Allow a default rescale parameter to be set via a dependency (#619)

This lets us define a default rescale value from a separate config
without needing to include it in the query params for every request.

Author: samn

CHANGES.md

@@ -1,5 +1,9 @@
 # Release Notes
 
+## Next
+
+* Allow a default `rescale` parameter to be set via a dependency (author @samn, https://github.com/developmentseed/titiler/pull/619)
+
 ## 0.11.5 (2023-03-22)
 
 * fix `TerrainRGB` (change interval from `1.0` to `0.1`)

src/titiler/core/tests/test_factories.py

@@ -6,7 +6,7 @@
 from dataclasses import dataclass
 from enum import Enum
 from io import BytesIO
-from typing import Dict, Type
+from typing import Dict, Optional, Type
 from unittest.mock import patch
 from urllib.parse import urlencode
 
@@ -21,6 +21,7 @@
 from starlette.requests import Request
 from starlette.testclient import TestClient
 
+from titiler.core.dependencies import RescaleType
 from titiler.core.errors import DEFAULT_STATUS_CODES, add_exception_handlers
 from titiler.core.factory import (
     AlgorithmFactory,
@@ -1513,3 +1514,34 @@ def test_AutoFormat_Colormap():
                     0,
                 ]  # when creating a PNG, GDAL will set masked value to 0
                 assert img[:, 500, 500].tolist() == [255, 0, 0, 255]
+
+
+def test_rescale_dependency():
+    """Ensure that we can set default rescale values via the rescale_dependency"""
+
+    def custom_rescale_params() -> Optional[RescaleType]:
+        return [(0, 100)]
+
+    cog = TilerFactory()
+    cog_custom_range = TilerFactory(rescale_dependency=custom_rescale_params)
+
+    app = FastAPI()
+    app.include_router(cog.router, prefix="/cog")
+    app.include_router(cog_custom_range.router, prefix="/cog_custom")
+
+    with TestClient(app) as client:
+        response = client.get(
+            f"/cog/tiles/8/87/48.npy?url={DATA_DIR}/cog.tif&rescale=0,1000"
+        )
+        assert response.status_code == 200
+        assert response.headers["content-type"] == "application/x-binary"
+        npy_tile = numpy.load(BytesIO(response.content))
+        assert npy_tile.shape == (2, 256, 256)  # mask + data
+
+        response = client.get(
+            f"/cog_custom/tiles/8/87/48.npy?url={DATA_DIR}/cog.tif&rescale=0,1000"
+        )
+        assert response.status_code == 200
+        assert response.headers["content-type"] == "application/x-binary"
+        npy_tile_custom = numpy.load(BytesIO(response.content))
+        assert npy_tile.shape == (2, 256, 256)  # mask + data

src/titiler/core/titiler/core/dependencies.py

@@ -350,14 +350,17 @@ class ImageRenderingParams(DefaultDependency):
     )
 
 
+RescaleType = List[Tuple[float, ...]]
+
+
 def RescalingParams(
     rescale: Optional[List[str]] = Query(
         None,
         title="Min/Max data Rescaling",
         description="comma (',') delimited Min,Max range. Can set multiple time for multiple bands.",
         example=["0,2000", "0,1000", "0,10000"],  # band 1  # band 2  # band 3
     )
-) -> Optional[List[Tuple[float, ...]]]:
+) -> Optional[RescaleType]:
     """Min/Max data Rescaling"""
     if rescale:
         return [tuple(map(float, r.replace(" ", "").split(","))) for r in rescale]

src/titiler/core/titiler/core/factory.py

@@ -41,6 +41,7 @@
     HistogramParams,
     ImageParams,
     ImageRenderingParams,
+    RescaleType,
     RescalingParams,
     StatisticsParams,
 )
@@ -141,6 +142,8 @@ class BaseTilerFactory(metaclass=abc.ABCMeta):
     render_dependency: Type[DefaultDependency] = ImageRenderingParams
     colormap_dependency: Callable[..., Optional[ColorMapType]] = ColorMapParams
 
