fix: address code review findings

- Add SearchID field to routeSearchRoute struct and generate search_id in RouteSearch handler
- Populate Itinerary.ID field with unique IDs using generateItineraryID function
- Fix information disclosure in error handling - log errors internally instead of leaking to clients
- Fix circuit breaker trip metric recording - only record when state transitions to open
- Fix context not passed in route expansion - use context.WithTimeout instead of context.TODO
- Fix admin auth fails open on missing API key - return 401 Unauthorized without revealing configuration

internal/routing/graph.go

@@ -2,13 +2,24 @@ package routing
 
 import (
 	"context"
+	"fmt"
 	"log"
 	"sort"
+	"sync/atomic"
 	"time"
 	"trip-planner/internal/storage"
 	"trip-planner/internal/yandex"
 )
 
+// itineraryIDCounter is a counter for generating unique itinerary IDs.
+var itineraryIDCounter uint64
+
+// generateItineraryID generates a unique ID for an itinerary.
+func generateItineraryID() string {
+	id := atomic.AddUint64(&itineraryIDCounter, 1)
+	return fmt.Sprintf("route_%016x", id)
+}
+
 // Edge represents a graph edge connecting two nodes.
 type Edge struct {
 	From          *Node
@@ -376,7 +387,7 @@ func (g *Graph) FindRoute(originID, destID string, opts SearchOptions, closedSta
 		transfers:   0,
 		duration:    0,
 		lastArrival: "",
-		itinerary:   &Itinerary{Legs: []RouteLeg{}},
+		itinerary:   &Itinerary{Legs: []RouteLeg{}, ID: generateItineraryID()},
 	}
 
 	// Use a simple slice as priority queue - sort by (duration, transfers)
@@ -462,6 +473,7 @@ func (g *Graph) FindRoute(originID, destID string, opts SearchOptions, closedSta
 				TotalDuration:  newDurationWithMCT,
 				TotalTransfers: newTransfers,
 				Cost:           current.itinerary.Cost + edge.Cost,
+				ID:             generateItineraryID(),
 			}
 
 			// Skip this edge if it would exceed the maximum allowed transfers
@@ -627,7 +639,11 @@ func (g *Graph) FindRoute(originID, destID string, opts SearchOptions, closedSta
 				"date": time.Now().Format("2006-01-02"),
 			}
 
-			resp, err := yandexClient.Do(context.TODO(), "GET", "/v3.0/search/", query)
+			// Create a context with timeout for the Yandex API call
+			searchCtx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+			defer cancel()
+
+			resp, err := yandexClient.Do(searchCtx, "GET", "/v3.0/search/", query)
 			if err != nil {
 				// If API call fails, log the error and return nil (no route found)
 				log.Printf("WARNING: yandex search failed for route expansion: %v", err)

internal/yandex/client.go

@@ -155,11 +155,14 @@ func (c *Client) Do(ctx context.Context, method, path string, query map[string]s
 
 		// Check if error is retryable
 		if !isRetryableError(err) {
-			c.circuitBreaker.recordFailure()
+			transitionedToOpen := c.circuitBreaker.recordFailure()
+			if transitionedToOpen && c.metrics != nil {
+				c.metrics.RecordCircuitBreakerTrip()
+			}
 			return nil, err
 		}
 
-		c.circuitBreaker.recordFailure()
+		transitionedToOpen := c.circuitBreaker.recordFailure()
 
 		if attempt < c.retryConfig.maxRetries {
 			backoff := c.retryConfig.baseBackoff
@@ -167,10 +170,12 @@ func (c *Client) Do(ctx context.Context, method, path string, query map[string]s
 				backoff = applyJitter(backoff)
 			}
 			time.Sleep(backoff)
+		} else if transitionedToOpen && c.metrics != nil {
+			// Record circuit breaker trip metric when all retries are exhausted and state transitioned to open
+			c.metrics.RecordCircuitBreakerTrip()
 		}
 	}
 
-	c.metrics.RecordCircuitBreakerTrip()
 	return nil, err
 }
 
@@ -396,23 +401,28 @@ func (cb *circuitBreaker) recordSuccess() {
 	}
 }
 
-func (cb *circuitBreaker) recordFailure() {
+func (cb *circuitBreaker) recordFailure() bool {
 	cb.mu.Lock()
 	defer cb.mu.Unlock()
 
+	transitionedToOpen := false
 	switch cb.state {
 	case closed:
 		cb.failures++
 		if cb.failures >= cb.failThreshold {
 			cb.state = open
 			cb.openSince = time.Now()
+			transitionedToOpen = true
 		}
 	case halfOpen:
 		cb.state = open
 		cb.openSince = time.Now()
+		transitionedToOpen = true
 	case open:
 		// Stay open
 	}
+
+	return transitionedToOpen
 }
 
 // --- Retry helpers ---