Set up a Local SMS environment with ngrok

Overview

In this tutorial, we will show you a quick way to receive inbound messages on your SMS-enabled Flowroute number using ngrok and Python's web framework, Flask. ngrok is great for local development when you are not ready to:

• set up a web server
• mess with DNS
• deploy your code to production

In order to test Flowroute's inbound SMS quickly, we will use ngrok to create a tunnel to your localhost, and run an example Flask app that will let you receive an SMS on your Flowroute number.

• An activated Flowoute account
• A Flowroute phone number
• Python 2.6 or newer
• Flask framework
• json module
• ngrok

1. Set up ngrok and establish a secure tunnel

If you haven't downloaded and installed ngrok on your local machine, here's the link again. Open a command shell session and run ngrok on port 8080 to work with our Flask app settings.

ngrok http 8080
                

2. Set up and run example Flask application

Copy and paste the following Python script into your text editor of choice. Make sure there aren't any extra tabs or spaces to avoid errors.

Example Flask App

from flask import Flask, request
import json

app = Flask(__name__)
app.debug = True


@app.route('/inboundsms', methods=['POST'])
def inboundsms():
    json_content = request.json
    print json.dumps(json_content)
    return "OK"

if __name__ == '__main__':
    app.run(
        host="0.0.0.0",
        port=int("8080")
    )

            

Save the above as inbound_sms.py. Next, open another command shell window or tab and run the file.

python path_to_file/inbound_sms.py
            

3. Configure inbound SMS for your new ngrok tunnel

Note that we have registered our route as /inboundsms. Copy the forwarding URL from your ngrok session and the app route into the SMS Callback field of your Manage account.

Example SMS Callback

http://5eccb41a.ngrok.io/inboundsms
            

4. Access ngrok web interface for debugging

5. Text your Flowroute phone number

1. Select a phone number on the Manage your DIDs tab.
2. Send a test SMS from your mobile phone to the Flowroute number you have selected.

Potential Errors

A typical error that you might encounter is a 404 Not Found. This usually occurs when the SMS Callback isn't set up correctly.

Additional Resources

Here are some additional reading materials that might be useful for you.

• Receive Inbound SMS Messages with Slack
• Flask Deployment Options