feat(plugins): Added new plugin hook sender:responseError, allow configuratble defer times (#360)

Author: andris9

lib/sender.js

@@ -25,10 +25,10 @@ const base32 = require('base32.js');
 // handle DNS resolving
 require('./ip-tools');
 
-const ttlMinutes = [
+const DEFAULT_DEFER_TIMES = [
     5 /* 5 */, 7 /* 12 */, 8 /* 20 */, 25 /* 45 */, 75 /* 2h */, 120 /* 4h */, 240 /* 8h */, 240 /* 12h */, 240 /* 16h */, 240 /* 20h */, 240 /* 24h */,
     240 /* 28h */, 240 /* 32h */, 240 /* 36h */, 240 /* 40h */, 240 /* 44h */, 240 /* 48h */
-];
+].map(v => v * 60 * 1000);
 
 const POLICY_RESPONSE = '550 Failed to establish a TLS connection to the MX server as requested by policy';
 
@@ -143,7 +143,9 @@ class Sender extends EventEmitter {
                 return;
             }
             responseSent = true;
-            this.handleResponseError(delivery, connection, err, continueSending);
+            plugins.handler.runHooks('sender:responseError', [delivery, connection, err], () => {
+                this.handleResponseError(delivery, connection, err, continueSending);
+            });
         };
 
         this.sendCommand('GET', (err, delivery) => {
@@ -723,9 +725,10 @@ class Sender extends EventEmitter {
             bounce.action = 'reject';
         }
 
-        if (bounce.action !== 'reject' && deferredCount < ttlMinutes.length) {
-            //let ttl = Math.min(Math.pow(5, Math.min(deferredCount + 1, 4)), 180) * 60 * 1000;
-            let ttl = ttlMinutes[deferredCount] * 60 * 1000;
+        const deferTimes = delivery.deferTimes && Array.isArray(delivery.deferTimes) && delivery.deferTimes.length ? delivery.deferTimes : DEFAULT_DEFER_TIMES;
+
+        if (bounce.action !== 'reject' && deferredCount < deferTimes.length) {
+            const ttl = deferTimes[deferredCount];
             log.info(
                 this.logName,
                 'id=%s %s.%s DEFERRED[%s] from=%s to=%s src=%s mx=%s id=%s (%s)',