Merge pull request #58 from michalpokusa/server-headers

Server headers, FormData, some docs improvements and fix for bug in ChunkedResponse

README.rst

@@ -27,7 +27,7 @@ HTTP Server for CircuitPython.
 - HTTP 1.1.
 - Serves files from a designated root.
 - Routing for serving computed responses from handlers.
-- Gives access to request headers, query parameters, body and client's address, the one from which the request came.
+- Gives access to request headers, query parameters, form data, body and client's address (the one from which the request came).
 - Supports chunked transfer encoding.
 - Supports URL parameters and wildcard URLs.
 - Supports HTTP Basic and Bearer Authentication on both server and route per level.

adafruit_httpserver/__init__.py

@@ -51,15 +51,21 @@
     CONNECT,
 )
 from .mime_types import MIMETypes
-from .request import Request
+from .request import QueryParams, FormData, Request
 from .response import (
     Response,
     FileResponse,
     ChunkedResponse,
     JSONResponse,
     Redirect,
 )
-from .server import Server
+from .server import (
+    Server,
+    NO_REQUEST,
+    CONNECTION_TIMED_OUT,
+    REQUEST_HANDLED_NO_RESPONSE,
+    REQUEST_HANDLED_RESPONSE_SENT,
+)
 from .status import (
     Status,
     OK_200,

adafruit_httpserver/authentication.py

@@ -41,6 +41,10 @@ def __str__(self) -> str:
 def check_authentication(request: Request, auths: List[Union[Basic, Bearer]]) -> bool:
     """
     Returns ``True`` if request is authorized by any of the authentications, ``False`` otherwise.
+
+    Example::
+
+        check_authentication(request, [Basic("username", "password")])
     """
 
     auth_header = request.headers.get("Authorization")
@@ -56,6 +60,10 @@ def require_authentication(request: Request, auths: List[Union[Basic, Bearer]])
     Checks if the request is authorized and raises ``AuthenticationError`` if not.
 
     If the error is not caught, the server will return ``401 Unauthorized``.
+
+    Example::
+
+        require_authentication(request, [Basic("username", "password")])
     """
 
     if not check_authentication(request, auths):

adafruit_httpserver/request.py

@@ -8,7 +8,7 @@
 """
 
 try:
-    from typing import Dict, Tuple, Union, TYPE_CHECKING
+    from typing import List, Dict, Tuple, Union, Any, TYPE_CHECKING
     from socket import socket
     from socketpool import SocketPool
 
@@ -22,6 +22,141 @@
 from .headers import Headers
 
 
+class _IFieldStorage:
+    """Interface with shared methods for QueryParams and FormData."""
+
+    _storage: Dict[str, List[Union[str, bytes]]]
+
+    def _add_field_value(self, field_name: str, value: Union[str, bytes]) -> None:
+        if field_name not in self._storage:
+            self._storage[field_name] = [value]
+        else:
+            self._storage[field_name].append(value)
+
+    def get(self, field_name: str, default: Any = None) -> Union[str, bytes, None]:
+        """Get the value of a field."""
+        return self._storage.get(field_name, [default])[0]
+
+    def get_list(self, field_name: str) -> List[Union[str, bytes]]:
+        """Get the list of values of a field."""
+        return self._storage.get(field_name, [])
+
+    @property
+    def fields(self):
+        """Returns a list of field names."""
+        return list(self._storage.keys())
+
+    def __getitem__(self, field_name: str):
+        return self.get(field_name)
+
+    def __iter__(self):
+        return iter(self._storage)
+
+    def __len__(self):
+        return len(self._storage)
+
+    def __contains__(self, key: str):
+        return key in self._storage
+
+    def __repr__(self) -> str:
+        return f"{self.__class__.__name__}({repr(self._storage)})"
+
+
+class QueryParams(_IFieldStorage):
+    """
+    Class for parsing and storing GET quer parameters requests.
+
+    Examples::
+
+        query_params = QueryParams(b"foo=bar&baz=qux&baz=quux")
+        # QueryParams({"foo": "bar", "baz": ["qux", "quux"]})
+
+        query_params.get("foo") # "bar"
+        query_params["foo"] # "bar"
+        query_params.get("non-existent-key") # None
+        query_params.get_list("baz") # ["qux", "quux"]
+        "unknown-key" in query_params # False
+        query_params.fields # ["foo", "baz"]
+    """
+
+    _storage: Dict[str, List[Union[str, bytes]]]
+
+    def __init__(self, query_string: str) -> None:
+        self._storage = {}
+
+        for query_param in query_string.split("&"):
+            if "=" in query_param:
+                key, value = query_param.split("=", 1)
+                self._add_field_value(key, value)
+            elif query_param:
+                self._add_field_value(query_param, "")
+
+
+class FormData(_IFieldStorage):
+    """
+    Class for parsing and storing form data from POST requests.
+
+    Supports ``application/x-www-form-urlencoded``, ``multipart/form-data`` and ``text/plain``
+    content types.
+
+    Examples::
+
+        form_data = FormData(b"foo=bar&baz=qux&baz=quuz", "application/x-www-form-urlencoded")
+        # or
+        form_data = FormData(b"foo=bar\\r\\nbaz=qux\\r\\nbaz=quux", "text/plain")
+        # FormData({"foo": "bar", "baz": "qux"})
+
+        form_data.get("foo") # "bar"
+        form_data["foo"] # "bar"
+        form_data.get("non-existent-key") # None
+        form_data.get_list("baz") # ["qux", "quux"]
+        "unknown-key" in form_data # False
+        form_data.fields # ["foo", "baz"]
+    """
+
+    _storage: Dict[str, List[Union[str, bytes]]]
+
+    def __init__(self, data: bytes, content_type: str) -> None:
+        self.content_type = content_type
+        self._storage = {}
+
+        if content_type.startswith("application/x-www-form-urlencoded"):
+            self._parse_x_www_form_urlencoded(data)
+
+        elif content_type.startswith("multipart/form-data"):
+            boundary = content_type.split("boundary=")[1]
+            self._parse_multipart_form_data(data, boundary)
+
+        elif content_type.startswith("text/plain"):
+            self._parse_text_plain(data)
+
+    def _parse_x_www_form_urlencoded(self, data: bytes) -> None:
+        decoded_data = data.decode()
+
+        for field_name, value in [
+            key_value.split("=", 1) for key_value in decoded_data.split("&")
+        ]:
+            self._add_field_value(field_name, value)
+
+    def _parse_multipart_form_data(self, data: bytes, boundary: str) -> None:
+        blocks = data.split(b"--" + boundary.encode())[1:-1]
+
+        for block in blocks:
+            disposition, content = block.split(b"\r\n\r\n", 1)
+            field_name = disposition.split(b'"', 2)[1].decode()
+            value = content[:-2]
+
+            self._add_field_value(field_name, value)
+
+    def _parse_text_plain(self, data: bytes) -> None:
+        lines = data.split(b"\r\n")[:-1]
+
+        for line in lines:
+            field_name, value = line.split(b"=", 1)
+
+            self._add_field_value(field_name.decode(), value.decode())
+
+
 class Request:
     """
     Incoming request, constructed from raw incoming bytes.
@@ -44,8 +179,7 @@ class Request:
 
