library loading api.

this is not well suited to RNA so this is a native python api.

This uses:
  bpy.data.libraries.load(filepath, link=False, relative=False)

however the return value needs to use pythons context manager, this means the library loading is confined to a block of code and python cant leave a half loaded library state.


eg, load a single scene we know the name of:
  with bpy.data.libraries.load(filepath) as (data_from, data_to):
      data_to.scenes = ["Scene"]


eg, load all scenes:
  with bpy.data.libraries.load(filepath) as (data_from, data_to):
      data_to.scenes = data_from.scenes


eg, load all objects starting with 'A'
  with bpy.data.libraries.load(filepath) as (data_from, data_to):
      data_to.objects = [name for name in data_from.objects if name.startswith("A")]

As you can see gives 2 objects like 'bpy.data', but containing lists of strings which can be moved from one into another.

5 files changed, 342 insertions, 18 deletions

diff --git a/release/scripts/modules/bpy_types.py b/release/scripts/modules/bpy_types.py
index 7c8f767f327..eff59668e9c 100644
--- a/release/scripts/modules/bpy_types.py
+++ b/release/scripts/modules/bpy_types.py
@@ -26,6 +26,7 @@ StructRNA = bpy_types.Struct.__bases__[0]
 StructMetaPropGroup = _bpy.StructMetaPropGroup
 # StructRNA = bpy_types.Struct
 
+bpy_types.BlendDataLibraries.load = _bpy._library_load
 
 class Context(StructRNA):
     __slots__ = ()
diff --git a/source/blender/python/intern/CMakeLists.txt b/source/blender/python/intern/CMakeLists.txt
index fbf2741533e..ab08dc14f07 100644
--- a/source/blender/python/intern/CMakeLists.txt
+++ b/source/blender/python/intern/CMakeLists.txt
@@ -42,6 +42,7 @@ set(SRC
 	bpy_app.c
 	bpy_driver.c
 	bpy_interface.c
+	bpy_library.c
 	bpy_operator.c
 	bpy_operator_wrap.c
 	bpy_props.c
diff --git a/source/blender/python/intern/bpy.c b/source/blender/python/intern/bpy.c
index 3c3c2be7798..9abe4c9d94b 100644
--- a/source/blender/python/intern/bpy.c
+++ b/source/blender/python/intern/bpy.c
@@ -190,6 +190,7 @@ static PyObject *bpy_import_test(const char *modname)
 void BPy_init_modules( void )
 {
 	extern BPy_StructRNA *bpy_context_module;
+	extern int bpy_lib_init(PyObject *);
 	PointerRNA ctx_ptr;
 	PyObject *mod;
 
@@ -219,7 +220,9 @@ void BPy_init_modules( void )
 
