Update README and MicromailClient to enhance documentation and ensure socket closure on quit

README.md

@@ -5,3 +5,48 @@
 Tiny SMTP client for Micropython. See [examples](examples) for usage.
 
 Inspired from [shawwwn/uMail](https://github.com/shawwwn/uMail).
+
+## Documentation
+
+### Class MicromailClient
+
+`class micromail.MicromailClient(host: str, port: int, ssl: bool=False, starttls: bool=False)`
+: Create a new SMTP client.
+
+`MicromailClient.connect()`
+: Establish a connection to the SMTP server. The connection is kept alive until `MicromailClient.quit()` is called.
+
+`MicromailClient.login(username: str, password: str)`
+: Login to the SMTP server with the provided username and password. `PLAIN` and `LOGIN` authentication methods are currently supported.
+
+`MicromailClient.write(data: bytearray)`
+: Write `data` of type `bytearray` on the server.
+
+`MicromailClient.send_command(*cmd: bytearray) -> code: bytearray, response: list[bytearray]`
+: Send command to the SMTP server; returns status code and response.
+
+`MicromailClient.ehlo() -> res: list[bytearray]`
+: Send SMTP EHLO command to the server and return response.
+
+`MicromailClient.starttls()`
+: Send SMTP STARTTLS command and enable SSL on socket.
+
+`MicromailClient.new_message(to: str|list[str], sender: None|str=None)`
+: Create a new email; sender defaults to username.
+
+`MicromailClient.headers(headers:dict={})`
+: Define email headers; supported headers are `date` (`str|datetime`, defaults to `datetime.now()`), `from` (`str`, defaults to `new_message` `sender`), `to` (`str|list[str]`, defaults to `new_message` `to`), `subject` (`str`).
+
+`MicromailClient.write_line(content:str|bytearray)`
+: Write message line; `\r\n` is appended to `content`.
+
+`MicromailClient.send()`
+: Send current email.
+
+`MicromailClient.quit()`
+: Quit the SMTP server and disconnect from socket.
+
+### Functions
+
+`format_date(date: datetime)`
+: Return date formatted as email date string.

micromail/__init__.py

@@ -198,6 +198,7 @@ class MicromailClient:
         if code != b"221":
             print(f"Error: got code {code} on QUIT")
         print("Disconnected from server")
+        self.socket.close()
 
 
 MONTHS = [