to another.
@param [String] source source key @param [String] destination destination key @param [String] member member to move from `source` to `destination` @return [Boolean]
# File lib/redis.rb, line 1375 def smove(source, destination, member) synchronize do |client| client.call([:smove, source, destination, member], &Boolify) end end
Sort the elements in a list, set or sorted set.
@example Retrieve the first 2 elements from an alphabetically sorted “list”
redis.sort("list", :order => "alpha", :limit => [0, 2]) # => ["a", "b"]
@example Store an alphabetically descending list in “target”
redis.sort("list", :order => "desc alpha", :store => "target") # => 26
@param [String] key @param [Hash] options
- `:by => String`: use external key to sort elements by - `:limit => [offset, count]`: skip `offset` elements, return a maximum of `count` elements - `:get => [String, Array<String>]`: single key or array of keys to retrieve per element in the result - `:order => String`: combination of `ASC`, `DESC` and optionally `ALPHA` - `:store => String`: key to store the result at
@return [Array<String>, Array<Array<String>>, Fixnum]
- when `:get` is not specified, or holds a single element, an array of elements - when `:get` is specified, and holds more than one element, an array of elements where every element is an array with the result for every element specified in `:get` - when `:store` is specified, the number of elements in the stored result
# File lib/redis.rb, line 611 def sort(key, options = {}) args = [] by = options[:by] args.concat(["BY", by]) if by limit = options[:limit] args.concat(["LIMIT"] + limit) if limit get = Array(options[:get]) args.concat(["GET"].product(get).flatten) unless get.empty? order = options[:order] args.concat(order.split(" ")) if order store = options[:store] args.concat(["STORE", store]) if store synchronize do |client| client.call([:sort, key] + args) do |reply| if get.size > 1 && !store if reply reply.each_slice(get.size).to_a end else reply end end end end
Remove and return one or more random member from a set.
@param [String] key @return [String] @param [Fixnum] count
# File lib/redis.rb, line 1344 def spop(key, count = nil) synchronize do |client| if count.nil? client.call([:spop, key]) else client.call([:spop, key, count]) end end end
Get one or more random members from a set.
@param [String] key @param [Fixnum] count @return [String]
# File lib/redis.rb, line 1359 def srandmember(key, count = nil) synchronize do |client| if count.nil? client.call([:srandmember, key]) else client.call([:srandmember, key, count]) end end end
Remove one or more members from a set.
@param [String] key @param [String, Array<String>] member one member, or array of members @return [Boolean, Fixnum] `Boolean` when a single member is specified,
holding whether or not removing the member succeeded, or `Fixnum` when an array of members is specified, holding the number of members that were successfully removed
# File lib/redis.rb, line 1325 def srem(key, member) synchronize do |client| client.call([:srem, key, member]) do |reply| if member.is_a? Array # Variadic: return integer reply else # Single argument: return boolean Boolify.call(reply) end end end end
Scan a set
@example Retrieve the first batch of keys in a set
redis.sscan("set", 0)
@param [String, Integer] cursor the cursor of the iteration @param [Hash] options
- `:match => String`: only return keys matching the pattern - `:count => Integer`: return count keys at most per iteration
@return [String, Array<String>] the next cursor and all found members
# File lib/redis.rb, line 2603 def sscan(key, cursor, options={}) _scan(:sscan, cursor, [key], options) end
Scan a set
@example Retrieve all of the keys in a set
redis.sscan_each("set").to_a # => ["key1", "key2", "key3"]
@param [Hash] options
- `:match => String`: only return keys matching the pattern - `:count => Integer`: return count keys at most per iteration
@return [Enumerator] an enumerator for all keys in the set
# File lib/redis.rb, line 2618 def sscan_each(key, options={}, &block) return to_enum(:sscan_each, key, options) unless block_given? cursor = 0 loop do cursor, keys = sscan(key, cursor, options) keys.each(&block) break if cursor == "0" end end
Get the length of the value stored in a key.
