Class: CassandraObject::Adapters::CassandraSchemalessAdapter

Inherits:
AbstractAdapter
  • Object
show all
Defined in:
lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb

Defined Under Namespace

Classes: QueryBuilder

Instance Attribute Summary

Attributes inherited from AbstractAdapter

#config

Instance Method Summary collapse

Methods inherited from AbstractAdapter

#batch, #batching?, #execute_batchable, #initialize, #statement_with_options

Constructor Details

This class inherits a constructor from CassandraObject::Adapters::AbstractAdapter

Instance Method Details

#cassandra_cluster_options ⇒ Object 



64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
 
# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 64

def cassandra_cluster_options
  cluster_options = config.slice(*[
      :auth_provider,
      :client_cert,
      :compression,
      :compressor,
      :connect_timeout,
      :connections_per_local_node,
      :connections_per_remote_node,
      :consistency,
      :credentials,
      :futures_factory,
      :hosts,
      :load_balancing_policy,
      :logger,
      :page_size,
      :passphrase,
      :password,
      :port,
      :private_key,
      :protocol_version,
      :reconnection_policy,
      :retry_policy,
      :schema_refresh_delay,
      :schema_refresh_timeout,
      :server_cert,
      :ssl,
      :timeout,
      :trace,
      :username
  ])


  {
      load_balancing_policy: 'Cassandra::LoadBalancing::Policies::%s',
      reconnection_policy: 'Cassandra::Reconnection::Policies::%s',
      retry_policy: 'Cassandra::Retry::Policies::%s'
  }.each do |policy_key, class_template|
    if cluster_options[policy_key]
      cluster_options[policy_key] = (class_template % [policy_key.classify]).constantize
    end
  end

  # Setting defaults
  cluster_options.merge!({
                             max_schema_agreement_wait: 1,
                             consistency: cluster_options[:consistency]||:quorum,
                             protocol_version: cluster_options[:protocol_version]||3,
                             page_size: cluster_options[:page_size] || 10000
                         })
  return cluster_options
end

#cassandra_version ⇒ Object 



263
264
265
 
# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 263

def cassandra_version
  @cassandra_version ||= execute('select release_version from system.local').rows.first['release_version'].to_f
end

#connection ⇒ Object 



118
119
120
121
122
123
 
# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 118

def connection
  @connection ||= begin
    cluster = Cassandra.cluster cassandra_cluster_options
    cluster.connect config[:keyspace]
  end
end

#consistency ⇒ Object

/SCHEMA



269
270
271
 
# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 269

def consistency
  defined?(@consistency) ? @consistency : nil
end

#consistency=(val) ⇒ Object 



273
274
275
 
# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 273

def consistency=(val)
  @consistency = val
end

#create_ids_where_clause(ids) ⇒ Object 



318
319
320
321
322
323
 
# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 318

def create_ids_where_clause(ids)
  return ids if ids.empty?
  ids = ids.first if ids.is_a?(Array) && ids.one?
  sql = ids.is_a?(Array) ? "#{primary_key_column} IN (#{ids.map { |id| "'#{id}'" }.join(',')})" : "#{primary_key_column} = ?"
  return sql
end

#create_table(table_name, params = {}) ⇒ Object

SCHEMA



237
238
239
240
241
242
243
244
245
246
 
# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 237

def create_table(table_name, params = {})
  stmt = "CREATE TABLE #{table_name} (" +
      'key text,' +
      'column1 text,' +
      'value text,' +
      'PRIMARY KEY (key, column1)' +
      ')'
  # WITH COMPACT STORAGE
  schema_execute statement_with_options(stmt, params[:options]), config[:keyspace]
end

#delete(table, ids) ⇒ Object 



218
219
220
221
222
223
224
 
# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 218

def delete(table, ids)
  ids = [ids] if !ids.is_a?(Array)
  arguments = nil
  arguments = ids if ids.size == 1
  statement = "DELETE FROM #{table} WHERE #{create_ids_where_clause(ids)}" #.gsub('?', ids.map { |id| "'#{id}'" }.join(','))
  execute(statement, arguments)
end

