Parse html with regex, fix small issues

client/command.py

@@ -3,39 +3,40 @@ from abc import ABC, abstractmethod
 from typing import Dict, Tuple
 from urllib.parse import urlparse
 
-from client.httpclient import FORMAT, HTTPClient
+from client.httpclient import HTTPClient
 from httplib import parser
 from httplib.exceptions import InvalidResponse, InvalidStatusLine, UnsupportedEncoding
+from httplib.httpsocket import FORMAT
 from httplib.message import ClientMessage as Message
 from httplib.retriever import PreambleRetriever
 
 sockets: Dict[str, HTTPClient] = {}
 
 
-def create(command: str, url: str, port):
+def create(method: str, url: str, port):
     """
-    Create a corresponding Command instance of the specified HTTP `command` with the specified `url` and `port`.
+    Create a corresponding Command instance of the specified HTTP `method` with the specified `url` and `port`.
-    @param command: The command type to create
+    @param method: The command type to create
     @param url: The url for the command
     @param port: The port for the command
     """
 
     uri = parser.get_uri(url)
-    if command == "GET":
+    if method == "GET":
         return GetCommand(uri, port)
-    elif command == "HEAD":
+    elif method == "HEAD":
         return HeadCommand(uri, port)
-    elif command == "POST":
+    elif method == "POST":
         return PostCommand(uri, port)
-    elif command == "PUT":
+    elif method == "PUT":
         return PutCommand(uri, port)
     else:
-        raise ValueError()
+        raise ValueError("Unknown HTTP method")
 
 
 class AbstractCommand(ABC):
     """
-    A class representing the command for sending an HTTP command.
+    A class representing the command for sending an HTTP request.
     """
     uri: str
     host: str
@@ -51,10 +52,15 @@ class AbstractCommand(ABC):
 
     @property
     @abstractmethod
-    def command(self):
+    def method(self):
         pass
 
     def execute(self, sub_request=False):
+        """
+        Creates and sends the HTTP message for this Command.
+
+        @param sub_request: If this execution is in function of a prior command.
+        """
         self.sub_request = sub_request
         (host, path) = self.parse_uri()
 
@@ -69,9 +75,10 @@ class AbstractCommand(ABC):
             client.conn.connect((host, self.port))
             sockets[host] = client
 
-        message = f"{self.command} {path} HTTP/1.1\r\n"
+        message = f"{self.method} {path} HTTP/1.1\r\n"
         message += f"Host: {host}:{self.port}\r\n"
-        message += "Accept: */*\r\nAccept-Encoding: identity\r\n"
+        message += "Accept: */*\r\n"
+        message += "Accept-Encoding: identity\r\n"
         encoded_msg = self._build_message(message)
 
         logging.debug("---request begin---\r\n%s---request end---", encoded_msg.decode(FORMAT))
@@ -81,8 +88,7 @@ class AbstractCommand(ABC):
         logging.info("HTTP request sent, awaiting response...")
 
         try:
-            retriever = PreambleRetriever(client)
+            self._await_response(client)
-            self._await_response(client, retriever)
         except InvalidResponse as e:
             logging.debug("Internal error: Response could not be parsed", exc_info=e)
             return
@@ -95,7 +101,12 @@ class AbstractCommand(ABC):
             if not sub_request:
                 client.close()
 
-    def _await_response(self, client, retriever):
+    def _await_response(self, client):
+        """
+        Simple response method.
+
+        Receives the response and prints to stdout.
+        """
         while True:
             line = client.read_line()
             print(line, end="")
@@ -106,11 +117,15 @@ class AbstractCommand(ABC):
         return (message + "\r\n").encode(FORMAT)
 
     def parse_uri(self):
+        """
+        Parses the URI and returns the hostname and path.
+        @return: A tuple of the hostname and path.
+        """
         parsed = urlparse(self.uri)
 
         # If there is no netloc, the url is invalid, so prepend `//` and try again
         if parsed.netloc == "":
-            parsed = urlparse("//" + self.uri)
+            parsed = urlparse("http://" + self.uri)
 
         host = parsed.netloc
         path = parsed.path
@@ -126,11 +141,11 @@ class AbstractCommand(ABC):
 
 class AbstractWithBodyCommand(AbstractCommand, ABC):
     """
-    The building block for creating an HTTP message for an HTTP command with a body.
+    The building block for creating an HTTP message for an HTTP method with a body (POST and PUT).
     """
 
     def _build_message(self, message: str) -> bytes:
-        body = input(f"Enter {self.command} data: ").encode(FORMAT)
+        body = input(f"Enter {self.method} data: ").encode(FORMAT)
         print()
 
         message += "Content-Type: text/plain\r\n"
@@ -145,29 +160,36 @@ class AbstractWithBodyCommand(AbstractCommand, ABC):
 
 class HeadCommand(AbstractCommand):
     """
-    A Command for sending a `HEAD` message.
+    A Command for sending a `HEAD` request.
     """
 
