feat: added min and max value to algorithms (#783)

* feat: added min and max value to algorithms

* feat: add title and description to algorithm metadata

* lint

* update changelog

---------

Co-authored-by: vincentsarago <[email protected]>

Author: JinIgarashi

CHANGES.md

@@ -5,6 +5,7 @@
 ### titiler.core
 
 * Add `use_epsg` parameter to WMTS endpoint to resolve ArcMAP issues and fix XML formating (author @gadomski, https://github.com/developmentseed/titiler/pull/782)
+* Add more OpenAPI metadata for algorithm (author @JinIgarashi, https://github.com/developmentseed/titiler/pull/783)
 
 ### titiler.application
 

src/titiler/core/titiler/core/algorithm/base.py

@@ -32,6 +32,9 @@ def __call__(self, img: ImageData) -> ImageData:
 class AlgorithmMetadata(BaseModel):
     """Algorithm metadata."""
 
+    title: Optional[str] = None
+    description: Optional[str] = None
+
     inputs: Dict
     outputs: Dict
     parameters: Dict

src/titiler/core/titiler/core/algorithm/dem.py

@@ -1,6 +1,7 @@
 """titiler.core.algorithm DEM."""
 
 import numpy
+from pydantic import Field
 from rasterio import windows
 from rio_tiler.colormap import apply_cmap, cmap
 from rio_tiler.models import ImageData
@@ -12,10 +13,13 @@
 class HillShade(BaseAlgorithm):
     """Hillshade."""
 
+    title: str = "Hillshade"
+    description: str = "Create hillshade from DEM dataset."
+
     # parameters
-    azimuth: int = 90
-    angle_altitude: float = 90.0
-    buffer: int = 3
+    azimuth: int = Field(90, ge=0, lt=360)
+    angle_altitude: float = Field(90.0, ge=-90.0, lt=90.0)
+    buffer: int = Field(3, ge=0, lt=99)
 
     # metadata
     input_nbands: int = 1
@@ -61,11 +65,14 @@ class Contours(BaseAlgorithm):
     Original idea from https://custom-scripts.sentinel-hub.com/dem/contour-lines/
     """
 
+    title: str = "Contours"
+    description: str = "Create contours from DEM dataset."
+
     # parameters
-    increment: int = 35
-    thickness: int = 1
-    minz: int = -12000
-    maxz: int = 8000
+    increment: int = Field(35, ge=0, lt=999)
+    thickness: int = Field(1, ge=0, lt=10)
+    minz: int = Field(-12000, ge=-99999, lt=99999)
+    maxz: int = Field(8000, ge=-99999, lt=99999)
 
     # metadata
     input_nbands: int = 1
@@ -99,6 +106,9 @@ def __call__(self, img: ImageData) -> ImageData:
 class Terrarium(BaseAlgorithm):
     """Encode DEM into RGB (Mapzen Terrarium)."""
 
+    title: str = "Terrarium"
+    description: str = "Encode DEM into RGB (Mapzen Terrarium)."
+
     # metadata
     input_nbands: int = 1
     output_nbands: int = 3
@@ -122,9 +132,12 @@ def __call__(self, img: ImageData) -> ImageData:
 class TerrainRGB(BaseAlgorithm):
     """Encode DEM into RGB (Mapbox Terrain RGB)."""
 
+    title: str = "Terrarium"
+    description: str = "Encode DEM into RGB (Mapbox Terrain RGB)."
+
     # parameters
-    interval: float = 0.1
-    baseval: float = -10000.0
+    interval: float = Field(0.1, ge=0.0, lt=1.0)
+    baseval: float = Field(-10000.0, ge=-99999.0, lt=99999.0)
 
     # metadata
     input_nbands: int = 1

src/titiler/core/titiler/core/algorithm/index.py

@@ -11,6 +11,9 @@
 class NormalizedIndex(BaseAlgorithm):
     """Normalized Difference Index."""
 
+    title: str = "Normalized Difference Index"
+    description: str = "Compute normalized difference index from two bands."
+
     # metadata
     input_nbands: int = 2
     output_nbands: int = 1

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

@@ -1667,6 +1667,15 @@ def metadata(algorithm: BaseAlgorithm) -> AlgorithmMetadata:
             """Algorithm Metadata"""
             props = algorithm.model_json_schema()["properties"]
 
+            # title and description
+            info = {
+                k: v["default"]
+                for k, v in props.items()
+                if k == "title" or k == "description"
+            }
+            title = info.get("title", None)
+            description = info.get("description", None)
+
             # Inputs Metadata
             ins = {
                 k.replace("input_", ""): v["default"]
@@ -1685,9 +1694,18 @@ def metadata(algorithm: BaseAlgorithm) -> AlgorithmMetadata:
             params = {
                 k: v
                 for k, v in props.items()
-                if not k.startswith("input_") and not k.startswith("output_")
+                if not k.startswith("input_")
+                and not k.startswith("output_")
+                and k != "title"
+                and k != "description"
             }
-            return AlgorithmMetadata(inputs=ins, outputs=outs, parameters=params)
+            return AlgorithmMetadata(
+                title=title,
+                description=description,
+                inputs=ins,
+                outputs=outs,
+                parameters=params,
+            )
 
         @self.router.get(
             "/algorithms",