Made almost the entire networking guts replaceable.

CHANGELOG.md

@@ -10,6 +10,7 @@
 - New `utils.format_grid` for easily displaying long lists of items in a block.
 - Using `lunr` search indexing for better `help` matching and suggestions. Also improve
   the main help command's default listing output.
+- Made most of the networking classes such as Protocols and the SessionHandlers replaceable via `settings.py` for modding enthusiasts.
 
 
 ### Already in master

evennia/server/portal/amp.py

@@ -15,7 +15,7 @@ import zlib  # Used in Compressed class
 import pickle
 
 from twisted.internet.defer import DeferredList, Deferred
-from evennia.utils.utils import to_str, variable_from_module
+from evennia.utils.utils import variable_from_module
 
 # delayed import
 _LOGGER = None

evennia/server/portal/portal.py

@@ -25,7 +25,7 @@ import evennia
 
 evennia._init()
 
-from evennia.utils.utils import get_evennia_version, mod_import, make_iter
+from evennia.utils.utils import get_evennia_version, mod_import, make_iter, class_from_module
 from evennia.server.portal.portalsessionhandler import PORTAL_SESSIONS
 from evennia.utils import logger
 from evennia.server.webserver import EvenniaReverseProxyResource
@@ -261,6 +261,7 @@ if TELNET_ENABLED:
     # Start telnet game connections
 
     from evennia.server.portal import telnet
+    _telnet_protocol = class_from_module(settings.TELNET_PROTOCOL_CLASS)
 
     for interface in TELNET_INTERFACES:
         ifacestr = ""
@@ -270,7 +271,7 @@ if TELNET_ENABLED:
             pstring = "%s:%s" % (ifacestr, port)
             factory = telnet.TelnetServerFactory()
             factory.noisy = False
-            factory.protocol = telnet.TelnetProtocol
+            factory.protocol = _telnet_protocol
             factory.sessionhandler = PORTAL_SESSIONS
             telnet_service = internet.TCPServer(port, factory, interface=interface)
             telnet_service.setName("EvenniaTelnet%s" % pstring)
@@ -284,6 +285,7 @@ if SSL_ENABLED:
     # Start Telnet+SSL game connection (requires PyOpenSSL).
 
     from evennia.server.portal import telnet_ssl
+    _ssl_protocol = class_from_module(settings.SSL_PROTOCOL_CLASS)
 
     for interface in SSL_INTERFACES:
         ifacestr = ""
@@ -294,7 +296,7 @@ if SSL_ENABLED:
             factory = protocol.ServerFactory()
             factory.noisy = False
             factory.sessionhandler = PORTAL_SESSIONS
-            factory.protocol = telnet_ssl.SSLProtocol
+            factory.protocol = _ssl_protocol
 
             ssl_context = telnet_ssl.getSSLContext()
             if ssl_context:
@@ -317,6 +319,7 @@ if SSH_ENABLED:
     # evennia/game if necessary.
 
     from evennia.server.portal import ssh
+    _ssh_protocol = class_from_module(settings.SSH_PROTOCOL_CLASS)
 
     for interface in SSH_INTERFACES:
         ifacestr = ""
@@ -326,7 +329,7 @@ if SSH_ENABLED:
             pstring = "%s:%s" % (ifacestr, port)
             factory = ssh.makeFactory(
                 {
-                    "protocolFactory": ssh.SshProtocol,
+                    "protocolFactory": _ssh_protocol,
                     "protocolArgs": (),
                     "sessions": PORTAL_SESSIONS,
                 }
@@ -345,6 +348,7 @@ if WEBSERVER_ENABLED:
     # Start a reverse proxy to relay data to the Server-side webserver
 
     websocket_started = False
+    _websocket_protocol = class_from_module(settings.WEBSOCKET_PROTOCOL_CLASS)
     for interface in WEBSERVER_INTERFACES:
         ifacestr = ""
         if interface not in ("0.0.0.0", "::") or len(WEBSERVER_INTERFACES) > 1:
@@ -379,7 +383,7 @@ if WEBSERVER_ENABLED:
 
                     factory = Websocket()
                     factory.noisy = False
-                    factory.protocol = webclient.WebSocketClient
+                    factory.protocol = _websocket_protocol
                     factory.sessionhandler = PORTAL_SESSIONS
                     websocket_service = internet.TCPServer(port, factory, interface=w_interface)
                     websocket_service.setName("EvenniaWebSocket%s:%s" % (w_ifacestr, port))

evennia/server/portal/portalsessionhandler.py

@@ -9,6 +9,7 @@ from twisted.internet import reactor
 from django.conf import settings
 from evennia.server.sessionhandler import SessionHandler, PCONN, PDISCONN, PCONNSYNC, PDISCONNALL
 from evennia.utils.logger import log_trace
+from evennia.utils.utils import class_from_module
 
 # module import
 _MOD_IMPORT = None
@@ -32,9 +33,10 @@ DUMMYSESSION = namedtuple("DummySession", ["sessid"])(0)
 # -------------------------------------------------------------
 # Portal-SessionHandler class
 # -------------------------------------------------------------
+_BASE_HANDLER_CLASS = class_from_module(settings.SERVER_SESSION_HANDLER_CLASS)
 
 
-class PortalSessionHandler(SessionHandler):
+class PortalSessionHandler(_BASE_HANDLER_CLASS):
     """
     This object holds the sessions connected to the portal at any time.
     It is synced with the server's equivalent SessionHandler over the AMP
@@ -463,4 +465,6 @@ class PortalSessionHandler(SessionHandler):
                         log_trace()
 
 
-PORTAL_SESSIONS = PortalSessionHandler()
+_portal_sessionhandler_class = class_from_module(settings.PORTAL_SESSION_HANDLER_CLASS)
+
+PORTAL_SESSIONS = _portal_sessionhandler_class()

evennia/server/portal/ssh.py

@@ -43,10 +43,9 @@ from twisted.conch import interfaces as iconch
 from twisted.python import components
 from django.conf import settings
 
-from evennia.server import session
 from evennia.accounts.models import AccountDB
 from evennia.utils import ansi
-from evennia.utils.utils import to_str
+from evennia.utils.utils import to_str, class_from_module
 
 _RE_N = re.compile(r"\|n$")
 _RE_SCREENREADER_REGEX = re.compile(
@@ -74,6 +73,8 @@ and put them here:
     _PRIVATE_KEY_FILE, _PUBLIC_KEY_FILE
 )
 
+_BASE_SESSION = class_from_module(settings.BASE_SESSION_CLASS)
+
 
 # not used atm
 class SSHServerFactory(protocol.ServerFactory):
@@ -84,7 +85,7 @@ class SSHServerFactory(protocol.ServerFactory):
         return "SSH"
 
 
-class SshProtocol(Manhole, session.Session):
+class SshProtocol(Manhole, _BASE_SESSION):
     """
     Each account connecting over ssh gets this protocol assigned to
     them.  All communication between game and account goes through

evennia/server/portal/ssl.py

@@ -18,7 +18,7 @@ except ImportError as error:
     raise ImportError(errstr.format(err=error))
 
 from django.conf import settings
-from evennia.server.portal.telnet import TelnetProtocol
+from evennia.utils.utils import class_from_module
 
 _GAME_DIR = settings.GAME_DIR
 
@@ -43,8 +43,10 @@ example (linux, using the openssl program):
     {exestring}
 """
 
+_TELNET_PROTOCOL = class_from_module(settings.TELNET_PROTOCOL_CLASS)
 
-class SSLProtocol(TelnetProtocol):
+
+class SSLProtocol(_TELNET_PROTOCOL):
     """
     Communication is the same as telnet, except data transfer
     is done with encryption.

