admin: Copy challenge.json from sync to distsettings

admin/main.go

@@ -142,6 +142,20 @@ func main() {
 			log.Fatal("Unable to initialize the importer:", err)
 		}
 		log.Println("Using", sync.GlobalImporter.Kind())
+
+		// Update distributed challenge.json
+		challengeinfo, err := sync.GetFileContent(sync.GlobalImporter, settings.ChallengeFile)
+		if err == nil {
+			if fd, err := os.Create(path.Join(settings.SettingsDir, settings.ChallengeFile)); err != nil {
+				log.Fatal("Unable to open SETTINGS/challenge.json:", err)
+			} else {
+				fd.Write([]byte(challengeinfo))
+				err = fd.Close()
+				if err != nil {
+					log.Fatal("Something went wrong during SETTINGS/challenge.json writing:", err)
+				}
+			}
+		}
 	}
 
 	// Sanitize options