Errors and other stuff

slow/__init__.py

@@ -1,11 +1,19 @@
-from .slow import JSONAPI, App, Headers, HTTPResponse, JSONResponse, Request, render
+from . import responses
+from .slow import (
+    JSONAPI,
+    App,
+    Headers,
+    Request,
+    redirect,
+    render,
+)
 
 __all__ = [
     "JSONAPI",
     "App",
-    "HTTPResponse",
-    "JSONResponse",
     "render",
     "Request",
     "Headers",
+    "redirect",
+    "responses",
 ]

slow/_errors.py

@@ -0,0 +1,38 @@
+import inspect
+
+
+def error_not_async(func):
+    if not inspect.iscoroutinefunction(func):
+        lines, start = inspect.getsourcelines(func)
+
+        fdef_index = 0
+        while fdef_index < len(lines) and not lines[fdef_index].strip().startswith(
+            "def"
+        ):
+            fdef_index += 1
+
+        if fdef_index < len(lines):
+            line_num = start + fdef_index
+
+            fdef_content = lines[fdef_index].strip()
+
+            ERROR_HEADER = "\033[1m\033[91m[FATAL_EXECUTION_ERROR]: Non-Asynchronous Route Detected\033[0m"
+
+            ERROR_BODY = (
+                f"\n"
+                f'--> File "{inspect.getsourcefile(func)}", line {line_num}, in {func.__name__}\n\n'
+                f"\033[1m[CONSTRAINT_VIOLATION]\033[0m\n"
+                f"  Synchronous function used where an async coroutine was required.\n"
+                f"  \033[93mCode Traceback:\033[0m\n"
+                f"  {line_num}: \033[93m{fdef_content}\033[0m\n\n"
+                f"\033[1m[SUGGESTED_PATCH]\033[0m\n"
+                f"  Apply the 'async' keyword to the function signature:\n"
+                f"  {line_num}: \033[92masync {fdef_content}\033[0m"
+            )
+
+            raise RuntimeError(ERROR_HEADER + ERROR_BODY)
+
+        else:
+            raise RuntimeError(
+                "\033[1m\033[91m[FATAL_EXECUTION_ERROR]: Non-Asynchronous Route Detected\033[0m"
+            )

slow/responses.py

@@ -0,0 +1,54 @@
+import http.client
+import json
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from .slow import App
+
+
+class Response:
+    status: int
+    headers: list[str]
+    body: bytes
+
+    def __init__(self, status: int, headers: list[str], body: bytes):
+        self.status = status
+        self.headers = headers
+        self.body = body
+        self.no_header = False
+
+    def header(self, app: "App") -> bytes:
+        header = f"HTTP/1.1 {self.status} {http.client.responses.get(self.status, 'Unkown Status Code')}\r\n"
+        header += f"Content-Length: {len(self.body)}\r\n"
+        for h in self.headers:
+            header += h + "\r\n"
+
+        header += "\r\n"
+
+        return header.encode(encoding="utf-8")
+
+    def render(self, app: "App") -> bytes:
+        if self.no_header:
+            return self.header(app)
+        return self.header(app) + self.body
+
+
+def HTTPResponse(
+    content: str | bytes,
+    status=200,
+    content_type="text/plain; charset=utf-8",
+    headers=[],
+) -> Response:
+    if isinstance(content, str):
+        content_bytes = content.encode(encoding="utf-8")
+    else:
+        content_bytes = content
+    return Response(
+        status, [f"Content-Type: {content_type}", *headers], body=content_bytes
+    )
+
+
+def JSONResponse(d: dict, status=200) -> Response:
+    return HTTPResponse(
+        json.dumps(d), status=status, content_type="text/json; charset=utf-8"
+    )

slow/slow.py

@@ -1,23 +1,26 @@
 import asyncio
-import http.client
 import json
 import re
 import urllib.parse
+from json.decoder import JSONDecodeError
 from pathlib import Path
 from typing import Any, Awaitable, Callable, Optional
 
