Class: Impala::Connection

Inherits:
Object
  • Object
show all
Defined in:
lib/impala/connection.rb

Constant Summary collapse

SLEEP_INTERVAL = 
0.1

Instance Method Summary collapse

Constructor Details

#initialize(host, port) ⇒ Connection

Returns a new instance of Connection.



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# File 'lib/impala/connection.rb', line 5

def initialize(host, port)
  @host = host
  @port = port
  @connected = false
  open
end

Instance Method Details

#close ⇒ Object 



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# File 'lib/impala/connection.rb', line 25

def close
  @transport.close
  @connected = false
end

#execute(raw_query) ⇒ Object

Raises:



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# File 'lib/impala/connection.rb', line 38

def execute(raw_query)
  raise ConnectionError.new("Connection closed") unless open?

  query = sanitize_query(raw_query)
  handle = send_query(query)

  wait_for_result(handle)
  Cursor.new(handle, @service)
end

#open ⇒ Object 



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# File 'lib/impala/connection.rb', line 12

def open
  return if @connected

  socket = Thrift::Socket.new(@host, @port)

  @transport = Thrift::BufferedTransport.new(socket)
  @transport.open

  proto = Thrift::BinaryProtocol.new(@transport)
  @service = Protocol::ImpalaService::Client.new(proto)
  @connected = true
end

#open? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/impala/connection.rb', line 30

def open?
  @connected
end

#query(raw_query) ⇒ Object 



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# File 'lib/impala/connection.rb', line 34

def query(raw_query)
  execute(raw_query).fetch_all
end