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 



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

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 



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# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 259

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

#connection ⇒ Object 



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# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 114

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

#consistency ⇒ Object

/SCHEMA



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

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

#consistency=(val) ⇒ Object 



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

def consistency=(val)
  @consistency = val
end

#create_ids_where_clause(ids) ⇒ Object 



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# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 314

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



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# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 233

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 



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# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 214

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 



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# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 244

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 



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# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 121

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 



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# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 127

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 



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# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 222

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 



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# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 188

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

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



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# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 140

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 



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# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 56

def primary_key_column
  'key'
end

#schema_execute(cql, keyspace) ⇒ Object 



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# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 253

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:



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# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 152

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:



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# File 'lib/cassandra_object/adapters/cassandra_schemaless_adapter.rb', line 172

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 



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

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 



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

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

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



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

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