@param [String] key @return [Fixnum] the length of the value stored in the key, or 0
if the key does not exist
# File lib/redis.rb, line 1025 def strlen(key) synchronize do |client| client.call([:strlen, key]) end end
Listen for messages published to the given channels.
# File lib/redis.rb, line 2141 def subscribe(*channels, &block) synchronize do |client| _subscription(:subscribe, 0, channels, block) end end
Listen for messages published to the given channels. Throw a timeout error if there is no messages for a timeout period.
# File lib/redis.rb, line 2148 def subscribe_with_timeout(timeout, *channels, &block) synchronize do |client| _subscription(:subscribe_with_timeout, timeout, channels, block) end end
# File lib/redis.rb, line 2134 def subscribed? synchronize do |client| client.kind_of? SubscribedClient end end
Add multiple sets.
@param [String, Array<String>] keys keys pointing to sets to unify @return [Array<String>] members in the union
# File lib/redis.rb, line 1448 def sunion(*keys) synchronize do |client| client.call([:sunion] + keys) end end
Add multiple sets and store the resulting set in a key.
@param [String] destination destination key @param [String, Array<String>] keys keys pointing to sets to unify @return [Fixnum] number of elements in the resulting set
# File lib/redis.rb, line 1459 def sunionstore(destination, *keys) synchronize do |client| client.call([:sunionstore, destination] + keys) end end
Internal command used for replication.
# File lib/redis.rb, line 336 def sync synchronize do |client| client.call([:sync]) end end
# File lib/redis.rb, line 57 def synchronize mon_synchronize { yield(@client) } end
Return the server time.
@example
r.time # => [ 1333093196, 606806 ]
@return [Array<Fixnum>] tuple of seconds since UNIX epoch and
microseconds in the current second
# File lib/redis.rb, line 349 def time synchronize do |client| client.call([:time]) do |reply| reply.map(&:to_i) if reply end end end
Get the time to live (in seconds) for a key.
@param [String] key @return [Fixnum] remaining time to live in seconds.
In Redis 2.6 or older the command returns -1 if the key does not exist or if the key exist but has no associated expire.
Starting with Redis 2.8 the return value in case of error changed:
- The command returns -2 if the key does not exist. - The command returns -1 if the key exists but has no associated expire.
# File lib/redis.rb, line 401 def ttl(key) synchronize do |client| client.call([:ttl, key]) end end
Determine the type stored at key.
@param [String] key @return [String] `string`, `list`, `set`, `zset`, `hash` or `none`
# File lib/redis.rb, line 646 def type(key) synchronize do |client| client.call([:type, key]) end end
Stop listening for messages posted to the given channels.
# File lib/redis.rb, line 2155 def unsubscribe(*channels) synchronize do |client| raise RuntimeError, "Can't unsubscribe if not subscribed." unless subscribed? client.unsubscribe(*channels) end end
Watch the given keys to determine execution of the MULTI/EXEC block.
Using a block is optional, but is necessary for thread-safety.
An `#unwatch` is automatically issued if an exception is raised within the block that is a subclass of StandardError and is not a ConnectionError.
@example With a block
redis.watch("key") do if redis.get("key") == "some value" redis.multi do |multi| multi.set("key", "other value") multi.incr("counter") end else redis.unwatch end end # => ["OK", 6]
@example Without a block
redis.watch("key") # => "OK"
@param [String, Array<String>] keys one or more keys to watch @return [Object] if using a block, returns the return value of the block @return [String] if not using a block, returns `OK`
# File lib/redis.rb, line 2222 def watch(*keys) synchronize do |client| res = client.call([:watch] + keys) if block_given? begin yield(self) rescue ConnectionError raise rescue StandardError unwatch raise end else res end end end
Run code with the client reconnecting
# File lib/redis.rb, line 62 def with_reconnect(val=true, &blk) synchronize do |client| client.with_reconnect(val, &blk) end end
Run code without the client reconnecting
# File lib/redis.rb, line 69 def without_reconnect(&blk) with_reconnect(false, &blk) end
Add one or more members to a sorted set, or update the score for members that already exist.
@example Add a single `[score, member]` pair to a sorted set
redis.zadd("zset", 32.0, "member")
@example Add an array of `[score, member]` pairs to a sorted set
redis.zadd("zset", [[32.0, "a"], [64.0, "b"]])
@param [String] key @param [[Float, String], Array<[Float, String]>] args
- a single `[score, member]` pair - an array of `[score, member]` pairs
@param [Hash] options
- `:xx => true`: Only update elements that already exist (never add elements) - `:nx => true`: Don't update already existing elements (always add new elements) - `:ch => true`: Modify the return value from the number of new elements added, to the total number of elements changed (CH is an abbreviation of changed); changed elements are new elements added and elements already existing for which the score was updated - `:incr => true`: When this option is specified ZADD acts like ZINCRBY; only one score-element pair can be specified in this mode
@return [Boolean, Fixnum, Float]
- `Boolean` when a single pair is specified, holding whether or not it was **added** to the sorted set. - `Fixnum` when an array of pairs is specified, holding the number of pairs that were **added** to the sorted set. - `Float` when option :incr is specified, holding the score of the member after incrementing it.
# File lib/redis.rb, line 1510 def zadd(key, *args) #, options zadd_options = [] if args.last.is_a?(Hash) options = args.pop nx = options[:nx] zadd_options << "NX" if nx xx = options[:xx] zadd_options << "XX" if xx ch = options[:ch] zadd_options << "CH" if ch incr = options[:incr] zadd_options << "INCR" if incr end synchronize do |client| if args.size == 1 && args[0].is_a?(Array) # Variadic: return float if INCR, integer if !INCR client.call([:zadd, key] + zadd_options + args[0], &(incr ? Floatify : nil)) elsif args.size == 2 # Single pair: return float if INCR, boolean if !INCR client.call([:zadd, key] + zadd_options + args, &(incr ? Floatify : Boolify)) else raise ArgumentError, "wrong number of arguments" end end end
Get the number of members in a sorted set.
@example
redis.zcard("zset") # => 4
@param [String] key @return [Fixnum]
# File lib/redis.rb, line 1473 def zcard(key) synchronize do |client| client.call([:zcard, key]) end end
Count the members in a sorted set with scores within the given values.
@example Count members with score `>= 5` and `< 100`
redis.zcount("zset", "5", "(100") # => 2
@example Count members with scores `> 5`
redis.zcount("zset", "(5", "+inf") # => 2
@param [String] key @param [String] min
- inclusive minimum score is specified verbatim - exclusive minimum score is specified by prefixing `(`
@param [String] max
- inclusive maximum score is specified verbatim - exclusive maximum score is specified by prefixing `(`
@return [Fixnum] number of members in within the specified range
# File lib/redis.rb, line 1875 def zcount(key, min, max) synchronize do |client| client.call([:zcount, key, min, max]) end end
Increment the score of a member in a sorted set.
@example
redis.zincrby("zset", 32.0, "a") # => 64.0
@param [String] key @param [Float] increment @param [String] member @return [Float] score of the member after incrementing it
# File lib/redis.rb, line 1551 def zincrby(key, increment, member) synchronize do |client| client.call([:zincrby, key, increment, member], &Floatify) end end
Intersect multiple sorted sets and store the resulting sorted set in a new key.
@example Compute the intersection of `2*zsetA` with `1*zsetB`, summing their scores
redis.zinterstore("zsetC", ["zsetA", "zsetB"], :weights => [2.0, 1.0], :aggregate => "sum") # => 4
@param [String] destination destination key @param [Array<String>] keys source keys @param [Hash] options
- `:weights => [Float, Float, ...]`: weights to associate with source sorted sets - `:aggregate => String`: aggregate function to use (sum, min, max, ...)
