Class: Redis::SortedSet

Inherits:
BaseObject show all
Includes:
Helpers::CoreCommands, Helpers::Serialize
Defined in:
lib/redis/sorted_set.rb

Overview

Class representing a sorted set.

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Helpers::Serialize

#from_redis, #to_redis

Methods included from Helpers::CoreCommands

#exists?, #expire, #expireat, #move, #persist, #rename, #renamenx, #sort, #ttl, #type

Methods inherited from BaseObject

#initialize, #redis

Constructor Details

This class inherits a constructor from Redis::BaseObject

Instance Attribute Details

#key ⇒ Object (readonly)

Returns the value of attribute key.



15
16
17
 
# File 'lib/redis/sorted_set.rb', line 15

def key
  @key
end

#options ⇒ Object (readonly)

Returns the value of attribute options.



15
16
17
 
# File 'lib/redis/sorted_set.rb', line 15

def options
  @options
end

Instance Method Details

#==(x) ⇒ Object 



252
253
254
 
# File 'lib/redis/sorted_set.rb', line 252

def ==(x)
  members == x
end

#[](index, length = nil) ⇒ Object Also known as: slice

Same functionality as Ruby arrays. If a single number is given, return just the element at that index using Redis: ZRANGE. Otherwise, return a range of values using Redis: ZRANGE.



34
35
36
37
38
39
40
41
42
43
44
45
46
 
# File 'lib/redis/sorted_set.rb', line 34

def [](index, length=nil)
  if index.is_a? Range
    range(index.first, index.last)
  elsif length
    case length <=> 0
    when 1  then range(index, index + length - 1)
    when 0  then []
    when -1 then nil  # Ruby does this (a bit weird)
    end
  else
    result = score(index) || 0 # handles a nil score
  end
end

#[]=(member, score) ⇒ Object

How to add values using a sorted set. The key is the member, eg, “Peter”, and the value is the score, eg, 163. So:

num_posts['Peter'] = 163



20
21
22
 
# File 'lib/redis/sorted_set.rb', line 20

def []=(member, score)
  add(member, score)
end

#add(member, score) ⇒ Object

Add a member and its corresponding value to Redis. Note that the arguments to this are flipped; the member comes first rather than the score, since the member is the unique item (not the score).



27
28
29
 
# File 'lib/redis/sorted_set.rb', line 27

def add(member, score)
  redis.zadd(key, score, to_redis(member))
end

#at(index) ⇒ Object

Return the value at the given index. Can also use familiar list syntax. Redis: ZRANGE



262
263
264
 
# File 'lib/redis/sorted_set.rb', line 262

def at(index)
  range(index, index).first
end

#decrement(member, by = 1) ⇒ Object Also known as: decr, decrby

Convenience to calling increment() with a negative number.



169
170
171
 
# File 'lib/redis/sorted_set.rb', line 169

def decrement(member, by=1)
  redis.zincrby(key, -by, member).to_i
end

#delete(value) ⇒ Object

Delete the value from the set. Redis: ZREM



144
145
146
 
# File 'lib/redis/sorted_set.rb', line 144

def delete(value)
  redis.zrem(key, to_redis(value))
end

#delete_if(&block) ⇒ Object

Delete element if it matches block

Raises:

  • (ArgumentError) 


149
150
151
152
153
154
155
156
157
158
 
# File 'lib/redis/sorted_set.rb', line 149

def delete_if(&block)
  raise ArgumentError, "Missing block to SortedSet#delete_if" unless block_given?
  res = false
  redis.zrange(key, 0, -1).each do |m|
    if block.call(from_redis(m))
      res = redis.zrem(key, m)
    end
  end
  res
end

#difference(*sets) ⇒ Object Also known as: diff, ^, -

Return the difference vs another set. Can pass it either another set object or set name. Also available as ^ or - which is a bit cleaner:

members_difference = set1 ^ set2
members_difference = set1 - set2

If you want to specify multiple sets, you must use difference:

members_difference = set1.difference(set2, set3, set4)
members_difference = set1.diff(set2, set3, set4)

Redis: SDIFF



234
235
236
 
# File 'lib/redis/sorted_set.rb', line 234

def difference(*sets)
  from_redis redis.zdiff(key, *keys_from_objects(sets))
end

