Creating Microsoft Bot Framework In Python 😍

Note

Python language support starts from Bot Framework SDK V4 and is in the preview stage.
Currently, the predefined template is not available for Visual Studio 2019. We are using Flask template to create the Bot Application.

This article focuses on how to write the “Hello World” application in Bot Framework using Python language. It has been divided into two sections. The first section focuses on the Project template changes and the next section focuses on the code changes.

Project template changes
Code file changes

First, I will start Project template changes,

Project template changes

Prerequisites

Visual Studio 2019 Preview (Version 16.4.0) and make sure Python development is installed.

Let’s Start Microsoft Bot Framework Via Python 😍 Step By Step Guide

Create a Project

The project type: “Blank Flask Web Project”.

Project Name

Enter the project name “HelloWorld” and create a project.

The project is successfully created.

Create a virtual environment

Go to the Solution Explorer and open the “requirements.txt” file and add the below namespace:

botbuilder-core>=4.4.0b1 ,botbuilder-dialogs>=4.4.0b1 save and close the file.

In the tab, view header click the “Create virtual environment” and create the environment

Create a virtual environment,

The virtual environment was created successfully.

For conformation check the module name displayed in the solution explorer in the ("Env") area.

Our Project template changes are done. Next, I am going to change the code files

Code changes

Delete the default route function

Goto app.py file

Delete the hello() : function including app.route

@app.route('/')
def hello():
"""Renders a sample page."""
return "Hello World!"

Port number update ( optional changes)

goto __main__ function and change the port number

if __name__ == '__main__':
import os
HOST = os.environ.get('SERVER_HOST', 'localhost')
try:
PORT = int(os.environ.get('SERVER_PORT', '5555'))
except ValueError:
PORT = 5555
app.run(HOST, PORT)

Delete the PORT = int(os.environ.get('SERVER_PORT', '5555')) line and hardcode the port value otherwise every time you run the application anew port will be created, here I am using default bot framework port “PORT = 3978”

After changes the code looks like below:

if __name__ == '__main__':
import os
HOST = os.environ.get('SERVER_HOST', 'localhost')
try:
PORT = 3978
except ValueError:
PORT = 5555
app.run(HOST, PORT)

Create on_turn function handling the IO operation.

Create a new Python class file (ex: file name is: “echobot.py”). Add the new class “EchoBot”, this class adds the on_turn function. This function has two arguments

Self, ref the current object
“context” object, This object handles the activity details.

In this sample, we are reading the string which is sent by the user and sends back to the user the same string with the length of string.

from sys import exit
class EchoBot:
async def on_turn(self, context):
if context.activity.type == "message" and context.activity.text:
strlen = len(context.activity.text)
sendInfo = "Hey you send text : " + context.activity.text + " and the lenght of the string is " + str(strlen)
await context.send_activity(sendInfo)

asyn/await concept

Go to the “app.py” and add “import asyncio”, this has supported the async/await concept and "import sys" provides the information about constants, functions, and methods.

import asyncio
import sys

Request and Response module

Add the request and response module in flask module.

from flask import Flask, request, Response

Bot Framework module

Import the BotFrameworkAdapter, BotFrameworkAdapterSettings, TurnContext from botbuilder.core to handle the Bot related queries.

from botbuilder.core import (
BotFrameworkAdapter,
BotFrameworkAdapterSettings,
TurnContext,
)

Import the Activity from botbuilder.schema,

from botbuilder.schema import Activity

Add the EchoBot class in the app.py file to handle the activity type,

from echobot import*

Object creation

Create the object for Echobot class and

bot = EchoBot()
SETTINGS = BotFrameworkAdapterSettings("","")
ADAPTER = BotFrameworkAdapter(SETTINGS)

Create an object for event loop, when called from a coroutine or a callback, this function will always return the running event loop.

LOOP = asyncio.get_event_loop()

Message handler function

This function is the heart of our application, and it handles all the requests and responses. Receiving the information from the request object as a JSON format and call the "await bot.on_turn(turn_context)" pass the turn_context as an argument.

In on_turn function we are checking the activity type. If its type is message, find the length of the string and send the information to the user using context.send_activity function.

@app.route("/api/messages", methods=["POST"])
def messages():
if "application/json" in request.headers["Content-Type"]:
body = request.json
else:
return Response(status=415)
activity = Activity().deserialize(body)
auth_header = (
request.headers["Authorization"] if "Authorization" in request.headers else ""
)
async def aux_func(turn_context):
await bot.on_turn(turn_context)
try:
task = LOOP.create_task(
ADAPTER.process_activity(activity, auth_header, aux_func)
)
LOOP.run_until_complete(task)
return Response(status=201)
except Exception as exception:
raise exception

That's it -- all the changes are done. Rebuild and run the application.

Testing Steps

Open the bot emulator and connect to the URL (http://localhost:3978/api/messages).
Once it is connected, send the message
Bot response to the channel and the information display in the emulator.

Output

Please find the source from here

Conclusion

I hope you can understand the concept of how to create a bot application using Python. More articles are coming soon in Python languages, stay tuned.

Happy reading!!! Happy coding!!!

7 Comments

Join the conversation! Your thoughts help the community grow.

Swapnil Kadam6y ago
Adding to the Below Comment ..I followed all the Steps and the code runs on random port rather than running 3978. When i update the resulting Endpoint in Bot emulator..the Bot doesnt respond....Can you help me where am i doing it wrong?..Let me know if you want to have a look at my code...
- Swapnil Kadam6y ago
  Hi Vinoth..I guess i got to know where the issues was...I corrected it and it works fine..Thanks Again..If there is any question related to other Stuff based on your video tutorials can i ask them here?Once Again Amazing Work..I look forward for more videos/Articles from you
- Swapnil Kadam6y ago
  Hi Vinoth, You can find the code here uploaded in the comment: https://www.c-sharpcorner.com/forums/microsoft-bot-framework-using-python .. Let me know where else can i share the code
- Vinoth Rajendran6y ago
  Share your github path
Swapnil Kadam6y ago
Hi Firstly, Amazing Article and Amazing video on YouTube too..I followed the video on YouTube and all the Concepts were briefly explained..I enjoyed and understood the details that you have used in the code to create the Bot.
Mageshwaran R7y ago
Nice Article