SetAttr() public method

SetAttr Method
Set an attribute of the object with the given name and value, where the name is a Python string or unicode object. This method throws a PythonException if the attribute set fails.
public SetAttr ( PyObject name, PyObject value ) : void
name PyObject
value PyObject
return void
Beispiel #1
0
        public static void InvokeSetProperty <T>(IPythonDerivedType obj, string propertyName, T value)
        {
            FieldInfo fi   = obj.GetType().GetField("__pyobj__");
            var       self = (CLRObject)fi.GetValue(obj);

            if (null == self)
            {
                throw new NullReferenceException("Instance must be specified when setting a property");
            }

            IntPtr gs = Runtime.PyGILState_Ensure();

            try
            {
                Runtime.XIncref(self.pyHandle);
                using (var pyself = new PyObject(self.pyHandle))
                    using (var pyvalue = new PyObject(Converter.ToPythonImplicit(value)))
                    {
                        pyself.SetAttr(propertyName, pyvalue);
                    }
            }
            finally
            {
                Runtime.PyGILState_Release(gs);
            }
        }
        public override void SetPyObjAttr(PyObject pyObj, object clrObj)
        {
            var clr_value = this.FieldInfo.GetValue(clrObj);
            var py_value  = this.Converter.ToPython(clr_value);

            pyObj.SetAttr(this.PyPropertyName, py_value);
        }
Beispiel #3
0
        /// <summary>
        /// The actual import hook that ties Python to the managed world.
        /// </summary>
        public static IntPtr __import__(IntPtr self, IntPtr args, IntPtr kw)
        {
            // Replacement for the builtin __import__. The original import
            // hook is saved as this.py_import. This version handles CLR
            // import and defers to the normal builtin for everything else.

            var num_args = Runtime.PyTuple_Size(args);

            if (num_args < 1)
            {
                return(Exceptions.RaiseTypeError("__import__() takes at least 1 argument (0 given)"));
            }

            // borrowed reference
            IntPtr py_mod_name = Runtime.PyTuple_GetItem(args, 0);

            if (py_mod_name == IntPtr.Zero ||
                !Runtime.IsStringType(py_mod_name))
            {
                return(Exceptions.RaiseTypeError("string expected"));
            }

            // Check whether the import is of the form 'from x import y'.
            // This determines whether we return the head or tail module.

            IntPtr fromList = IntPtr.Zero;
            var    fromlist = false;

            if (num_args >= 4)
            {
                fromList = Runtime.PyTuple_GetItem(args, 3);
                if (fromList != IntPtr.Zero &&
                    Runtime.PyObject_IsTrue(fromList) == 1)
                {
                    fromlist = true;
                }
            }

            string mod_name = Runtime.GetManagedString(py_mod_name);

            // Check these BEFORE the built-in import runs; may as well
            // do the Incref()ed return here, since we've already found
            // the module.
            if (mod_name == "clr" || mod_name == "CLR")
            {
                if (mod_name == "CLR")
                {
                    Exceptions.deprecation("The CLR module is deprecated. Please use 'clr'.");
                }
                IntPtr clr_module = GetCLRModule(fromList);
                if (clr_module != IntPtr.Zero)
                {
                    IntPtr sys_modules = Runtime.PyImport_GetModuleDict();
                    if (sys_modules != IntPtr.Zero)
                    {
                        Runtime.PyDict_SetItemString(sys_modules, "clr", clr_module);
                    }
                }
                return(clr_module);
            }

            string realname   = mod_name;
            string clr_prefix = null;

            if (mod_name.StartsWith("CLR."))
            {
                clr_prefix = "CLR."; // prepend when adding the module to sys.modules
                realname   = mod_name.Substring(4);
                string msg = $"Importing from the CLR.* namespace is deprecated. Please import '{realname}' directly.";
                Exceptions.deprecation(msg);
            }
            else
            {
                // 2010-08-15: Always seemed smart to let python try first...
                // This shaves off a few tenths of a second on test_module.py
                // and works around a quirk where 'sys' is found by the
                // LoadImplicit() deprecation logic.
                // Turns out that the AssemblyManager.ResolveHandler() checks to see if any
                // Assembly's FullName.ToLower().StartsWith(name.ToLower()), which makes very
                // little sense to me.
                IntPtr res = Runtime.PyObject_Call(py_import, args, kw);
                if (res != IntPtr.Zero)
                {
                    // There was no error.
                    if (fromlist && IsLoadAll(fromList))
                    {
                        var mod = ManagedType.GetManagedObject(res) as ModuleObject;
                        mod?.LoadNames();
                    }
                    return(res);
                }
                // There was an error
                if (!Exceptions.ExceptionMatches(Exceptions.ImportError))
                {
                    // and it was NOT an ImportError; bail out here.
                    return(IntPtr.Zero);
                }

                if (mod_name == string.Empty)
                {
                    // Most likely a missing relative import.
                    // For example site-packages\bs4\builder\__init__.py uses it to check if a package exists:
                    //     from . import _html5lib
                    // We don't support them anyway
                    return(IntPtr.Zero);
                }
                // Otherwise,  just clear the it.
                Exceptions.Clear();
            }

            string[] names = realname.Split('.');