evennia/server/portal/telnet.py

@@ -25,12 +25,11 @@ from twisted.conch.telnet import (
     LINEMODE_TRAPSIG,
 )
 from django.conf import settings
-from evennia.server.session import Session
 from evennia.server.portal import ttype, mssp, telnet_oob, naws, suppress_ga
 from evennia.server.portal.mccp import Mccp, mccp_compress, MCCP
 from evennia.server.portal.mxp import Mxp, mxp_parse
 from evennia.utils import ansi
-from evennia.utils.utils import to_bytes
+from evennia.utils.utils import to_bytes, class_from_module
 
 _RE_N = re.compile(r"\|n$")
 _RE_LEND = re.compile(br"\n$|\r$|\r\n$|\r\x00$|", re.MULTILINE)
@@ -56,6 +55,10 @@ _HTTP_WARNING = bytes(
 )
 
 
+_BASE_SESSION = class_from_module(settings.BASE_SESSION_CLASS)
+
+
+
 class TelnetServerFactory(protocol.ServerFactory):
     "This is only to name this better in logs"
     noisy = False
@@ -64,7 +67,7 @@ class TelnetServerFactory(protocol.ServerFactory):
         return "Telnet"
 
 
-class TelnetProtocol(Telnet, StatefulTelnetProtocol, Session):
+class TelnetProtocol(Telnet, StatefulTelnetProtocol, _BASE_SESSION):
     """
     Each player connecting over telnet (ie using most traditional mud
     clients) gets a telnet protocol instance assigned to them.  All

evennia/server/portal/webclient.py

@@ -17,10 +17,8 @@ from the command line and interprets it as an Evennia Command: `["text", ["look"
 import re
 import json
 import html
-from twisted.internet.protocol import Protocol
 from django.conf import settings
-from evennia.server.session import Session
-from evennia.utils.utils import to_str, mod_import
+from evennia.utils.utils import mod_import, class_from_module
 from evennia.utils.ansi import parse_ansi
 from evennia.utils.text2html import parse_html
 from autobahn.twisted.websocket import WebSocketServerProtocol
@@ -39,8 +37,10 @@ CLOSE_NORMAL = WebSocketServerProtocol.CLOSE_STATUS_CODE_NORMAL
 #   called when the browser is navigating away from the page
 GOING_AWAY = WebSocketServerProtocol.CLOSE_STATUS_CODE_GOING_AWAY
 
+_BASE_SESSION = class_from_module(settings.BASE_SESSION_CLASS)
 
-class WebSocketClient(WebSocketServerProtocol, Session):
+
+class WebSocketClient(WebSocketServerProtocol, _BASE_SESSION):
     """
     Implements the server-side of the Websocket connection.
     """

evennia/server/session.py

@@ -36,24 +36,7 @@ class Session(object):
     """
 
     # names of attributes that should be affected by syncing.
-    _attrs_to_sync = (
-        "protocol_key",
-        "address",
-        "suid",
-        "sessid",
-        "uid",
-        "csessid",
-        "uname",
-        "logged_in",
-        "puid",
-        "conn_time",
-        "cmd_last",
-        "cmd_last_visible",
-        "cmd_total",
-        "protocol_flags",
-        "server_data",
-        "cmdset_storage_string",
-    )
+    _attrs_to_sync = settings.SESSION_SYNC_ATTRS
 
     def init_session(self, protocol_key, address, sessionhandler):
         """

evennia/server/sessionhandler.py

@@ -23,6 +23,7 @@ from evennia.utils.utils import (
     make_iter,
     delay,
     callables_from_module,
+    class_from_module
 )
 from evennia.server.signals import SIGNAL_ACCOUNT_POST_LOGIN, SIGNAL_ACCOUNT_POST_LOGOUT
 from evennia.server.signals import SIGNAL_ACCOUNT_POST_FIRST_LOGIN, SIGNAL_ACCOUNT_POST_LAST_LOGOUT
@@ -857,5 +858,9 @@ class ServerSessionHandler(SessionHandler):
                     log_trace()
 
