Class: Bucketer::InMemory

Inherits:
Object
  • Object
show all
Defined in:
lib/bucketer/in_memory.rb

Overview

This is a purpose built class for storing arbitrary objects in buckets then calling callbacks when any of those buckets exceed a certain pre-specified size. The interface is intentially evented looking so that it would be possible to later swap out the backing database with a more persistent database (eg. redis). If this interface was using regular returns this would mean clients would need to change later if we decided to use redis.

Constant Summary collapse

BUCKET_THRESHOLD_SIZE_DEFAULT = 
1000
BUCKET_MAX_AGE_DEFAULT = 
3600

Instance Method Summary collapse

Constructor Details

#initialize(bucket_threshold_size: BUCKET_THRESHOLD_SIZE_DEFAULT, bucket_max_age: BUCKET_MAX_AGE_DEFAULT) ⇒ InMemory

Creates a new in memory Bucketer with the requested configurations

after which the on_bucket_full callback is called can remain before the on_bucket_timed_out is called

Parameters:

  • bucket_threshold_size (Integer) (defaults to: BUCKET_THRESHOLD_SIZE_DEFAULT) —

    the max size of the bucket

  • bucket_max_age (Integer) (defaults to: BUCKET_MAX_AGE_DEFAULT) —

    max number of seconds a bucket



24
25
26
27
28
29
 
# File 'lib/bucketer/in_memory.rb', line 24

def initialize(bucket_threshold_size: BUCKET_THRESHOLD_SIZE_DEFAULT, bucket_max_age: BUCKET_MAX_AGE_DEFAULT)
  @bucket_threshold_size = bucket_threshold_size
  @bucket_max_age = bucket_max_age
  @buckets = {}
  @on_bucket_full_callbacks = []
end

Instance Method Details

#add_item(bucket_id, item_id, item, &blk) ⇒ Object

Adds a item to the specified bucket and calls the block when it is done

the bucket to put the item in of the item (used to ensure uniqueness within a bucket) placed in the bucket

Parameters:

  • bucket_id (String) —

    the bucket id of

  • item_id (String) —

    the item_id

  • item (Object) —

    the item to be



41
42
43
44
45
46
47
 
# File 'lib/bucketer/in_memory.rb', line 41

def add_item(bucket_id, item_id, item, &blk)
  EM::Completion.new.tap do |c|
    c.callback(&blk) if block_given?
    add_bucket_to_db(bucket_id, item_id, item) { c.succeed }
    check_bucket_full(bucket_id)
  end
end

#empty_bucket(bucket_id, &blk) ⇒ Object

Empty a bucket

of the bucket you want to empty

Parameters:

  • bucket_id (String) —

    the bucket id



98
99
100
101
102
103
104
105
 
# File 'lib/bucketer/in_memory.rb', line 98

def empty_bucket(bucket_id, &blk)
  EM::Completion.new.tap do |c|
    c.callback(&blk) if block_given?
    empty_bucket_in_db(bucket_id) do
      c.succeed
    end
  end
end

#get_and_empty_bucket(bucket_id) {|Array| ... } ⇒ Object

Get the contents of a bucket then empty it

of the bucket you want to get into the bucket

Parameters:

  • bucket_id (String) —

    the bucket id

Yields:

  • (Array) —

    the items you put



83
84
85
86
87
88
89
90
91
92
 
# File 'lib/bucketer/in_memory.rb', line 83

def get_and_empty_bucket(bucket_id, &blk)
  EM::Completion.new.tap do |c|
    c.callback(&blk) if block_given?
    get_bucket(bucket_id) do |contents|
      empty_bucket(bucket_id) do
        c.succeed contents
      end
    end
  end
end

#get_bucket(bucket_id) {|Array| ... } ⇒ Object

Get the contents of a bucket.

of the bucket you want to get into the bucket

Parameters:

  • bucket_id (String) —

    the bucket id

Yields:

  • (Array) —

    the items you put



68
69
70
71
72
73
74
75
 
# File 'lib/bucketer/in_memory.rb', line 68

def get_bucket(bucket_id, &blk)
  EM::Completion.new.tap do |c|
    c.callback(&blk) if block_given?
    get_bucket_from_db(bucket_id) do |bucket|
      c.succeed bucket.values
    end
  end
end

#on_bucket_full {|String| ... } ⇒ Object

Used to set a callback hook for when a bucket reaches the threshold size. It is IMPORTANT to note that the bucket will not automatically be emptied you must call empty_bucket if you want the bucket to be emptied. Also the callback will be called every time a item is added until the bucket is emptied.

Yields:

  • (String) —

    The bucket id of the full bucket



58
59
60
 
# File 'lib/bucketer/in_memory.rb', line 58

def on_bucket_full(&blk)
  @on_bucket_full_callbacks << blk
end