F4KRP-125 Get polyline from stops

backend/python/app/models/route.py

@@ -23,6 +23,7 @@ class RouteBase(SQLModel):
         default=None, sa_column=Column(DateTime(timezone=True), nullable=True)
     )
     expires_at: datetime | None = Field(default=None)
+    ends_at_warehouse: bool = Field(default=False)
 
 
 class Route(RouteBase, BaseModel, table=True):
@@ -69,6 +70,7 @@ class RouteUpdate(SQLModel):
     encoded_polyline: str | None = None
     polyline_updated_at: datetime | None = None
     expires_at: datetime | None = None
+    ends_at_warehouse: bool | None = None
 
 
 class RouteWithDateRead(SQLModel):

backend/python/app/utilities/routes_utils.py

@@ -0,0 +1,111 @@
+from typing import TYPE_CHECKING
+
+from fastapi import HTTPException
+from google.api_core import exceptions as google_exceptions
+from google.api_core.client_options import ClientOptions
+from google.maps import routing_v2
+
+from app.config import settings
+
+if TYPE_CHECKING:
+    from app.models.location import Location
+
+
+async def fetch_route_polyline(
+    locations: list["Location"],
+    warehouse_lat: float,
+    warehouse_lon: float,
+    ends_at_warehouse: bool,
+) -> tuple[str, float]:
+    """Fetch encoded polyline from Google Maps Routes API.
+
+    Args:
+        locations: Ordered list of Location objects (route stops)
+        warehouse_lat: Warehouse latitude
+        warehouse_lon: Warehouse longitude
+        ends_at_warehouse: If True, route returns to warehouse
+
+    Returns:
+        Tuple with encoded polyline string and total distance in kilometers
+
+    Raises:
+        HTTPException: If API request fails
+        ValueError: If locations list is empty or API key not configured
+    """
+    if not locations:
+        raise ValueError("Locations list cannot be empty")
+
+    if not settings.google_maps_api_key:
+        raise ValueError("Google Maps API key is not configured in settings")
+
+    # Build waypoints
+    origin = routing_v2.Waypoint(
+        location=routing_v2.Location(
+            lat_lng={"latitude": warehouse_lat, "longitude": warehouse_lon}
+        )
+    )
+
+    intermediates = [
+        routing_v2.Waypoint(
+            location=routing_v2.Location(
+                lat_lng={"latitude": loc.latitude, "longitude": loc.longitude}
+            )
+        )
+        for loc in locations
+    ]
+
+    if ends_at_warehouse:
+        destination = origin
+        waypoints_to_use = intermediates
+    else:
+        if len(intermediates) > 1:
+            waypoints_to_use = intermediates[:-1]
+            destination = intermediates[-1]
+        else:
+            waypoints_to_use = None
+            destination = intermediates[0]
+
+    # Build request
+    request = routing_v2.ComputeRoutesRequest(
+        origin=origin,
+        destination=destination,
+        intermediates=waypoints_to_use,
+        travel_mode=routing_v2.RouteTravelMode.DRIVE,
+        routing_preference=routing_v2.RoutingPreference.TRAFFIC_AWARE,
+    )
+
+    try:
+        # Create client with API key
+        options = ClientOptions(api_key=settings.google_maps_api_key)
+        client = routing_v2.RoutesAsyncClient(client_options=options)
+
+        response = await client.compute_routes(
+            request=request,
+            metadata=[
+                (
+                    "x-goog-fieldmask",
+                    "routes.polyline.encodedPolyline,routes.distanceMeters",
+                )
+            ],
+        )
+
+        if not response.routes:
+            raise HTTPException(
+                status_code=500,
+                detail="Google Maps API returned no routes",
+            )
+
+        route = response.routes[0]
+        polyline = route.polyline.encoded_polyline
+        distance_km = route.distance_meters / 1000.0
+
+        return polyline, distance_km
+
+    except google_exceptions.GoogleAPICallError as e:
+        raise HTTPException(
+            status_code=503, detail=f"Google Maps API error: {e!s}"
+        ) from e
+    except google_exceptions.RetryError as e:
+        raise HTTPException(status_code=504, detail="Request timed out") from e
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=f"Unexpected error: {e!s}") from e

backend/python/migrations/versions/eb010a6ed5ad_added_ends_at_warehouse_to_route_model.py

@@ -0,0 +1,28 @@
+"""added ends_at_warehouse to route model
+
+Revision ID: eb010a6ed5ad
+Revises: ba76119b3e4c
+Create Date: 2025-12-01 00:31:47.827096
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = 'eb010a6ed5ad'
+down_revision = 'ba76119b3e4c'
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.add_column('routes', sa.Column('ends_at_warehouse', sa.Boolean(), nullable=False, server_default='false'))
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_column('routes', 'ends_at_warehouse')
+    # ### end Alembic commands ###

backend/python/requirements.txt

@@ -22,6 +22,7 @@ google-api-core>=2.0.0
 google-cloud-core>=1.6.0
 google-cloud-firestore>=2.1.0
 google-cloud-storage>=1.37.1
+google-maps-routing>=0.1.0
 googleapis-common-protos>=1.70.0
 firebase-admin>=6.0.0