fix: add/raise appropriate error for /cql endpoint where no filter is provided

prez/app.py

@@ -29,7 +29,7 @@
     NoEndpointNodeshapeException,
     NoProfilesException,
     PrefixNotFoundException,
-    URINotFoundException,
+    URINotFoundException, MissingFilterQueryError,
 )
 from prez.middleware import create_validate_header_middleware
 from prez.repositories import OxrdflibRepo, PyoxigraphRepo, RemoteSparqlRepo
@@ -59,7 +59,7 @@
     catch_no_endpoint_nodeshape_exception,
     catch_no_profiles_exception,
     catch_prefix_not_found_exception,
-    catch_uri_not_found_exception,
+    catch_uri_not_found_exception, catch_missing_filter_query_param,
 )
 from prez.services.generate_profiles import create_profiles_graph
 from prez.services.prez_logging import setup_logger
@@ -181,6 +181,7 @@ def assemble_app(
             NoProfilesException: catch_no_profiles_exception,
             InvalidSPARQLQueryException: catch_invalid_sparql_query,
             NoEndpointNodeshapeException: catch_no_endpoint_nodeshape_exception,
+            MissingFilterQueryError: catch_missing_filter_query_param
         },
         **kwargs
     )

prez/dependencies.py

@@ -28,7 +28,7 @@
 )
 from prez.exceptions.model_exceptions import (
     NoEndpointNodeshapeException,
-    URINotFoundException,
+    URINotFoundException, MissingFilterQueryError,
 )
 from prez.enums import SearchMethod
 from prez.models.query_params import QueryParams
@@ -147,6 +147,29 @@ async def load_annotations_data_to_oxigraph(store: Store):
     store.load(file_bytes, "application/n-triples")
 
 
+
+async def get_endpoint_uri_type(
+    request: Request,
+    system_repo: Repo = Depends(get_system_repo),
+) -> tuple[URIRef, URIRef]:
+    """
+    Returns the URI of the endpoint and its type (ObjectEndpoint or ListingEndpoint)
+    """
+    endpoint_uri = URIRef(request.scope.get("route").name)
+    ep_type_fs = await get_classes_single(endpoint_uri, system_repo)
+    ep_types = list(ep_type_fs)
+
+    # Iterate over each item in ep_types
+    for ep_type in ep_types:
+        # Check if the current ep_type is either ObjectEndpoint or ListingEndpoint
+        if ep_type in [ONT.ObjectEndpoint, ONT.ListingEndpoint]:
+            return endpoint_uri, ep_type
+    raise ValueError(
+        "Endpoint must be declared as either a 'https://prez.dev/ont/ObjectEndpoint' or a "
+        "'https://prez.dev/ont/ListingEndpoint' in order for the appropriate profile to be determined."
+    )
+
+
 async def cql_post_parser_dependency(
     request: Request,
     queryable_props: list = Depends(get_queryable_props),
@@ -168,6 +191,7 @@ async def cql_post_parser_dependency(
 async def cql_get_parser_dependency(
     query_params: QueryParams = Depends(),
     queryable_props: list = Depends(get_queryable_props),
+    endpoint_uri_type: str = Depends(get_endpoint_uri_type),
 ) -> CQLParser:
     if query_params._filter:
         try:
@@ -186,6 +210,9 @@ async def cql_get_parser_dependency(
             raise HTTPException(
                 status_code=400, detail="Invalid CQL format: Parsing failed."
             )
+    elif endpoint_uri_type[0] == URIRef('https://prez.dev/endpoint/extended-ogc-records/cql-get'):
+        raise MissingFilterQueryError("filter query parameter with a valid CQL JSON expression must be provided when "
+                                      "using the /cql endpoint.")
 
 
 async def get_jena_fts_shacl_predicates(system_repo: Repo):
@@ -268,28 +295,6 @@ async def generate_search_query(
         return search_query
 
 
-async def get_endpoint_uri_type(
-    request: Request,
-    system_repo: Repo = Depends(get_system_repo),
-) -> tuple[URIRef, URIRef]:
-    """
-    Returns the URI of the endpoint and its type (ObjectEndpoint or ListingEndpoint)
-    """
-    endpoint_uri = URIRef(request.scope.get("route").name)
-    ep_type_fs = await get_classes_single(endpoint_uri, system_repo)
-    ep_types = list(ep_type_fs)
-
-    # Iterate over each item in ep_types
-    for ep_type in ep_types:
-        # Check if the current ep_type is either ObjectEndpoint or ListingEndpoint
-        if ep_type in [ONT.ObjectEndpoint, ONT.ListingEndpoint]:
-            return endpoint_uri, ep_type
-    raise ValueError(
-        "Endpoint must be declared as either a 'https://prez.dev/ont/ObjectEndpoint' or a "
-        "'https://prez.dev/ont/ListingEndpoint' in order for the appropriate profile to be determined."
-    )
-
-
 async def generate_concept_hierarchy_query(
     request: Request,
     endpoint_uri_type: tuple[URIRef, URIRef] = Depends(get_endpoint_uri_type),

prez/exceptions/model_exceptions.py

@@ -75,3 +75,12 @@ def __init__(self, ep_uri: str, hierarchy_level: int):
             f"{hierarchy_level}, and parent URI"
         )
         super().__init__(self.message)
+
+
+class MissingFilterQueryError(ValueError):
+    """
+    Raised when a filter query is missing.
+    """
+    def __init__(self, message):
+        self.message = message
+        super().__init__(self.message)

prez/routers/ogc_features_router.py

@@ -26,7 +26,7 @@
     NoEndpointNodeshapeException,
     NoProfilesException,
     PrefixNotFoundException,
-    URINotFoundException,
+    URINotFoundException, MissingFilterQueryError,
 )
 from prez.models.ogc_features import OGCFeaturesLandingPage, generate_landing_page_links
 from prez.models.query_params import QueryParams
@@ -44,7 +44,7 @@
     catch_no_endpoint_nodeshape_exception,
     catch_no_profiles_exception,
     catch_prefix_not_found_exception,
-    catch_uri_not_found_exception,
+    catch_uri_not_found_exception, catch_missing_filter_query_param,
 )
 from prez.services.listings import ogc_features_listing_function
 from prez.services.objects import ogc_features_object_function

prez/services/exception_catchers.py

@@ -8,7 +8,7 @@
     NoEndpointNodeshapeException,
     NoProfilesException,
     PrefixNotFoundException,
-    URINotFoundException,
+    URINotFoundException, MissingFilterQueryError,
 )
 
 
@@ -90,3 +90,14 @@ async def catch_no_endpoint_nodeshape_exception(
             "detail": exc.message,
         },
     )
+
+async def catch_missing_filter_query_param(
+    request: Request, exc: MissingFilterQueryError
+):
+    return JSONResponse(
+        status_code=400,
+        content={
+            "error": "Bad Request",
+            "detail": exc.message,
+        },
+    )