#diffstore(name, *sets) ⇒ Object

Calculate the diff and store it in Redis as name. Returns the number of elements in the stored union. Redis: SDIFFSTORE



243
244
245
 
# File 'lib/redis/sorted_set.rb', line 243

def diffstore(name, *sets)
  redis.zdiffstore(name, key, *keys_from_objects(sets))
end

#empty? ⇒ Boolean

Returns true if the set has no members. Redis: SCARD == 0

Returns:

  • (Boolean) 


248
249
250
 
# File 'lib/redis/sorted_set.rb', line 248

def empty?
  length == 0
end

#first ⇒ Object

Return the first element in the list. Redis: ZRANGE(0)



267
268
269
 
# File 'lib/redis/sorted_set.rb', line 267

def first
  at(0)
end

#increment(member, by = 1) ⇒ Object Also known as: incr, incrby

Increment the rank of that member atomically and return the new value. This method is aliased as incr() for brevity. Redis: ZINCRBY



162
163
164
 
# File 'lib/redis/sorted_set.rb', line 162

def increment(member, by=1)
  redis.zincrby(key, by, member).to_i
end

#intersection(*sets) ⇒ Object Also known as: intersect, inter, &

Return the intersection with another set. Can pass it either another set object or set name. Also available as & which is a bit cleaner:

members_in_both = set1 & set2

If you want to specify multiple sets, you must use intersection:

members_in_all = set1.intersection(set2, set3, set4)
members_in_all = set1.inter(set2, set3, set4)  # alias

Redis: SINTER



186
187
188
 
# File 'lib/redis/sorted_set.rb', line 186

def intersection(*sets)
  from_redis redis.zinter(key, *keys_from_objects(sets))
end

#interstore(name, *sets) ⇒ Object

Calculate the intersection and store it in Redis as name. Returns the number of elements in the stored intersection. Redis: SUNIONSTORE



195
196
197
 
# File 'lib/redis/sorted_set.rb', line 195

def interstore(name, *sets)
  redis.zinterstore(name, keys_from_objects([self] + sets))
end

#last ⇒ Object

Return the last element in the list. Redis: ZRANGE(-1)



272
273
274
 
# File 'lib/redis/sorted_set.rb', line 272

def last
  at(-1)
end

#length ⇒ Object Also known as: size

The number of members in the set. Aliased as size. Redis: ZCARD



277
278
279
 
# File 'lib/redis/sorted_set.rb', line 277

def length
  redis.zcard(key)
end

#member?(value) ⇒ Boolean

Return a boolean indicating whether value is a member.

Returns:

  • (Boolean) 


288
289
290
 
# File 'lib/redis/sorted_set.rb', line 288

def member?(value)
  !redis.zscore(key, to_redis(value)).nil?
end

#members(options = {}) ⇒ Object

Return all members of the sorted set with their scores. Extremely CPU-intensive. Better to use a range instead.



80
81
82
83
 
# File 'lib/redis/sorted_set.rb', line 80

def members(options={})
  v = from_redis range(0, -1, options)
  v.nil? ? [] : v
end

#range(start_index, end_index, options = {}) ⇒ Object

Return a range of values from start_index to end_index. Can also use the familiar list Ruby syntax. Redis: ZRANGE



87
88
89
90
91
92
93
 
# File 'lib/redis/sorted_set.rb', line 87

def range(start_index, end_index, options={})
  if options[:withscores] || options[:with_scores]
    from_redis redis.zrange(key, start_index, end_index, :with_scores => true)
  else
    from_redis redis.zrange(key, start_index, end_index)
  end
end

#range_size(min, max) ⇒ Object

The number of members within a range of scores. Redis: ZCOUNT



283
284
285
 
# File 'lib/redis/sorted_set.rb', line 283

def range_size(min, max)
  redis.zcount(key, min, max)
end

#rangebyscore(min, max, options = {}) ⇒ Object

Return the all the elements in the sorted set at key with a score between min and max (including elements with score equal to min or max). Options:

:count, :offset - passed to LIMIT
:withscores     - if true, scores are returned as well

