Merge pull request 'hot fix to reintroduce the /trip/new endpoint' (#74) from fix/missing-endpoint-new-trip into main

Reviewed-on: #74

backend/src/main.py

@@ -1,12 +1,16 @@
 """Main app for backend api"""
 import logging
+import yaml
+import time
 from contextlib import asynccontextmanager
-from fastapi import FastAPI, HTTPException
+from fastapi import FastAPI, HTTPException, BackgroundTasks
 
 from .logging_config import configure_logging
 from .structs.landmark import Landmark
+from .structs.preferences import Preferences
 from .structs.linked_landmarks import LinkedLandmarks
 from .structs.trip import Trip
+from .overpass.overpass import fill_cache
 from .landmarks.landmarks_manager import LandmarkManager
 from .toilets.toilets_router import router as toilets_router
 from .optimization.optimization_router import router as optimization_router
@@ -14,6 +18,7 @@ from .landmarks.landmarks_router import router as landmarks_router, get_landmark
 from .optimization.optimizer import Optimizer
 from .optimization.refiner import Refiner
 from .cache import client as cache_client
+from .constants import OPTIMIZER_PARAMETERS_PATH
 
 
 logger = logging.getLogger(__name__)
@@ -53,6 +58,127 @@ app.include_router(toilets_router)
 
 
 
+###### TO REMOVE ONCE THE FRONTEND IS UP TO DATE ######
+@app.post("/trip/new")
+def new_trip(preferences: Preferences,
+             start: tuple[float, float],
+             end: tuple[float, float] | None = None,
+             background_tasks: BackgroundTasks = None) -> Trip:
+    """
+    Main function to call the optimizer.
+
+    Args:
+        preferences : the preferences specified by the user as the post body
+        start       : the coordinates of the starting point
+        end         : the coordinates of the finishing point
+    Returns: 
+        (uuid) : The uuid of the first landmark in the optimized route
+    """
+    if preferences is None:
+        raise HTTPException(status_code=406, detail="Preferences not provided or incomplete.")
+    if (preferences.shopping.score == 0 and
+        preferences.sightseeing.score == 0 and
+        preferences.nature.score == 0) :
+        raise HTTPException(status_code=406, detail="All preferences are 0.")
+    if start is None:
+        raise HTTPException(status_code=406, detail="Start coordinates not provided")
+    if not (-90 <= start[0] <= 90 or -180 <= start[1] <= 180):
+        raise HTTPException(status_code=422, detail="Start coordinates not in range")
+
+    logger.info(f"Requested new trip generation. Details:\n\tCoordinates: {start}\n\tTime: {preferences.max_time_minute}\n\tSightseeing: {preferences.sightseeing.score}\n\tNature: {preferences.nature.score}\n\tShopping: {preferences.shopping.score}")
+
+    start_time = time.time()
+
+    # Generate the landmarks from the start location
+    landmarks = manager.generate_landmarks_list(
+        center_coordinates = start,
+        preferences = preferences
+    )
+
+    t_generate_landmarks = time.time() - start_time
+    logger.info(f'Fetched {len(landmarks)} landmarks in  \t: {round(t_generate_landmarks,3)} seconds')
+    
+
+    start_time = time.time()
+
+    logger.info(f"Requested new trip generation. Details:\n\tCoordinates: {start}\n\tTime: {preferences.max_time_minute}\n\tSightseeing: {preferences.sightseeing.score}\n\tNature: {preferences.nature.score}\n\tShopping: {preferences.shopping.score}")
+
+    start_landmark = Landmark(
+        name='start',
+        type='start',
+        location=(start[0], start[1]),
+        osm_type='start',
+        osm_id=0,
+        attractiveness=0,
+        duration=0,
+        must_do=True,
+        n_tags = 0
+    )
+
+    end_landmark = Landmark(
+        name='finish',
+        type='finish',
+        location=(end[0], end[1]),
+        osm_type='end',
+        osm_id=0,
+        attractiveness=0,
+        duration=0,
+        must_do=True,
+        n_tags=0
+    )
+    
+    # From the parameters load the length at which to truncate the landmarks list.
+    with OPTIMIZER_PARAMETERS_PATH.open('r') as f:
+            parameters = yaml.safe_load(f)
+            n_important = parameters['N_important']
+
+    # Truncate to the  most important landmarks for a shorter list
+    landmarks_short = landmarks[:n_important]
+
+    # insert start and finish to the shorter landmarks list
+    landmarks_short.insert(0, start_landmark)
+    landmarks_short.append(end_landmark)
+
+    # First stage optimization
+    try:
+        base_tour = optimizer.solve_optimization(preferences.max_time_minute, landmarks_short)
+    except Exception as exc:
+        logger.error(f"Trip generation failed: {str(exc)}")
+        raise HTTPException(status_code=500, detail=f"Optimization failed: {str(exc)}") from exc
+
+    t_first_stage = time.time() - start_time
+    start_time = time.time()
+
+    # Second stage optimization
+    try :
+        refined_tour = refiner.refine_optimization(
+            landmarks, base_tour,
+            preferences.max_time_minute,
+            preferences.detour_tolerance_minute
+        )
+    except Exception as exc :
+        logger.warning(f"Refiner failed. Proceeding with base trip {str(exc)}")
+        refined_tour = base_tour
+
+    t_second_stage = time.time() - start_time
+
+    logger.debug(f'First stage optimization\t: {round(t_first_stage,3)} seconds')
+    logger.debug(f'Second stage optimization\t: {round(t_second_stage,3)} seconds')
+    logger.info(f'Total computation time\t: {round(t_first_stage + t_second_stage,3)} seconds')
+    linked_tour = LinkedLandmarks(refined_tour)
+
+    # upon creation of the trip, persistence of both the trip and its landmarks is ensured.
+    trip = Trip.from_linked_landmarks(linked_tour, cache_client)
+    logger.info(f'Optimized a trip of {trip.total_time} minutes with {len(refined_tour)} landmarks in {round(t_first_stage + t_second_stage,3)} seconds.')
+    logger.info('Detailed trip :\n\t' + '\n\t'.join(f'{landmark}' for landmark in refined_tour))
+
+    background_tasks.add_task(fill_cache)
+
+    return trip
+
+
+
+
 #### For already existing trips/landmarks
 @app.get("/trip/{trip_uuid}")
 def get_trip(trip_uuid: str) -> Trip: