init

.gitignore

@@ -93,3 +93,18 @@ ENV/
 .idea/
 
 .vscode/
+
+# example
+Werkzeug-0.15.5.dist-info
+werkzeug
+MarkupSafe-1.1.1.dist-info
+markupsafe
+Jinja2-2.10.1.dist-info
+jinja2
+itsdangerous-1.1.0.dist-info
+itsdangerous
+Flask-1.1.1.dist-info
+flask
+Click-7.0.dist-info
+click
+bin

README.md

@@ -1 +1,48 @@
 # aligi
+
+为无服务函数计算作为阿里云 API 后端运行提供转析。
+
+## 为什么会有这个库？
+
+使用 Flask，Django 等支持标准 WSGI 协议的 Web 框架创建无服务函数时，使用HTTP触发器才能让它们正常运行。
+
+但如果想使用无服务函数作为阿里云 API 网关的后端时，则无法直接使用这些函数，只能通过网络调用，这显然是不够高效、并且费钱的。
+
+## 如何安装
+
+在项目根目录下执行
+
+```
+pip install -t . aligi
+```
+
+## 如何使用
+
+以下为一个最小的 Flask 样例
+
+```python
+import json
+
+from flask import Flask
+from aligi.wsgi import WSGI
+from aligi.types import FCContext
+
+app = Flask(__name__)
+
+
+@app.route('/')
+def hello_world():
+    return 'Hello, World!'
+
+
+def handler(event: str, context: FCContext):
+    """阿里云无服务函数的入口"""
+    wsgi = WSGI(event, context)
+    wsgi.mount(app)
+    return wsgi.get_response()
+```
+
+其中`app`可以是任意一个标准 WSGI Application。
+
+在 Django 项目中，它一般在项目的`wsgi.py`里。
+

aligi/__version__.py

@@ -1,3 +1,3 @@
-VERSION = (0, 0, 0)
+VERSION = (0, 0, 1)
 
 __version__ = '.'.join(map(str, VERSION))

aligi/core.py

@@ -4,12 +4,17 @@
 from aligi import types
 
 
-class Request:
+class HTTPRequest:
+    """解析阿里云API网关传递的数据"""
 
     def __init__(self, event: str, context: types.FCContext):
         self.context = context
         self.event = json.loads(event)
-        self.header = self.event['headers']
+        self._header = {
+            "CONTENT-TYPE": "text/plain",
+            "CONTENT-LENGTH": 0,
+        }
+        self._header.update({k.upper(): v for k, v in self.event['headers'].items()})
 
     @property
     def path(self) -> str:
@@ -23,10 +28,6 @@ def method(self) -> str:
     def header(self) -> dict:
         return self._header
 
-    @header.setter
-    def set_header(self, value: dict) -> None:
-        self._header = {k.upper(): v for k, v in value.items()}
-
     @property
     def query(self) -> dict:
         return self.event['queryParameters']

aligi/types.py

@@ -81,4 +81,14 @@ def __init__(
         self.account_id = account_id
 
 
-WSGIApp = typing.Callable[typing.Dict, typing.Callable(str, typing.Iterable(typing.Tuple(str, str)))]
+WSGIApp = typing.Callable[
+    [
+        typing.Dict,
+        typing.Callable[
+            [
+                str,
+                typing.Iterable[typing.Tuple[str, str]]
+            ], None
+        ]
+    ], typing.Iterable
+]

aligi/wsgi.py

@@ -1,24 +1,54 @@
+import io
 import json
 import typing
 import base64
 
 from aligi.types import FCContext, WSGIApp
-from aligi.core import Request
+from aligi.core import HTTPRequest
 
 
 class BodyTypeError(Exception):
     pass
 
 
+class ErrorWriter:
+    """处理错误日志则继承于此"""
+
+    def flush(self) -> None:
+        pass
+
+    def write(self, msg: str) -> None:
+        pass
+
+    def writelines(self, seq: str) -> None:
+        pass
+
+
 class WSGI:
 
