README.md

Bind a Service to a Lambda Function

Overview

This example shows how to bind lambda functions to a service. A lambda function connects to a Redis instance and retrieves statistics for this service.

The example covers these tasks:

1. Create a Redis instance.
2. Create a function using Kubeless CLI.
3. Bind the function to the Redis Service.
4. Call the lambda function.

Prerequisites

• Install the Kubeless CLI as described in the Kubeless installation guide.
• A Namespace to which you deploy the example with the env: "true" label. For more information, read the related documentation.

Installation

Apply a battery of yaml files to run the example.

Steps

1. Export your Namespace as a variable by replacing the {namespace} placeholder in the following command and running it:

   export KYMA_EXAMPLE_NS="{namespace}"

2. Create a Redis instance:

   kubectl apply -f deployment/redis-instance.yaml -n $KYMA_EXAMPLE_NS

3. Ensure that the Redis instance is provisioned:

   kubectl get serviceinstance/redis-instance -o jsonpath='{ .status.conditions[0].reason }' -n $KYMA_EXAMPLE_NS

4. Create a Redis client through a lambda function, along with the ServiceBinding, and the ServiceBindingUsage custom resource:

   kubectl apply -f deployment/lambda-function.yaml -n $KYMA_EXAMPLE_NS

5. Ensure that the Redis ServiceBinding works:

   kubectl get servicebinding/redis-instance-binding -o jsonpath='{ .status.conditions[0].reason }' -n $KYMA_EXAMPLE_NS

6. Verify that the lambda function is ready:

   kubeless function ls redis-client -n $KYMA_EXAMPLE_NS

7. Trigger the function. The information and statistics about the Redis server appear in the logs of the function Pod.

   kubeless function call redis-client -n $KYMA_EXAMPLE_NS

Cleanup

Use this command to remove the example and all its resources from your Kyma cluster:

kubectl delete all,function,servicebinding,serviceinstance,servicebindingusage -l example=service-binding -n $KYMA_EXAMPLE_NS

Troubleshooting

Make sure the password is injected correctly into the Pod. The password should match the one in the redis-instance.yaml

kubectl exec -n $KYMA_EXAMPLE_NS -it $(kubectl get po -n $KYMA_EXAMPLE_NS -l example=service-binding --no-headers | awk '{print $1}') bash

env | grep -i redis_password