Redis: ZRANGEBYSCORE



109
110
111
112
113
114
115
116
 
# File 'lib/redis/sorted_set.rb', line 109

def rangebyscore(min, max, options={})
  args = {}
  args[:limit] = [options[:offset] || 0, options[:limit] || options[:count]] if
            options[:offset] || options[:limit] || options[:count]
  args[:with_scores] = true if options[:withscores] || options[:with_scores]

  from_redis redis.zrangebyscore(key, min, max, args)
end

#rank(member) ⇒ Object

Return the rank of the member in the sorted set, with scores ordered from low to high. revrank returns the rank with scores ordered from high to low. When the given member does not exist in the sorted set, nil is returned. The returned rank (or index) of the member is 0-based for both commands



62
63
64
65
66
67
68
 
# File 'lib/redis/sorted_set.rb', line 62

def rank(member)
  if n = redis.zrank(key, to_redis(member))
    n.to_i
  else
    nil
  end
end

#remrangebyrank(min, max) ⇒ Object

Remove all elements in the sorted set at key with rank between start and end. Start and end are 0-based with rank 0 being the element with the lowest score. Both start and end can be negative numbers, where they indicate offsets starting at the element with the highest rank. For example: -1 is the element with the highest score, -2 the element with the second highest score and so forth. Redis: ZREMRANGEBYRANK



133
134
135
 
# File 'lib/redis/sorted_set.rb', line 133

def remrangebyrank(min, max)
  redis.zremrangebyrank(key, min, max)
end

#remrangebyscore(min, max) ⇒ Object

Remove all the elements in the sorted set at key with a score between min and max (including elements with score equal to min or max). Redis: ZREMRANGEBYSCORE



139
140
141
 
# File 'lib/redis/sorted_set.rb', line 139

def remrangebyscore(min, max)
  redis.zremrangebyscore(key, min, max)
end

#revrange(start_index, end_index, options = {}) ⇒ Object

Return a range of values from start_index to end_index in reverse order. Redis: ZREVRANGE



96
97
98
99
100
101
102
 
# File 'lib/redis/sorted_set.rb', line 96

def revrange(start_index, end_index, options={})
  if options[:withscores] || options[:with_scores]
    from_redis redis.zrevrange(key, start_index, end_index, :with_scores => true)
  else
    from_redis redis.zrevrange(key, start_index, end_index)
  end
end

#revrangebyscore(min, max, options = {}) ⇒ Object

Forwards compat (not yet implemented in Redis)



119
120
121
122
123
124
125
126
 
# File 'lib/redis/sorted_set.rb', line 119

def revrangebyscore(min, max, options={})
  args = {}
  args[:limit] = [options[:offset] || 0, options[:limit] || options[:count]] if
            options[:offset] || options[:limit] || options[:count]
  args[:with_scores] = true if options[:withscores] || options[:with_scores]

  from_redis redis.zrevrangebyscore(key, min, max, args)
end

#revrank(member) ⇒ Object 



70
71
72
73
74
75
76
 
# File 'lib/redis/sorted_set.rb', line 70

def revrank(member)
  if n = redis.zrevrank(key, to_redis(member))
    n.to_i
  else
    nil
  end
end

#score(member) ⇒ Object

Return the score of the specified element of the sorted set at key. If the specified element does not exist in the sorted set, or the key does not exist at all, nil is returned. Redis: ZSCORE.



52
53
54
55
56
 
# File 'lib/redis/sorted_set.rb', line 52

def score(member)
  result = redis.zscore(key, to_redis(member))

  result.to_f unless result.nil?
end

#to_s ⇒ Object 



256
257
258
 
# File 'lib/redis/sorted_set.rb', line 256

def to_s
  members.join(', ')
end

#union(*sets) ⇒ Object Also known as: |, +

Return the union with another set. Can pass it either another set object or set name. Also available as | and + which are a bit cleaner:

members_in_either = set1 | set2
members_in_either = set1 + set2

If you want to specify multiple sets, you must use union:

members_in_all = set1.union(set2, set3, set4)

Redis: SUNION



210
211
212
 
# File 'lib/redis/sorted_set.rb', line 210

def union(*sets)
  from_redis redis.zunion(key, *keys_from_objects(sets))
end

#unionstore(name, *sets) ⇒ Object

Calculate the union and store it in Redis as name. Returns the number of elements in the stored union. Redis: SUNIONSTORE



218
219
220
 
# File 'lib/redis/sorted_set.rb', line 218

def unionstore(name, *sets)
  redis.zunionstore(name, keys_from_objects([self] + sets))
end