ast and inspect

Change-Id: I24204e8e861d4b964d41ca283fc5e95ce8bc4c7b

Author: yangwenqiang.ywq

README.md

@@ -285,6 +285,10 @@ python的强大之处有很大的一方面在于它有各种各样非常强大
 
 ## [weakref](content/weakref.md)
 
+## [ast](content/ast.md)
+
+## [inspect](content/inspect.md)
+
 ## [tools](content/tools.md)
 
 ## [Other_thing](content/other_thing.md)

code/ast_back.py

@@ -0,0 +1,29 @@
+# coding=utf-8
+
+import ast
+import unparse
+
+code = """
+def add(a, b):
+	return a + b
+
+print add(1, 2)
+"""
+
+
+class CrazyTransformer(ast.NodeTransformer):
+
+    def visit_BinOp(self, node):
+        node.op = ast.Mult()
+        return node
+
+
+def back():
+	module = ast.parse(code)
+	transformer = CrazyTransformer()
+	multi = transformer.visit(module)
+	unparse.Unparser(multi)
+
+
+if __name__ == '__main__':
+	back()

code/ast_change.py

@@ -0,0 +1,32 @@
+# coding=utf-8
+
+import ast
+
+
+code = """
+def add(a, b):
+	return a + b
+
+print add(1, 2)
+"""
+
+
+class CrazyTransformer(ast.NodeTransformer):
+
+    def visit_BinOp(self, node):
+        print node.__dict__
+        node.op = ast.Mult()
+        print node.__dict__
+        return node
+
+
+def main():
+	module = ast.parse(code)
+	exec compile(module, '<string>', 'exec')
+	transformer = CrazyTransformer()
+	multi = transformer.visit(module)
+	exec compile(multi, '<string>', 'exec')
+
+
+if __name__ == '__main__':
+	main()

code/ast_demo.py

@@ -0,0 +1,14 @@
+# coding=utf-8
+
+import ast
+
+code = """
+def add(a, b):
+	return a + b
+
+add(1, 2)
+"""
+
+print "hello world"
+print ast.parse(code)
+print ast.dump(ast.parse(code))

code/ast_other.py

@@ -0,0 +1,25 @@
+# coding=utf-8
+
+import ast
+import codegen
+import astunparse
+import astor
+
+
+code = """
+data = {
+	"key": "value",
+	"list": [1,2,3]
+}
+
+def add(a, b):
+	return a + b
+
+print add(1, 2)
+"""
+
+module = ast.parse(code)
+
+print codegen.to_source(module)
+print astunparse.unparse(module)
+print astor.to_source(module)

code/bunch.md

@@ -89,3 +89,17 @@ if __name__ == '__main__':
 
 基本上是一个思路，然后再加了一些捕获异常和类型转换，更容易的转换为其他的数据结构。
 
+
+还可以这样
+
+```
+class Namespace(dict):
+    def __getattr__(self, name):
+        try:
+            return self[name]
+        except KeyError:
+            raise AttributeError(name)
+
+    def __setattr__(self, name, value):
+        self[name] = value
+```

code/example.py

@@ -0,0 +1,34 @@
+# coding=utf-8
+# 只能这里么？
+
+
+# fist two line comment
+# 再来一行注释
+
+functions = {}
+
+def add(a, b):
+	return a + b
+
+
+class A(object):
+	"""
+	A class
+	"""
+	def ___init__(self, name):
+		self.name = name
+
+
+class B(A):
+	
+	def hello(self, word=None):
+		"""
+		greeting
+		"""
+		if not word:
+			word = self.name
+		print "hello {}".format(word)
+
+
+a = A()
+b = B()

code/inspect_args.py

@@ -0,0 +1,17 @@
+# coding=utf-8
+
+import inspect
+import example
+
+
+def main(a=1):
+    print inspect.getargvalues(inspect.currentframe())
+
+
+if __name__ == '__main__':
+    main()
+    print inspect.getargspec(example.add)
+    print inspect.formatargspec(inspect.getargspec(example.add))
+    print inspect.getargspec(example.B.hello)
+    print inspect.getcallargs(example.add, 1, 2)
+    print inspect.getcallargs(example.B.hello, self=None, word="world")

code/inspect_class_and_instant.py

@@ -0,0 +1,27 @@
+# coding=utf-8
+
+import inspect
+import example
+
+
+def detect_class():
+    print("A:")
+    for name, data in inspect.getmembers(example.A):
+        print('{} : {}'.format(name, data))
+
+
+def detect_method():
+    print("A:")
+    for name, data in inspect.getmembers(example.A, inspect.ismethod):
+        print('{} : {}'.format(name, data))
+    print("B:")
+    for name, data in inspect.getmembers(example.B, inspect.ismethod):
+        print('{} : {}'.format(name, data))
+    print("a:")
+    for name, data in inspect.getmembers(example.a, inspect.ismethod):
+        print('{} : {}'.format(name, data))
+
+
+if __name__ == '__main__':
+    detect_class()
+    detect_method()

