Time Filter

Time filter is applied to the event time, contained in the event context. A CloudEvent from Webhook event-source has payload structure as:

{
    "context": {
      "type": "type_of_event_source",
      "specversion": "cloud_events_version",
      "source": "name_of_the_event_source",
      "id": "unique_event_id",
      "time": "event_time",
      "datacontenttype": "type_of_data",
      "subject": "name_of_the_configuration_within_event_source"
    },
    "data": {
      "header": {},
      "body": {},
    }
}

It filters out events occurring outside the specified time range, so it is specially helpful when you need to make sure an event occurs between a certain time-frame.

Fields

Time filter has following fields:

filters:
  time:
    start: time_range_start_utc
    stop: time_range_end_utc

How it works

Time filter takes a start and stop time in HH:MM:SS format in UTC.

apiVersion: argoproj.io/v1alpha1
kind: Sensor
metadata:
  name: with-time-filter
spec:
  template:
    serviceAccountName: operate-workflow-sa
  dependencies:
    - name: test-dep
      eventSourceName: webhook
      eventName: example
      filters:
        time:
          start: "02:30:00"
          stop: "04:30:00"

If stop is smaller than start (stop < start), the stop time is treated as next day of start.

Note: start is inclusive while stop is exclusive.

Time filter behaviour visually explained

1. if start < stop: event time must be in [start, stop).

   00:00:00 00:00:00 00:00:00 ┃ start stop ┃ start stop ┃ ─┸─────●───────────────────────○─────┸─────●───────────────────────○─────┸─ ╰───────── OK ──────────╯ ╰───────── OK ──────────╯

2. if stop < start: event time must be in [start, stop@Next day)
   (this is equivalent to: event time must be in [00:00:00, stop) || [start, 00:00:00@Next day)).

   00:00:00 00:00:00 00:00:00 ┃ stop start ┃ stop start ┃ ─┸───────────○───────────●───────────┸───────────○───────────●───────────┸─ ─── OK ──────╯ ╰───────── OK ──────────╯ ╰────── OK ───

Practical example

1. Create a webhook event-source

   kubectl -n argo-events apply -f https://raw.githubusercontent.com/argoproj/argo-events/stable/examples/event-sources/webhook.yaml
   

2. Create a webhook sensor with time filter

   kubectl -n argo-events apply -f https://raw.githubusercontent.com/argoproj/argo-events/stable/examples/sensors/filter-with-time.yaml
   

3. Send an HTTP request to event-source

   curl -d '{"message":"this is my first webhook"}' -H "Content-Type: application/json" -X POST http://localhost:12000/example
   

4. You will notice one of following behaviours:

   • if you run this example between 02:30 and 04:30, the sensor logs the event is valid
   • if you run this example outside time range between 02:30 and 04:30, the sensor logs the event is invalid

Further examples

You can find some examples here.