     @property
-    def command(self):
+    def method(self):
         return "HEAD"
 
 
 class GetCommand(AbstractCommand):
     """
-    A Command for sending a `GET` message.
+    A Command for sending a `GET` request.
     """
+    dir: str
 
-    def __init__(self, uri: str, port, dir=None):
+    def __init__(self, uri: str, port, directory=None):
         super().__init__(uri, port)
-        self.dir = dir
+        self.dir = directory
         self.filename = None
 
     @property
-    def command(self):
+    def method(self):
         return "GET"
 
-    def _get_preamble(self, retriever):
+    def _get_preamble(self, client):
+        """
+        Returns the preamble (start-line and headers) of the response of this command.
+        @param client: the client object to retrieve from
+        @return: A Message object containing the HTTP-version, status code, status message, headers and buffer
+        """
+        retriever = PreambleRetriever(client)
         lines = retriever.retrieve()
         (version, status, msg) = parser.parse_status_line(next(lines))
         headers = parser.parse_headers(lines)
@@ -177,8 +199,11 @@ class GetCommand(AbstractCommand):
 
         return Message(version, status, msg, headers, buffer)
 
-    def _await_response(self, client, retriever):
+    def _await_response(self, client):
-        msg = self._get_preamble(retriever)
+        """
+        Handles the response of this command.
+        """
+        msg = self._get_preamble(client)
 
         from client import response_handler
         self.filename = response_handler.handle(client, msg, self, self.dir)
@@ -186,19 +211,19 @@ class GetCommand(AbstractCommand):
 
 class PostCommand(AbstractWithBodyCommand):
     """
-    A command for sending a `POST` command.
+    A command for sending a `POST` request.
     """
 
     @property
-    def command(self):
+    def method(self):
         return "POST"
 
 
 class PutCommand(AbstractWithBodyCommand):
     """
-    A command for sending a `PUT` command.
+    A command for sending a `PUT` request.
     """
 
     @property
-    def command(self):
+    def method(self):
         return "PUT"

client/httpclient.py

@@ -2,11 +2,6 @@ import socket
 
 from httplib.httpsocket import HTTPSocket, InvalidResponse
 
-BUFSIZE = 4096
-TIMEOUT = 3
-FORMAT = "UTF-8"
-MAXLINE = 4096
-
 
 class HTTPClient(HTTPSocket):
     host: str

client/response_handler.py

@@ -4,15 +4,17 @@ import re
 from abc import ABC, abstractmethod
 from urllib.parse import urlsplit, unquote
 
-from bs4 import BeautifulSoup, Tag
-
 from client.command import AbstractCommand, GetCommand
-from client.httpclient import HTTPClient, FORMAT
+from client.httpclient import HTTPClient
 from httplib import parser
 from httplib.exceptions import InvalidResponse
+from httplib.httpsocket import FORMAT
 from httplib.message import ClientMessage as Message
 from httplib.retriever import Retriever
 
+BASE_REGEX = re.compile(r"<\s*base.*href\s*=\s*['\"](\S*)['\"][^>]*>", re.M | re.I)
+IMG_REGEX = re.compile(r"<\s*img[^>]*\ssrc\s*=\s*['\"]([^\"']+)['\"][^>]*>", re.M | re.I)
+
 
 def handle(client: HTTPClient, msg: Message, command: AbstractCommand, directory=None):
     handler = BasicResponseHandler(client, msg, command)
@@ -83,8 +85,10 @@ class BasicResponseHandler(ResponseHandler):
 
         if 300 <= self.msg.status < 400:
             # Redirect
+            self._skip_body()
             return self._do_handle_redirect()
         if 400 <= self.msg.status < 600:
+            self._skip_body()
             # Dump headers and exit with error
             if not self.cmd.sub_request:
                 print("".join(self.msg.raw), end="")
@@ -93,8 +97,6 @@ class BasicResponseHandler(ResponseHandler):
         return None
 
     def _do_handle_redirect(self):
-        self._skip_body()
-
         if self.msg.status == 304:
             print("".join(self.msg.raw), end="")
             return None
@@ -203,40 +205,61 @@ class HTMLDownloadHandler(DownloadHandler):
             file.write(buffer)
         file.close()
 
-        self._download_images(tmp_path, self.path)
+        charset = parser.get_charset(self.msg.headers)
+        self._download_images(tmp_path, self.path, charset)
         os.remove(tmp_path)
         return self.path
 
-    def _download_images(self, tmp_filename, target_filename):
+    def _download_images(self, tmp_filename, target_filename, charset=FORMAT):
 
-        with open(tmp_filename, "rb") as fp:
+        try:
-            soup = BeautifulSoup(fp, 'lxml')
+            fp = open(tmp_filename, "r", encoding=charset)
+            html = fp.read()
+        except UnicodeDecodeError:
+            fp = open(tmp_filename, "r", encoding=FORMAT, errors="replace")
+            html = fp.read()
 
-            base_element = soup.find("base")
+        fp.close()
 
