Class: BigRecord::ConnectionAdapters::CassandraAdapter

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# File 'lib/big_record/connection_adapters/cassandra_adapter.rb', line 227

def build_serialized_value(type, value)
  type.chr + value
end

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# File 'lib/big_record/connection_adapters/cassandra_adapter.rb', line 47

def configuration
  @config.clone
end

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# File 'lib/big_record/connection_adapters/cassandra_adapter.rb', line 203

def delete(table_name, row)
  result = nil
  log "DELETE FROM #{table_name} WHERE ROW=#{row};" do
    result = @connection.remove(table_name.to_s, row, {:consistency => Cassandra::Consistency::QUORUM})
  end
  result
end

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# File 'lib/big_record/connection_adapters/cassandra_adapter.rb', line 211

def delete_all(table_name)
  raise NotImplementedError
end

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# File 'lib/big_record/connection_adapters/cassandra_adapter.rb', line 233

def deserialize(str)
  return unless str

  # stay compatible with the old serialization code
  # YAML documents start with "--- " so if we find that sequence at the beginning we
  # consider it as a serialized YAML value, else it's the new format with the type header
  if str[0..3] == "--- "
    YAML::load(str) if str
  else
    deserialize_with_header(str)
  end
end

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# File 'lib/big_record/connection_adapters/cassandra_adapter.rb', line 247

def deserialize_with_header(data)
  return unless data and data.size >= 2

  # the type of the data is encoded in the first byte
  type = data[0];

  case type
  when TYPE_NULL then nil
  when TYPE_STRING then data[1..-1]
  when TYPE_BINARY then data[1..-1]
  else data
  end
end

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# File 'lib/big_record/connection_adapters/cassandra_adapter.rb', line 61

def disconnect!
  @connection.disconnect!
  super
end

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# File 'lib/big_record/connection_adapters/cassandra_adapter.rb', line 92

def get(table_name, row, column, options={})
  serialized_result = get_raw(table_name, row, column, options)
  result = nil
  if serialized_result.is_a?(Array)
    result = serialized_result.collect{|e| deserialize(e)}
  else
    result = deserialize(serialized_result)
  end
  result
end

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# File 'lib/big_record/connection_adapters/cassandra_adapter.rb', line 138

def get_columns(table_name, row, columns, options={})
  row_cols = get_columns_raw(table_name, row, columns, options)
  return nil unless row_cols && !row_cols.empty?

  result = {}
  row_cols.each do |key,value|
    begin
      result[key] =
        if key == 'id'
          value
        else
          deserialize(value)
        end
    rescue Exception => e
      puts "Could not load column value #{key} for row=#{row.name}"
    end
  end
  result
end

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# File 'lib/big_record/connection_adapters/cassandra_adapter.rb', line 103

def get_columns_raw(table_name, row, columns, options={})
  result = {}

  log "SELECT (#{columns.join(", ")}) FROM #{table_name} WHERE ROW=#{row};" do
    prefix_mode = false
    prefixes = []

    columns.each do |name|
      prefix, name = name.split(":")
      prefixes << prefix+":" unless prefixes.include?(prefix+":")
      prefix_mode = name.blank?
    end

    if prefix_mode
      prefixes.sort!
      values = @connection.get(table_name, row, {:start => prefixes.first, :finish => prefixes.last + "~"})

      result["id"] = row if values && values.size > 0

      values.each do |key,value|
        result[key] = value unless value.blank?
      end
    else
      values = @connection.get_columns(table_name, row, columns)

      result["id"] = row if values && values.compact.size > 0

      columns.each_index do |id|
        result[columns[id].to_s] = values[id] unless values[id].blank?
      end
    end
  end
  result
end

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# File 'lib/big_record/connection_adapters/cassandra_adapter.rb', line 186

def get_consecutive_rows(table_name, start_row, limit, columns, stop_row = nil)
  rows = get_consecutive_rows_raw(table_name, start_row, limit, columns, stop_row)

  result = rows.collect do |row|
    cols = {}
    row.each do |key,value|
      begin
        cols[key] = (key == "id") ? value : deserialize(value)
      rescue Exception => e
        puts "Could not load column value #{key} for row=#{row.name}"
      end
    end
    cols
  end
  result
end

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# File 'lib/big_record/connection_adapters/cassandra_adapter.rb', line 158

def get_consecutive_rows_raw(table_name, start_row, limit, columns, stop_row = nil)
  result = []
  log "SCAN (#{columns.join(", ")}) FROM #{table_name} WHERE START_ROW=#{start_row} AND STOP_ROW=#{stop_row} LIMIT=#{limit};" do
    options = {}
    options[:start] = start_row unless start_row.blank?
    options[:finish] = stop_row unless stop_row.blank?
    options[:count] = limit unless limit.blank?

    keys = @connection.get_range(table_name, options)

    # This will be refactored. Don't make fun of me yet.
    if !keys.empty?
      keys.each do |key|
        row = {}
        row["id"] = key.key

        key.columns.each do |col|
          column = col.column
          row[column.name] = column.value
        end

        result << row if row.keys.size > 1
      end
    end
  end
  result
end

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# File 'lib/big_record/connection_adapters/cassandra_adapter.rb', line 84

def get_raw(table_name, row, column, options={})
  result = nil
  log "SELECT (#{column}) FROM #{table_name} WHERE ROW=#{row};" do
    result = @connection.get(table_name, row, column)
  end
  result
end

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# File 'lib/big_record/connection_adapters/cassandra_adapter.rb', line 218

def serialize(value)
  case value
  when NilClass then NULL
  when String then build_serialized_value(TYPE_STRING, value)
  else value.to_yaml
  end
end

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# File 'lib/big_record/connection_adapters/cassandra_adapter.rb', line 55

def supports_migrations? 
  false
end

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# File 'lib/big_record/connection_adapters/cassandra_adapter.rb', line 76

def update(table_name, row, values, timestamp)
  serialized_collection = {}
  values.each do |column, value|
    serialized_collection[column] = serialize(value)
  end
  update_raw(table_name, row, serialized_collection, timestamp)
end

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# File 'lib/big_record/connection_adapters/cassandra_adapter.rb', line 68

def update_raw(table_name, row, values, timestamp)
  result = nil
  log "UPDATE #{table_name} SET #{values.inspect if values} WHERE ROW=#{row};" do
    result = @connection.insert(table_name, row, values, {:consistency => Cassandra::Consistency::QUORUM})
  end
  result
end