+from . import _errors
+from .responses import HTTPResponse, JSONResponse, Response
+
 PR = re.compile(r"\<([a-zA-Z_][a-zA-Z0-9_]*)\>")
 
 
 class CORS:
-    Origins: list[str]
-    Methods: list[str]
+    Origins: set[str]
+    Methods: set[str]
     Disabled: bool
 
     def __init__(self):
         self.Disabled = False
-        self.Origins = []
-        self.Methods = ["GET", "POST", "PUT", "DELETE", "PATCH", "HEAD"]
+        self.Origins: set[str] = {}
+        self.Methods: set[str] = {"GET", "POST", "PUT", "DELETE", "PATCH", "HEAD"}
 
 
 class Headers:
@@ -38,14 +41,11 @@ class Headers:
 
 
 class Request:
-    def __init__(
-        self, method: str, path: str, headers: Headers, body: bytes, app: "App"
-    ):
+    def __init__(self, method: str, path: str, headers: Headers, body: bytes):
         self.method = method
         self.path = path
         self.headers = headers
         self.body = body
-        self.app = app
 
     def __str__(self):
         return str(
@@ -57,25 +57,33 @@ class Request:
             }
         )
 
+    def json(self) -> dict | None:
+        try:
+            return json.loads(self.body)
+        except JSONDecodeError:
+            return None
+
 
 async def _default_404_route(request: Request):
-    return "HTTP/1.1 404 Not Found\r\nContent-Type: text/html\r\n\r\n404 Not Found contact admin".encode(
-        encoding="utf-8"
-    )
+    return HTTPResponse("404 Not Found", status=404)
 
 
 async def _default_405_route(request: Request):
-    return "HTTP/1.1 405 Method Not Allowed\r\nContent-Type: text/html\r\n\r\n405 Method Not Allowed".encode(
-        encoding="utf-8"
-    )
+    return HTTPResponse(b"", status=405)
 
 
 class App:
     def __init__(self):
         self.routes: dict[
-            re.Pattern[str], dict[str, Callable[[Request, ...], Awaitable[bytes]]]
+            re.Pattern[str],
+            dict[
+                str,
+                Callable[[Request, ...], Awaitable[Response | None]],
+            ],
         ] = {}
-        self.error_routes: dict[int, Callable[[Request, ...], Awaitable[bytes]]] = {
+        self.error_routes: dict[
+            int, Callable[[Request, ...], Awaitable[Response | None]]
+        ] = {
             404: _default_404_route,
             405: _default_405_route,
         }
@@ -90,10 +98,14 @@ class App:
         return re.compile(re_temp)
 
     def _serve(
-        self, path: str, method: str, func: Callable[[Request, ...], Awaitable[bytes]]
+        self,
+        path: str,
+        method: str,
+        func: Callable[[Request, ...], Awaitable[Response | None]],
     ):
-        if method not in ["GET", "POST", "PUT", "DELETE"]:
+        if method not in ["GET", "POST", "PUT", "DELETE", "PATCH", "HEAD"]:
             raise RuntimeError(f'Invalid method "{method}".')
+        _errors.error_not_async(func)
         pat = self._pattern_to_regex(path)
         if pat not in self.routes:
             self.routes[pat] = {}
@@ -104,8 +116,16 @@ class App:
     def GET(self, path: str):
         """Decorator to register a GET HTTP route."""
 
-        def decorator(func: Callable[[Request, ...], Awaitable[bytes]]):
+        def decorator(func: Callable[[Request, ...], Awaitable[Response | None]]):
             self._serve(path, "GET", func)
+
+            async def wrapper(*args, **kwargs):
+                res = await func(*args, **kwargs)
+                if isinstance(res, Response):
+                    res.no_header = True
+                return res
+
+            self._serve(path, "HEAD", wrapper)
             return func
 
         return decorator
@@ -113,7 +133,7 @@ class App:
     def POST(self, path: str):
         """Decorator to register a POST HTTP route."""
 
-        def decorator(func: Callable[[Request, ...], Awaitable[bytes]]):
+        def decorator(func: Callable[[Request, ...], Awaitable[Response | None]]):
             self._serve(path, "POST", func)
             return func
 
@@ -122,14 +142,14 @@ class App:
     def PUT(self, path: str):
         """Decorator to register a PUT HTTP route."""
 
-        def decorator(func: Callable[[Request, ...], Awaitable[bytes]]):
+        def decorator(func: Callable[[Request, ...], Awaitable[Response | None]]):
             self._serve(path, "PUT", func)
             return func
 
     def DELETE(self, path: str):
         """Decorator to register a DELETE HTTP route."""
 
-        def decorator(func: Callable[[Request, ...], Awaitable[bytes]]):
+        def decorator(func: Callable[[Request, ...], Awaitable[Response | None]]):
             self._serve(path, "DELETE", func)
             return func
 
@@ -138,7 +158,7 @@ class App:
     def PATCH(self, path: str):
         """Decorator to register a PATCH HTTP route."""
 
-        def decorator(func: Callable[[Request, ...], Awaitable[bytes]]):
+        def decorator(func: Callable[[Request, ...], Awaitable[Response | None]]):
             self._serve(path, "PATCH", func)
             return func
 
@@ -147,7 +167,7 @@ class App:
     def HEAD(self, path: str):
         """Decorator to register a HEAD HTTP route."""
 
-        def decorator(func: Callable[[Request, ...], Awaitable[bytes]]):
+        def decorator(func: Callable[[Request, ...], Awaitable[Response | None]]):
             self._serve(path, "HEAD", func)
             return func
 
@@ -162,16 +182,22 @@ class App:
 
         return decorator
 
-    def resolve(self, path, method) -> tuple[Callable[..., Awaitable[bytes]], dict]:
+    def resolve(self, path, method) -> tuple[Callable[..., Awaitable[Response]], dict]:
         for pattern, route in self.routes.items():
             if m := pattern.fullmatch(path):
-                if method not in route:
+                if method not in route or method == "websocket":
                     return self.error_routes[405], {}
                 return route[method], {
                     k: urllib.parse.unquote(v) for k, v in m.groupdict().items()
-                }
+                }  # ty:ignore[invalid-return-type]
         return self.error_routes[404], {}
 
+    def methods(self, path) -> set[str]:
+        for pattern, route in self.routes.items():
+            if pattern.fullmatch(path):
+                return set(route.keys() - {"websocket"})
+        return set()
+
     async def handle_client(
         self, reader: asyncio.StreamReader, writer: asyncio.StreamWriter
     ):
@@ -182,6 +208,12 @@ class App:
             if not request_line:
                 return
 
+            if not request_line.decode(encoding="utf-8").startswith(
+                ("GET", "POST", "PUT", "HEAD", "DELETE", "PATCH", "OPTIONS")
+            ):
+                # Probably WebSocket
+                pass
+
             # Parse request line
             parts = request_line.decode(encoding="utf-8").strip().split()
             if len(parts) < 3:
@@ -204,45 +236,70 @@ class App:
             content_length = int(headers.get("Content-Length", 0))
             body = await reader.read(content_length) if content_length else b""
 
-            if method == "OPTIONS":
+            if (
+                method == "OPTIONS"
+            ):  # FIXME Should handle responding with available methods as well
                 if "origin" in headers and headers.get("origin") in self.CORS.Origins:
                     origin = headers.get("origin")
-                    response = "HTTP/1.1 200 OK\r\n"
-                    response += "Content-Type: text/plain\r\n"
-                    response += "Content-Length: 0\r\n"
-                    response += f"Access-Control-Allow-Origin: {origin}\r\n"
-                    response += f"Access-Control-Allow-Methods: {','.join(self.CORS.Methods)}\r\n"
-                    response += "Access-Control-Allow-Headers: Content-Type,Authorization\r\n"  # CORS
-                    response += "Vary: Origin\r\n"
-                    response += "\r\n"
+                    head = [
+                        "Content-Type: text/plain",
+                        "Content-Length: 0",
+                        f"Access-Control-Allow-Origin: {origin}",
+                        f"Access-Control-Allow-Methods: {','.join(self.CORS.Methods)}",
+                        "Access-Control-Allow-Headers: Content-Type,Authorization",  # CORS
+                        "Vary: Origin",
+                    ]
 
-                    writer.write(response.encode(encoding="utf-8"))
+                    writer.write(Response(200, head, b"").render(self))
 
                     await writer.drain()
 
                 else:
-                    response = "HTTP/1.1 403 Forbidden\r\n"
-                    response += "Content-Length: 0\r\n"
-                    response += "Vary: Origin\r\n"
-                    response += "\r\n"
-
-                    writer.write(response.encode(encoding="utf-8"))
+                    writer.write(Response(403, ["Vary: Origin"], b"").render(self))
 
                     await writer.drain()
 
             else:
                 route, kwargs = self.resolve(path, method)
 
