https://github.com/rguske/kn-ps-cloudevent-slack
Example Knative PowerShell function for sending a custom CloudEvent to a Slack webhook.
https://github.com/rguske/kn-ps-cloudevent-slack
eventdriven eventing faas functions knative knative-eventing kubernetes
Last synced: about 1 month ago
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Example Knative PowerShell function for sending a custom CloudEvent to a Slack webhook.
- Host: GitHub
- URL: https://github.com/rguske/kn-ps-cloudevent-slack
- Owner: rguske
- Created: 2023-09-13T13:23:18.000Z (over 1 year ago)
- Default Branch: main
- Last Pushed: 2023-09-15T10:32:19.000Z (over 1 year ago)
- Last Synced: 2025-02-13T17:51:48.483Z (3 months ago)
- Topics: eventdriven, eventing, faas, functions, knative, knative-eventing, kubernetes
- Language: PowerShell
- Homepage:
- Size: 1.12 MB
- Stars: 0
- Watchers: 1
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
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README
# kn-ps-cloudevent-slack
Example Knative PowerShell function for sending a custom CloudEvent to a Slack webhook. This function relies on the Knative [kn-py-cloudevent-transformation-function](https://github.com/rguske/kn-py-cloudevent-transformation-function) which is a requirement for this example.
# Step 1 - Build
Create the container image locally to test your function logic. Change the IMAGE name accordingly, example below for Docker.
```console
export IMAGE=/kn-ps-cloudevent-slack:1.0
docker build -t ${IMAGE}
```
# Step 2 - Test
Verify the container image works by executing it locally.
Change into the `test` directory
```console
cd test
```
Update the following variable names within the `docker-test-env-variable` file
* SLACK_WEBHOOK_URL - Slack webhook URL
* SLACK_MESSAGE_PRETEXT - Text displayed for Slack notification
Start the container image by running the following command:
```console
docker run -e FUNCTION_DEBUG=true -e PORT=8080 --env-file docker-test-env-variable -it --rm -p 8080:8080 ${IMAGE}
```
In a separate terminal, run either `send-cloudevent-test.ps1` (PowerShell Script) or `send-cloudevent-test.sh` (Bash Script) to simulate a CloudEvent payload being sent to the local container image
```console
Testing Function ...
See docker container console for output
# Output from docker container console
06/27/2022 09:47:31 - DEBUG: K8s Secrets:
{"SLACK_WEBHOOK_URL":"**********","SLACK_MESSAGE_PRETEXT":"Slack :knative: Function"}
06/27/2022 09:47:31 - DEBUG: "{
attachments = @(
@{
pretext = $(${jsonSecrets}.SLACK_MESSAGE_PRETEXT);
fields = @(
@{
title = "Event Type";
value = $cloudEvent.type;
short = "false";
}
@{
title = "Unique ID";
value = $cloudEvent.id;
short = "false";
}
@{
title = "DateTime in UTC";
value = $cloudEvent.time;
short = "false";
}
@{
title = "Source";
value = $cloudEvent.source;
short = "false";
}
@{
title = "Event";
value = $cloudEventData.actuator.event.organization;
short = "false";
}
@{
title = "Attendee Mood";
value = $cloudEventData.example.attendee.mood;
short = "false";
}
@{
title = "Next-up";
value = $cloudEventData.next.up;
short = "false";
}
)
footer = "Powered by Knative";
footer_icon = "https://github.com/knative/docs/blob/main/docs/images/logo/cmyk/knative-logo-cmyk.png";
}
)
}
"
06/27/2022 09:47:31 - Sending Webhook payload to Slack ...
06/27/2022 09:47:31 - Successfully sent Webhook ...
```
# Step 3 - Deploy
> **Note:** The following steps assume a working Knative environment using the RabbitMQ or the `MTChannelBasedBroker` broker. The Knative `service` and `trigger` will be installed in the
`vmware-functions` Kubernetes namespace, assuming that the `broker` is also available there.
>
> **Note:** Also, in order to receive incoming events and to ultimately invoke the kn-ps-cloudevent-slack function, it's necessary to have the [ kn-ps-cloudevent-slack](https://github.com/rguske/kn-py-cloudevent-transformation-function) running first.
Update the `cloudevent_slack_secret.json` file with your Slack webhook configurations and then create the Kubernetes secret which can then be accessed from within the function by using the environment variable named called `SLACK_SECRET`.
```console
# create secret
kubectl -n vmware-functions create secret generic cloudevent-slack-secret --from-file=SLACK_SECRET=cloudevent_slack_secret.json
```
Edit the `function.yaml` file with the name of the container image from Step 1 if you made any changes. If not, the default VMware container image will suffice. By default, the function deployment will filter on the `my.very.own.cloudevent.created.v0` ASOP event. If you wish to change this, update the `type` field within `function.yaml` to the desired event type.
Furthermore, use the Sockeye Event viewer to display all incoming events.
Deploy the function to the Knative environment.
```console
# deploy function
kubectl -n vmware-functions apply -f function.yaml
```
For testing purposes, the `function.yaml` contains the following annotations, which will ensure the Knative Service Pod will always run **exactly** one instance for debugging purposes.
```yaml
annotations:
autoscaling.knative.dev/maxScale: "1"
autoscaling.knative.dev/minScale: "1"
```
# Step 4 - Undeploy
```console
# undeploy function
kubectl -n vmware-functions delete -f function.yaml
# delete secret
kubectl -n vmware-functions delete secret asop-slack-secret
```