fn from_bytes()

in core/sdk/src/users/login_user.rs [112:176]
61 lines of code
4 McCabe index (conditional complexity)

    fn from_bytes(bytes: Bytes) -> Result<LoginUser, IggyError> {
        if bytes.len() < 4 {
            return Err(IggyError::InvalidCommand);
        }

        let username_length = bytes[0];
        let username = from_utf8(&bytes[1..=(username_length as usize)])
            .map_err(|_| IggyError::InvalidUtf8)?
            .to_string();
        if username.len() != username_length as usize {
            return Err(IggyError::InvalidCommand);
        }

        let password_length = bytes[1 + username_length as usize];
        let password = from_utf8(
            &bytes[2 + username_length as usize
                ..2 + username_length as usize + password_length as usize],
        )
        .map_err(|_| IggyError::InvalidUtf8)?
        .to_string();
        if password.len() != password_length as usize {
            return Err(IggyError::InvalidCommand);
        }

        let position = 2 + username_length as usize + password_length as usize;
        let version_length = u32::from_le_bytes(
            bytes[position..position + 4]
                .try_into()
                .map_err(|_| IggyError::InvalidNumberEncoding)?,
        );
        let version = match version_length {
            0 => None,
            _ => {
                let version =
                    from_utf8(&bytes[position + 4..position + 4 + version_length as usize])
                        .map_err(|_| IggyError::InvalidUtf8)?
                        .to_string();
                Some(version)
            }
        };
        let position = position + 4 + version_length as usize;
        let context_length = u32::from_le_bytes(
            bytes[position..position + 4]
                .try_into()
                .map_err(|_| IggyError::InvalidNumberEncoding)?,
        );
        let context = match context_length {
            0 => None,
            _ => {
                let context =
                    from_utf8(&bytes[position + 4..position + 4 + context_length as usize])
                        .map_err(|_| IggyError::InvalidUtf8)?
                        .to_string();
                Some(context)
            }
        };

        let command = LoginUser {
            username,
            password,
            version,
            context,
        };
        Ok(command)
    }