Add indexer cache with River queue for scheduled refresh

internal/indexer/cache.go

@@ -0,0 +1,79 @@
+package indexer
+
+import (
+	"sync"
+	"time"
+
+	"github.com/rs/zerolog/log"
+)
+
+type CacheEntry struct {
+	Key             string
+	URL             string
+	Result          SearchResult
+	CreatedAt       time.Time
+	TTL             time.Duration
+	RefreshInterval time.Duration
+}
+
+func (e *CacheEntry) IsExpired() bool {
+	return time.Now().After(e.CreatedAt.Add(e.TTL))
+}
+
+type IndexerCache struct {
+	entries map[string]*CacheEntry
+	mu      sync.RWMutex
+}
+
+func NewIndexerCache() *IndexerCache {
+	return &IndexerCache{
+		entries: make(map[string]*CacheEntry),
+	}
+}
+
+func (c *IndexerCache) Get(key string) (*CacheEntry, bool) {
+	c.mu.RLock()
+	defer c.mu.RUnlock()
+
+	entry, ok := c.entries[key]
+	if !ok {
+		log.Trace().Str("key", key).Msg("cache miss")
+		return nil, false
+	}
+
+	if entry.IsExpired() {
+		log.Trace().Str("key", key).Msg("cache expired")
+		return nil, false
+	}
+
+	log.Trace().Str("key", key).Int("items", len(entry.Result.Items)).Msg("cache hit")
+	return entry, true
+}
+
+func (c *IndexerCache) Add(entry CacheEntry) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	c.entries[entry.Key] = &entry
+	log.Debug().Str("key", entry.Key).Int("items", len(entry.Result.Items)).Dur("ttl", entry.TTL).Dur("refresh", entry.RefreshInterval).Msg("cache entry added")
+}
+
+func (c *IndexerCache) Update(key string, result SearchResult) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	if entry, ok := c.entries[key]; ok {
+		entry.Result = result
+		log.Debug().Str("key", key).Int("items", len(result.Items)).Msg("cache entry updated")
+	} else {
+		log.Warn().Str("key", key).Msg("cache update for missing entry")
+	}
+}
+
+func (c *IndexerCache) Remove(key string) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	delete(c.entries, key)
+	log.Debug().Str("key", key).Msg("cache entry removed")
+}