#drop_table(table_name, confirm = false) ⇒ Object 



248
249
250
251
252
253
254
255
 
# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 248

def drop_table(table_name, confirm = false)
  count = (schema_execute "SELECT count(*) FROM #{table_name}", config[:keyspace]).rows.first['count']
  if confirm || count == 0
    schema_execute "DROP TABLE #{table_name}", config[:keyspace]
  else
    raise "The table #{table_name} is not empty! If you want to drop it add the option confirm = true"
  end
end

#execute(statement, arguments = []) ⇒ Object 



125
126
127
128
129
 
# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 125

def execute(statement, arguments = [])
  ActiveSupport::Notifications.instrument('cql.cassandra_object', cql: statement) do
    connection.execute statement, arguments: arguments, consistency: consistency, page_size: config[:page_size]
  end
end

#execute_async(queries, arguments = [], per_page = nil, next_cursor = nil) ⇒ Object 



131
132
133
134
135
136
137
138
139
140
141
142
 
# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 131

def execute_async(queries, arguments = [], per_page = nil, next_cursor = nil)
  per_page ||= config[:page_size]
  futures = queries.map { |q|
    ActiveSupport::Notifications.instrument('cql.cassandra_object', cql: q) do
      connection.execute_async q, arguments: arguments, consistency: consistency, page_size: per_page, paging_state: next_cursor
    end
  }
  futures.map do |future|
    rows = future.get
    rows
  end
end

#execute_batch(statements) ⇒ Object 



226
227
228
229
230
231
232
233
234
 
# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 226

def execute_batch(statements)
  raise 'No can do' if statements.empty?
  batch = connection.batch do |b|
    statements.each do |statement|
      b.add(statement[:query], arguments: statement[:arguments])
    end
  end
  connection.execute(batch, page_size: config[:page_size])
end

#insert(table, id, attributes, ttl = nil) ⇒ Object 



192
193
194
 
# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 192

def insert(table, id, attributes, ttl = nil)
  write(table, id, attributes, ttl)
end

#pre_select(scope, per_page = nil, next_cursor = nil) ⇒ Object 



144
145
146
147
148
149
150
151
152
153
154
 
# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 144

def pre_select(scope, per_page = nil, next_cursor = nil)
  query = "SELECT DISTINCT #{primary_key_column} FROM #{scope.klass.column_family}"
  query << " LIMIT #{scope.limit_value}" if scope.limit_value == 1
  ids = []
  new_next_cursor = nil
  execute_async([query], nil, per_page, next_cursor).each do |item|
    item.rows.each { |x| ids << x[primary_key_column] }
    new_next_cursor = item.paging_state unless item.last_page?
  end
  return {ids: ids, new_next_cursor: new_next_cursor}
end

#primary_key_column ⇒ Object 



60
61
62
 
# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 60

def primary_key_column
  'key'
end

#schema_execute(cql, keyspace) ⇒ Object 



257
258
259
260
261
 
# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 257

def schema_execute(cql, keyspace)
  schema_db = Cassandra.cluster cassandra_cluster_options
  connection = schema_db.connect keyspace
  connection.execute cql, consistency: consistency
end

#select(scope) ⇒ Object

Raises:



156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
 
# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 156

def select(scope)
  queries = QueryBuilder.new(self, scope).to_query_async
  queries.compact! if queries.present?
  raise CassandraObject::RecordNotFound if !queries.present?

  arguments = scope.select_values.select{ |sv| sv != :column1 }.map(&:to_s)
  arguments += scope.where_values.select.each_with_index{ |_, i| i.odd? }.reject{ |c| c.empty? }.map(&:to_s)
  records = execute_async(queries, arguments).map do |item|
    # pagination
    elems = []
    loop do
      item.rows.each{ |x| elems << x }
      break if item.last_page?
      item = item.next_page
    end
    elems
  end
  {results: records.flatten!}
end

