How do I create partitions for only business days?

[clairelin135]

DailyPartitionsDefinitions select every day as a partition. How do I select only the business days?

[clairelin135]

There are a couple options for creating partitions on business days:

1. Create a TimeWindowPartitionsDefinition with a cron schedule of 0 0 * * 1-5, which creates a partition for Monday through Friday at 00:00.
2. The approach above works if all Monday through Friday days are valid. But if you want to take holidays into account too, you can define a DynamicPartitionsDefinition (currently experimental) and create a partition for each business day. For example:

business_days = DynamicPartitionsDefinition(name="business_days")


@op
def add_business_day_partition(context):
    yesterday = date.today() - timedelta(days=1)
    if is_business_day(yesterday):
        context.instance.add_dynamic_partitions(business_days.name, [yesterday.strftime("%Y-%m-%d")])


@job(partitions_def=DailyPartitionsDefinition("2023-01-01"))
def add_business_day_partition_job():
    add_business_day_partition()

defs = Definitions(
    schedules=[
        build_schedule_from_partitioned_job(add_business_day_partition_job),
    ],
)

[rprechelt]

@clairelin135 When using your DynamicPartitionsDefinition method above, the partition shows up as a "StaticPartition" in the DagsterUI when viewing partitions and materializing assets, i.e. you lose the "date/time selector" which has useful "drag and select" in the DagsterUI.

Is it possible to use a unique set of datetime periods (e.g. only business days, or only certain hours on certain) that the user provides but preserve the "date/time selector" in the DagsterUI?