Merge pull request #224 from SimJunYou/piholePrivacy

DNS Stats widget - fix Pihole privacy edge case

internal/feed/pihole.go

@@ -1,6 +1,7 @@
 package feed
 
 import (
+	"encoding/json"
 	"errors"
 	"log/slog"
 	"net/http"
@@ -14,10 +15,30 @@ type piholeStatsResponse struct {
 	BlockedQueries    int                     `json:"ads_blocked_today"`
 	BlockedSeries     map[int64]int           `json:"ads_over_time"`
 	BlockedPercentage float64                 `json:"ads_percentage_today"`
-	TopBlockedDomains map[string]int `json:"top_ads"`
+	TopBlockedDomains piholeTopBlockedDomains `json:"top_ads"`
 	DomainsBlocked    int                     `json:"domains_being_blocked"`
 }
 
+// If user has some level of privacy enabled on Pihole, `json:"top_ads"` is an empty array
+// Use custom unmarshal behavior to avoid not getting the rest of the valid data when unmarshalling
+type piholeTopBlockedDomains map[string]int
+
+func (p *piholeTopBlockedDomains) UnmarshalJSON(data []byte) error {
+	// NOTE: do not change to piholeTopBlockedDomains type here or it will cause a stack overflow
+	// because of the UnmarshalJSON method getting called recursively
+	temp := make(map[string]int)
+
+	err := json.Unmarshal(data, &temp)
+
+	if err != nil {
+		*p = make(piholeTopBlockedDomains)
+	} else {
+		*p = temp
+	}
+
+	return nil
+}
+
 func FetchPiholeStats(instanceURL, token string) (*DNSStats, error) {
 	if token == "" {
 		return nil, errors.New("missing API token")