diff options
Diffstat (limited to 'src/mgr/PyModule.cc')
| -rw-r--r-- | src/mgr/PyModule.cc | 729 |
1 files changed, 729 insertions, 0 deletions
diff --git a/src/mgr/PyModule.cc b/src/mgr/PyModule.cc new file mode 100644 index 000000000..19d02332d --- /dev/null +++ b/src/mgr/PyModule.cc @@ -0,0 +1,729 @@ +// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*- +// vim: ts=8 sw=2 smarttab +/* + * Ceph - scalable distributed file system + * + * Copyright (C) 2017 John Spray <john.spray@redhat.com> + * + * This is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License version 2.1, as published by the Free Software + * Foundation. See file COPYING. + */ + +#include "BaseMgrModule.h" +#include "BaseMgrStandbyModule.h" +#include "PyOSDMap.h" +#include "MgrContext.h" +#include "PyUtil.h" + +#include "PyModule.h" + +#include "common/debug.h" +#include "common/errno.h" +#define dout_context g_ceph_context +#define dout_subsys ceph_subsys_mgr + +#undef dout_prefix +#define dout_prefix *_dout << "mgr[py] " + +// definition for non-const static member +std::string PyModule::mgr_store_prefix = "mgr/"; + +// Courtesy of http://stackoverflow.com/questions/1418015/how-to-get-python-exception-text +#define BOOST_BIND_GLOBAL_PLACEHOLDERS +// Boost apparently can't be bothered to fix its own usage of its own +// deprecated features. +#include <boost/python/extract.hpp> +#include <boost/python/import.hpp> +#include <boost/python/object.hpp> +#undef BOOST_BIND_GLOBAL_PLACEHOLDERS +#include <boost/algorithm/string/predicate.hpp> +#include "include/ceph_assert.h" // boost clobbers this +// decode a Python exception into a string +std::string handle_pyerror() +{ + using namespace boost::python; + using namespace boost; + + PyObject *exc, *val, *tb; + object formatted_list, formatted; + PyErr_Fetch(&exc, &val, &tb); + PyErr_NormalizeException(&exc, &val, &tb); + handle<> hexc(exc), hval(allow_null(val)), htb(allow_null(tb)); + object traceback(import("traceback")); + if (!tb) { + object format_exception_only(traceback.attr("format_exception_only")); + try { + formatted_list = format_exception_only(hexc, hval); + } catch (error_already_set const &) { + // error while processing exception object + // returning only the exception string value + PyObject *name_attr = PyObject_GetAttrString(exc, "__name__"); + std::stringstream ss; + ss << PyUnicode_AsUTF8(name_attr) << ": " << PyUnicode_AsUTF8(val); + Py_XDECREF(name_attr); + ss << "\nError processing exception object: " << peek_pyerror(); + return ss.str(); + } + } else { + object format_exception(traceback.attr("format_exception")); + try { + formatted_list = format_exception(hexc, hval, htb); + } catch (error_already_set const &) { + // error while processing exception object + // returning only the exception string value + PyObject *name_attr = PyObject_GetAttrString(exc, "__name__"); + std::stringstream ss; + ss << PyUnicode_AsUTF8(name_attr) << ": " << PyUnicode_AsUTF8(val); + Py_XDECREF(name_attr); + ss << "\nError processing exception object: " << peek_pyerror(); + return ss.str(); + } + } + formatted = str("").join(formatted_list); + return extract<std::string>(formatted); +} + +/** + * Get the single-line exception message, without clearing any + * exception state. + */ +std::string peek_pyerror() +{ + PyObject *ptype, *pvalue, *ptraceback; + PyErr_Fetch(&ptype, &pvalue, &ptraceback); + ceph_assert(ptype); + ceph_assert(pvalue); + PyObject *pvalue_str = PyObject_Str(pvalue); + std::string