 	PyModule_AddObject( mod, "types", BPY_rna_types() ); /* needs to be first so bpy_types can run */
 	PyModule_AddObject(mod, "StructMetaPropGroup", (PyObject *)&pyrna_struct_meta_idprop_Type); /* metaclass for idprop types, bpy_types.py needs access */
-			
+
+	bpy_lib_init(mod); /* adds '_bpy._library_load', must be called before 'bpy_types' which uses it */
+
 	bpy_import_test("bpy_types");
 	PyModule_AddObject( mod, "data", BPY_rna_module() ); /* imports bpy_types by running this */
 	bpy_import_test("bpy_types");
diff --git a/source/blender/python/intern/bpy_library.c b/source/blender/python/intern/bpy_library.c
new file mode 100644
index 00000000000..20855a31421
--- /dev/null
+++ b/source/blender/python/intern/bpy_library.c
@@ -0,0 +1,331 @@
+/*
+ * $Id:
+ *
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * Contributor(s): Campbell Barton
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+/** \file blender/python/intern/bpy_library.c
+ *  \ingroup pythonintern
+ */
+
+#include <Python.h>
+#include <stddef.h>
+
+#include "BLO_readfile.h"
+
+#include "BKE_global.h"
+#include "BKE_main.h"
+#include "BKE_library.h"
+#include "BKE_idcode.h"
+#include "BKE_report.h"
+
+#include "BLI_utildefines.h"
+#include "BLI_string.h"
+#include "BLI_linklist.h"
+#include "BLI_path_util.h"
+#include "BLI_listbase.h"
+
+#include "DNA_space_types.h" /* FILE_LINK, FILE_RELPATH */
+
+#include "bpy_util.h"
+
+typedef struct {
+	PyObject_HEAD /* required python macro   */
+	/* collection iterator spesific parts */
+	char relpath[FILE_MAX];
+	char abspath[FILE_MAX]; /* absolute path */
+	BlendHandle *blo_handle;
+	int flag;
+	PyObject *dict;
+} BPy_Library;
+
+static PyObject *bpy_lib_load(PyObject *self, PyObject *args, PyObject *kwds);
+static PyObject *bpy_lib_enter(BPy_Library *self, PyObject *args);
+static PyObject *bpy_lib_exit(BPy_Library *self, PyObject *args);
+
+static PyMethodDef bpy_lib_methods[] = {
+	{"__enter__", (PyCFunction)bpy_lib_enter, METH_NOARGS},
+	{"__exit__", (PyCFunction)bpy_lib_exit, METH_VARARGS},
+	{NULL}           /* sentinel */
+};
+
+static void bpy_lib_dealloc(BPy_Library *self)
+{
+	Py_XDECREF(self->dict);
+	Py_TYPE(self)->tp_free(self);
+}
+
+
+PyTypeObject bpy_lib_Type = {
+	PyVarObject_HEAD_INIT(NULL, 0)
+	"bpy_lib",		/* tp_name */
+	sizeof(BPy_Library),			/* tp_basicsize */
+	0,							/* tp_itemsize */
+	/* methods */
+	(destructor)bpy_lib_dealloc,/* tp_dealloc */
+	NULL,                       /* printfunc tp_print; */
+	NULL,						/* getattrfunc tp_getattr; */
+	NULL,                       /* setattrfunc tp_setattr; */
+	NULL,						/* tp_compare */ /* DEPRECATED in python 3.0! */
+	NULL,						/* tp_repr */
+
+	/* Method suites for standard classes */
+
+	NULL,						/* PyNumberMethods *tp_as_number; */
+	NULL,						/* PySequenceMethods *tp_as_sequence; */
+	NULL,						/* PyMappingMethods *tp_as_mapping; */
+
+	/* More standard operations (here for binary compatibility) */
+
+	NULL,						/* hashfunc tp_hash; */
+	NULL,                       /* ternaryfunc tp_call; */
+	NULL,                       /* reprfunc tp_str; */
+
+	/* will only use these if this is a subtype of a py class */
+	PyObject_GenericGetAttr,	/* getattrofunc tp_getattro; */
+	NULL,						/* setattrofunc tp_setattro; */
+
+	/* Functions to access object as input/output buffer */
+	NULL,                       /* PyBufferProcs *tp_as_buffer; */
+
+  /*** Flags to define presence of optional/expanded features ***/
+	Py_TPFLAGS_DEFAULT,         /* long tp_flags; */
+
+	NULL,						/*  char *tp_doc;  Documentation string */
+  /*** Assigned meaning in release 2.0 ***/
+	/* call function for all accessible objects */
+	NULL,                       /* traverseproc tp_traverse; */
+
+	/* delete references to contained objects */
+	NULL,                       /* inquiry tp_clear; */
