Merge pull request cravall#28 from cvallance/ocd-changes-to-pr-25

Just a couple of optimizations and style changes to PR cravall#25.
young-0 · Apr 3, 2017 · 3b1eae7 · 3b1eae7
2 parents 36b78a0 + e4061a2
commit 3b1eae7
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Showing 2 changed files with 48 additions and 36 deletions.
diff --git a/src/lib/config.js b/src/lib/config.js
@@ -1,3 +1,5 @@
+var dns = require('dns');
+
 var getMongoPodLabels = function() {
   return process.env.MONGO_SIDECAR_POD_LABELS || false;
 };
@@ -31,25 +33,36 @@ var getK8sClusterDomain = function() {
   var domain = process.env.KUBERNETES_CLUSTER_DOMAIN || "cluster.local";
   verifyCorrectnessOfDomain(domain);
   return domain;
+};
 
-  /**
-   * Calls a reverse DNS lookup to ensure that the given custom domain name matches the actual one.
-   * Raises a console warning if that is not the case.
-   * @param clusterDomain the domain to verify.
-   */
-  function verifyCorrectnessOfDomain(clusterDomain) {
-    var dns = require('dns');
-    if(clusterDomain && dns.getServers() && dns.getServers().length > 0) {
-      // In the case that we can resolve the DNS servers, we get the first and try to retrieve its host.
-      dns.reverse(dns.getServers()[0], function(err, host) {
-        if(err || host.length < 1 || !host[0].endsWith(clusterDomain)) {
-          console.warn("Possibly wrong cluster domain name! Detected '%s' but expected similar to: %s",  clusterDomain, host);
-        } else {
-          console.log("The cluster domain '%s' was successfully verified.", clusterDomain)
-        }
-      });
-    }
+/**
+ * Calls a reverse DNS lookup to ensure that the given custom domain name matches the actual one.
+ * Raises a console warning if that is not the case.
+ * @param clusterDomain the domain to verify.
+ */
+var verifyCorrectnessOfDomain = function(clusterDomain) {
+  if (!clusterDomain) {
+    return;
   }
+
+  var servers = dns.getServers();
+  if (!servers || !servers.length) {
+    console.log("dns.getServers() didn't return any results when verifying the cluster domain '%s'.", clusterDomain);
+    return;
+  }
+
+  // In the case that we can resolve the DNS servers, we get the first and try to retrieve its host.
+  dns.reverse(servers[0], function(err, host) {
+    if (err) {
+      console.warn("Error occurred trying to verify the cluster domain '%s'",  clusterDomain);
+    }
+    else if (host.length < 1 || !host[0].endsWith(clusterDomain)) {
+      console.warn("Possibly wrong cluster domain name! Detected '%s' but expected similar to '%s'",  clusterDomain, host);
+    }
+    else {
+      console.log("The cluster domain '%s' was successfully verified.", clusterDomain);
+    }
+  });
 };
 
 /**

diff --git a/src/lib/worker.js b/src/lib/worker.js
@@ -141,8 +141,8 @@ var primaryWork = function(db, pods, members, shouldForce, done) {
   }
 
   if (addrToAdd.length || addrToRemove.length) {
-    console.log('Addresses to add:   ', addrToAdd);
-    console.log('Addresses to remove:', addrToRemove);
+    console.log('Addresses to add:    ', addrToAdd);
+    console.log('Addresses to remove: ', addrToRemove);
 
     mongo.addNewReplSetMembers(db, addrToAdd, addrToRemove, shouldForce, done);
     return;
@@ -190,7 +190,7 @@ var notInReplicaSet = function(db, pods, done) {
       var primary = pods[0]; // After the sort election, the 0-th pod should be the primary.
       var primaryStableNetworkAddressAndPort = getPodStableNetworkAddressAndPort(primary);
       // Prefer the stable network ID over the pod IP, if present.
-      var primaryAddressAndPort = primaryStableNetworkAddressAndPort ? primaryStableNetworkAddressAndPort : hostIpAndPort;
+      var primaryAddressAndPort = primaryStableNetworkAddressAndPort || hostIpAndPort;
       mongo.initReplSet(db, primaryAddressAndPort, done);
       return;
     }
@@ -234,12 +234,12 @@ var addrToAddLoop = function(pods, members) {
     }
 
