Zappa is a very lightweight and powerful tool which allows you to deploy and update python applications to AWS. Using Zappa you can host your WSGI app on AWS Lambda, API Gateway quickly.

Generally, we prefer to use a VM to host our python application and the VM is costly compared to serverless technology because it will be up and running all the time and the cloud provider is billing us as per run time. Pricing based on the amount of computing power, storage, and time.

• Infinite scaling
• Zero downtime
• Zero maintenance

Nowadays serverless is in a buzz. Actually without any server we can’t host our application there is a resource which is available on demand. "Serverless computing is a cloud computing execution model in which the cloud provider allocates machine resources on demand, taking care of the servers on behalf of their customers."

AWS EC2 is a service that provides traditional cloud infrastructure (IaaS) and allows us to run EC2 instances as VMs. AWS Lambda provides us a serverless architecture and allows you to run arbitrary event-driven code in the cloud after an event trigger is activated.

There are many alternatives available for Zappa :

• Serverless
• Apex

Step 1 : Create a project folder called “myflask".
  > mkdir myflask 

Step 2 : Create a “requirements.txt” file inside of the myflask folder.
 Flask==2.0.1 
 zappa==0.48.2  

Step 3 : Create Virtual Environment
 >virtualenv env 

Step 4 : Activate Your env
  (Windows) D:\zappaTest>env\Scripts\activate 
 (Mac) $ source env/bin/activate 

Step 5 : Install Dependencies in Environment
  (env)> pip3 install -r requirements.txt  

Step 6 : Create an index.py file for Flask.

                               
									from flask import Flask
									app = Flask(__name__)


									@app.route('/')
									def hello_world():
									   return 'Hello, World!'

									@app.route('/hello')
									def hello_world1():
									   return 'Hello, World1!'


									if __name__ == '__main__':
									   app.run(host="0.0.0.0", port=3000, debug=True)

                                
                            

Step 7 : Test Flask
 (env)> python3 index.py 

Step 8 : Create a Zappa configuration file.
  (env)> zappa init  
 (read all instructions) 

                               
									{
										"dev": {
											"aws_region": "ap-south-1",
											"django_settings": "myproject.settings",
											"profile_name": "default",
											"project_name": "project",
											"runtime": "python3.6",
											"s3_bucket": "zappa-ga67u69nx"
										}
									}
                                
                            

Step 9 : Setup your aws configure There is two ways to configure your aws credentials using AWS command or updating credentials file if you want to go with command then you must have awscli installed into your local machine if not install using
> pip3 install awscli
> aws configure 
 AWS Access Key ID [None]: AKIAIOSFODNN7EXAMPLE 
 AWS Secret Access Key [None]: wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY 
 Default region name [None]: us-west-2 
 Default output format [None]: json 

OR
 > vi ~/.aws/credentials 
 [default]
 aws_access_key_id = 'abc' 
 aws_secret_access_key = '123’ 

Step 10 : Deploy Flask
 (env)>zappa deploy  
or
 (env)>zappa deploy 

Step 11: After Deploying Check Server Log
 (env)D:\zappaTest>zappa tail 

Step 12: Update Codebase
 (env)D:\zappaTest>zappa update dev 

Step 13: If you want to remove this project from aws
  (env)D:\zappaTest>zappa undeploy  
or
 (env)D:\zappaTest>zappa undeploy