-                response = await route(
+                if (
+                    method == "GET"
+                    and "connection" in headers
+                    and headers.get("connection") == "Upgrade"
+                    and "upgrade" in headers
+                ):
+                    # Upgrade
+                    return Response(
+                        status=426, headers=["Connection: close"], body=b""
+                    ).render(self)
+
+                response: Response = await route(
                     request=Request(
-                        method=method, path=path, headers=headers, body=body, app=self
+                        method=method, path=path, headers=headers, body=body
                     ),
                     **kwargs,
                 )
-                writer.write(response)
+                response.headers.append("Vary: Origin")
+                if (
+                    "origin" in headers
+                    and self.CORS.Disabled
+                    and headers.get("origin") in self.CORS.Origins
+                ):  # CORS
+                    response.headers.append(
+                        f"Access-Control-Allow-Origin: {headers.get('origin')}"
+                    )
+                    response.headers.append(
+                        f"Access-Control-Allow-Methods: {','.join(self.CORS.Methods & self.methods(path))}"
+                    )
+                    response.headers.append(
+                        "Access-Control-Allow-Headers: Content-Type,Authorization\r\n"
+                    )
+
+                writer.write(response.render(self))
 
                 await writer.drain()
         except Exception as e:
+            raise e
             print(f"Internal Server Error: {e}")
         finally:
             writer.close()
@@ -258,51 +315,26 @@ class App:
             await server.serve_forever()
 
 
-def HTTPResponse(
-    request: Request,
-    content: str,
-    status=200,
-    content_type="text/plain; charset=utf-8",
-    headers=[],
-) -> bytes:
-    content_bytes = content.encode(encoding="utf-8")
-    head: str = f"HTTP/1.1 {status} {http.client.responses.get(status, 'Unkown Status Code')}\r\nContent-Type: {content_type}\r\nContent-Length: {len(content_bytes)}\r\n"
-    if (
-        "origin" in request.headers
-        and not request.app.CORS.Disabled
-        and request.headers.get("origin") in request.app.CORS.Origins
-    ):
-        head += (
-            f"Access-Control-Allow-Origin: {request.headers.get('origin')}\r\n"  # CORS
-        )
-        head += f"Access-Control-Allow-Methods: {','.join(request.app.CORS.Methods)}\r\n"  # CORS
-        head += "Access-Control-Allow-Headers: Content-Type,Authorization\r\n"  # CORS
-    head += "Vary: Origin\r\n"
-    head += "\r\n".join(headers) + ("\r\n" if len(headers) > 0 else "")
-    head += "\r\n"
-    return head.encode(encoding="utf-8") + content_bytes
-
-
 _value_pattern = re.compile(r"\{\{\s*([a-zA-Z_][a-zA-Z_0-9]*)\s*\}\}")
 
 
-def render(request: Request, file: str | Path, variables: dict[str, Any] = {}) -> bytes:
+def render(
+    file: str | Path, variables: dict[str, Any] = {}
+) -> Response:  # TODO Move to another module
     if isinstance(file, str):
         file = Path(file)
     content: str = file.read_text(encoding="utf-8")
     for m in _value_pattern.findall(content):
         if m in variables:
             content = re.sub(r"\{\{\s*" + m + r"\s*\}\}", variables[m], content)
-    return HTTPResponse(request, content, content_type="text/html; charset=utf-8")
+    return HTTPResponse(content, content_type="text/html; charset=utf-8")
 
 
-def JSONResponse(request: Request, d: dict, status=200) -> bytes:
-    return HTTPResponse(
-        request, json.dumps(d), status=status, content_type="text/json; charset=utf-8"
-    )
+def redirect(location: str):  # TODO Move to another module
+    return Response(307, ["Location: {location}"], b"")
 
 
-def JSONAPI(func):
+def JSONAPI(func):  # TODO Move to another module
     async def wrapper(*args, **kwargs):
         result = await func(*args, **kwargs)
         if not isinstance(result, dict):
@@ -314,6 +346,6 @@ def JSONAPI(func):
             ):
                 return JSONResponse(result[1], result[0])
             raise RuntimeError("Return value of JSONAPI route is not a dictionary")
-        return JSONResponse(args[0], result)
+        return JSONResponse(result)
 
     return wrapper