Remove hostedZoneID configuration parameter. This is no longer requir…

…ed to be set upfront. Instead the hostedZoneID will be discovered in route53 based on the ddnsHostName config param

README.md

@@ -18,8 +18,6 @@ Modify the following configuration parameters in config.json:
 
 `ddnsHostName` - Domain name, owned in Route 53, that you want to keep updated with a dynamic IP.
 
-`ddnsHostedZoneID` - Route53 hostedZoneID of ddnsHostName referenced above
-
 `notificationTopicARN` - TopicARN, in SNS, that you wish to receive notifications on.  Notifications are sent upon a successful DDNS update or failed attempt.
 
 
@@ -50,5 +48,3 @@ POST 'homeIp' JSON to API endpoint with AWS IAM Signature.  User api user is cre
 
 ## TODO
 1) Eliminate topicARN requirement, and instead send to arbitrary email and/or SMS 
-
-2) eliminate HostedZoneID requirement and install to search in route53 based on ddnsHostName

config.json

@@ -1,6 +1,5 @@
 {
     "apiDomainName": "",
     "ddnsHostName": "",
-    "ddnsHostedZoneID": "",
     "notificationTopicARN": ""
 }

package.json

@@ -10,7 +10,6 @@
   "author": "John Belisle",
   "license": "ISC",
   "devDependencies": {
-    "serverless-aws-alias": "^1.7.1",
     "serverless-domain-manager": "^3.2.1"
   }
 }

serverless.yml

@@ -24,7 +24,6 @@ custom:
 
 plugins:
   - serverless-domain-manager  
-  # - serverless-aws-alias
 
 # you can add packaging information here
 #package:
@@ -50,7 +49,6 @@ functions:
     memorySize: 128
     environment:
       DNS_HOST_NAME: ${self:custom.config.ddnsHostName}
-      HOSTED_ZONE_ID: ${self:custom.config.ddnsHostedZoneID}
       TOPIC_ARN: ${self:custom.config.notificationTopicARN}
     events:      
       - http:

src/scripts/updateDNSScript.js

@@ -1,23 +1,24 @@
 'use strict'
 
 class UpdateDNSScript {
-    constructor(route53, notificationScript, hostedZoneID, hostName) {
+    constructor(route53, notificationScript, hostName) {
         this.route53 = route53;
-        this.hostedZoneID = hostedZoneID;
         this.hostName = hostName;
         this.notificationScript = notificationScript;
     }
 
 
     async update(newIP) {
-        const currentIP = await this.getCurrentIP();
-        console.log("currentIP in route53 = " + currentIP);
+        const route53HostedZoneId = await this.getRoute53HostedZoneId();
+        console.log("found matching hostedZoneId: " + route53HostedZoneId + " for hostName: " + this.hostName);
+        const currentIP = await this.getCurrentIP(route53HostedZoneId, this.hostName);
+        console.log("currentIP for hostName: " + this.hostName + " in route53 = " + currentIP);
         if (newIP === currentIP) {
             console.log("IP has not changed for hostName: [" + this.hostName + "], exiting...");
             return "Success - No Change";
         } else {
             console.log("IP has changed for hostName: [" + this.hostName + "], issuing recordSet UPSERT");
-            const updateRequest = this.getUpdateRequest(this.hostedZoneID, this.hostName, newIP);
+            const updateRequest = this.getUpdateRequest(route53HostedZoneId, this.hostName, newIP);
             try {
                 const result = await this.route53.changeResourceRecordSets(updateRequest).promise();
                 console.log("Successfully changed [" + this.hostName + "] IP to " + newIP + ".  Result from route53 changeResourceRecordSets:" + JSON.stringify(result, null, 2));
@@ -32,11 +33,11 @@ class UpdateDNSScript {
         }
     }
 
-    async getCurrentIP() {
-        console.log("QUerying route53 for record set with hostName: " + this.hostName);
+    async getCurrentIP(hostedZoneID, hostName) {
+        console.log("Querying route53 for record set with hostName: " + hostName);
         var params = {
-            HostedZoneId: this.hostedZoneID,
-            StartRecordName: this.hostName,
+            HostedZoneId: hostedZoneID,
+            StartRecordName: hostName,
             MaxItems: '1'
         };
         var data = await this.route53.listResourceRecordSets(params).promise();
@@ -65,6 +66,55 @@ class UpdateDNSScript {
             }
         };
     }
+
+
+    /**
+     * Gets Route53 HostedZoneId from from AWS
+     */
+    async getRoute53HostedZoneId() {
+        let hostedZoneData;
+        const givenDomainNameReverse = this.hostName.split(".").reverse();
+
+        try {
+            hostedZoneData = await this.route53.listHostedZones({}).promise();
+            const targetHostedZone = hostedZoneData.HostedZones
+                .filter((hostedZone) => {
+                    let hostedZoneName;
+                    if (hostedZone.Name.endsWith(".")) {
+                        hostedZoneName = hostedZone.Name.slice(0, -1);
+                    } else {
+                        hostedZoneName = hostedZone.Name;
+                    }
+                    const hostedZoneNameReverse = hostedZoneName.split(".").reverse();
+
+                    if (givenDomainNameReverse.length === 1
+                        || (givenDomainNameReverse.length >= hostedZoneNameReverse.length)) {
+                        for (let i = 0; i < hostedZoneNameReverse.length; i += 1) {
+                            if (givenDomainNameReverse[i] !== hostedZoneNameReverse[i]) {
+                                return false;
+                            }
+                        }
+                        return true;
+                    }
+                    return false;
+                })
+                .sort((zone1, zone2) => zone2.Name.length - zone1.Name.length)
+                .shift();
+
+            if (targetHostedZone) {
+                const hostedZoneId = targetHostedZone.Id;
+                // Extracts the hostzone Id
+                const startPos = hostedZoneId.indexOf("e/") + 2;
+                const endPos = hostedZoneId.length;
+                return hostedZoneId.substring(startPos, endPos);
+            }
+        } catch (err) {
+            console.log(err, err.stack);
+            throw new Error(`Error: Unable to list hosted zones in Route53.\n${err}`);
+        }
+        throw new Error(`Error: Could not find hosted zone "${this.hostName}"`);
+    };
+
 }
 
 module.exports = UpdateDNSScript;

src/updateHomeDNS.js

@@ -13,8 +13,7 @@ const NotificationScript = require('./scripts/notificationScript');
 const notificationScript = new NotificationScript(sns, process.env.TOPIC_ARN);
 
 const UpdateDNSScript = require('./scripts/updateDNSScript');
-const updateDNSScript = new UpdateDNSScript(route53, notificationScript, process.env.HOSTED_ZONE_ID, process.env.DNS_HOST_NAME);
-// const updateDNSScript = require('./scripts/updateDNSScript')(route53, notificationScript, process.env.HOSTED_ZONE_ID, process.env.DNS_HOST_NAME);
+const updateDNSScript = new UpdateDNSScript(route53, notificationScript, process.env.DNS_HOST_NAME);
 
 
 
@@ -41,21 +40,4 @@ async function processRequest(event) {
   var homeIp = requestBody['homeIp'];
   var responseMsg = await updateDNSScript.update(homeIp);
   return responses.success(responseMsg);
-
-
 }
-
-
-
-
-  // return {
-  //   statusCode: 200,
-  //   body: JSON.stringify({
-  //     message: 'Go Serverless v1.0! Your function executed successfully!',
-  //     input: event,
-  //   }),
-  // };
-
-  // Use this code if you don't use the http event with the LAMBDA-PROXY integration
-  // return { message: 'Go Serverless v1.0! Your function executed successfully!', event };
-// };