Merge pull request #4641 from reyoung/feature/add_persistable_in_var_desc

Init Python API

python/paddle/v2/framework/graph.py

+import paddle.v2.framework.core as core
+import collections
+
+__all__ = ['Block', 'Variable', 'Program', 'Operator']
+
+
+class Variable(object):
+    def __init__(self, block, name=None, shape=None, dtype=None,
+                 lod_level=None):
+        self.block = block
+
+        if name is None:
+            name = Variable._unique_var_name_()
+        self.proto = self.block.proto.new_var(name)
+
+        if shape is not None:
+            self.proto.set_shape(shape)
+
+        if dtype is not None:
+            # TODO(yuyang18): Convert dtype from numpy.dtype
+            self.proto.set_data_type(dtype)
+
+        if lod_level is not None:
+            # TODO(yuyang18): set_lod_level is not defined.
+            self.proto.set_lod_level(lod_level)
+
+        self.block.vars[name] = self
+        self.op = None
+
+    # TODO(yuyang18): Get methods
+
+    @staticmethod
+    def _unique_var_name_():
+        uid = core.unique_integer()  # unique during whole process.
+        return "_generated_var_%d" % uid
+
+
+class Operator(object):
+    def __init__(self,
+                 block,
+                 proto,
+                 type=None,
+                 inputs=None,
+                 outputs=None,
+                 attrs=None):
+        self.block = block
+        self.proto = proto
+        if type is not None:
+            # TODO.
+            pass
+        if inputs is not None:
+            # TODO
+            pass
+        if outputs is not None:
+            # TODO
+            pass
+        if attrs is not None:
+            # TODO
+            pass
+
+        # TODO: Getters
+
+
+class Block(object):
+    def __init__(self, program, idx):
+        self.proto = program.proto.block(idx)
+        self.vars = dict()  # var_name --> var
+        self.ops = collections.deque()  # operator list
+        self.program = program
+
+    @property
+    def parent_idx(self):
+        return self.proto.parent
+
+    @property
+    def idx(self):
+        return self.proto.id
+
+    def create_var(self, *args, **kwargs):
+        return Variable(self, *args, **kwargs)
+
+    def append_op(self, *args, **kwargs):
+        op_proto = self.proto.append_op()
+        op = Operator(self, op_proto, *args, **kwargs)
+        self.ops.append(op)
+        return op
+
+    def prepend_op(self, *args, **kwargs):
+        op_proto = self.proto.prepend_op()
+        op = Operator(self, op_proto, *args, **kwargs)
+        self.ops.appendleft(op)
+        return op
+
+
+class Program(object):
+    @classmethod
+    def instance(cls):
+        # From https://stackoverflow.com/questions/8212053
+        # Making Program as a Singleton class.
+        if not hasattr(cls, '_instance'):
+            cls._instance = cls()
+        return cls._instance
+
+    def __init__(self):
+        assert not hasattr(self.__class__,
+                           '_instance'), 'Do not call constructor directly!'
+        self.proto = core.ProgramDesc.instance()
+        self.blocks = [Block(self, 0)]
+        self.current_block_idx = 0
+
+    def global_block(self):
+        return self.blocks[0]
+
+    def current_block(self):
+        return self.blocks[self.current_block_idx]
+
+    def create_block(self):
+        new_block_idx = len(self.blocks)
+        self.proto.append_block(self.current_block().proto)
+        self.current_block_idx = new_block_idx
+        self.blocks.append(Block(self, self.current_block_idx))
+        return self.current_block()
+
+    def rollback(self):
+        self.current_block_idx = self.current_block().parent_idx
+
+
+# program is a global instance.
+g_program = Program.instance()

python/paddle/v2/framework/tests/test_program.py

+import unittest
+from paddle.v2.framework.graph import g_program
+
+
+class TestProgram(unittest.TestCase):
+    def test_program(self):
+        b = g_program.current_block()
+        self.assertEqual(-1, b.parent_idx)
+        self.assertEqual(0, b.idx)
+
+        b = g_program.create_block()
+        self.assertEqual(1, b.idx)
+        self.assertEqual(0, b.parent_idx)
+
+        b = g_program.create_block()
+        self.assertEqual(2, b.idx)
+        self.assertEqual(1, b.parent_idx)
+
+        g_program.rollback()
+
+        b = g_program.current_block()
+        self.assertEqual(1, b.idx)
+        self.assertEqual(0, b.parent_idx)
+
+        b = g_program.create_block()
+        self.assertEqual(3, b.idx)
+        self.assertEqual(1, b.parent_idx)
+
+        g_program.rollback()
+        b = g_program.current_block()
+        self.assertEqual(1, b.idx)
+        self.assertEqual(0, b.parent_idx)
+
+
+if __name__ == '__main__':
+    unittest.main()