dialogflowcx-private-webhook-example

Dialogflow CX - Private Webhook example

Simple Dialogflow CX webhook for demo and troubleshooting purpose. Solution based on FastAPI. Example designed to implement a Dialogflow CX webhook using Service Directory for private network access using a self signed certificate.

The example can be adapted to support external URL and public certificates tweaking the docker-compose configuration.

For local testing purposes, a simple endpoint can be started with the following command:

python3 -m venv env
source env/bin/activate
uvicorn webhook:app --host 0.0.0.0 --port 8081

You can open your browser http://127.0.0.1:8081/docs to check and test your webhook endpoints.

The webhook suports 2 Dialgflow webhook tags:

• Default Welcome Intent: it returns always Hi from a Python Webhook! message
• echo: it returns the sentence sent by the intent in the form of You said: $SENTENCE

Tests

Tests are written using pytest. You can run tests with the following command:

pytest

Project Structure

.
├── modules             # Folder containing Data structure
  ├── request.py        # Data structure definition for Dialogflow webhook request
  ├── resposne.py       # Data structure definition for Dialogflow webhook response
├── docker-compose.yaml # Docker compose YAML configuration to deploy Traefik and Webhook containers
├── Dockerfile          # Dockerfile to define a docker container
├── requirements.txt    # Python requirement file
├── webhook_test.py     # pytest
├── webhook.py          # Main file
 

Architecture

The solution can be deployed on any environment, this demo assumes the following:

• The solution relies on a single GCP project with single project VPC
• The solution runs a GCE instance
• The GCE instance has no public IP
• The GCE instance runs on the same region as the Dialogflow agent

Deployment

Dialogflow CX requires the webhook to support HTTPS requests. The solution is designed to handle requests for host webhook.internal, it relies on a self-signed certificate and it uses Traefik reverse-proxy to handle SSL certificates.

Prerequisites

The following components are present on the GCE instance:

• Openssl
• Docker
• Docker-Compose

Create Self Signed certificates

To create a self-signed certification, run the following command in the certificate folder:

export DOMAIN=webhook.internal

openssl genrsa -out server.key 2048
openssl req -nodes -new -sha256 -newkey rsa:2048 -key server.key -subj "/CN=${DOMAIN}" -out server.csr
openssl x509 -req -days 3650 -sha256 -in server.csr -signkey server.key -out server.crt -extfile <(printf "\nsubjectAltName='DNS:${DOMAIN}'")
openssl x509 -in server.crt -out server.der -outform DER

Run docker-compose

Run docker-compose to deploy your application:

docker-compose up -d

Configure DialogFlow CX Agent

Configure your Dialogflow CX agent:

• Configure the Dialgoflow agent webhook to use Service Directory for private network access.
  • The webhook URL is https://webhook.internal/weebhook.
  • Upload the DER self-signed certificate created.
• Configure the Dialogflow intent to use the configured webhook.

Test your Agent - Webhook interaction

Open the Dialogflow CX Test agent section and trigger the intent you configured.