Closed
Description
Hi everyone!
I've added default ordering to resource attributes (yaml). So far so good.
However, the default order is still applied when querying the collection with an explicit order filter (query param).
The query builder used by data provider orders by default and by order filter.
Is there a way to ditch default order when order filter has been activated?
Also is it possible to define default order at operation level?
Activity
teohhanhui commentedon Apr 5, 2019
The default order is used to ensure a stable ordering of items, as otherwise the order is undefined as per the SQL standard. I don't see any case where you should have a need to remove the default order when using custom ordering.
teohhanhui commentedon Apr 5, 2019
It does not seem to be supported at this time: https://github.com/api-platform/core/blob/v2.4.2/src/Bridge/Doctrine/Orm/Extension/OrderExtension.php#L54
But indeed we could.Actually we shouldn't, as it makes no sense.tezvi commentedon Apr 5, 2019
Let me put it this way. The user should be able to order collection by using a specific order filter. If no filter is used the collection should be ordered by default order.
It seems I cannot recreate that with the current implementation.
teohhanhui commentedon Apr 5, 2019
Sorry, I don't understand. The default order is exactly what that's for? I've already explained above why the default order is always added to the end. You should choose something that is definitely able to order items to avoid running into undefined ordering.
To give you an example, if the user chooses to order by
name
, what happens when 2 items have the samename
? That's the job of the default order (say, order byid
), to make sure that the order is deterministic.teohhanhui commentedon Apr 5, 2019
In fact, the default order is not used by the
OrderFilter
(which is applied by theFilterExtension
), but by theOrderExtension
. Perhaps that's the source of your confusion. It should probably be renamed theDefaultOrderExtension
(default_order
in metadata attributes). 😄teohhanhui commentedon Apr 5, 2019
Keeping open for this.
tezvi commentedon Apr 5, 2019
Hi teohhanhui,
thanks for your input and clarification. I understand the difference between OrderExtension and FilterExtension. However, I'm not really sure if we have an understanding. Let's assume we have a simple entity, just for the sake of example.
ApiPlatform resource definition:
Filter service
when querying /api/bars API endpoint the api_platform data provider would generate something like this (approximation, writing from top of my head)
SELECT * FROM bars ORDER BY code ASC, id DESC
When querying /api/bars?order[name]=asc&order[description]=desc the query would look like this (not really sure about order of ORDER clause identifiers):
SELECT * FROM bars ORDER BY code ASC, id DESC, name ASC, description DESC
or
SELECT * FROM bars ORDER BY name ASC, description DESC, code ASC, id DESC
Either way, default order is unnecessary applied. For huge tables this would present an overhead at database level and eventually wrong ordering.
Sorry if I make this unnecessary difficult or if I don't see a solution out-of-the-box.
A potential solution that does not touch any api-platform implementation is to decorate OrderExtension and detect if order filter is being activated, before or after the OrderFilter is processed.
tezvi commentedon May 20, 2019
If anyone stumbles upon the same problem this gist has the solution mentioned in previous post.
https://gist.github.com/tezvi/d0974664a423a3052518bfb47bac672c
8 remaining items