Class: Cequel::Metal::Batch Private

Inherits:
Object
  • Object
show all
Defined in:
lib/cequel/metal/batch.rb

Overview

This class is part of a private API. You should avoid using this class if possible, as it may be removed or be changed in the future.

Encapsulates a batch operation

See Also:

  • Keyspace::batch

Since:

  • 1.0.0

Instance Method Summary collapse

Constructor Details

#initialize(keyspace, options = {}) ⇒ Batch

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Returns a new instance of Batch.

Parameters:

  • keyspace (Keyspace) —

    the keyspace that this batch will be executed on

  • options (Hash) (defaults to: {})

Options Hash (options):

  • :auto_apply (Integer) —

    If specified, flush the batch after this many statements have been added.

  • :unlogged (Boolean) — default: false —

    Whether to use an [unlogged batch]( www.datastax.com/dev/blog/atomic-batches-in-cassandra-1-2). Logged batches guarantee atomicity (but not isolation) at the cost of a performance penalty; unlogged batches are useful for bulk write operations but behave the same as discrete writes.

See Also:

Since:

  • 1.0.0



27
28
29
30
31
32
33
34
35
 
# File 'lib/cequel/metal/batch.rb', line 27

def initialize(keyspace, options = {})
  options.assert_valid_keys(:auto_apply, :unlogged, :consistency)
  @keyspace = keyspace
  @auto_apply = options[:auto_apply]
  @unlogged = options.fetch(:unlogged, false)
  @consistency = options.fetch(:consistency,
                               keyspace.default_consistency)
  reset
end

Instance Method Details

#apply ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Send the batch to Cassandra

Since:

  • 1.0.0



54
55
56
57
58
59
60
61
62
63
 
# File 'lib/cequel/metal/batch.rb', line 54

def apply
  return if @statement_count.zero?
  if @statement_count > 1
    @statement.prepend(begin_statement)
    @statement.append("APPLY BATCH\n")
  end
  @keyspace.execute_with_consistency(
    @statement.args.first, @statement.args.drop(1), @consistency)
  execute_on_complete_hooks
end

#execute(cql, *bind_vars) ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Add a statement to the batch.

Parameters:

  • statement (String) —

    CQL string

  • bind_vars (Object) —

    values for bind variables

Since:

  • 1.0.0



42
43
44
45
46
47
48
49
 
# File 'lib/cequel/metal/batch.rb', line 42

def execute(cql, *bind_vars)
  @statement.append("#{cql}\n", *bind_vars)
  @statement_count += 1
  if @auto_apply && @statement_count >= @auto_apply
    apply
    reset
  end
end

#execute_with_consistency(cql, bind_vars, query_consistency) ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Since:

  • 1.0.0



87
88
89
90
91
92
93
94
95
 
# File 'lib/cequel/metal/batch.rb', line 87

def execute_with_consistency(cql, bind_vars, query_consistency)
  if query_consistency && query_consistency != @consistency
    raise ArgumentError,
          "Attempting to perform query with consistency " \
          "#{query_consistency.to_s.upcase} in batch with consistency " \
          "#{@consistency.upcase}"
  end
  execute(cql, *bind_vars)
end

#logged? ⇒ Boolean

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Is this a logged batch?

Returns:

  • (Boolean)

Since:

  • 1.0.0



82
83
84
 
# File 'lib/cequel/metal/batch.rb', line 82

def logged?
  !unlogged?
end

#on_complete(&block) ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Since:

  • 1.0.0



65
66
67
 
# File 'lib/cequel/metal/batch.rb', line 65

def on_complete(&block)
  on_complete_hooks << block
end

#unlogged? ⇒ Boolean

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Is this an unlogged batch?

Returns:

  • (Boolean)

Since:

  • 1.0.0



73
74
75
 
# File 'lib/cequel/metal/batch.rb', line 73

def unlogged?
  @unlogged
end