Merge duplicate phishCache/phishTankCache into shared feedCache

checker/phishtank.go

@@ -10,7 +10,6 @@ import (
 	"net/http"
 	"strconv"
 	"strings"
-	"sync"
 	"time"
 
 	sdk "git.happydns.org/checker-sdk-go/checker"
@@ -21,7 +20,7 @@ const (
 	phishTankDefaultTTL = 12 * time.Hour
 )
 
-var phishTankGlobalCache = newPhishTankCache()
+var phishTankGlobalCache = newFeedCache(phishTankDefaultTTL, phishTankFetch)
 
 func init() { Register(&phishTankSource{}) }
 
@@ -107,71 +106,8 @@ func (*phishTankSource) Diagnose(res SourceResult) Diagnosis {
 	}
 }
 
-// ---------- feed cache ----------
-
-type phishTankCache struct {
-	mu            sync.Mutex
-	urls          []string
-	byHost        map[string][]string
-	fetchedAt     time.Time
-	lastAttemptAt time.Time
-	refreshing    bool
-	ttl           time.Duration
-	failBackoff   time.Duration
-}
-
-func newPhishTankCache() *phishTankCache {
-	return &phishTankCache{
-		ttl:         phishTankDefaultTTL,
-		failBackoff: 1 * time.Minute,
-	}
-}
-
-func (c *phishTankCache) setTTL(d time.Duration) {
-	c.mu.Lock()
-	c.ttl = d
-	c.mu.Unlock()
-}
-
-func (c *phishTankCache) lookup(ctx context.Context, domain string) (urls []string, size int, fetchedAt time.Time, err error) {
-	domain = strings.ToLower(strings.TrimSuffix(domain, "."))
-
-	c.mu.Lock()
-	stale := c.byHost == nil || time.Since(c.fetchedAt) > c.ttl
-	doRefresh := stale && !c.refreshing && time.Since(c.lastAttemptAt) > c.failBackoff
-	if doRefresh {
-		c.refreshing = true
-	}
-	c.mu.Unlock()
-
-	if doRefresh {
-		newURLs, newByHost, ferr := c.fetch(ctx)
-		c.mu.Lock()
-		c.refreshing = false
-		c.lastAttemptAt = time.Now()
-		if ferr == nil {
-			c.urls = newURLs
-			c.byHost = newByHost
-			c.fetchedAt = c.lastAttemptAt
-		} else {
-			err = ferr
-		}
-		c.mu.Unlock()
-	}
-
-	c.mu.Lock()
-	for host, hostURLs := range c.byHost {
-		if host == domain || strings.HasSuffix(host, "."+domain) {
-			urls = append(urls, hostURLs...)
-		}
-	}
-	size = len(c.urls)
-	fetchedAt = c.fetchedAt
-	c.mu.Unlock()
-	return urls, size, fetchedAt, err
-}
-
-func (c *phishTankCache) fetch(ctx context.Context) ([]string, map[string][]string, error) {
+// phishTankFetch downloads and parses the PhishTank gzip-compressed CSV feed.
+func phishTankFetch(ctx context.Context) ([]string, map[string][]string, error) {
 	reqCtx, cancel := context.WithTimeout(ctx, 120*time.Second)
 	defer cancel()