            // Now we need to decide if the name refers to a CLR module,
            // and may have to do an implicit load (for b/w compatibility)
            // using the AssemblyManager. The assembly manager tries
            // really hard not to use Python objects or APIs, because
            // parts of it can run recursively and on strange threads.
            //
            // It does need an opportunity from time to time to check to
            // see if sys.path has changed, in a context that is safe. Here
            // we know we have the GIL, so we'll let it update if needed.

            AssemblyManager.UpdatePath();
            if (!AssemblyManager.IsValidNamespace(realname))
            {
                var loadExceptions = new List <Exception>();
                if (!AssemblyManager.LoadImplicit(realname, assemblyLoadErrorHandler: loadExceptions.Add))
                {
                    // May be called when a module being imported imports a module.
                    // In particular, I've seen decimal import copy import org.python.core
                    IntPtr importResult = Runtime.PyObject_Call(py_import, args, kw);
                    // TODO: use ModuleNotFoundError in Python 3.6+
                    if (importResult == IntPtr.Zero && loadExceptions.Count > 0 &&
                        Exceptions.ExceptionMatches(Exceptions.ImportError))
                    {
                        loadExceptions.Add(new PythonException());
                        var importError = new PyObject(new BorrowedReference(Exceptions.ImportError));
                        importError.SetAttr("__cause__", new AggregateException(loadExceptions).ToPython());
                        Runtime.PyErr_SetObject(new BorrowedReference(Exceptions.ImportError), importError.Reference);
                    }
                    return(importResult);
                }
            }

            // See if sys.modules for this interpreter already has the
            // requested module. If so, just return the existing module.
            IntPtr modules = Runtime.PyImport_GetModuleDict();
            IntPtr module  = Runtime.PyDict_GetItem(modules, py_mod_name);

            if (module != IntPtr.Zero)
            {
                if (fromlist)
                {
                    if (IsLoadAll(fromList))
                    {
                        var mod = ManagedType.GetManagedObject(module) as ModuleObject;
                        mod?.LoadNames();
                    }
                    Runtime.XIncref(module);
                    return(module);
                }
                if (clr_prefix != null)
                {
                    return(GetCLRModule(fromList));
                }
                module = Runtime.PyDict_GetItemString(modules, names[0]);
                Runtime.XIncref(module);
                return(module);
            }
            Exceptions.Clear();

            // Traverse the qualified module name to get the named module
            // and place references in sys.modules as we go. Note that if
            // we are running in interactive mode we pre-load the names in
            // each module, which is often useful for introspection. If we
            // are not interactive, we stick to just-in-time creation of
            // objects at lookup time, which is much more efficient.
            // NEW: The clr got a new module variable preload. You can
            // enable preloading in a non-interactive python processing by
            // setting clr.preload = True

            ModuleObject head = mod_name == realname ? null : root;
            ModuleObject tail = root;

            root.InitializePreload();

            foreach (string name in names)
            {
                ManagedType mt = tail.GetAttribute(name, true);
                if (!(mt is ModuleObject))
                {
                    Exceptions.SetError(Exceptions.ImportError, $"No module named {name}");
                    return(IntPtr.Zero);
                }
                if (head == null)
                {
                    head = (ModuleObject)mt;
                }
                tail = (ModuleObject)mt;
                if (CLRModule.preload)
                {
                    tail.LoadNames();
                }

                // Add the module to sys.modules
                Runtime.PyDict_SetItemString(modules, tail.moduleName, tail.pyHandle);

                // If imported from CLR add CLR.<modulename> to sys.modules as well
                if (clr_prefix != null)
                {
                    Runtime.PyDict_SetItemString(modules, clr_prefix + tail.moduleName, tail.pyHandle);
                }
            }

            {
                var mod = fromlist ? tail : head;

                if (fromlist && IsLoadAll(fromList))
                {
                    mod.LoadNames();
                }

                Runtime.XIncref(mod.pyHandle);
                return(mod.pyHandle);
            }
        }