fetcher refact

lib/fetcher.go

@@ -15,9 +15,25 @@ type Entry struct {
 
 // Fetcher is the interface for a fetcher.
 type Fetcher interface {
+	Name() string
 	Fetch() []Entry
 }
 
+// BaseFetcher contains common fields for all fetchers.
+type BaseFetcher struct {
+	BaseURL string
+	Token   string
+	Cache   *Cache
+}
+
+// TryCreateEntry checks the cache and creates an Entry if the value has changed.
+func (b *BaseFetcher) TryCreateEntry(cacheKey, cacheValue, title, url string) *Entry {
+	if b.Cache.TryUpdate(cacheKey, cacheValue) {
+		return &Entry{Title: title, URL: url}
+	}
+	return nil
+}
+
 // FetcherRequest represents a common HTTP request configuration.
 type FetcherRequest struct {
 	BaseURL string