     Example::
 
-            request.client_address
-            # ('192.168.137.1', 40684)
+        request.client_address  # ('192.168.137.1', 40684)
     """
 
     method: str
@@ -54,15 +188,17 @@ class Request:
     path: str
     """Path of the request, e.g. ``"/foo/bar"``."""
 
-    query_params: Dict[str, str]
+    query_params: QueryParams
     """
     Query/GET parameters in the request.
 
     Example::
 
-            request  = Request(raw_request=b"GET /?foo=bar HTTP/1.1...")
-            request.query_params
-            # {"foo": "bar"}
+        request  = Request(..., raw_request=b"GET /?foo=bar&baz=qux HTTP/1.1...")
+
+        request.query_params                  # QueryParams({"foo": "bar"})
+        request.query_params["foo"]           # "bar"
+        request.query_params.get_list("baz")  # ["qux"]
     """
 
     http_version: str
@@ -91,6 +227,7 @@ def __init__(
         self.connection = connection
         self.client_address = client_address
         self.raw_request = raw_request
+        self._form_data = None
 
         if raw_request is None:
             raise ValueError("raw_request cannot be None")
@@ -117,6 +254,53 @@ def body(self) -> bytes:
     def body(self, body: bytes) -> None:
         self.raw_request = self._raw_header_bytes + b"\r\n\r\n" + body
 
+    @property
+    def form_data(self) -> Union[FormData, None]:
+        """
+        POST data of the request.
+
+        Example::
+
+            # application/x-www-form-urlencoded
+            request = Request(...,
+                raw_request=b\"\"\"...
+                foo=bar&baz=qux\"\"\"
+            )
+
+            # or
+
+            # multipart/form-data
+            request = Request(...,
+                raw_request=b\"\"\"...
+                --boundary
+                Content-Disposition: form-data; name="foo"
+
+                bar
+                --boundary
+                Content-Disposition: form-data; name="baz"
+
+                qux
+                --boundary--\"\"\"
+            )
+
+            # or
+
+            # text/plain
+            request = Request(...,
+                raw_request=b\"\"\"...
+                foo=bar
+                baz=qux
+                \"\"\"
+            )
+
+            request.form_data                  # FormData({'foo': ['bar'], 'baz': ['qux']})
+            request.form_data["foo"]           # "bar"
+            request.form_data.get_list("baz")  # ["qux"]
+        """
+        if self._form_data is None and self.method == "POST":
+            self._form_data = FormData(self.body, self.headers["Content-Type"])
+        return self._form_data
+
     def json(self) -> Union[dict, None]:
         """Body of the request, as a JSON-decoded dictionary."""
         return json.loads(self.body) if self.body else None
@@ -148,13 +332,7 @@ def _parse_start_line(header_bytes: bytes) -> Tuple[str, str, Dict[str, str], st
 
         path, query_string = path.split("?", 1)
 
-        query_params = {}
-        for query_param in query_string.split("&"):
-            if "=" in query_param:
-                key, value = query_param.split("=", 1)
-                query_params[key] = value
-            elif query_param:
-                query_params[query_param] = ""
+        query_params = QueryParams(query_string)
 
         return method, path, query_params, http_version
 

adafruit_httpserver/response.py

@@ -305,7 +305,8 @@ def _send(self) -> None:
         self._send_headers()
 
         for chunk in self._body():
-            self._send_chunk(chunk)
+            if 0 < len(chunk):  # Don't send empty chunks
+                self._send_chunk(chunk)
 
         # Empty chunk to indicate end of response
         self._send_chunk()