fix: allow pleaseNotify when ping frequency check triggers

When a subscriber calls pleaseNotify, the ping() call could fail with a
frequency throttle error even though the feed was recently validated.
Add error codes to ErrorResponse and treat PING_TOO_RECENT as success
in pleaseNotify since the feed was already confirmed accessible.

Author: andrewshell

services/error-response.js

@@ -1,5 +1,6 @@
-function ErrorResponse(message) {
+function ErrorResponse(message, code) {
     this.message = message;
+    this.code = code;
 }
 
 ErrorResponse.prototype = Object.create(Error.prototype);

services/ping.js

@@ -15,7 +15,7 @@ async function checkPingFrequency(resource) {
         const dayjs = await getDayjs();
         ctsecs = dayjs().diff(resource.whenLastCheck, 'seconds');
         if (ctsecs < minsecs) {
-            throw new ErrorResponse(appMessage.error.ping.tooRecent(minsecs, ctsecs));
+            throw new ErrorResponse(appMessage.error.ping.tooRecent(minsecs, ctsecs), 'PING_TOO_RECENT');
         }
     }
 }

services/please-notify.js

@@ -80,8 +80,10 @@ async function pleaseNotify(notifyProcedure, apiurl, protocol, urlList, diffDoma
         urlList.map(async(resourceUrl) => {
             try {
                 await ping(resourceUrl);
-            } catch {
-                throw new ErrorResponse(appMessages.error.subscription.readResource(resourceUrl));
+            } catch (err) {
+                if (err.code !== 'PING_TOO_RECENT') {
+                    throw new ErrorResponse(appMessages.error.subscription.readResource(resourceUrl));
+                }
             }
             await notifyApiUrl(notifyProcedure, apiurl, protocol, resourceUrl, diffDomain);
         })