     var podIpAddr = getPodIpAddressAndPort(pod);
-    var podStableNetworkAdd = getPodStableNetworkAddressAndPort(pod);
+    var podStableNetworkAddr = getPodStableNetworkAddressAndPort(pod);
     var podInRs = false;
 
     for (var j in members) {
       var member = members[j];
-      if ((podIpAddr && member.name === podIpAddr) || (podStableNetworkAdd && member.name === podStableNetworkAdd)) {
+      if (member.name === podIpAddr || member.name === podStableNetworkAddr) {
         /* If we have the pod's ip or the stable network address already in the config, no need to read it. Checks both the pod IP and the
         * stable network ID - we don't want any duplicates - either one of the two is sufficient to consider the node present. */
         podInRs = true;
@@ -249,7 +249,7 @@ var addrToAddLoop = function(pods, members) {
 
     if (!podInRs) {
       // If the node was not present, we prefer the stable network ID, if present.
-      var addrToUse = podStableNetworkAdd ? podStableNetworkAdd : podIpAddr;
+      var addrToUse = podStableNetworkAddr || podIpAddr;
       addrToAdd.push(addrToUse);
     }
   }
@@ -258,15 +258,15 @@ var addrToAddLoop = function(pods, members) {
 
 /**
  * @param pod this is the Kubernetes pod, containing the info.
- * @returns podIp the pod's IP address with the default port of 27017 (retrieved from the config) attached at the end. Example
+ * @returns string - podIp the pod's IP address with the port from config attached at the end. Example
  * WWW.XXX.YYY.ZZZ:27017. It returns undefined, if the data is insufficient to retrieve the IP address.
  */
 var getPodIpAddressAndPort = function(pod) {
-  var podIpAddress = undefined;
-  if (pod && pod.status && pod.status.podIP) {
-    podIpAddress = pod.status.podIP + ":" + config.mongoPort;
+  if (!pod || !pod.status || !pod.status.podIP) {
+    return;
   }
-  return podIpAddress;
+
+  return pod.status.podIP + ":" + config.mongoPort;
 };
 
 /**
@@ -275,17 +275,16 @@ var getPodIpAddressAndPort = function(pod) {
  * <a href="https://kubernetes.io/docs/concepts/abstractions/controllers/statefulsets/#stable-network-id">Stateful Set documentation</a>
  * for more details. If those are not set, then simply the pod's IP is returned.
  * @param pod the Kubernetes pod, containing the information from the k8s client.
- * @returns stableNetworkAddress the k8s MongoDB stable network address, or undefined.
+ * @returns string the k8s MongoDB stable network address, or undefined.
  */
 var getPodStableNetworkAddressAndPort = function(pod) {
-  var podStableNetworkAddress = undefined;
-  if (config.k8sMongoServiceName && pod && pod.metadata && pod.metadata.name && pod.metadata.namespace) {
-    var clusterDomain = config.k8sClusterDomain;
-    var mongoPort = config.mongoPort;
-    podStableNetworkAddress = pod.metadata.name + "." + config.k8sMongoServiceName + "." + pod.metadata.namespace + ".svc." +
-      clusterDomain + ":" + mongoPort;
+  if (!config.k8sMongoServiceName || !pod || !pod.metadata || !pod.metadata.name || !pod.metadata.namespace) {
+    return;
   }
-  return podStableNetworkAddress;
+
+  var clusterDomain = config.k8sClusterDomain;
+  var mongoPort = config.mongoPort;
+  return pod.metadata.name + "." + config.k8sMongoServiceName + "." + pod.metadata.namespace + ".svc." + clusterDomain + ":" + mongoPort;
 };
 
 module.exports = {