Apache Thrift ™

Python Tutorial

Introduction

All Apache Thrift tutorials require that you have:

  1. Built and installed the Apache Thrift Compiler and Libraries, see Building from source for more details.

  2. Generated the tutorial.thrift and shared.thrift files as discussed here

    thrift -r --gen py tutorial.thrift

  3. Followed all prerequesets listed

Prerequisites

Client

import sys, glob
sys.path.append('gen-py')
sys.path.insert(0, glob.glob('../../lib/py/build/lib.*')[0])

from tutorial import Calculator
from tutorial.ttypes import *

from thrift import Thrift
from thrift.transport import TSocket
from thrift.transport import TTransport
from thrift.protocol import TBinaryProtocol

try:

  # Make socket
  transport = TSocket.TSocket('localhost', 9090)

  # Buffering is critical. Raw sockets are very slow
  transport = TTransport.TBufferedTransport(transport)

  # Wrap in a protocol
  protocol = TBinaryProtocol.TBinaryProtocol(transport)

  # Create a client to use the protocol encoder
  client = Calculator.Client(protocol)

  # Connect!
  transport.open()

  client.ping()
  print 'ping()'

  sum = client.add(1,1)
  print '1+1=%d' % (sum)

  work = Work()

  work.op = Operation.DIVIDE
  work.num1 = 1
  work.num2 = 0

  try:
    quotient = client.calculate(1, work)
    print 'Whoa? You know how to divide by zero?'
  except InvalidOperation, io:
    print 'InvalidOperation: %r' % io

  work.op = Operation.SUBTRACT
  work.num1 = 15
  work.num2 = 10

  diff = client.calculate(1, work)
  print '15-10=%d' % (diff)

  log = client.getStruct(1)
  print 'Check log: %s' % (log.value)

  # Close!
  transport.close()

except Thrift.TException, tx:
  print '%s' % (tx.message)

Server

import sys, glob
sys.path.append('gen-py')
sys.path.insert(0, glob.glob('../../lib/py/build/lib.*')[0])

from tutorial import Calculator
from tutorial.ttypes import *

from shared.ttypes import SharedStruct

from thrift.transport import TSocket
from thrift.transport import TTransport
from thrift.protocol import TBinaryProtocol
from thrift.server import TServer

class CalculatorHandler:
  def __init__(self):
    self.log = {}

  def ping(self):
    print 'ping()'

  def add(self, n1, n2):
    print 'add(%d,%d)' % (n1, n2)
    return n1+n2

  def calculate(self, logid, work):
    print 'calculate(%d, %r)' % (logid, work)

    if work.op == Operation.ADD:
      val = work.num1 + work.num2
    elif work.op == Operation.SUBTRACT:
      val = work.num1 - work.num2
    elif work.op == Operation.MULTIPLY:
      val = work.num1 * work.num2
    elif work.op == Operation.DIVIDE:
      if work.num2 == 0:
        x = InvalidOperation()
        x.what = work.op
        x.why = 'Cannot divide by 0'
        raise x
      val = work.num1 / work.num2
    else:
      x = InvalidOperation()
      x.what = work.op
      x.why = 'Invalid operation'
      raise x

    log = SharedStruct()
    log.key = logid
    log.value = '%d' % (val)
    self.log[logid] = log

    return val

  def getStruct(self, key):
    print 'getStruct(%d)' % (key)
    return self.log[key]

  def zip(self):
    print 'zip()'

handler = CalculatorHandler()
processor = Calculator.Processor(handler)
transport = TSocket.TServerSocket(port=9090)
tfactory = TTransport.TBufferedTransportFactory()
pfactory = TBinaryProtocol.TBinaryProtocolFactory()

server = TServer.TSimpleServer(processor, transport, tfactory, pfactory)

# You could do one of these for a multithreaded server
#server = TServer.TThreadedServer(processor, transport, tfactory, pfactory)
#server = TServer.TThreadPoolServer(processor, transport, tfactory, pfactory)

print 'Starting the server...'
server.serve()
print 'done.'

Additional Information