commit a46242999bf494949d7d8afe8472c45648cc0389
Author: Kayomn <kayomn@kayomn.net>
Date:   Thu Sep 30 00:21:18 2021 +0100

    Initial commit

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..c0a4daa
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,8 @@
+# Editors
+.idea/
+
+# Caches
+__pycache__/
+
+# Virtual environments
+venv/
diff --git a/client.py b/client.py
new file mode 100644
index 0000000..83cd2f6
--- /dev/null
+++ b/client.py
@@ -0,0 +1,26 @@
+__author__ = "Kieran Osborne"
+__version__ = "0.0.1"
+__status__ = "Development"
+
+if (__name__ == "__main__"):
+    import config
+    import socket as network
+    import message
+
+    def init() -> None:
+        address = (config.host, config.port)
+
+        print("Starting connection to", address)
+
+        with network.socket(network.AF_INET, network.SOCK_STREAM) as socket:
+            socket.setblocking(False)
+            socket.connect_ex(address)
+
+            while True:
+                message_body = input("Enter a message: ")
+
+                print("\n")
+                socket.send(message.serialize("Kayomn", message_body))
+
+    init()
+
diff --git a/config.py b/config.py
new file mode 100644
index 0000000..5c8e395
--- /dev/null
+++ b/config.py
@@ -0,0 +1,6 @@
+__author__ = "Kieran Osborne"
+__version__ = "0.0.1"
+__status__ = "Development"
+
+host = "127.0.0.1"
+port = 12345
diff --git a/message.py b/message.py
new file mode 100644
index 0000000..e50942a
--- /dev/null
+++ b/message.py
@@ -0,0 +1,32 @@
+import sys
+import json
+import struct
+
+
+class Message:
+    def __init__(self, author: str, body: str) -> None:
+        self.author = author
+        self.body = body
+
+    def serialize(self) -> bytes:
+        return serialize(self.author, self.body)
+
+
+def deserialize(data: bytes) -> Message:
+    buffer_length = 2
+    header_length = struct.unpack(">H", data[:buffer_length])[0]
+    header = json.loads(data[buffer_length:header_length])
+
+    return Message(header["author"], header["encoded-body"])
+
+
+def serialize(author: str, body: str) -> bytes:
+    encoding = sys.getdefaultencoding()
+
+    header_bytes = json.dumps({
+        "byteorder": sys.byteorder,
+        "author": author,
+        "body": encoding,
+    }).encode("utf-8")
+
+    return (struct.pack(">H", len(header_bytes)) + header_bytes)
\ No newline at end of file
diff --git a/server.py b/server.py
new file mode 100644
index 0000000..1c64d69
--- /dev/null
+++ b/server.py
@@ -0,0 +1,104 @@
+__author__ = "Kieran Osborne"
+__version__ = "0.0.1"
+__status__ = "Development"
+
+if (__name__ == "__main__"):
+    import config
+    import traceback
+    import socket as network
+    import selectors
+    import message
+
+    class User:
+        def __init__(self, user_socket: network.socket):
+            self.socket = user_socket
+            self.connection, self.address = user_socket.accept()
+            self.selector = selectors.DefaultSelector()
+
+            print("Accepted connection from", self.address)
+            self.connection.setblocking(False)
+
+        def close(self):
+            self.selector.close()
+            self.socket.close()
+
+        def read(self):
+            try:
+                # Should be ready to read
+                data = self.socket.recv(4096)
+            except BlockingIOError:
+                # Resource temporarily unavailable (errno EWOULDBLOCK)
+                pass
+            else:
+                if data:
+                    print(message.deserialize(data))
+                else:
+                    raise RuntimeError("Peer closed.")
+
+        def write(self):
+            pass
+
+        def run(self):
+            try:
+                while True:
+                    events = self.selector.select(timeout=None)
+
+                    for (key, mask) in events:
+                        try:
+                            if (mask & selectors.EVENT_READ):
+                                self.read()
+
+                            elif (mask & selectors.EVENT_WRITE):
+                                self.write()
+
+                        except Exception:
+                            print(f"Exception raised on {self.address}: {traceback.format_exc()}"),
+                            self.socket.close()
+
+                    if not self.selector.get_map():
+                        break
+
+            except KeyboardInterrupt:
+                print("caught keyboard interrupt, exiting")
+
+            finally:
+                self.selector.close()
+
+    def init():
+        address = (config.host, config.port)
+        selector = selectors.DefaultSelector()
+
+        with network.socket(network.AF_INET, network.SOCK_STREAM) as socket:
+            # Avoid bind() exception: OSError: [Errno 48] Address already in use
+            socket.setsockopt(network.SOL_SOCKET, network.SO_REUSEADDR, 1)
+            socket.bind(address)
+            socket.listen()
+
+            print("Listening on", address)
+
+            socket.setblocking(False)
+            selector.register(socket, selectors.EVENT_READ, data=None)
+
+            users = []
+
+            try:
+                while True:
+                    events = selector.select(timeout=None)
+
+                    for (key, mask) in events:
+                        if key.data is None:
+                            user = User(key.fileobj)
+
+                            users.append(user)
+                            user.run()
+
+            except KeyboardInterrupt:
+                print("Caught keyboard interrupt, exiting")
+
+            finally:
+                for user in users:
+                    user.close()
+
+                selector.close()
+
+    init()