     def __init__(self, event: str, context: FCContext):
-        self.request = Request(event, context)
-        self.set_environ()
-        self.data = {}
-
-    def set_environ(self):
+        self.request = HTTPRequest(event, context)
         self.environ = {
+            "wsgi.version": (1, 0),
+            "wsgi.url_scheme": "http",
+            "wsgi.input": io.BytesIO(self.request.body),
+            "wsgi.errors": self.errors,
+            "wsgi.multithread": False,
+            "wsgi.multiprocess": False,
+            "wsgi.run_once": True,
+        }
+        self.update_environ()
+        self.raw_data = {}
+
+    @property
+    def errors(self) -> ErrorWriter:
+        """
+        如果需要自定义处理错误日志, 则需要覆盖此属性
+        """
+        return ErrorWriter()
+
+    def update_environ(self) -> None:
+        self.environ.update({
             "REQUEST_METHOD": self.request.method,
             "SCRIPT_NAME": "",
             "PATH_INFO": self.request.path,
@@ -28,31 +58,34 @@ def set_environ(self):
             "SERVER_NAME": "127.0.0.1",
             "SERVER_PORT": "80",
             "SERVER_PROTOCOL": "HTTP/1.1",
-        }
-        self.environ.update({f"HTTP_{k}": v for k, v in self.request.header})
+        })
+        self.environ.update({f"HTTP_{k}": v for k, v in self.request.header.items()})
 
-    def start_response(self, status: str, headers: typing.Iterable(typing.Tuple(str, str)), exc_info: str = ""):
-        self.data.update({
+    def start_response(
+        self,
+        status: str,
+        headers: typing.Iterable[typing.Tuple[str, str]],
+        exc_info: str = ""
+    ) -> None:
+        """
+        WSGI 标准 start_response, 传递状态码与HTTP头部
+        """
+        self.raw_data.update({
             "statusCode": int(status[:3]),
             "headers": {
                 header[0]: header[1] for header in headers
             },
         })
 
-    def mount(self, wsgi: WSGIApp):
-        body = wsgi(self.environ, self.start_response)
-        if isinstance(body, bytes):
-            self.data.update({
-                "body": base64.b64encode(b"".join(body)),
-                "isBase64Encoded": True
-            })
-        elif isinstance(body, str):
-            self.data.update({
-                "body": body,
-                "isBase64Encoded": False
-            })
-        else:
-            raise BodyTypeError(f"body type: {type(body)}")
-
-    def get_response(self):
-        return json.dumps(self.data)
+    def mount(self, wsgi: WSGIApp) -> None:
+        """挂载并调用标准 WSGI Application"""
+        body: typing.Iterable = wsgi(self.environ, self.start_response)
+        body = b"".join(body)
+        self.raw_data.update({
+            "body": base64.b64encode(body).decode("utf8"),
+            "isBase64Encoded": True
+        })
+
+    def get_response(self) -> str:
+        """返回 JSON 字符串的结果"""
+        return json.dumps(self.raw_data)

example.py

@@ -0,0 +1,34 @@
+import json
+
+from flask import Flask
+from aligi.wsgi import WSGI
+from aligi.types import FCContext
+
+app = Flask(__name__)
+
+
+@app.route('/')
+def hello_world():
+    return 'Hello, World!'
+
+
+def handler(event: str, context: FCContext):
+    """阿里云无服务函数的入口"""
+    wsgi = WSGI(event, context)
+    wsgi.mount(app)
+    return wsgi.get_response()
+
+
+if __name__ == "__main__":
+    print(handler(json.dumps({
+        "path": "/",
+        "httpMethod": "GET",
+        "headers": {
+            "Content-Length": 0,
+            "Content-Type": "text/plain"
+        },
+        "queryParameters": {},
+        "pathParameters": {},
+        "body": "",
+        "isBase64Encoded": False
+    }), None))