modular-bot-framework-for-telegram/main.py

from telegram.ext import Updater, MessageHandler, Filters
import datetime
import codecs
import time
import json
import sys
import os
import threading

# global variables
STOP_REQUESTED = False

# some functions that increase readability of the code
def readfile(filename):
    try:
        return codecs.open(filename, encoding = "utf-8").read()
    except FileNotFoundError:
        return False
    except Exception as e:
        print( "[ERROR] Unexpected error occured in readfile() ({0})".format(e) )
        return False

# module object classes
class ModuleV1:
    def __init__(self, path, code, enabled, alias, predefine):
        self.version = 1
        self.enabled = enabled
        self.code = code
        self.alias = alias
        self.path = path
        self.predefine = predefine

        if self.predefine:
            self.set_predefine()

    # set environmental variables
    def set_env(self):
        self.RESPONCE = ""

    def set_predefine(self):
        try:
            exec(self.predefine)
        except Exception as e:
            print("[ERROR] module: module \"{}\" ({}) raised exception \"{}\" during predefine stage, disabling it...".format(self.path, self.alias, e))

    # running the module
    def process(self, msg):
        self.set_env()

        self.MESSAGE = msg
        try:
            exec(self.code)
            return self.RESPONCE
        except Exception as e:
            print("[ERROR] module: module \"{}\" ({}) raised exception \"{}\"".format(self.path, self.alias, e))
            return ""


# module control unit
class ModuleControlUnit:
    def __init__(self):
        self.modules = []
        self.reload_modules()

        print("[INFO] ModuleControlUnit: initialized successfully")

    def reload_modules(self):
        for folder in os.listdir("modules/"):
            try:
                meta_raw = readfile("modules/{}/meta.json".format(folder))
                if not meta_raw:
                    print("[WARN] module_loader: no meta.json found in module folder \"{}\"".format(folder))
                    continue

                meta = json.loads( meta_raw )
                if "version" in meta:
                    if meta["version"] == 1:
                        if "index_file" in meta:
                            index_file = meta["index_file"]
                        else:
                            index_file = "index.py"

                        code = readfile( "modules/{}/{}".format(folder, index_file) )
                        if not code: # False both when readfile() returns False and when the code string is empty
                            print("[WARN] reload_modules: module {} does not have any code, skipping...".format(folder))
                            continue
                        
                        if "start_on_boot" in meta:
                            enabled = meta["start_on_boot"]
                        else:
                            enabled = False

                        if "alias" in meta:
                            alias = meta["alias"]
                        else:
                            alias = None

                        if "predefine" in meta:
                            predefine = readfile("modules/{}/{}".format(folder, meta["predefine"]))
                        else:
                            predefine = False

                        self.modules.append( ModuleV1( "modules/{}/".format(folder), code, enabled, alias, predefine ) )

                        print("[INFO] reload_modules: successfully loaded {} as {} (start_on_boot: {})".format(folder, alias, enabled))
                    else:
                        print("[WARN] reload_modules: module {} requires unsupported version ({} > 1), skipping...".format(folder, meta["version"]))
            except Exception as e:
                print("[ERROR] module_loader: error while loading module \"{}\" ({})".format(folder, e))

    def reload_module(self, folder_name):
        try:
            meta_raw = readfile("modules/{}/meta.json".format(folder))
            if not meta_raw:
                print("[WARN] module_loader: no meta.json found in module folder \"{}\"".format(folder_name))
                return 1

            meta = json.loads( readfile("modules/{}/meta.json".format(folder_name)) )
            if "version" in meta:
                if meta["version"] == 1:
                    if "index_file" in meta:
                        index_file = meta["index_file"]
                    else:
                        index_file = "index.py"

                    code = readfile( "modules/{}/{}".format(folder_name, index_file) )
                    if not code: # False both when readfile() returns False and when the code string is empty
                        print("[WARN] reload_modules: module {} does not have any code, skipping...".format(folder_name))
                
                    if "start_on_boot" in meta:
                        enabled = meta["start_on_boot"]
                    else:
                        enabled = False

                    if "alias" in meta:
                        alias = meta["alias"]
                    else:
                        alias = None

                    self.modules.append( ModuleV1( code, enabled, alias ) )

                    print("[INFO] reload_modules: successfully loaded {} as {} (start_on_boot: {})".format(folder_name, alias, enabled))
                else:
                    print("[WARN] reload_modules: module {} requires unsupported version ({} > 1), skipping...".format(folder_name, meta["version"]))
        except Exception as e:
            print("[ERROR] module_loader: error while loading module \"{}\" ({})".format(folder_name, e))

# message queue object to go back to synchronous message processing
#class MessageQueue:
#    def __init__(self):
#        print("[INFO] Initializing the message queue...")
#        self.queue = []


# synchronous message processor
def queue_processor():
    while True:
        try:
            if len(message_queue) > 0:
                msg = message_queue[0]
                print("[DEBUG] queue_processor: {}".format(msg)) # debug
    
                # check for control commands
                if msg["chat"]["id"] == 575246355:
                    if msg["text"][0] == "$":
                        command = msg["text"][1:].split(" ")
                        
                        if len(command) >= 2 and command[0] == "module":
                            if command[1] == "reload":
                                print("[INFO] Module reloading triggered by a command")
                                del mcu.modules[:]
                                mcu.reload_modules()
                        
                        del message_queue[0]
                        continue
    
                # modules are used in here
                for mod in mcu.modules:
                    if mod.enabled:
                        if mod.version == 1:
                            responce = mod.process(msg)
                            if len(responce) > 0:
                                updater.bot.send_message(chat_id = msg.chat.id, text = responce, disable_web_page_preview = True)
                                print("Responded using module {} ({}) with text: {}".format(mod.path, mod.alias, responce))
                                break
    
                del message_queue[0]

                time.sleep(0.1)
            else:
                if STOP_REQUESTED:
                    break
                else:
                    time.sleep(1)
        except Exception as e:
            print("[ERROR] queue_processor: current message queue: {}".format(message_queue))
            print("[ERROR] queue_processor: error while processing message, trying to delete it...")
            try:
                del message_queue[0]
                print("[INFO] queue_processor: deleted broken message from the queue")
            except:
                print("[WARN] queue_processor: message seems absent, whatever")

    print("[INFO] queue_processor thread stops successfully")


# telegram bot processor
def message_handler(update, context):
    print("[DEBUG] Received new message") # just for testing
    message_queue.append(update.message)


# --- Final stage ---


# initializing services and queues

message_queue = []

mcu = ModuleControlUnit()

processor_thread = threading.Thread( target = queue_processor, args = [] )
processor_thread.start()


# connecting to Telegram servers and listening for messages

TOKEN = readfile("config/token")
if not TOKEN:
    print("[CRIT] Token has not been defined, quitting")
    sys.exit(1)

# connect to Telegram servers
updater = Updater(TOKEN, use_context = True)
dispatcher = updater.dispatcher

# assign the handler for messages
dispatcher.add_handler(MessageHandler(Filters.text, message_handler))

# run the bot
updater.start_polling()
updater.idle()