@return [Fixnum] number of elements in the resulting sorted set
# File lib/redis.rb, line 1895 def zinterstore(destination, keys, options = {}) args = [] weights = options[:weights] args.concat(["WEIGHTS"] + weights) if weights aggregate = options[:aggregate] args.concat(["AGGREGATE", aggregate]) if aggregate synchronize do |client| client.call([:zinterstore, destination, keys.size] + keys + args) end end
Return a range of members in a sorted set, by index.
@example Retrieve all members from a sorted set
redis.zrange("zset", 0, -1) # => ["a", "b"]
@example Retrieve all members and their scores from a sorted set
redis.zrange("zset", 0, -1, :with_scores => true) # => [["a", 32.0], ["b", 64.0]]
@param [String] key @param [Fixnum] start start index @param [Fixnum] stop stop index @param [Hash] options
- `:with_scores => true`: include scores in output
@return [Array<String>, Array<[String, Float]>]
- when `:with_scores` is not specified, an array of members - when `:with_scores` is specified, an array with `[member, score]` pairs
# File lib/redis.rb, line 1621 def zrange(key, start, stop, options = {}) args = [] with_scores = options[:with_scores] || options[:withscores] if with_scores args << "WITHSCORES" block = FloatifyPairs end synchronize do |client| client.call([:zrange, key, start, stop] + args, &block) end end
Return a range of members with the same score in a sorted set, by lexicographical ordering
@example Retrieve members matching a
redis.zrangebylex("zset", "[a", "[a\xff") # => ["aaren", "aarika", "abagael", "abby"]
@example Retrieve the first 2 members matching a
redis.zrangebylex("zset", "[a", "[a\xff", :limit => [0, 2]) # => ["aaren", "aarika"]
@param [String] key @param [String] min
- inclusive minimum is specified by prefixing `(` - exclusive minimum is specified by prefixing `[`
@param [String] max
- inclusive maximum is specified by prefixing `(` - exclusive maximum is specified by prefixing `[`
@param [Hash] options
- `:limit => [offset, count]`: skip `offset` members, return a maximum of `count` members
@return [Array<String>, Array<[String, Float]>]
# File lib/redis.rb, line 1725 def zrangebylex(key, min, max, options = {}) args = [] limit = options[:limit] args.concat(["LIMIT"] + limit) if limit synchronize do |client| client.call([:zrangebylex, key, min, max] + args) end end
Return a range of members in a sorted set, by score.
@example Retrieve members with score `>= 5` and `< 100`
redis.zrangebyscore("zset", "5", "(100") # => ["a", "b"]
@example Retrieve the first 2 members with score `>= 0`
redis.zrangebyscore("zset", "0", "+inf", :limit => [0, 2]) # => ["a", "b"]
@example Retrieve members and their scores with scores `> 5`
redis.zrangebyscore("zset", "(5", "+inf", :with_scores => true) # => [["a", 32.0], ["b", 64.0]]
@param [String] key @param [String] min
- inclusive minimum score is specified verbatim - exclusive minimum score is specified by prefixing `(`
@param [String] max
- inclusive maximum score is specified verbatim - exclusive maximum score is specified by prefixing `(`
@param [Hash] options
- `:with_scores => true`: include scores in output - `:limit => [offset, count]`: skip `offset` members, return a maximum of `count` members
@return [Array<String>, Array<[String, Float]>]
- when `:with_scores` is not specified, an array of members - when `:with_scores` is specified, an array with `[member, score]` pairs
# File lib/redis.rb, line 1785 def zrangebyscore(key, min, max, options = {}) args = [] with_scores = options[:with_scores] || options[:withscores] if with_scores args << "WITHSCORES" block = FloatifyPairs end limit = options[:limit] args.concat(["LIMIT"] + limit) if limit synchronize do |client| client.call([:zrangebyscore, key, min, max] + args, &block) end end
Determine the index of a member in a sorted set.
