Drawing Bounding boxes and returning only the tiles within the boundary

[sanjana-08]

Im trying to build an application that serves gridded data from Azure Cosmos DB on a map using Martin tile server. I want to be able to include a functionality where you can draw a bounding box and the server will only display the tiles withing that boundary.

I have tried including a SQL function where it creates a TILE envelope but keepe running in this error

Auto-publishing functions in schemas [public] as '{function}' sources Unable to configure source because schema 'public' was not found.

My SQL function is

CREATE OR REPLACE FUNCTION public.function_grid_cells_bbox( 
  z integer, 
  x integer,
  y integer,
  p_xmin double precision,
  p_ymin double precision,
  p_xmax double precision,
  p_ymax double precision
)
RETURNS TABLE (mvt bytea, etag text)
LANGUAGE plpgsql
AS $$
BEGIN
  RETURN QUERY
  SELECT
    ST_AsMVT(tile, 'grid_cells_bbox', 4096, 'geom') AS mvt,
    md5(p_xmin || ',' || p_ymin || ',' || p_xmax || ',' || p_ymax) AS etag
  FROM (
    SELECT
      g.gid,
      ST_AsMVTGeom(
        g.geom,
        ST_TileEnvelope(z, x, y),
        extent => 4096,
        buffer => 64,
        clip_geom => true
      ) AS geom
    FROM public.grid_panel_copy AS g
    WHERE g.geom && ST_Transform(ST_MakeEnvelope(p_xmin, p_ymin, p_xmax, p_ymax, 4326), 3857)
      AND ST_Intersects(
        g.geom,
        ST_Transform(ST_MakeEnvelope(p_xmin, p_ymin, p_xmax, p_ymax, 4326), 3857)
      )
  ) AS tile;
END;
$$;

Is there a better way to go about this?

[CommanderStorm]

Auto-publishing functions in schemas [public] as '{function}' sources Unable to configure source because schema 'public' was not found.

Absolutely no clue why we think no public schema exists.
Could be a misleading error message, hard to debug from my end.

CREATE OR REPLACE FUNCTION public.function_grid_cells_bbox(
z integer,
x integer,
y integer,
p_xmin double precision

We don't currently support this kind of a function.
Please wrap everything in a json object as documented

https://maplibre.org/martin/sources-pg-functions.html