feat(server): add redirect route to pre-zoomed tileset BM-1076

[tawera-manaena]

Motivation

As an Imagery Data Maintainer, I want a link for each tileset that auto-zooms to its bounding box. This is so I can keep Basemaps URL links short, clean looking, and zoomed to the right spot.

Modifications

1. Added a /v1/link/:tileSet route to the basemaps/lambda-tiler package.
2. Implemented a function to capture and process requests to v1/link/:tileSet.
   • On success, returns a 302 response that redirects the client to a Basemaps URL that is already zoomed to the extent of the tileset's imagery.
   • On failure, returns a 4xx response explaining why the function terminated.

Usage

Enters from...	Status	Redirects to...
/v1/link/ashburton-2023-0.1m	302 Found	/@-43.9157018,171.7712402,z12?i=ashburton-2023-0.1m

Verification

Depending on the size of the user's viewport, there are situations where the pre-zooming estimation may or may not suffice. See each of the following examples for details:

Ashburton 0.1m (2023)

From	To
/link/ashburton-2023-0.1m	/@-43.9157018,171.7712402,z12?i=ashburton-2023-0.1m

The tileset is over-zoomed by a slight amount. But, it's not noticeable.

Christchurch 0.05m (2021)

From	To
/link/christchurch-urban-2021-0.05m	@-43.5286378,172.6309204,z12?i=christchurch-urban-2021-0.05m

The tileset is under-zoomed quite substantially. It seems as though the bounding box itself is much larger than the imagery. The user will have to zoom in themselves.

Otago 0.1m (2018)

From	To
/link/otago-urban-2018-0 1m	/@-45.2516883,169.6289062,z10?i=otago-urban-2018-0.1m

Regions of the tileset are cut off from the viewport. The user will have to zoom out themselves.

[tawera-manaena]

Revisions

Modifications

1. Added a /v1/link/:tileSet route to the basemaps/lambda-tiler package.
2. Implemented a test suite to ensure the endpoint works as expected.

Limitations

1. The endpoint does not allow the user to specify a projection. However, this can easily be added in the future. At the moment, the endpoint only supports tilesets that have EPSG:3857 imagery layers.