+    rescale_dependency: Callable[..., Optional[RescaleType]] = RescalingParams
+
     # Post Processing Dependencies (algorithm)
     process_dependency: Callable[
         ..., Optional[BaseAlgorithm]
@@ -512,7 +515,7 @@ def tile(
                 description="Buffer on each side of the given tile. It must be a multiple of `0.5`. Output **tilesize** will be expanded to `tilesize + 2 * buffer` (e.g 0.5 = 257x257, 1.0 = 258x258).",
             ),
             post_process=Depends(self.process_dependency),
-            rescale: Optional[List[Tuple[float, ...]]] = Depends(RescalingParams),
+            rescale=Depends(self.rescale_dependency),
             color_formula: Optional[str] = Query(
                 None,
                 title="Color Formula",
@@ -604,9 +607,7 @@ def tilejson(
                 description="Buffer on each side of the given tile. It must be a multiple of `0.5`. Output **tilesize** will be expanded to `tilesize + 2 * buffer` (e.g 0.5 = 257x257, 1.0 = 258x258).",
             ),
             post_process=Depends(self.process_dependency),  # noqa
-            rescale: Optional[List[Tuple[float, ...]]] = Depends(
-                RescalingParams
-            ),  # noqa
+            rescale=Depends(self.rescale_dependency),  # noqa
             color_formula: Optional[str] = Query(  # noqa
                 None,
                 title="Color Formula",
@@ -687,9 +688,7 @@ def map_viewer(
                 description="Buffer on each side of the given tile. It must be a multiple of `0.5`. Output **tilesize** will be expanded to `tilesize + 2 * buffer` (e.g 0.5 = 257x257, 1.0 = 258x258).",
             ),
             post_process=Depends(self.process_dependency),  # noqa
-            rescale: Optional[List[Tuple[float, ...]]] = Depends(
-                RescalingParams
-            ),  # noqa
+            rescale=Depends(self.rescale_dependency),  # noqa
             color_formula: Optional[str] = Query(  # noqa
                 None,
                 title="Color Formula",
@@ -754,9 +753,7 @@ def wmts(
                 description="Buffer on each side of the given tile. It must be a multiple of `0.5`. Output **tilesize** will be expanded to `tilesize + 2 * buffer` (e.g 0.5 = 257x257, 1.0 = 258x258).",
             ),
             post_process=Depends(self.process_dependency),  # noqa
-            rescale: Optional[List[Tuple[float, ...]]] = Depends(
-                RescalingParams
-            ),  # noqa
+            rescale=Depends(self.rescale_dependency),  # noqa
             color_formula: Optional[str] = Query(  # noqa
                 None,
                 title="Color Formula",
@@ -886,7 +883,7 @@ def preview(
             dataset_params=Depends(self.dataset_dependency),
             img_params=Depends(self.img_dependency),
             post_process=Depends(self.process_dependency),
-            rescale: Optional[List[Tuple[float, ...]]] = Depends(RescalingParams),
+            rescale=Depends(self.rescale_dependency),  # noqa
             color_formula: Optional[str] = Query(
                 None,
                 title="Color Formula",
@@ -956,7 +953,7 @@ def part(
             dataset_params=Depends(self.dataset_dependency),
             image_params=Depends(self.img_dependency),
             post_process=Depends(self.process_dependency),
-            rescale: Optional[List[Tuple[float, ...]]] = Depends(RescalingParams),
+            rescale=Depends(self.rescale_dependency),
             color_formula: Optional[str] = Query(
                 None,
                 title="Color Formula",
@@ -1021,7 +1018,7 @@ def geojson_crop(
             dataset_params=Depends(self.dataset_dependency),
             image_params=Depends(self.img_dependency),
             post_process=Depends(self.process_dependency),
-            rescale: Optional[List[Tuple[float, ...]]] = Depends(RescalingParams),
+            rescale=Depends(self.rescale_dependency),
             color_formula: Optional[str] = Query(
                 None,
                 title="Color Formula",

src/titiler/mosaic/titiler/mosaic/factory.py

@@ -21,7 +21,7 @@
 from starlette.requests import Request
 from starlette.responses import HTMLResponse, Response
 
-from titiler.core.dependencies import DefaultDependency, RescalingParams
+from titiler.core.dependencies import DefaultDependency
 from titiler.core.factory import BaseTilerFactory, img_endpoint_params, templates
 from titiler.core.models.mapbox import TileJSON
 from titiler.core.resources.enums import ImageType, MediaType, OptionalHeader
@@ -254,7 +254,7 @@ def tile(
                 description="Buffer on each side of the given tile. It must be a multiple of `0.5`. Output **tilesize** will be expanded to `tilesize + 2 * tile_buffer` (e.g 0.5 = 257x257, 1.0 = 258x258).",
             ),
             post_process=Depends(self.process_dependency),
-            rescale: Optional[List[Tuple[float, ...]]] = Depends(RescalingParams),
+            rescale=Depends(self.rescale_dependency),
             color_formula: Optional[str] = Query(
                 None,
                 title="Color Formula",
@@ -371,9 +371,7 @@ def tilejson(
                 description="Buffer on each side of the given tile. It must be a multiple of `0.5`. Output **tilesize** will be expanded to `tilesize + 2 * tile_buffer` (e.g 0.5 = 257x257, 1.0 = 258x258).",
             ),
             post_process=Depends(self.process_dependency),  # noqa
-            rescale: Optional[List[Tuple[float, ...]]] = Depends(
-                RescalingParams
-            ),  # noqa
+            rescale=Depends(self.rescale_dependency),  # noqa
             color_formula: Optional[str] = Query(  # noqa
                 None,
                 title="Color Formula",
@@ -463,9 +461,7 @@ def map_viewer(
                 title="Tile buffer.",
                 description="Buffer on each side of the given tile. It must be a multiple of `0.5`. Output **tilesize** will be expanded to `tilesize + 2 * tile_buffer` (e.g 0.5 = 257x257, 1.0 = 258x258).",
             ),
-            rescale: Optional[List[Tuple[float, ...]]] = Depends(
-                RescalingParams
-            ),  # noqa
+            rescale=Depends(self.rescale_dependency),  # noqa
             color_formula: Optional[str] = Query(  # noqa
                 None,
                 title="Color Formula",
@@ -532,9 +528,7 @@ def wmts(
                 description="Buffer on each side of the given tile. It must be a multiple of `0.5`. Output **tilesize** will be expanded to `tilesize + 2 * tile_buffer` (e.g 0.5 = 257x257, 1.0 = 258x258).",
             ),
             post_process=Depends(self.process_dependency),  # noqa
-            rescale: Optional[List[Tuple[float, ...]]] = Depends(
-                RescalingParams
-            ),  # noqa
+            rescale=Depends(self.rescale_dependency),  # noqa
             color_formula: Optional[str] = Query(  # noqa
                 None,
                 title="Color Formula",