STAC core part one

[uclaros]

Description

This is the first part of the implementation of qgis/QGIS-Enhancement-Proposals#300
It includes the building block classes for parsing and handling STAC elements and allows interacting with STAC catalogs using the QGIS browser.

The contents of both static catalogs and STAC API endpoints can be retrieved using the new STAC root entry on the browser.

STAC Items that contain assets that are cloud optimized (COG, COPC, EPT for now) can be drag and dropped to the map canvas and those assets will be added as layers.

STAC Item assets may be downloaded to a local folder using the Download Assets dialog.

All Catalogs, Collections and Items properties can be examined using the STAC Object Details dialog:

In subsequent PRs the Data Source Manager implementation will be added which will also allow searching for Items and Collections

Any feedback is warmly welcome!

[github-actions]

🪟 Windows builds ready!

Windows builds of this PR are available for testing here. Debug symbols for this build are available here.

(Built from commit d770e55)

[troopa81]

Really happy to see this landing in core, thanks for this work!

Local files reading and blocking network requests in QgsStacController

Could we avoid blocking request and use QgsTask ? I can see no way of canceling (I made a very very quick read of this PR though, I made have skipped it), what happen if I want to close the stac catalog window but QGIS is currently retrieving a lot of items?

[uclaros]

Could we avoid blocking request and use QgsTask ? I can see no way of canceling (I made a very very quick read of this PR though, I made have skipped it), what happen if I want to close the stac catalog window but QGIS is currently retrieving a lot of items?

Blocking requests will only be used for the initial implementation on the browser panel, where QgsDataItem::createChildrent() is always called on a separate thread and there is no concept of closing/canceling in the browser.
The data source manager implementation, which will also support searching, will use async requests which could potentially be cancelled when the data source manager is closed.

[saberraz]

Nice work!
Just a minor comment on UI/UX: in the Browser panel, at the moment, ℹ️ icon is shown for the datasets:

Some datasets do have a preview image. It would be good to use the preview image instead of the ℹ️ icon:

[uclaros]

Some datasets do have a preview image.

The STAC spec suggests to use thumbnail as a role for a quick preview image of the data which should be less than 600x600 pixels. Assets with this role are rendered on top of the Object Details dialog when available.
The overview role may contain large images and is probably more appropriate to actually load as a layer.

In any case, even the thumbnail images may be too big to be used as icons for the DataItems. For me it would make more sense to try and display those thumbnails on the item's tooltips instead.

[wonder-sk]

This looks good to me now

(we have discussed the work with Stefanos extensively, so my earlier comments have been addressed already)

If nobody objects, I would merge this tomorrow...

[github-actions]

🪟 Windows builds

Download Windows builds of this PR for testing.
Debug symbols for this build are available here.
(Built from commit 7b7b6e0)

🪟 Windows Qt6 builds

Download Windows Qt6builds of this PR for testing.
(Built from commit 7b7b6e0)

[qgis-bot]

@uclaros

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