use simplejson to allow NaN/inf/-inf in JSON response

CHANGES.md

@@ -1,10 +1,15 @@
 # Release Notes
 
-## 0.3.10 (TBD)
+## 0.3.10 (2021-09-23)
+
+### titiler.core
+
+- add custom JSONResponse using [simplejson](https://simplejson.readthedocs.io/en/latest/) to allow NaN/inf/-inf values
 
 ### titiler.application
 
 - switch to `starlette_cramjam` compression middleware (ref: https://github.com/developmentseed/titiler/issues/369)
+- use `titiler.core.resources.responses.JSONResponse` as default application response.
 
 ## 0.3.9 (2021-09-07)
 

src/titiler/application/tests/routes/test_cog.py

@@ -476,3 +476,23 @@ def test_validate_cog(app, url):
     response = app.get(f"/cog/validate?url={os.path.join(DATA_DIR, 'cog.tif')}")
     assert response.status_code == 200
     assert response.json()["COG"]
+
+
+@patch("rio_tiler.io.cogeo.rasterio")
+def test_info_nan(rio, app):
+    """test /info endpoint."""
+    rio.open = mock_rasterio_open
+
+    response = app.get("/cog/info?url=https://myurl.com/cog_with_nan.tif")
+    assert response.status_code == 200
+    body = response.json()
+    assert body["dtype"] == "float32"
+    assert body["nodata_type"] == "Nodata"
+
+    response = app.get("/cog/info.geojson?url=https://myurl.com/cog_with_nan.tif")
+    assert response.status_code == 200
+    assert response.headers["content-type"] == "application/geo+json"
+    body = response.json()
+    assert body["geometry"]
+    assert body["properties"]["nodata_type"] == "Nodata"
+    assert body["properties"]["nodata_value"] is None

src/titiler/application/titiler/application/main.py

@@ -13,6 +13,7 @@
     LowerCaseQueryStringMiddleware,
     TotalTimeMiddleware,
 )
+from titiler.core.resources.responses import JSONResponse
 from titiler.mosaic.errors import MOSAIC_STATUS_CODES
 
 from fastapi import FastAPI
@@ -33,6 +34,7 @@
     description="A lightweight Cloud Optimized GeoTIFF tile server",
     version=titiler_version,
     root_path=api_settings.root_path,
+    default_response_class=JSONResponse,
 )
 
 if not api_settings.disable_cog:

src/titiler/core/setup.py

@@ -14,6 +14,7 @@
     "pydantic",
     "rasterio",
     "rio-tiler>=2.1,<2.2",
+    "simplejson",
     # Additional requirements for python 3.6
     "async_exit_stack>=1.0.1,<2.0.0;python_version<'3.7'",
     "async_generator>=1.10,<2.0.0;python_version<'3.7'",

src/titiler/core/titiler/core/resources/responses.py

@@ -1,14 +1,36 @@
 """Common response models."""
 
-from starlette.responses import JSONResponse, Response
+from typing import Any
 
+import simplejson as json
 
-class XMLResponse(Response):
+from starlette import responses
+
+
+class XMLResponse(responses.Response):
     """XML Response"""
 
     media_type = "application/xml"
 
 
+class JSONResponse(responses.JSONResponse):
+    """Custom JSON Response."""
+
+    def render(self, content: Any) -> bytes:
+        """Render JSON.
+
+        Same defaults as starlette.responses.JSONResponse.render but allow NaN to be replaced by null using simplejson
+        """
+        return json.dumps(
+            content,
+            ensure_ascii=False,
+            allow_nan=False,
+            indent=None,
+            ignore_nan=True,
+            separators=(",", ":"),
+        ).encode("utf-8")
+
+
 class GeoJSONResponse(JSONResponse):
     """GeoJSON Response"""