rename redisNotAvailableLogged, simplify conditional logic

src/backend/lib/queue.js

@@ -9,7 +9,11 @@ const { logger } = require('../utils/logger');
 
 const client = createRedisClient();
 const subscriber = createRedisClient();
-let redisErrorLogged = false;
+
+/**
+ * Tracks whether an informative message has been logged following a Redis connection failure
+ */
+let redisConnectionRefusalLogged = false;
 
 /**
  * Create a Queue with the given `name` (String).
@@ -32,15 +36,13 @@ function createQueue(name) {
   })
     .on('error', err => {
       // An error occurred
-      if (err.code === 'ECONNREFUSED') {
-        if (!redisErrorLogged) {
-          logger.error(
-            '\n\n\t💡  It appears that Redis is not running on your machine.',
-            '\n\t   Please see our documentation for how to install and run Redis:',
-            '\n\t   https://github.com/Seneca-CDOT/telescope/blob/master/docs/CONTRIBUTING.md\n'
-          );
-          redisErrorLogged = true;
-        }
+      if (err.code === 'ECONNREFUSED' && !redisConnectionRefusalLogged) {
+        logger.error(
+          '\n\n\t💡  It appears that Redis is not running on your machine.',
+          '\n\t   Please see our documentation for how to install and run Redis:',
+          '\n\t   https://github.com/Seneca-CDOT/telescope/blob/master/docs/CONTRIBUTING.md\n'
+        );
+        redisConnectionRefusalLogged = true;
       } else {
         logger.error({ err }, `Queue ${name} error`);
       }