 
-SESSION_HANDLER = ServerSessionHandler()
+# import class from settings
+_session_handler_class = class_from_module(settings.SERVER_SESSION_HANDLER_CLASS)
+
+# Instantiate class. These globals are used to provide singleton-like behavior.
+SESSION_HANDLER = _session_handler_class()
 SESSIONS = SESSION_HANDLER  # legacy

evennia/settings_default.py

@@ -465,9 +465,6 @@ CHANNEL_COMMAND_CLASS = "evennia.comms.channelhandler.ChannelCommand"
 # Typeclasses and other paths
 ######################################################################
 
-# Server-side session class used.
-SERVER_SESSION_CLASS = "evennia.server.serversession.ServerSession"
-
 # These are paths that will be prefixed to the paths given if the
 # immediately entered path fail to find a typeclass. It allows for
 # shorter input strings. They must either base off the game directory
@@ -511,6 +508,70 @@ START_LOCATION = "#2"
 # issues.
 TYPECLASS_AGGRESSIVE_CACHE = True
 
+######################################################################
+# Networking Replaceable Guts
+######################################################################
+# Modify the things below at your own risk. This is here be dragons territory.
+
+# The Base Session Class is used as a parent class for all Protocols such as
+# Telnet and SSH.) Changing this could be really dangerous. It will cascade
+# to tons of classes. You generally shouldn't need to touch protocols.
+BASE_SESSION_CLASS = "evennia.server.session.Session"
+
+# Telnet Protocol inherits from whatever above BASE_SESSION_CLASS is specified.
+# It is used for all telnet connections, and is also inherited by the SSL Protocol
+# (which is just TLS + Telnet).
+TELNET_PROTOCOL_CLASS = "evennia.server.portal.telnet.TelnetProtocol"
+SSL_PROTOCOL_CLASS = "evennia.server.portal.ssl.SSLProtocol"
+
+# Websocket Client Protocol. This inherits from BASE_SESSION_CLASS. It is used
+# for all webclient connections.
+WEBSOCKET_PROTOCOL_CLASS = "evennia.server.portal.webclient.WebSocketClient"
+
+# Protocol for the SSH interface. This inherits from BASE_SESSION_CLASS.
+SSH_PROTOCOL_CLASS = "evennia.server.portal.ssh.SshProtocol"
+
+# Server-side session class used. This will inherit from BASE_SESSION_CLASS.
+# This one isn't as dangerous to replace.
+SERVER_SESSION_CLASS = "evennia.server.serversession.ServerSession"
+
+# The Server SessionHandler manages all ServerSessions, handling logins,
+# ensuring the login process happens smoothly, handling expected and
+# unexpected disconnects. You shouldn't need to touch it, but you can.
+# Replace it to implement altered game logic.
+SERVER_SESSION_HANDLER_CLASS = "evennia.server.sessionhandler.ServerSessionHandler"
+
+# The Portal SessionHandler manages all incoming connections regardless of
+# the protocol in use. It is responsible for keeping them going and informing
+# the Server Session Handler of the connections and synchronizing them across the
+# AMP connection. You shouldn't ever need to change this. But you can.
+PORTAL_SESSION_HANDLER_CLASS = "evennia.server.portal.portalsessionhandler.PortalSessionHandler"
+
+
+# These are members / properties / attributes kept on both Server and
+# Portal Sessions. They are sync'd at various points, such as logins and
+# reloads. If you add to this, you may need to adjust the class __init__
+# so the additions have somewhere to go. These must be simple things that
+# can be pickled - stuff you could serialize to JSON is best.
+SESSION_SYNC_ATTRS = (
+        "protocol_key",
+        "address",
+        "suid",
+        "sessid",
+        "uid",
+        "csessid",
+        "uname",
+        "logged_in",
+        "puid",
+        "conn_time",
+        "cmd_last",
+        "cmd_last_visible",
+        "cmd_total",
+        "protocol_flags",
+        "server_data",
+        "cmdset_storage_string"
+    )
+
 ######################################################################
 # Options and validators
 ######################################################################