+        base_element = BASE_REGEX.search(html)
         base_url = self.cmd.uri
         if base_element:
-                base_url = parser.urljoin(self.cmd.uri, base_element["href"])
+            base_url = parser.urljoin(self.cmd.uri, base_element.group(1))
 
         processed = {}
-            tag: Tag
+        to_replace = []
-            for tag in soup.find_all("img"):
+
+        for m in IMG_REGEX.finditer(html):
+            url_start = m.start(1)
+            url_end = m.end(1)
+            target = m.group(1)
+
             try:
-                    if not tag.has_attr("src"):
+                if len(target) == 0:
+                    continue
+                if target in processed:
+                    new_url = processed.get(target)
+                else:
+                    new_url = self.__download_image(target, base_url)
+                    if not new_url:
+                        # Image failed to download
                         continue
 
-                    if tag["src"] in processed:
+                    processed[target] = new_url
-                        new_url = processed.get(tag["src"])
-                    else:
-                        new_url = self.__download_image(tag["src"], base_url)
-                        processed[tag["src"]] = new_url
-                    if new_url:
-                        tag["src"] = os.path.basename(new_url)
-                except Exception as e:
-                    logging.error("Failed to download image: %s, skipping...", tag["src"], exc_info=e)
 
-        with open(target_filename, 'w') as file:
+                if new_url:
-            file.write(soup.prettify(formatter="minimal"))
+                    local_path = os.path.basename(new_url)
+                    to_replace.append((url_start, url_end, local_path))
+
+            except Exception as e:
+                logging.error("Failed to download image: %s, skipping...", target, exc_info=e)
+
+        to_replace.reverse()
+        for (start, end, path) in to_replace:
+            html = html[:start] + path + html[end:]
+
+        with open(target_filename, 'w', encoding=FORMAT) as file:
+            file.write(html)
 
     def __download_image(self, img_src, base_url):
         """

httplib/parser.py

@@ -1,9 +1,11 @@
 import logging
 import re
 import urllib
+from typing import Dict
 from urllib.parse import urlparse, urlsplit
 
 from httplib.exceptions import InvalidStatusLine, InvalidResponse, BadRequest, InvalidRequestLine
+from httplib.httpsocket import FORMAT
 
 
 def _is_valid_http_version(http_version: str):
@@ -164,7 +166,7 @@ def get_uri(url: str):
     parsed = urlsplit(url)
 
     result = f"http://{parsed.netloc}{parsed.path}"
-    if parsed.query != '':
+    if parsed.query != "":
         result = f"{result}?{parsed.query}"
 
     return result
@@ -175,3 +177,13 @@ def urljoin(base, url):
     Join a base url and a URL to form a absolute url.
     """
     return urllib.parse.urljoin(base, url)
+
+
+def get_charset(headers: Dict[str, str]):
+    if "content-type" in headers:
+        content_type = headers["content-type"]
+        match = re.search(r"charset\s*=\s*([a-z\-0-9]*)", content_type, re.I)
+        if match:
+            return match.group(1)
+
+    return FORMAT

requirements.txt

@@ -1,3 +1 @@
-beautifulsoup4~=4.9.3
 lxml~=4.6.2
-cssutils~=2.2.0

server/command.py

@@ -6,12 +6,12 @@ from datetime import datetime
 from time import mktime
 from wsgiref.handlers import format_date_time
 
-from client.httpclient import FORMAT
 from httplib import parser
 from httplib.exceptions import NotFound, Forbidden, NotModified
+from httplib.httpsocket import FORMAT
 from httplib.message import ServerMessage as Message
 
-root = os.path.join(os.path.dirname(sys.argv[0]), "public")
+CONTENT_ROOT = os.path.join(os.path.dirname(sys.argv[0]), "public")
 
 status_message = {
     200: "OK",
@@ -26,6 +26,12 @@ status_message = {
 
 
 def create(message: Message):
+    """
+    Creates a Command based on the specified message
+    @param message: the message to create the Command with.
+    @return: An instance of `AbstractCommand`
+    """
+
     if message.method == "GET":
         return GetCommand(message)
     elif message.method == "HEAD":
@@ -102,9 +108,9 @@ class AbstractCommand(ABC):
         norm_path = os.path.normpath(self.msg.target.path)
 
         if norm_path == "/":
-            path = root + "/index.html"
+            path = CONTENT_ROOT + "/index.html"
         else:
-            path = root + norm_path
+            path = CONTENT_ROOT + norm_path
 
         if check and not os.path.exists(path):
             raise NotFound(path)
@@ -169,7 +175,7 @@ class AbstractModifyCommand(AbstractCommand, ABC):
         else:
             status = 201
 
-        location = parser.urljoin("/", os.path.relpath(path, root))
+        location = parser.urljoin("/", os.path.relpath(path, CONTENT_ROOT))
         return self._build_message(status, "text/plain", b"", {"Location": location})
 
 

server/serversocket.py

@@ -3,11 +3,6 @@ import socket
 from httplib.exceptions import BadRequest
 from httplib.httpsocket import HTTPSocket
 
-BUFSIZE = 4096
-TIMEOUT = 3
-FORMAT = "UTF-8"
-MAXLINE = 4096
-
 
 class ServerSocket(HTTPSocket):