openfunction

Description

The openfunction Plugin is used to integrate APISIX with CNCF OpenFunction serverless platform.

This Plugin can be configured on a Route and requests will be sent to the configured OpenFunction API endpoint as the upstream.

Attributes

note

The timeout attribute sets the time taken by the OpenFunction to execute, and the timeout for the HTTP client in APISIX. OpenFunction calls may take time to pull the runtime image and start the container. So, if the value is set too small, it may cause a large number of requests to fail.

Prerequisites

Before configuring the plugin, you need to have OpenFunction running. Installation of OpenFunction requires a certain version Kubernetes cluster. For details, please refer to Installation.

Create and Push a Function

You can then create a function following the sample

You’ll need to push your function container image to a container registry like Docker Hub or Quay.io when building a function. To do that, you’ll need to generate a secret for your container registry first.

REGISTRY_SERVER=https://index.docker.io/v1/ REGISTRY_USER= ${your_registry_user} REGISTRY_PASSWORD= ${your_registry_password}
kubectl create secret docker-registry push-secret \
    --docker-server=$REGISTRY_SERVER \
    --docker-username=$REGISTRY_USER \
    --docker-password=$REGISTRY_PASSWORD

Enable the Plugin

You can now configure the Plugin on a specific Route and point to this running OpenFunction service:

note

You can fetch the admin_key from config.yaml and save to an environment variable with the following command:

admin_key=$(yq '.deployment.admin.admin_key[0].key' conf/config.yaml | sed 's/"//g')

curl http://127.0.0.1:9180/apisix/admin/routes/1 -H "X-API-KEY: $admin_key" -X PUT -d '
{
    "uri": "/hello",
    "plugins": {
        "openfunction": {
            "function_uri": "http://localhost:3233/default/function-sample/test",
            "authorization": {
                "service_token": "test:test"
            }
        }
    }
}'

Example usage

Once you have configured the plugin, you can send a request to the Route and it will invoke the configured function:

curl -i http://127.0.0.1:9080/hello

This will give back the response from the function:

hello, test!

Configure Path Transforming

The OpenFunction Plugin also supports transforming the URL path while proxying requests to the OpenFunction API endpoints. Extensions to the base request path get appended to the function_uri specified in the Plugin configuration.

IMPORTANT

The uri configured on a Route must end with * for this feature to work properly. APISIX Routes are matched strictly and the * implies that any subpath to this URI would be matched to the same Route.

The example below configures this feature:

curl http://127.0.0.1:9180/apisix/admin/routes/1 -H "X-API-KEY: $admin_key" -X PUT -d '
{
    "uri": "/hello/*",
    "plugins": {
        "openfunction": {
            "function_uri": "http://localhost:3233/default/function-sample",
            "authorization": {
                "service_token": "test:test"
            }
        }
    }
}'

Now, any requests to the path hello/123 will invoke the OpenFunction, and the added path is forwarded:

curl  http://127.0.0.1:9080/hello/123

Hello, 123!

Delete Plugin

To remove the openfunction Plugin, you can delete the corresponding JSON configuration from the Plugin configuration. APISIX will automatically reload and you do not have to restart for this to take effect.

curl http://127.0.0.1:9180/apisix/admin/routes/1  -H "X-API-KEY: $admin_key" -X PUT -d '
{
    "methods": ["GET"],
    "uri": "/index.html",
    "upstream": {
        "type": "roundrobin",
        "nodes": {
            "127.0.0.1:1980": 1
        }
    }
}'