exc_msg = PyUnicode_AsUTF8(pvalue_str); + Py_DECREF(pvalue_str); + PyErr_Restore(ptype, pvalue, ptraceback); + + return exc_msg; +} + + +namespace { + PyObject* log_write(PyObject*, PyObject* args) { + char* m = nullptr; + if (PyArg_ParseTuple(args, "s", &m)) { + auto len = strlen(m); + if (len && m[len-1] == '\n') { + m[len-1] = '\0'; + } + dout(4) << m << dendl; + } + Py_RETURN_NONE; + } + + PyObject* log_flush(PyObject*, PyObject*){ + Py_RETURN_NONE; + } + + static PyMethodDef log_methods[] = { + {"write", log_write, METH_VARARGS, "write stdout and stderr"}, + {"flush", log_flush, METH_VARARGS, "flush"}, + {nullptr, nullptr, 0, nullptr} + }; + + static PyModuleDef ceph_logger_module = { + PyModuleDef_HEAD_INIT, + "ceph_logger", + nullptr, + -1, + log_methods, + }; +} + +PyModuleConfig::PyModuleConfig() = default; + +PyModuleConfig::PyModuleConfig(PyModuleConfig &mconfig) + : config(mconfig.config) +{} + +PyModuleConfig::~PyModuleConfig() = default; + + +void PyModuleConfig::set_config( + MonClient *monc, + const std::string &module_name, + const std::string &key, const boost::optional<std::string>& val) +{ + const std::string global_key = "mgr/" + module_name + "/" + key; + Command set_cmd; + { + std::ostringstream cmd_json; + JSONFormatter jf; + jf.open_object_section("cmd"); + if (val) { + jf.dump_string("prefix", "config set"); + jf.dump_string("value", *val); + } else { + jf.dump_string("prefix", "config rm"); + } + jf.dump_string("who", "mgr"); + jf.dump_string("name", global_key); + jf.close_section(); + jf.flush(cmd_json); + set_cmd.run(monc, cmd_json.str()); + } + set_cmd.wait(); + + if (set_cmd.r == 0) { + std::lock_guard l(lock); + if (val) { + config[global_key] = *val; + } else { + config.erase(global_key); + } + } else { + if (val) { + dout(0) << "`config set mgr " << global_key << " " << val << "` failed: " + << cpp_strerror(set_cmd.r) << dendl; + } else { + dout(0) << "`config rm mgr " << global_key << "` failed: " + << cpp_strerror(set_cmd.r) << dendl; + } + dout(0) << "mon returned " << set_cmd.r << ": " << set_cmd.outs << dendl; + } +} + +std::string PyModule::get_site_packages() +{ + std::stringstream site_packages; + + // CPython doesn't auto-add site-packages dirs to sys.path for us, + // but it does provide a module that we can ask for them. + auto site_module = PyImport_ImportModule("site"); + ceph_assert(site_module); + + auto site_packages_fn = PyObject_GetAttrString(site_module, "getsitepackages"); + if (site_packages_fn != nullptr) { + auto site_packages_list = PyObject_CallObject(site_packages_fn, nullptr); + ceph_assert(site_packages_list); + + auto n = PyList_Size(site_packages_list); + for (Py_ssize_t i = 0; i < n; ++i) { + if (i != 0) { + site_packages << ":"; + } + site_packages << PyUnicode_AsUTF8(PyList_GetItem(site_packages_list, i)); + } + + Py_DECREF(site_packages_list); + Py_DECREF(site_packages_fn); + } else { + // Fall back to generating our own site-packages paths by imitating + // what the standard site.py does. This is annoying but it lets us + // run inside virtualenvs :-/ + + auto site_packages_fn = PyObject_GetAttrString(site_module, "addsitepackages"); + ceph_assert(site_packages_fn); + + auto known_paths = PySet_New(nullptr); + auto pArgs = PyTuple_Pack(1, known_paths); + PyObject_CallObject(site_packages_fn, pArgs); + Py_DECREF(pArgs); + Py_DECREF(known_paths); + Py_DECREF(site_packages_fn); + + auto sys_module = PyImport_ImportModule("sys"); + ceph_assert(sys_module); + auto sys_path = PyObject_GetAttrString(sys_module, "path"); + ceph_assert(sys_path); + + dout(1) << "sys.path:" << dendl; + auto n = PyList_Size(sys_path); + bool first = true; + for (Py_ssize_t i = 0; i < n; ++i) { + dout(1) << " " << PyUnicode_AsUTF8(PyList_GetItem(sys_path, i)) << dendl; + if (first) { + first = false; + } else { + site_packages << ":"; + } + site_packages << PyUnicode_AsUTF8(PyList_GetItem(sys_path, i)); + } + + Py_DECREF(sys_path); + Py_DECREF(sys_module); + } + + Py_DECREF(site_module); + + return site_packages.str(); +} + +PyObject* PyModule::init_ceph_logger() +{ + auto py_logger = PyModule_Create(&ceph_logger_module); + PySys_SetObject("stderr", py_logger); + PySys_SetObject("stdout", py_logger); + return py_logger; +} + +PyObject* PyModule::init_ceph_module() +{ + static PyMethodDef module_methods[] = { + {nullptr, nullptr, 0, nullptr} + }; + static PyModuleDef ceph_module_def = { + PyModuleDef_HEAD_INIT, + "ceph_module", + nullptr, + -1, + module_methods, + nullptr, + nullptr, + nullptr, + nullptr + }; + PyObject *ceph_module = PyModule_Create(&ceph_module_def); + ceph_assert(ceph_module != nullptr); + std::map<const char*, PyTypeObject*> classes{ + {{"BaseMgrModule", &BaseMgrModuleType}, + {"BaseMgrStandbyModule", &BaseMgrStandbyModuleType}, + {"BasePyOSDMap", &BasePyOSDMapType}, + {"BasePyOSDMapIncremental", &BasePyOSDMapIncrementalType}, + {"BasePyCRUSH", &BasePyCRUSHType}} + }; + for (auto [name, type] : classes) { + type->tp_new = PyType_GenericNew; + if (PyType_Ready(type) < 0) { + ceph_abort(); + } + Py_INCREF(type); + + PyModule_AddObject(ceph_module, name, (PyObject *)type); + } + return ceph_module; +} + +int PyModule::load(PyThreadState *pMainThreadState) +{ + ceph_assert(pMainThreadState != nullptr); + + // Configure sub-interpreter + { + SafeThreadState sts(pMainThreadState); + Gil gil(sts); + + auto thread_state = Py_NewInterpreter(); + if (thread_state == nullptr) { + derr << "Failed to create python sub-interpreter for '" << module_name << '"' << dendl; + return -EINVAL; + } else { + pMyThreadState.set(thread_state); + // Some python modules do not cope with an unpopulated argv, so lets + // fake one. This step also picks up site-packages into sys.path. + const wchar_t *argv[] = {L"ceph-mgr"}; + PySys_SetArgv(1, (wchar_t**)argv); + // Configure sys.path to include mgr_module_path + string paths = (g_conf().get_val<std::string>("mgr_module_path") + ':' + + get_site_packages() + ':'); + wstring sys_path(wstring(begin(paths), end(paths)) + Py_GetPath()); + PySys_SetPath(const_cast<wchar_t*>(sys_path.c_str())); + dout(10) << "Computed sys.path '" + << string(begin(sys_path), end(sys_path)) << "'" << dendl; + } + } + // Environment is all good, import the external module + { + Gil gil(pMyThreadState); + + int r; + r = load_subclass_of("MgrModule", &pClass); + if (r) { + derr << "Class not found in module '" << module_name << "'" << dendl; + return r; + } + + r = load_commands(); + if (r != 0) { + derr << "Missing or invalid COMMANDS attribute in module '" + << module_name << "'" << dendl; + error_string = "Missing or invalid COMMANDS attribute"; + return r; + } + + register_options(pClass); + r = load_options(); + if (r != 0) { + derr << "Missing or invalid MODULE_OPTIONS attribute in module '" + << module_name << "'" << dendl; + error_string = "Missing or invalid MODULE_OPTIONS attribute"; + return r; + } + + load_notify_types(); + + // We've imported the module and found a MgrModule subclass, at this + // point the module is considered loaded. It might still not be + // runnable though, can_run populated later... + loaded = true; + + r = load_subclass_of("MgrStandbyModule", &pStandbyClass); + if (!r) { + dout(4) << "Standby mode available in module '" << module_name + << "'" << dendl; + register_options(pStandbyClass); + } else { + dout(4) << "Standby mode not provided by module '" << module_name + << "'" << dendl; + } + + // Populate can_run by interrogating the module's callback that + // may check for dependencies etc + PyObject *pCanRunTuple = PyObject_CallMethod(pClass, + const_cast<char*>("can_run"), const_cast<char*>("()")); + if (pCanRunTuple != nullptr) { + if (PyTuple_Check(pCanRunTuple) && PyTuple_Size(pCanRunTuple) == 2) { + PyObject *pCanRun = PyTuple_GetItem(pCanRunTuple, 0); + PyObject *can_run_str = PyTuple_GetItem(pCanRunTuple, 1); + if (!PyBool_Check(pCanRun) || !PyUnicode_Check(can_run_str)) { + derr << "Module " << get_name() + << " returned wrong type in can_run" << dendl; + error_string = "wrong type returned from can_run"; + can_run = false; + } else { + can_run = (pCanRun == Py_True); + if (!can_run) { + error_string = PyUnicode_AsUTF8(can_run_str); + dout(4) << "Module " << get_name() + << " reported that it cannot run: " + << error_string << dendl; + } + } + } else { + derr << "Module " << get_name() + << " returned wrong type in can_run" << dendl; + error_string = "wrong type returned from can_run"; + can_run = false; + } + + Py_DECREF(pCanRunTuple); + } else { + derr << "Exception calling can_run on " << get_name() << dendl; + derr << handle_pyerror() << dendl; + can_run = false; + } + } + return 0; +} + +int PyModule::walk_dict_list( + const std::string &attr_name, + std::function<int(PyObject*)> fn) +{ + PyObject *command_list = PyObject_GetAttrString(pClass, attr_name.c_str()); + if (command_list == nullptr) { + derr << "Module " << get_name() << " has missing " << attr_name + << " member" << dendl; + return -EINVAL; + } + if (!PyObject_TypeCheck(command_list, &PyList_Type)) { + // Relatively easy mistake for human to make, e.g. defining COMMANDS + // as a {} instead of a [] + derr << "Module " << get_name() << " has " << attr_name + << " member of wrong type (should be a list)" << dendl; + return -EINVAL; + } + + // Invoke fn on each item in the list + int r = 0; + const size_t list_size = PyList_Size(command_list); + for (size_t i = 0; i < list_size; ++i) { + PyObject *command = PyList_GetItem(command_list, i); + ceph_assert(command != nullptr); + + if (!PyDict_Check(command)) { + derr << "Module " << get_name() << " has non-dict entry " + << "in " << attr_name << " list" << dendl; + return -EINVAL; + } + + r = fn(command); + if (r != 0) { + break; + } + } + Py_DECREF(command_list); + + return r; +} + +int PyModule::register_options(PyObject *cls) +{ + PyObject *pRegCmd = PyObject_CallMethod( + cls, + const_cast<char*>("_register_options"), const_cast<char*>("(s)"), + module_name.c_str()); + if (pRegCmd != nullptr) { + Py_DECREF(pRegCmd); + } else { + derr << "Exception calling _register_options on " << get_name() + << dendl; + derr << handle_pyerror() << dendl; + } + return 0; +} + +int PyModule::load_notify_types() +{ + PyObject *ls = PyObject_GetAttrString(pClass, "NOTIFY_TYPES"); + if (ls == nullptr) { + derr << "Module " << get_name() << " has missing NOTIFY_TYPES member" << dendl; + return -EINVAL; + } + if (!PyObject_TypeCheck(ls, &PyList_Type)) { + // Relatively easy mistake for human