Knative and Camel-K Telegram Translate Bot Example

This demo converts Telegram messages into English using Camel-K and Knative functions.

It uses a Camel-K Kamelet to periodically poll Telegram for messages. The Kamelet converts each message into a CloudEvent, sending it to the default Knative Broker. A translate function receives these events via a Trigger between the Broker and the function which filters for these types of events.

The translate function uses the Google Translation API is used to convert the message text to English, and the result is returned to the broker as data in a new translation CloudEvent.

The broker has two additional triggers that respond to these translation events. One forwards the event to a viewer function, which simply displays the event on the console so that we can see if things are behaving as expected. The other trigger sends the event to a responder function, which responds to the message in the Telegram chat with the translation.

Prerequisites

• A cluster with Knative installed
• CamelK https://camel.apache.org/camel-k/1.9.x/installation/installation.html installed
• Google Translation API key in translate/service-account-file.json
• Update the Telegram API key in ./resources/telegram-binding-v1.yaml

Steps

• Ensure your Google Translation API key is correctly set in translate/service-account-file.json
• Create a Kubernetes secret containing your Telegram API key

kubectl create secret generic telegram --from-literal=API_KEY=<apikey>

• Install a default Knative Broker

kn broker create default

• Deploy the functions

func deploy -p viewer
func deploy -p translate
func deploy -p responder

• Create the Telegram->Translate trigger

kn trigger create telegram-trigger -s translate --filter type=telegram.source

• Create the Translation->Viewer trigger

kn trigger create translate-trigger -s viewer --filter type=knative.function.translation

• Create the Translation->Responder trigger

kn trigger create responder-trigger -s responder --filter type=knative.function.translation

• Install the Kamelet

kubectl apply -f resources/telegram-binding-v1.yaml

• Send a Telegram message to your bot channel

• Check the logs

k logs -l app=viewer -f
k logs -l app=responder -f
k logs -l app=translate -f

• Cleanup

./resources/teardown.sh