code/inspect_demo.py

@@ -0,0 +1,44 @@
+# coding=utf-8
+
+import inspect
+
+import example
+
+
+def detect_all():
+    for name, data in inspect.getmembers(example):
+        if name.startswith('__'):
+            continue
+        print('{} : {}'.format(name, data))
+
+
+def detect_class():
+    for name, data in inspect.getmembers(example, inspect.isclass):
+        if name.startswith('__'):
+            continue
+        print('{} : {}'.format(name, data))
+
+
+def detect_code():
+    for name, data in inspect.getmembers(example, inspect.iscode):
+        if name.startswith('__'):
+            continue
+        print('{} : {}'.format(name, data))
+
+
+def detect_function():
+    for name, data in inspect.getmembers(example, inspect.isfunction):
+        if name.startswith('__'):
+            continue
+        print('{} : {}'.format(name, data))
+
+
+if __name__ == '__main__':
+    print "all:"
+    detect_all()
+    print "class:"
+    detect_class()
+    print "function:"
+    detect_function()
+    print "code:"
+    detect_code()

code/inspect_detect.py

@@ -0,0 +1,17 @@
+# coding=utf-8
+
+import inspect
+import example
+
+if __name__ == '__main__':
+    print inspect.isbuiltin(apply)
+    print inspect.isbuiltin(lambda: None)
+    print inspect.isclass(type)
+    print inspect.isclass(1)
+    print inspect.iscode(example.add.func_code)
+    print inspect.iscode(example.B.hello.im_func.func_code)
+    print inspect.iscode("1+1")
+    print inspect.ismodule(inspect)
+    print inspect.isfunction(input)
+    print inspect.isgenerator(iter([]))
+    print inspect.isgenerator([])

code/inspect_source.py

@@ -0,0 +1,24 @@
+# coding=utf-8
+
+import inspect
+import example
+
+if __name__ == '__main__':
+
+    print inspect.getcomments(example)
+    print inspect.getdoc(example)
+    print inspect.getdoc(example.A)
+    print inspect.getdoc(example.B.hello)
+
+    print inspect.findsource(example.A)
+
+    print inspect.getabsfile(example.A)
+    print inspect.getfile(example.A)
+    print inspect.getsource(example)
+    print inspect.getsource(example.A)
+    print inspect.getsourcefile(example.A)
+    print inspect.getsourcelines(example.A)
+
+    print inspect.getmodule(example.A)
+    print inspect.getmoduleinfo("example.py")
+    print inspect.getmodulename("example.py")

code/inspect_stack.py

@@ -0,0 +1,35 @@
+# coding=utf-8
+
+import inspect
+
+
+def get_frame():
+    """
+    帧是当前的上下文，调用时的环境变量和数据
+    """
+    frame = inspect.currentframe()
+    print 'line {} of {}'.format(frame.f_lineno, frame.f_code.co_filename)
+    print 'locals: {}'.format(frame.f_locals)
+
+
+def get_stack():
+    """
+    栈是用来展示调用链路，每一层都是一个帧
+    """
+    for frame, filename, lineno, func, code_context, code_index in inspect.stack():
+        print('{}[{}]\n -> {}:{}'.format(
+            filename,
+            lineno,
+            func,
+            code_context[code_index].strip()
+        ))
+        print frame.f_locals
+
+
+if __name__ == '__main__':
+    frame = inspect.currentframe()
+    print 'line {} of {}'.format(frame.f_lineno, frame.f_code.co_filename)
+    print 'locals: {}'.format(frame.f_locals)
+
+    get_frame()
+    get_stack()

code/marshmallow_demo.py

@@ -14,12 +14,25 @@ class AlbumSchema(Schema):
 	title = fields.Str()
 	release_date = fields.Date()
 	artist = fields.Nested(ArtistSchema())
+	response = fields.Function(serialize=lambda x: "response data")
+	request = fields.Function(serialize=lambda x:x.a, deserialize=lambda x: "request data")
 
 
 bowie = dict(name='David Bowie', location=["Beijing", "Shanghai"])
-album = dict(artist=bowie, title="Hunky Dory", release_date=datetime.now())
+album = dict(artist=bowie, title="Hunky Dory", release_date=datetime.now(), request="...")
 
 schema = AlbumSchema()
-result = schema.dump(album)
-pprint(result, indent=2)
 
+# 将一个 object 转换成 dict , 属于 serialize 在 pack response 中
+# 在转换成 dict 的时候，会去取值，如果没有，就会返回 missing_, 然后再返回值里也不展示
+dump_result = schema.dump(album)
+pprint(dump_result, indent=2)
+print dump_result.data
+
+# 讲一个 dict 转换成 object, 属于 deserialize 在 request 里或者 转化里使用
+# 使用 load 的时候，原始数据中必须存在这个字段，如果原始字段不存在，则没有，如果没有 deserialize 函数，则返回原始值。
+load_result = schema.load(album)
+pprint(load_result, indent=2)
+print load_result.data
+
+# print schema.fields