Intro

TiTiler.PgSTAC is a TiTiler extension, which create dynamic tiler connected to PgSTAC databases.

By default the main application (titiler.pgstac.main.app) provides three sets of endpoints:

/searches/{search_id}: Dynamic mosaic tiler based on PgSTAC Search Query
/collections/{collection_id}: Dynamic mosaic tiler based on STAC Collection
/collections/{collection_id}/items/{item_id}: Dynamic tiler for single STAC item (stored in PgSTAC)

STAC Searches - `/searches/{search_id}`¶

Register a PgSTAC `Search` request¶

Important

In TiTiler.PgSTAC a STAC Search Query is equivalent to a Virtual Mosaic and a PgSTAC Search Hash is equivalent to a Mosaic Identifier.

Before being able to create Map Tiles, the user needs to register a Search Query within the PgSTAC database (in the searches table). By default, TiTiler.PgSTAC has a /searches/register (POST) endpoint which will:

validate the search query (based on the STAC API specification item-search)
send the search query to the postgres database using the search_query PgSTAC function
return a PgSTAC Search hash

Example

curl -X 'POST' 'http://127.0.0.1:8081/searches/register' \
  -H 'accept: application/json' \
  -H 'Content-Type: application/json' \
  -d '{"collections":["landsat-c2l2-sr"], "bbox":[-123.75,34.30714385628804,-118.125,38.82259097617712], "filter-lang": "cql-json"}' | jq

>> {
  "id": "5a1b82d38d53a5d200273cbada886bd7",
  "links": [
    {
      "rel": "metadata",
      "type": "application/json",
      "href": "http://127.0.0.1:8081/searches/5a1b82d38d53a5d200273cbada886bd7/info"
    },
    {
      "rel": "tilejson",
      "type": "application/json",
      "href": "http://127.0.0.1:8081/searches/5a1b82d38d53a5d200273cbada886bd7/tilejson.json"
    }
  ]
}

# Or using CQL-2
curl -X 'POST' 'http://127.0.0.1:8081/searches/register' \
  -H 'accept: application/json' \
  -H 'Content-Type: application/json' \
  -d '{"filter": {"op": "and", "args": [{"op": "=", "args": [{"property": "collection"}, "landsat-c2l2-sr"]}, {"op": "s_intersects", "args": [{"property": "geometry"}, {"coordinates": [[[-123.75, 34.30714385628804], [-123.75, 38.82259097617712], [-118.125, 38.82259097617712], [-118.125, 34.30714385628804], [-123.75, 34.30714385628804]]], "type": "Polygon"}]}]}}' | jq

>> {
  "id": "5063721f06957d6b2320326d82e90d1e",
  "links": [
    {
      "rel": "metadata",
      "type": "application/json",
      "href": "http://127.0.0.1:8081/searches/5063721f06957d6b2320326d82e90d1e/info"
    },
    {
      "rel": "tilejson",
      "type": "application/json",
      "href": "http://127.0.0.1:8081/searches/5063721f06957d6b2320326d82e90d1e/tilejson.json"
    }
  ]
}

curl http://127.0.0.1:8081/searches/5063721f06957d6b2320326d82e90d1e/info | jq

>> {
  "search": {
    "hash": "5063721f06957d6b2320326d82e90d1e",  # <-- this is the PgSTAC Hash = search/mosaic identifier
    "search": {  # <-- Summary of the search request
      "filter": {  # <-- this is CQL2 filter associated with the search
        "op": "and",
        "args": [
          {
            "op": "=",
            "args": [
              {
                "property": "collection"
              },
              "landsat-c2l2-sr"
            ]
          },
          {
            "op": "s_intersects",
            "args": [
              {
                "property": "geometry"
              },
              {
                "type": "Polygon",
                "coordinates": [
                  [
                    [
                      -123.75,
                      34.30714385628804
                    ],
                    [
                      -123.75,
                      38.82259097617712
                    ],
                    [
                      -118.125,
                      38.82259097617712
                    ],
                    [
                      -118.125,
                      34.30714385628804
                    ],
                    [
                      -123.75,
                      34.30714385628804
                    ]
                  ]
                ]
              }
            ]
          }
        ]
      }
    },
    "_where": "(  ( (collection_id = 'landsat-c2l2-sr') and st_intersects(geometry, '0103000020E610000001000000050000000000000000F05EC055F6687D502741400000000000F05EC02D553EA94A6943400000000000885DC02D553EA94A6943400000000000885DC055F6687D502741400000000000F05EC055F6687D50274140'::geometry) )  )  ",  # <-- internal pgstac WHERE expression
    "orderby": "datetime DESC, id DESC",
    "lastused": "2022-03-03T11:44:55.878504+00:00",  # <-- internal pgstac variable
    "usecount": 2,  # <-- internal pgstac variable
    "metadata": {  # <-- titiler-pgstac Mosaic Metadata
      "type": "mosaic"  # <-- when we use the `/searches/register` endpoint, titiler-pgstac will add `type=mosaic` to the metadata
    }
  },
  "links": [
    {
      "rel": "self",
      "type": "application/json",
      "href": "http://127.0.0.1:8081/searches/5063721f06957d6b2320326d82e90d1e/info"
    },
    {
      "rel": "tilejson",
      "type": "application/json",
      "href": "http://127.0.0.1:8081/searches/5063721f06957d6b2320326d82e90d1e/tilejson.json"
    }
  ]
}