+
+  /***  Assigned meaning in release 2.1 ***/
+  /*** rich comparisons ***/
+	NULL, /* subclassed */		/* richcmpfunc tp_richcompare; */
+
+  /***  weak reference enabler ***/
+	0,
+  /*** Added in release 2.2 ***/
+	/*   Iterators */
+	NULL,						/* getiterfunc tp_iter; */
+	NULL,                       /* iternextfunc tp_iternext; */
+
+  /*** Attribute descriptor and subclassing stuff ***/
+	bpy_lib_methods,			/* struct PyMethodDef *tp_methods; */
+	NULL,                       /* struct PyMemberDef *tp_members; */
+	NULL,				      	/* struct PyGetSetDef *tp_getset; */
+	NULL,                       /* struct _typeobject *tp_base; */
+	NULL,                       /* PyObject *tp_dict; */
+	NULL,                       /* descrgetfunc tp_descr_get; */
+	NULL,                       /* descrsetfunc tp_descr_set; */
+	offsetof(BPy_Library, dict),/* long tp_dictoffset; */
+	NULL,                       /* initproc tp_init; */
+	NULL,                       /* allocfunc tp_alloc; */
+	NULL,						/* newfunc tp_new; */
+	/*  Low-level free-memory routine */
+	NULL,                       /* freefunc tp_free;  */
+	/* For PyObject_IS_GC */
+	NULL,                       /* inquiry tp_is_gc;  */
+	NULL,						/* PyObject *tp_bases; */
+	/* method resolution order */
+	NULL,                       /* PyObject *tp_mro;  */
+	NULL,                       /* PyObject *tp_cache; */
+	NULL,                       /* PyObject *tp_subclasses; */
+	NULL,                       /* PyObject *tp_weaklist; */
+	NULL
+};
+
+
+static PyObject *bpy_lib_load(PyObject *UNUSED(self), PyObject *args, PyObject *kwds)
+{
+	static const char *kwlist[] = {"filepath", "link", "relative", NULL};
+	BPy_Library *ret;
+	const char* filename = NULL;
+	int is_rel= 0, is_link= 0;
+
+	if(!PyArg_ParseTupleAndKeywords(args, kwds, "s|ii:load", (char **)kwlist, &filename, &is_link, &is_rel))
+		return NULL;
+
+	ret= PyObject_New(BPy_Library, &bpy_lib_Type);
+
+	BLI_strncpy(ret->relpath, filename, sizeof(BPy_Library));
+	BLI_strncpy(ret->abspath, filename, sizeof(BPy_Library));
+	BLI_path_abs(ret->abspath, G.main->name);
+
+	ret->blo_handle= NULL;
+	ret->flag=	(is_link ? FILE_LINK : 0) |
+				(is_rel ? FILE_RELPATH : 0);
+
+	ret->dict= PyDict_New();
+
+	return (PyObject *)ret;
+}
+
+static PyObject *_bpy_names(BPy_Library *self, int blocktype)
+{
+	PyObject *list;
+	LinkNode *l, *names;
+	int totnames;
+
+	names= BLO_blendhandle_get_datablock_names(self->blo_handle, blocktype, &totnames);
+
+	if(names) {
+		int counter = 0;
+		list = PyList_New(totnames);
+		for(l = names; l; l = l->next) {
+			PyList_SET_ITEM(list, counter, PyUnicode_FromString((char * )l->link));
+			counter++;
+		}
+		BLI_linklist_free(names, free);	/* free linklist *and* each node's data */
+	}
+	else {
+		list= PyList_New(0);
+	}
+
+	return list;
+}
+
+static PyObject *bpy_lib_enter(BPy_Library *self, PyObject *UNUSED(args))
+{
+	PyObject *ret;
+	BPy_Library *self_from;
+	PyObject *from_dict= PyDict_New();
+	ReportList reports;
+
+	BKE_reports_init(&reports, RPT_STORE);
+
+	self->blo_handle= BLO_blendhandle_from_file(self->abspath, &reports);
+
+	if(self->blo_handle == NULL) {
+		if(BPy_reports_to_error(&reports, PyExc_IOError, TRUE) != -1) {
+			PyErr_Format(PyExc_IOError, "load: %s failed to open blend file", self->abspath);
+		}
+		return NULL;
+	}
+	else {
+		int i= 0, code;
+		while((code= BKE_idcode_iter_step(&i))) {
+			if(BKE_idcode_is_linkable(code)) {
+				const char *name_plural= BKE_idcode_to_name_plural(code);
+				PyObject *str= PyUnicode_FromString(name_plural);
+				PyDict_SetItem(self->dict, str, PyList_New(0));
+				PyDict_SetItem(from_dict, str, _bpy_names(self, code));
+				Py_DECREF(str);
+			}
+		}
+	}
+
+	/* create a dummy */
+	self_from= PyObject_New(BPy_Library, &bpy_lib_Type);