to make, e.g. defining COMMANDS + // as a {} instead of a [] + derr << "Module " << get_name() << " has NOTIFY_TYPES that is not a list" << dendl; + return -EINVAL; + } + + const size_t list_size = PyList_Size(ls); + for (size_t i = 0; i < list_size; ++i) { + PyObject *notify_type = PyList_GetItem(ls, i); + ceph_assert(notify_type != nullptr); + + if (!PyObject_TypeCheck(notify_type, &PyUnicode_Type)) { + derr << "Module " << get_name() << " has non-string entry in NOTIFY_TYPES list" + << dendl; + return -EINVAL; + } + + notify_types.insert(PyUnicode_AsUTF8(notify_type)); + } + Py_DECREF(ls); + dout(10) << "Module " << get_name() << " notify_types " << notify_types << dendl; + + return 0; +} + +int PyModule::load_commands() +{ + PyObject *pRegCmd = PyObject_CallMethod(pClass, + const_cast<char*>("_register_commands"), const_cast<char*>("(s)"), + module_name.c_str()); + if (pRegCmd != nullptr) { + Py_DECREF(pRegCmd); + } else { + derr << "Exception calling _register_commands on " << get_name() + << dendl; + derr << handle_pyerror() << dendl; + } + + int r = walk_dict_list("COMMANDS", [this](PyObject *pCommand) -> int { + ModuleCommand command; + + PyObject *pCmd = PyDict_GetItemString(pCommand, "cmd"); + ceph_assert(pCmd != nullptr); + command.cmdstring = PyUnicode_AsUTF8(pCmd); + + dout(20) << "loaded command " << command.cmdstring << dendl; + + PyObject *pDesc = PyDict_GetItemString(pCommand, "desc"); + ceph_assert(pDesc != nullptr); + command.helpstring = PyUnicode_AsUTF8(pDesc); + + PyObject *pPerm = PyDict_GetItemString(pCommand, "perm"); + ceph_assert(pPerm != nullptr); + command.perm = PyUnicode_AsUTF8(pPerm); + + command.polling = false; + if (PyObject *pPoll = PyDict_GetItemString(pCommand, "poll"); + pPoll && PyObject_IsTrue(pPoll)) { + command.polling = true; + } + + command.module_name = module_name; + + commands.push_back(std::move(command)); + + return 0; + }); + + dout(10) << "loaded " << commands.size() << " commands" << dendl; + + return r; +} + +int PyModule::load_options() +{ + int r = walk_dict_list("MODULE_OPTIONS", [this](PyObject *pOption) -> int { + MgrMap::ModuleOption option; + PyObject *p; + p = PyDict_GetItemString(pOption, "name"); + ceph_assert(p != nullptr); + option.name = PyUnicode_AsUTF8(p); + option.type = Option::TYPE_STR; + p = PyDict_GetItemString(pOption, "type"); + if (p && PyObject_TypeCheck(p, &PyUnicode_Type)) { + std::string s = PyUnicode_AsUTF8(p); + int t = Option::str_to_type(s); + if (t >= 0) { + option.type = t; + } + } + p = PyDict_GetItemString(pOption, "desc"); + if (p && PyObject_TypeCheck(p, &PyUnicode_Type)) { + option.desc = PyUnicode_AsUTF8(p); + } + p = PyDict_GetItemString(pOption, "long_desc"); + if (p && PyObject_TypeCheck(p, &PyUnicode_Type)) { + option.long_desc = PyUnicode_AsUTF8(p); + } + p = PyDict_GetItemString(pOption, "default"); + if (p) { + auto q = PyObject_Str(p); + option.default_value = PyUnicode_AsUTF8(q); + Py_DECREF(q); + } + p = PyDict_GetItemString(pOption, "min"); + if (p) { + auto q = PyObject_Str(p); + option.min = PyUnicode_AsUTF8(q); + Py_DECREF(q); + } + p = PyDict_GetItemString(pOption, "max"); + if (p) { + auto q = PyObject_Str(p); + option.max = PyUnicode_AsUTF8(q); + Py_DECREF(q); + } + p = PyDict_GetItemString(pOption, "enum_allowed"); + if (p && PyObject_TypeCheck(p, &PyList_Type)) { + for (unsigned i = 0; i < PyList_Size(p); ++i) { + auto q = PyList_GetItem(p, i); + if (q) { + auto r = PyObject_Str(q); + option.enum_allowed.insert(PyUnicode_AsUTF8(r)); + Py_DECREF(r); + } + } + } + p = PyDict_GetItemString(pOption, "see_also"); + if (p && PyObject_TypeCheck(p, &PyList_Type)) { + for (unsigned i = 0; i < PyList_Size(p); ++i) { + auto q = PyList_GetItem(p, i); + if (q && PyObject_TypeCheck(q, &PyUnicode_Type)) { + option.see_also.insert(PyUnicode_AsUTF8(q)); + } + } + } + p = PyDict_GetItemString(pOption, "tags"); + if (p && PyObject_TypeCheck(p, &PyList_Type)) { + for (unsigned i = 0; i < PyList_Size(p); ++i) { + auto q = PyList_GetItem(p, i); + if (q && PyObject_TypeCheck(q, &PyUnicode_Type)) { + option.tags.insert(PyUnicode_AsUTF8(q)); + } + } + } + p = PyDict_GetItemString(pOption, "runtime"); + if (p && PyObject_TypeCheck(p, &PyBool_Type)) { + if (p == Py_True) { + option.flags |= Option::FLAG_RUNTIME; + } + if (p == Py_False) { + option.flags &= ~Option::FLAG_RUNTIME; + } + } + dout(20) << "loaded module option " << option.name << dendl; + options[option.name] = std::move(option); + return 0; + }); + + dout(10) << "loaded " << options.size() << " options" << dendl; + + return r; +} + +bool PyModule::is_option(const std::string &option_name) +{ + std::lock_guard l(lock); + return options.count(option_name) > 0; +} + +PyObject *PyModule::get_typed_option_value(const std::string& name, + const std::string& value) +{ + // we don't need to hold a lock here because these MODULE_OPTIONS + // are set up exactly once during startup. + auto p = options.find(name); + if (p != options.end()) { + return get_python_typed_option_value((Option::type_t)p->second.type, value); + } + return PyUnicode_FromString(value.c_str()); +} + +int PyModule::load_subclass_of(const char* base_class, PyObject** py_class) +{ + // load the base class + PyObject *mgr_module = PyImport_ImportModule("mgr_module"); + if (!mgr_module) { + error_string = peek_pyerror(); + derr << "Module not found: 'mgr_module'" << dendl; + derr << handle_pyerror() << dendl; + return -EINVAL; + } + auto mgr_module_type = PyObject_GetAttrString(mgr_module, base_class); + Py_DECREF(mgr_module); + if (!mgr_module_type) { + error_string = peek_pyerror(); + derr << "Unable to import MgrModule from mgr_module" << dendl; + derr << handle_pyerror() << dendl; + return -EINVAL; + } + + // find the sub class + PyObject *plugin_module = PyImport_ImportModule(module_name.c_str()); + if (!plugin_module) { + error_string = peek_pyerror(); + derr << "Module not found: '" << module_name << "'" << dendl; + derr << handle_pyerror() << dendl; + return -ENOENT; + } + auto locals = PyModule_GetDict(plugin_module); + Py_DECREF(plugin_module); + PyObject *key, *value; + Py_ssize_t pos = 0; + *py_class = nullptr; + while (PyDict_Next(locals, &pos, &key, &value)) { + if (!PyType_Check(value)) { + continue; + } + if (!PyObject_IsSubclass(value, mgr_module_type)) { + continue; + } + if (PyObject_RichCompareBool(value, mgr_module_type, Py_EQ)) { + continue; + } + auto class_name = PyUnicode_AsUTF8(key); + if (*py_class) { + derr << __func__ << ": ignoring '" + << module_name << "." << class_name << "'" + << ": only one '" << base_class + << "' class is loaded from each plugin" << dendl; + continue; + } + *py_class = value; + dout(4) << __func__ << ": found class: '" + << module_name << "." << class_name << "'" << dendl; + } + Py_DECREF(mgr_module_type); + + return *py_class ? 0 : -EINVAL; +} + +PyModule::~PyModule() +{ + if (pMyThreadState.ts != nullptr) { + Gil gil(pMyThreadState, true); + Py_XDECREF(pClass); + Py_XDECREF(pStandbyClass); + } +} + |