Feature Collection as output

[fabricebrito]

@rconway in commit 4de092c you introduced pystac.ItemCollection as output.

What is the rational?

[rconway]

@fabricebrito
This commit did not introduce the ItemCollection as output - this was already the case before the commit...

• BEFORE - 4de092c#diff-ff92bc281255f901080e4a4dabb6ecca853909ede8cf01bca6a05d3249a529dcL361
• AFTER - 4de092c#diff-ff92bc281255f901080e4a4dabb6ecca853909ede8cf01bca6a05d3249a529dcR398

The goal of this commit was regarding the stage-out S3 location - with additional logic to either use the workspace storage or to fall back to the S3 details provided by the passed in environment variables...

• 4de092c#diff-ff92bc281255f901080e4a4dabb6ecca853909ede8cf01bca6a05d3249a529dcR121

Looks like the ItemCollection fix was initiated here - c51772d

I think this was an attempt to 'make it work' during integration - i.e. the stageout was failing with exceptions and this solved the exceptions. It was trying to be equivalent to what was there before - i.e. not change behaviour.

Note that the return of the feature_collection goes back before these fixes -

eoepca-proc-service-template/{{cookiecutter.service_name}}/service.py

Line 318 in 8bb4883

outputs["stac"]["value"] = execution_handler.feature_collection

The origin seems to be here - dd435f1#diff-ff92bc281255f901080e4a4dabb6ecca853909ede8cf01bca6a05d3249a529dcR368

[fabricebrito]

The origin seems to be here - dd435f1#diff-ff92bc281255f901080e4a4dabb6ecca853909ede8cf01bca6a05d3249a529dcR368

This actually returns the URL of the collection while your commits provide an inline feature collection and this is what I wanted to understand.

I've implemented the same approach here: https://github.com/eoap/zoo-service-template/blob/b6144a91781092c3b83b3e29034ed39ac27c759f/%7B%7Bcookiecutter.service_name%7D%7D/service.py#L104-L155 (in the context of the https://github.com/eoap/ogc-api-processes-with-zoo/ e-learning module)

client wise it's quite easy to consume/understand the results but was wondering about the rationale behind this approach

[rconway]

I don't think there was a rationale. More likely a misunderstanding of what was being returned in the first place.

Is this not returning a Collection (json) rather than a URL...

self.feature_collection = requests.get(f"https://workspace-api.{self.domain}/workspaces/{self.workspace_prefix}-{decoded['user_name']}/collections/{collection.id}", headers=headers).json()

[rconway]

Perhaps the real question is what should be returned - e.g. according to the standard / best practice?