Mosaic Metadata¶

In addition to the search query, a user can pass metadata, which will be saved in the postgres table.

curl -X 'POST' 'http://127.0.0.1:8081/searches/register' \
  -H 'accept: application/json' \
  -H 'Content-Type: application/json' \
  -d '{"collections":["landsat-c2l2-sr"], "bbox":[-123.75,34.30714385628804,-118.125,38.82259097617712], "filter-lang": "cql-json", "metadata": {"minzoom": 8, "maxzoom": 13, "assets": ["B04", "B03", "B02"], "defaults": {"true_color": {"assets": ["B04", "B03", "B02"], "color_formula": "Gamma RGB 3.5 Saturation 1.7 Sigmoidal RGB 15 0.35"}}}}' | jq

>> {
  "id": "f31d7de8a5ddfa3a80b9a9dd06378db1",
  "links": [
    {
      "rel": "metadata",
      "type": "application/json",
      "href": "http://127.0.0.1:8081/searches/f31d7de8a5ddfa3a80b9a9dd06378db1/info"
    },
    {
      "rel": "tilejson",
      "type": "application/json",
      "href": "http://127.0.0.1:8081/searches/f31d7de8a5ddfa3a80b9a9dd06378db1/tilejson.json"
    }
  ]
}

curl http://127.0.0.1:8081/searches/f31d7de8a5ddfa3a80b9a9dd06378db1/info | jq '.search.metadata'
>> {
  "type": "mosaic",
  "minzoom": 8,
  "maxzoom": 13,
  "assets": [
    "B04",
    "B03",
    "B02"
  ],
  "defaults": {
    "true_color": {
      "assets": [
        "B04",
        "B03",
        "B02"
      ],
      "color_formula": "Gamma RGB 3.5 Saturation 1.7 Sigmoidal RGB 15 0.35"
    }
  }
}

Fetch mosaic `Tiles`¶

When we have an id we can call the dynamic tiler and ask for Map Tiles.

How it works

On each Tile request, the tiler api is going to call the PgSTAC geometrysearch function with the id and the Tile geometry to get the list of STAC Items (code). Then based on the assets parameter, the tiler will construct the tile image (code).

Important

Because Tiles will be created from STAC Items we HAVE TO pass assets={stac asset} option to the tile endpoint to tell the tiler which STAC assets has to be used.

See full list of options

Example

curl 'http://127.0.0.1:8081/searches/f1ed59f0a6ad91ed80ae79b7b52bc707/tiles/8/40/102.png?assets=B01&rescale=0,16000 > 8-40-102.png

STAC Collection - `/collections/{collection_id}`¶

No need for the user to register search queries for those endpoints. The tiler will automatically register a search query (collection={collection_id}).

example

curl http://127.0.0.1:8081/collections/my-collection/tilejson.json?assets=data
{
  "tilejson": "2.2.0",
  "name": "Mosaic for 'my-collection' Collection",
  "version": "1.0.0",
  "scheme": "xyz",
  "tiles": [
    "http://127.0.0.1:8081/collections/my-collection/tiles/WebMercatorQuad/{z}/{x}/{y}?assets=data"
  ],
  "minzoom": 0,
  "maxzoom": 24,
  "bounds": [
    -180,
    -90,
    180,
    90
  ],
  "center": [
    0,
    0,
    0
  ]
}

STAC Item - `/collections/{collection_id}/items/{item_id}`¶

titiler-pgstac can also be used to access individual item stored in the PgSTAC database. By default the titiler-pgstac application will have a set of /collections/{collection_id}/items/{item_id}/... endpoints. The endpoints are created using titiler.core.factory.MultiBaseTilerFactory but using a custom path_dependency with collection_id and item_id path parameters instead of the STAC url as query parameter.

example

curl http://127.0.0.1:8081/collections/world/items/world_20000_5000/info | jq
{
  "asset": {
    "bounds": [
      153.5000000000667,
      -76.83333333336668,
      179.8333333334053,
      6.4999999999833165
    ],
    "minzoom": 3,
    "maxzoom": 6,
    "band_metadata": [
      [
        "b1",
        {}
      ],
      [
        "b2",
        {}
      ],
      [
        "b3",
        {}
      ]
    ],
    "band_descriptions": [
      [
        "b1",
        ""
      ],
      [
        "b2",
        ""
      ],
      [
        "b3",
        ""
      ]
    ],
    "dtype": "uint8",
    "nodata_type": "None",
    "colorinterp": [
      "red",
      "green",
      "blue"
    ],
    "driver": "GTiff",
    "count": 3,
    "width": 1580,
    "height": 5000,
    "overviews": [
      2,
      4,
      8,
      16
    ]
  }
}

See full list of endpoints

Intro

STAC Searches - /searches/{search_id}¶

Register a PgSTAC Search request¶