+	BLI_strncpy(self_from->relpath, self->relpath, sizeof(BPy_Library));
+	BLI_strncpy(self_from->abspath, self->abspath, sizeof(BPy_Library));
+
+	self_from->blo_handle= NULL;
+	self_from->flag= 0;
+	self_from->dict= from_dict; /* owns the dict */
+
+	/* return pair */
+	ret= PyTuple_New(2);
+
+	PyTuple_SET_ITEM(ret, 0, (PyObject *)self_from);
+
+	PyTuple_SET_ITEM(ret, 1, (PyObject *)self);
+	Py_INCREF(self);
+
+	BKE_reports_clear(&reports);
+
+	return ret;
+}
+
+static PyObject *bpy_lib_exit(BPy_Library *self, PyObject *UNUSED(args))
+{
+	Main *mainl= NULL;
+
+	flag_all_listbases_ids(LIB_PRE_EXISTING, 1);
+
+	/* here appending/linking starts */
+	mainl = BLO_library_append_begin(BPy_GetContext(), &(self->blo_handle), self->relpath);
+
+	{
+		int i= 0, code;
+		while((code= BKE_idcode_iter_step(&i))) {
+			if(BKE_idcode_is_linkable(code)) {
+				const char *name_plural= BKE_idcode_to_name_plural(code);
+				PyObject *ls= PyDict_GetItemString(self->dict, name_plural);
+				// printf("lib: %s\n", name_plural);
+				if(ls && PyList_Check(ls)) {
+					/* loop */
+					Py_ssize_t size= PyList_GET_SIZE(ls);
+					Py_ssize_t i;
+					PyObject *item;
+					const char *item_str;
+
+					for(i= 0; i < size; i++) {
+						item= PyList_GET_ITEM(ls, i);
+						item_str= _PyUnicode_AsString(item);
+
+						// printf("  %s\n", item_str);
+
+						if(item_str) {
+							BLO_library_append_named_part(NULL, mainl, &(self->blo_handle), item_str, code, self->flag);
+						}
+						else {
+							/* XXX, could complain about this */
+							PyErr_Clear();
+						}
+					}
+				}
+			}
+		}
+	}
+
+	BLO_library_append_end(NULL, mainl, &(self->blo_handle), 0, self->flag);
+	BLO_blendhandle_close(self->blo_handle);
+
+	{	/* copied from wm_operator.c */
+		/* mark all library linked objects to be updated */
+		recalc_all_library_objects(G.main);
+
+		/* append, rather than linking */
+		if((self->flag & FILE_LINK)==0) {
+			Library *lib= BLI_findstring(&G.main->library, self->abspath, offsetof(Library, name));
+			if(lib)	all_local(lib, 1);
+			else	BLI_assert(!"cant find name of just added library!");
+		}
+	}
+
+	flag_all_listbases_ids(LIB_PRE_EXISTING, 0);
+
+	self->blo_handle= NULL;
+
+	Py_RETURN_NONE;
+}
+
+int bpy_lib_init(PyObject *mod_par)
+{
+	static PyMethodDef load_meth= {"load", (PyCFunction)bpy_lib_load, METH_STATIC|METH_VARARGS|METH_KEYWORDS};
+	PyModule_AddObject(mod_par, "_library_load", PyCFunction_New(&load_meth, NULL));
+
+	if(PyType_Ready(&bpy_lib_Type) < 0)
+		return -1;
+
+	return 0;
+}
diff --git a/source/blender/windowmanager/intern/wm_operators.c b/source/blender/windowmanager/intern/wm_operators.c
index 6ca7de943cf..27276e2aaac 100644
--- a/source/blender/windowmanager/intern/wm_operators.c
+++ b/source/blender/windowmanager/intern/wm_operators.c
@@ -1488,21 +1488,6 @@ static short wm_link_append_flag(wmOperator *op)
 	return flag;
 }
 
-static void wm_link_make_library_local(Main *main, const char *libname)
-{
-	Library *lib;
-
-	/* and now find the latest append lib file */
-	for(lib= main->library.first; lib; lib=lib->id.next)
-		if(BLI_streq(libname, lib->filepath))
-			break;
-	
-	/* make local */
-	if(lib) {
-		all_local(lib, 1);
-	}
-}
-
 static int wm_link_append_exec(bContext *C, wmOperator *op)
 {
 	Main *bmain= CTX_data_main(C);
@@ -1600,8 +1585,11 @@ static int wm_link_append_exec(bContext *C, wmOperator *op)
 	recalc_all_library_objects(bmain);
 
 	/* append, rather than linking */
-	if((flag & FILE_LINK)==0)
-		wm_link_make_library_local(bmain, libname);
+	if((flag & FILE_LINK)==0) {
+		Library *lib= BLI_findstring(&bmain->library, libname, offsetof(Library, filepath));
+		if(lib)	all_local(lib, 1);
+		else	BLI_assert(!"cant find name of just added library!");
+	}
 
 	/* important we unset, otherwise these object wont
 	 * link into other scenes from this blend file */