#select_paginated(scope) ⇒ Object

Raises:



176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
 
# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 176

def select_paginated(scope)
  queries = QueryBuilder.new(self, scope).to_query_async
  queries.compact! if queries.present?
  raise CassandraObject::RecordNotFound if !queries.present?

  arguments = scope.select_values.select{ |sv| sv != :column1 }.map(&:to_s)
  arguments += scope.where_values.select.each_with_index{ |_, i| i.odd? }.reject{ |c| c.empty? }.map(&:to_s)
  new_next_cursor = nil
  records = []
  execute_async(queries, arguments, scope.limit_value, scope.next_cursor).each do |item|
    new_next_cursor = item.paging_state unless item.last_page?
    item.rows.each{ |x| records << x }
  end
  return {results: records, new_next_cursor: new_next_cursor}
end

#statement_create_with_options(stmt, options) ⇒ Object 



277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
 
# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 277

def statement_create_with_options(stmt, options)
  if !options.nil?
    statement_with_options stmt, options
  else
    # standard
    if cassandra_version < 3
      "#{stmt} WITH COMPACT STORAGE
        AND bloom_filter_fp_chance = 0.001
        AND CLUSTERING ORDER BY (column1 ASC)
        AND caching = '{\"keys\":\"ALL\", \"rows_per_partition\":\"NONE\"}'
        AND comment = ''
        AND compaction = {'min_sstable_size': '52428800', 'class': 'org.apache.cassandra.db.compaction.SizeTieredCompactionStrategy'}
        AND compression = {'chunk_length_kb': '64', 'sstable_compression': 'org.apache.cassandra.io.compress.LZ4Compressor'}
        AND dclocal_read_repair_chance = 0.0
        AND default_time_to_live = 0
        AND gc_grace_seconds = 864000
        AND max_index_interval = 2048
        AND memtable_flush_period_in_ms = 0
        AND min_index_interval = 128
        AND read_repair_chance = 1.0
        AND speculative_retry = 'NONE';"
    else
      "#{stmt} WITH read_repair_chance = 0.0
        AND dclocal_read_repair_chance = 0.1
        AND gc_grace_seconds = 864000
        AND bloom_filter_fp_chance = 0.01
        AND caching = { 'keys' : 'ALL', 'rows_per_partition' : 'NONE' }
        AND comment = ''
        AND compaction = { 'class' : 'org.apache.cassandra.db.compaction.SizeTieredCompactionStrategy', 'max_threshold' : 32, 'min_threshold' : 4 }
        AND compression = { 'chunk_length_in_kb' : 64, 'class' : 'org.apache.cassandra.io.compress.LZ4Compressor' }
        AND default_time_to_live = 0
        AND speculative_retry = '99PERCENTILE'
        AND min_index_interval = 128
        AND max_index_interval = 2048
        AND crc_check_chance = 1.0;
      "

    end
  end
end

#update(table, id, attributes, ttl = nil) ⇒ Object 



196
197
198
 
# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 196

def update(table, id, attributes, ttl = nil)
  write(table, id, attributes, ttl)
end

#write(table, id, attributes, ttl) ⇒ Object 



200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
 
# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 200

def write(table, id, attributes, ttl)
  queries = []
  # puts attributes
  attributes.each do |column, value|
    if !value.nil?
      query = "INSERT INTO #{table} (#{primary_key_column},column1,value) VALUES (?,?,?)"
      query += " USING TTL #{ttl.to_s}" if !ttl.nil?
      args = [id.to_s, column.to_s, value.to_s]

      queries << {query: query, arguments: args}
    else
      queries << {query: "DELETE FROM #{table} WHERE #{primary_key_column} = ? AND column1= ?", arguments: [id.to_s, column.to_s]}
    end
  end
  execute_batchable(queries)
end