better logs

backend/src/optimization/optimizer.py

@@ -597,7 +597,7 @@ class Optimizer:
 
         # Raise error if no solution is found. FIXME: for now this throws the internal server error
         if status != 'Optimal' :
-            self.logger.error("The problem is overconstrained, no solution on first try.")
+            self.logger.warning("The problem is overconstrained, no solution on first try.")
             raise ArithmeticError("No solution could be found. Please try again with more time or different preferences.")
 
         # If there is a solution, we're good to go, just check for connectiveness
@@ -607,7 +607,7 @@ class Optimizer:
         while circles is not None :
             i += 1
             if i == self.max_iter :
-                self.logger.error(f'Timeout: No solution found after {self.max_iter} iterations.')
+                self.logger.warning(f'Timeout: No solution found after {self.max_iter} iterations.')
                 raise TimeoutError(f"Optimization took too long. No solution found after {self.max_iter} iterations.")
 
             for circle in circles :
@@ -617,12 +617,13 @@ class Optimizer:
             try :
                 prob.solve(pl.PULP_CBC_CMD(msg=False, timeLimit=self.time_limit, gapRel=self.gap_rel))
             except Exception as exc :
+                self.logger.warning("No solution found: {str(exc)")
                 raise Exception(f"No solution found: {str(exc)}") from exc
 
             solution = [pl.value(var) for var in x]
 
             if pl.LpStatus[prob.status] != 'Optimal' :
-                self.logger.error("The problem is overconstrained, no solution after {i} cycles.")
+                self.logger.warning("The problem is overconstrained, no solution after {i} cycles.")
                 raise ArithmeticError("No solution could be found. Please try again with more time or different preferences.")
 
             circles = self.is_connected(solution)