@param [String] key @param [String] member @return [Fixnum]
# File lib/redis.rb, line 1667 def zrank(key, member) synchronize do |client| client.call([:zrank, key, member]) end end
Remove one or more members from a sorted set.
@example Remove a single member from a sorted set
redis.zrem("zset", "a")
@example Remove an array of members from a sorted set
redis.zrem("zset", ["a", "b"])
@param [String] key @param [String, Array<String>] member
- a single member - an array of members
@return [Boolean, Fixnum]
- `Boolean` when a single member is specified, holding whether or not it was removed from the sorted set - `Fixnum` when an array of pairs is specified, holding the number of members that were removed to the sorted set
# File lib/redis.rb, line 1574 def zrem(key, member) synchronize do |client| client.call([:zrem, key, member]) do |reply| if member.is_a? Array # Variadic: return integer reply else # Single argument: return boolean Boolify.call(reply) end end end end
Remove all members in a sorted set within the given indexes.
@example Remove first 5 members
redis.zremrangebyrank("zset", 0, 4) # => 5
@example Remove last 5 members
redis.zremrangebyrank("zset", -5, -1) # => 5
@param [String] key @param [Fixnum] start start index @param [Fixnum] stop stop index @return [Fixnum] number of members that were removed
# File lib/redis.rb, line 1698 def zremrangebyrank(key, start, stop) synchronize do |client| client.call([:zremrangebyrank, key, start, stop]) end end
Remove all members in a sorted set within the given scores.
@example Remove members with score `>= 5` and `< 100`
redis.zremrangebyscore("zset", "5", "(100") # => 2
@example Remove members with scores `> 5`
redis.zremrangebyscore("zset", "(5", "+inf") # => 2
@param [String] key @param [String] min
- inclusive minimum score is specified verbatim - exclusive minimum score is specified by prefixing `(`
@param [String] max
- inclusive maximum score is specified verbatim - exclusive maximum score is specified by prefixing `(`
@return [Fixnum] number of members that were removed
# File lib/redis.rb, line 1852 def zremrangebyscore(key, min, max) synchronize do |client| client.call([:zremrangebyscore, key, min, max]) end end
Return a range of members in a sorted set, by index, with scores ordered from high to low.
@example Retrieve all members from a sorted set
redis.zrevrange("zset", 0, -1) # => ["b", "a"]
@example Retrieve all members and their scores from a sorted set
redis.zrevrange("zset", 0, -1, :with_scores => true) # => [["b", 64.0], ["a", 32.0]]
@see zrange
# File lib/redis.rb, line 1647 def zrevrange(key, start, stop, options = {}) args = [] with_scores = options[:with_scores] || options[:withscores] if with_scores args << "WITHSCORES" block = FloatifyPairs end synchronize do |client| client.call([:zrevrange, key, start, stop] + args, &block) end end
Return a range of members with the same score in a sorted set, by reversed lexicographical ordering. Apart from the reversed ordering, zrevrangebylex is similar to zrangebylex.
@example Retrieve members matching a
redis.zrevrangebylex("zset", "[a", "[a\xff") # => ["abbygail", "abby", "abagael", "aaren"]
@example Retrieve the last 2 members matching a
redis.zrevrangebylex("zset", "[a", "[a\xff", :limit => [0, 2]) # => ["abbygail", "abby"]
@see zrangebylex
# File lib/redis.rb, line 1747 def zrevrangebylex(key, max, min, options = {}) args = [] limit = options[:limit] args.concat(["LIMIT"] + limit) if limit synchronize do |client| client.call([:zrevrangebylex, key, max, min] + args) end end
Return a range of members in a sorted set, by score, with scores ordered from high to low.
@example Retrieve members with score `< 100` and `>= 5`
redis.zrevrangebyscore("zset", "(100", "5") # => ["b", "a"]
@example Retrieve the first 2 members with score `<= 0`
redis.zrevrangebyscore("zset", "0", "-inf", :limit => [0, 2]) # => ["b", "a"]
@example Retrieve members and their scores with scores `> 5`
redis.zrevrangebyscore("zset", "+inf", "(5", :with_scores => true) # => [["b", 64.0], ["a", 32.0]]
@see zrangebyscore
# File lib/redis.rb, line 1817 def zrevrangebyscore(key, max, min, options = {}) args = [] with_scores = options[:with_scores] || options[:withscores] if with_scores args << ["WITHSCORES"] block = FloatifyPairs end limit = options[:limit] args.concat(["LIMIT"] + limit) if limit synchronize do |client| client.call([:zrevrangebyscore, key, max, min] + args, &block) end end
Determine the index of a member in a sorted set, with scores ordered from high to low.
@param [String] key @param [String] member @return [Fixnum]
# File lib/redis.rb, line 1679 def zrevrank(key, member) synchronize do |client| client.call([:zrevrank, key, member]) end end
Scan a sorted set
@example Retrieve the first batch of key/value pairs in a hash
redis.zscan("zset", 0)
@param [String, Integer] cursor the cursor of the iteration @param [Hash] options
- `:match => String`: only return keys matching the pattern - `:count => Integer`: return count keys at most per iteration
@return [String, Array<[String, Float]>] the next cursor and all found
members and scores
# File lib/redis.rb, line 2565 def zscan(key, cursor, options={}) _scan(:zscan, cursor, [key], options) do |reply| [reply[0], FloatifyPairs.call(reply[1])] end end
Scan a sorted set
@example Retrieve all of the members/scores in a sorted set
redis.zscan_each("zset").to_a # => [["key70", "70"], ["key80", "80"]]
@param [Hash] options
- `:match => String`: only return keys matching the pattern - `:count => Integer`: return count keys at most per iteration
@return [Enumerator] an enumerator for all found scores and members
# File lib/redis.rb, line 2582 def zscan_each(key, options={}, &block) return to_enum(:zscan_each, key, options) unless block_given? cursor = 0 loop do cursor, values = zscan(key, cursor, options) values.each(&block) break if cursor == "0" end end
Get the score associated with the given member in a sorted set.
@example Get the score for member “a”
redis.zscore("zset", "a") # => 32.0
@param [String] key @param [String] member @return [Float] score of the member
# File lib/redis.rb, line 1597 def zscore(key, member) synchronize do |client| client.call([:zscore, key, member], &Floatify) end end
Add multiple sorted sets and store the resulting sorted set in a new key.
@example Compute the union of `2*zsetA` with `1*zsetB`, summing their scores
redis.zunionstore("zsetC", ["zsetA", "zsetB"], :weights => [2.0, 1.0], :aggregate => "sum") # => 8
@param [String] destination destination key @param [Array<String>] keys source keys @param [Hash] options
- `:weights => [Float, Float, ...]`: weights to associate with source sorted sets - `:aggregate => String`: aggregate function to use (sum, min, max, ...)
@return [Fixnum] number of elements in the resulting sorted set
# File lib/redis.rb, line 1922 def zunionstore(destination, keys, options = {}) args = [] weights = options[:weights] args.concat(["WEIGHTS"] + weights) if weights aggregate = options[:aggregate] args.concat(["AGGREGATE", aggregate]) if aggregate synchronize do |client| client.call([:zunionstore, destination, keys.size] + keys + args) end end
Private Instance Methods
# File lib/redis.rb, line 2767 def _subscription(method, timeout, channels, block) return @client.call([method] + channels) if subscribed? begin original, @client = @client, SubscribedClient.new(@client) if timeout > 0 @client.send(method, timeout, *channels, &block) else @client.send(method, *channels, &block) end ensure @client = original end end