ceph/src/mgr/PyModuleRunner.h

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3 /*
   4  * Ceph - scalable distributed file system
   5  *
   6  * Copyright (C) 2016 John Spray <john.spray@redhat.com>
   7  *
   8  * This is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License version 2.1, as published by the Free Software
  11  * Foundation.  See file COPYING.
  12  */
  13
  14
  15 #pragma once
  16
  17 #include "common/Thread.h"
  18 #include "mgr/Gil.h"
  19
  20 /**
  21  * Implement the pattern of calling serve() on a module in a thread,
  22  * until shutdown() is called.
  23  */
  24 class PyModuleRunner
  25 {
  26 protected:
  27   const std::string module_name;
  28
  29   // Passed in by whoever loaded our python module and looked up
  30   // the symbols in it.
  31   PyObject *pClass = nullptr;
  32
  33   // Passed in by whoever created our subinterpreter for us
  34   SafeThreadState pMyThreadState = nullptr;
  35
  36   // Populated when we construct our instance of pClass in load()
  37   PyObject *pClassInstance = nullptr;
  38
  39   class PyModuleRunnerThread : public Thread
  40   {
  41     PyModuleRunner *mod;
  42
  43   public:
  44     PyModuleRunnerThread(PyModuleRunner *mod_)
  45       : mod(mod_) {}
  46
  47     void *entry() override;
  48   };
  49
  50 public:
  51   int serve();
  52   void shutdown();
  53   void log(int level, const std::string &record);
  54
  55   PyModuleRunner(
  56       const std::string &module_name_,
  57       PyObject *pClass_,
  58       const SafeThreadState &pMyThreadState_)
  59     :
  60       module_name(module_name_),
  61       pClass(pClass_), pMyThreadState(pMyThreadState_),
  62       thread(this)
  63   {
  64     assert(pClass != nullptr);
  65     assert(pMyThreadState.ts != nullptr);
  66     assert(!module_name.empty());
  67   }
  68
  69   ~PyModuleRunner();
  70
  71   PyModuleRunnerThread thread;
  72
  73   std::string const &get_name() const { return module_name; }
  74 };
  75
  76