Apache OpenWhisk AMQP Event Provider

This is an Apache OpenWhisk trigger feed for an AMQP provider (e.g. RabbitMQ). Messages arriving on a queue are fired as trigger events. Messages are processed one at a time, i.e. the next trigger won't be fired until the last message have been processed.

usage

| Entity | Type | Parameters | | ------------------------------------------ | ---- | ------------------------------------- | | /<PROVIDER_NS>/amqp-trigger-feed/changes | feed | url, queue, format, cert, cert_format |

• url is the full AMQP URL for the broker, e.g. amqp(s)://user:[email protected]:port
  • mandatory parameter
• queue is the queue to listen for messages on. This queue must already exist in the broker.
  • mandatory parameter
• format is the format incoming queue messages should be converted before firing as trigger events.
  • valid values: json, utf-8 & base64
  • default value: utf-8
• cert is the PEM server certificate string.
• cert_format is the PEM server certificate format
  • valid values: utf-8 & base64.
  • default value: utf-8

cli example

wsk trigger create test-amqp-trigger --feed /<PROVIDER_NS>/amqp-trigger-feed/changes --param url <AMQP_URL> --param queue <QUEUE_NAME>

trigger events

Trigger events fired by the provider have a single property (message) which contains the queue message.

{"message":"<QUEUE_MESSAGE>"}

message format

AMQP messages are received as native Node.js buffers. Before firing as trigger events this must be converted to a format suitable for encoding in a JSON message. By default the message contents will be converted to a UTF-8 string. The conversion format can be controlled by setting the format trigger parameter.

Using base64 as the format will encoded the raw Buffer as a Base64 string before firing the trigger event. If json is used as the format, the buffer is converted to a string and parsed as a JSON object.

connecting over ssl

If you need to connect to a AMQP broker over TLS, use the amqp:// URL prefix in the URL parameter.

If the broker uses a self-signed certificate, this will need to be provided in the trigger parameter options. The cert parameter is used to provide the certificate value, which can either be the raw certificate string (-----BEGIN CERTIFICATE-----…) or a base64-encoded version. If you provide a base-64 encoded version, make sure you specify the cert_format parameter to be base64.

errors

If there are any issues with the connection to the broker, the trigger will be automatically disabled. Error details on what has gone wrong are available by retrieving the latest status of the trigger.

wsk trigger get test-amqp-trigger

development

running

See the "Pluggable OpenWhisk Event Provider" docs on how to run this event provider. The following environment parameters are needed for this feed provider.

unit tests

npm test

integration tests

• Create a test/integration/config.json with the following values.

{
  "openwhisk": {
    "apihost": "<OW_HOSTNAME>",
    "api_key": "<OW_KEY>",
    "namespace": "_",
    "trigger": "amqp-trigger-feed-test",
    "rule": "amqp-rule-feed-test"
  },
  "amqp": {
    "url": "<AMQP_BROKER_URL>",
    "queue": "amqp-feed-provider-test"
  }
}

• Run the integration tests

npm run test-integration