Validate event search parameters in FastAPI query models

server/polar/event/endpoints.py

@@ -4,7 +4,7 @@
 
 from fastapi import Depends, Query
 from fastapi.exceptions import RequestValidationError
-from pydantic import UUID4, ValidationError
+from pydantic import UUID4
 
 from polar.exceptions import (
     NotPermitted,
@@ -19,7 +19,6 @@
 )
 from polar.kit.time_queries import is_under_limits
 from polar.kit.versioning import version
-from polar.meter.filter import Filter
 from polar.models import Event
 from polar.openapi import APITag
 from polar.postgres import (
@@ -61,16 +60,6 @@
 router = APIRouter(prefix="/events", tags=["events", APITag.public])
 
 
-def _parse_filter(filter: str | None) -> Filter | None:
-    # FastAPI does not support complex schemas in query parameters.
-    if filter is None:
-        return None
-    try:
-        return Filter.model_validate_json(filter)
-    except ValidationError as e:
-        raise RequestValidationError(e.errors()) from e
-
-
 def _validate_query(query: str | None, organization_id: Sequence[UUID4] | None) -> None:
     if query is None:
         return
@@ -135,13 +124,12 @@ async def list(
 ) -> ListResource[EventSchema] | ListResourceWithCursorPagination[EventSchema]:
     """List events."""
 
-    parsed_filter = _parse_filter(filters.filter)
     _validate_query(filters.query, filters.organization_id)
 
     result = await event_service.list(
         session,
         auth_subject,
-        filter=parsed_filter,
+        filter=filters.filter,
         start_timestamp=filters.start_timestamp,
         end_timestamp=filters.end_timestamp,
         organization_id=filters.organization_id,
@@ -195,13 +183,12 @@ async def get_statistics_by_type(
     Accepts the same filters as the event list, except the event name, so every
     event type gets a count under the other filters.
     """
-    parsed_filter = _parse_filter(filters.filter)
     _validate_query(filters.query, filters.organization_id)
 
     items = await event_service.list_event_type_stats(
         session,
         auth_subject,
-        filter=parsed_filter,
+        filter=filters.filter,
         start_timestamp=filters.start_timestamp,
         end_timestamp=filters.end_timestamp,
         organization_id=filters.organization_id,
@@ -244,15 +231,14 @@ async def get_histogram(
                 }
             ]
         )
-    parsed_filter = _parse_filter(filters.filter)
     _validate_query(filters.query, filters.organization_id)
 
     return await event_service.get_histogram(
         session,
         auth_subject,
         start_timestamp=filters.start_timestamp,
         end_timestamp=filters.end_timestamp,
-        filter=parsed_filter,
+        filter=filters.filter,
         organization_id=filters.organization_id,
         customer_id=filters.customer_id,
         external_customer_id=filters.external_customer_id,
@@ -394,7 +380,6 @@ async def list_statistics_timeseries(
             ]
         )
 
-    parsed_filter = _parse_filter(filters.filter)
     _validate_query(filters.query, filters.organization_id)
 
     return await event_service.list_statistics_timeseries(
@@ -404,7 +389,7 @@ async def list_statistics_timeseries(
         end_date=filters.end_date,
         timezone=ZoneInfo(filters.timezone),
         interval=filters.interval,
-        filter=parsed_filter,
+        filter=filters.filter,
         organization_id=filters.organization_id,
         customer_id=filters.customer_id,
         external_customer_id=filters.external_customer_id,

server/polar/event/schemas.py

@@ -13,6 +13,8 @@
     AwareDatetime,
     Discriminator,
     Field,
+    Json,
+    WithJsonSchema,
 )
 from pydantic.type_adapter import TypeAdapter
 from pydantic_extra_types.timezone_name import TimeZoneName
@@ -70,6 +72,7 @@
 )
 from polar.kit.time_queries import TimeInterval
 from polar.kit.versioning import QuerySchema
+from polar.meter.filter import Filter
 from polar.meter.schemas import MeterID
 from polar.models.event import EventSource
 from polar.organization.schemas import OrganizationID
@@ -918,8 +921,12 @@ def _validate_aggregate_field(value: str) -> bool:
 ]
 
 
+# Keep the JSON-encoded query parameter a string in generated clients.
+EventQueryFilter = Annotated[Json[Filter], WithJsonSchema({"type": "string"})]
+
+
 class EventListParams(QuerySchema):
-    filter: str | None = Field(
+    filter: EventQueryFilter | None = Field(
         None,
         description=(
             "Filter events following filter clauses. "
@@ -968,7 +975,7 @@ class EventListParams(QuerySchema):
 
 
 class EventTypeStatisticsParams(QuerySchema):
-    filter: str | None = Field(
+    filter: EventQueryFilter | None = Field(
         None,
         description=(
             "Filter events following filter clauses. "
@@ -1081,7 +1088,7 @@ class EventListStatisticsTimeseriesParams(QuerySchema):
         description="Timezone to use for the dates. Default is UTC.",
     )
     interval: TimeInterval = Field(..., description="Interval between two dates.")
-    filter: str | None = Field(
+    filter: EventQueryFilter | None = Field(
         None,
         description=(
             "Filter events following filter clauses. "