Serve - send an SMS alert

In this part of the tour you'll learn how to create a simple destination. This destination sends an SMS alert to a systems administrator when a CPU spike data frame arrives.

Prerequisites

If you've completed this tutorial so far, you should have all the prerequisites already installed.

Optionally: You can sign up for a free Vonage account, to be able to send an SMS. If you would like to try this, simply set SEND_SMS = True in the main.py code you create later, to switch this feature on.

Create the destination

To create the SMS alert destination:

In your Develop environment, click on Code Samples in the main left-hand navigation.
Select the Python, Destination, and Basic templates filters.
For Starter destination click Preview code.
Click Edit code.
Name the destination "CPU Alert SMS".
Select the input topic cpu-spike.
In the project view click on main.py to edit it.

Replace all the code in main.py with the following:

from quixstreams import Application
import os

# Set this to True if you want to actually send an SMS (you'll need a free Vonage account)
SEND_SMS = False 

if SEND_SMS:
    # Configure Vonage API
    # add vonage module to requirements.txt to pip install it
    import vonage 
    vonage_key = os.environ["VONAGE_API_KEY"]
    vonage_secret = os.environ["VONAGE_API_SECRET"]
    to_number = os.environ["TO_NUMBER"]

    client = vonage.Client(key=vonage_key, secret=vonage_secret)
    sms = vonage.Sms(client)

def send_sms(message):
    """
    Send an SMS using Vonage API
    """
    print("Sending SMS message to admin...")
    response_data = sms.send_message(
        {
            "from": "Vonage APIs",
            "to": to_number,
            "text": message,
        }
    )

    if response_data["messages"][0]["status"] == "0":
        print("Message sent successfully.")
    else:
        print(f"Message failed with error: {response_data['messages'][0]['error-text']}")
    return

def send_alert(row):
    """
    Trigger a CPU spike alert and send an SMS notification
    """
    if SEND_SMS:
        send_sms(row)

# Create an Application
# It will get the SDK token from environment variables to connect to Quix Kafka
app = Application()

# Define an input topic
input_topic = app.topic(os.environ["input"])

# Create a StreamingDataFrame to process data
sdf = app.dataframe(input_topic)

# Trigger the "send_alert" function for each incoming message
sdf = sdf.update(send_alert)

# Print messages to the console
sdf = sdf.update(lambda row: print(row))

if __name__ == "__main__":
    # Run the Application
    app.run(sdf)

Send an SMS (optional)

This section is optional.

If you want to send an alert SMS follow these steps:

Change the variable SEND_SMS to True in your main.py.
In the Environment variables panel, click + Add. The Add Variable dialog is displayed.
Complete the information for the following environment variables (you obtain these from your Vonage developer dashboard):

Variable name Variable type

VONAGE_API_KEY secret

VONAGE_API_SECRET secret

TO_NUMBER secret

See also how to add environment variables.
You now need to add the vonage module to the requirements.txt file in your project. Click to open it and add a line for vonage. This ensures the module is built into the deployment.

Tag and deploy your SMS alert service

You can now tag and deploy your code:

Tag the project as sms-v1 and deploy as a service (watch the video if you're not sure how to do this).
Monitor the logs for the deployed process.

Generate an alert

Again generate a CPU spike by opening several large applications on your laptop. If you have SMS alert enabled, you'll receive an SMS. If not, you can check the logs.

Conclusion

You've now completed the Quix Tour. You've built a simple but complete stream processing pipeline. You can resuse the transform code, with some modifications, in your own projects. With a small amount of work, the SMS service you created could be turned into a general purpose SMS alaerting module, using the Vonage APIs. It could also be adapted to build out other alerting services, such as PagerDuty.

Next steps

To continue your Quix learning journey, you may want to consider some of the following resources:

Variable name	Variable type
VONAGE_API_KEY	`secret`
VONAGE_API_SECRET	`secret`
TO_NUMBER	`secret`