Filtering UP instances by default. Added tests.

CHANGES.md

@@ -0,0 +1,2 @@
+## 3.0.0
+  - Populate registry cache with instances that have a status of `UP`, `filterUpInstances` can be set to `false` to disable.

README.md

@@ -123,6 +123,19 @@ If your have multiple availability zones and your DNS entries set up according t
 
 This will cause the client to perform a DNS lookup using `config.eureka.host` and `config.eureka.ec2Region`. The naming convention for the DNS TXT records required for this to function is also described in the Wiki article above.
 
+## Configuration Options
+option | default value | description
+---- | --- | ---
+`logger` | console logging | logger implementation for the client to use
+`eureka.heartbeatInterval` | `30000` | milliseconds to wait between heartbeats
+`eureka.registryFetchInterval` | `30000` | milliseconds to wait between registry fetches
+`eureka.fetchRegistry` | `true` | enable/disable registry fetching
+`eureka.filterUpInstances` | `true` | enable/disable filtering of instances with status === `UP`
+`eureka.servicePath` | `/eureka/v2/apps/` | path to eureka REST service
+`eureka.ssl` | `false` | enable SSL communication with Eureka server
+`eureka.useDns` | `false` | look up Eureka server using DNS, see [Looking up Eureka Servers in AWS using DNS](#looking-up-eureka-servers-in-aws-using-dns)
+`eureka.fetchMetadata` | `true` | fetch AWS metadata when in AWS environment, see [Configuring for AWS environments](#configuring-for-aws-environments)
+`eureka.useLocalMetadata` | `false` | use local IP and local hostname from metadata when in an AWS environment.
 
 ## Debugging
 

src/EurekaClient.js

@@ -340,19 +340,27 @@ export default class Eureka {
 
   /*
     Transforms the given application and places in client cache. If an application
-      has a single instance, the instance is placed into the cache as an array of one
+    has a single instance, the instance is placed into the cache as an array of one
    */
   transformApp(app, cache) {
     if (app.instance.length) {
-      cache.app[app.name.toUpperCase()] = app.instance;
-      cache.vip[app.instance[0].vipAddress] = app.instance;
-    } else {
+      const instances = app.instance.filter((instance) => (this.validateInstance(instance)));
+      cache.app[app.name.toUpperCase()] = instances;
+      cache.vip[app.instance[0].vipAddress] = instances;
+    } else if (this.validateInstance(app.instance)) {
       const instances = [app.instance];
       cache.vip[app.instance.vipAddress] = instances;
       cache.app[app.name.toUpperCase()] = instances;
     }
   }
 
+  /*
+    Returns true if instance filtering is disabled, or if the instance is UP
+  */
+  validateInstance(instance) {
+    return (!this.config.eureka.filterUpInstances || instance.status === 'UP');
+  }
+
   /*
     Fetches the metadata using the built-in client and updates the instance
     configuration with the hostname and IP address. If the value of the config

src/defaultConfig.js

@@ -4,6 +4,7 @@ export default {
     heartbeatInterval: 30000,
     registryFetchInterval: 30000,
     fetchRegistry: true,
+    filterUpInstances: true,
     servicePath: '/eureka/v2/apps/',
     ssl: false,
     useDns: false,

test/EurekaClient.test.js

@@ -512,9 +512,9 @@ describe('Eureka client', () => {
       registry = {
         applications: { application: {} },
       };
-      instance1 = { host: '127.0.0.1', port: 1000, vipAddress: 'vip1' };
-      instance2 = { host: '127.0.0.2', port: 2000, vipAddress: 'vip2' };
-      instance3 = { host: '127.0.0.2', port: 2000, vipAddress: 'vip2' };
+      instance1 = { host: '127.0.0.1', port: 1000, vipAddress: 'vip1', status: 'UP' };
+      instance2 = { host: '127.0.0.2', port: 2000, vipAddress: 'vip2', status: 'UP' };
+      instance3 = { host: '127.0.0.2', port: 2000, vipAddress: 'vip2', status: 'UP' };
       app1 = { name: 'theapp', instance: instance1 };
       app2 = { name: 'theapptwo', instance: [instance2, instance3] };
       client = new Eureka(config);
@@ -548,6 +548,7 @@ describe('Eureka client', () => {
     let app;
     let instance1;
     let instance2;
+    let downInstance;
     let theVip;
     let cache;
     beforeEach(() => {
@@ -556,8 +557,9 @@ describe('Eureka client', () => {
       });
       client = new Eureka(config);
       theVip = 'theVip';
-      instance1 = { host: '127.0.0.1', port: 1000, vipAddress: theVip };
-      instance2 = { host: '127.0.0.2', port: 2000, vipAddress: theVip };
+      instance1 = { host: '127.0.0.1', port: 1000, vipAddress: theVip, status: 'UP' };
+      instance2 = { host: '127.0.0.2', port: 2000, vipAddress: theVip, status: 'UP' };
+      downInstance = { host: '127.0.0.2', port: 2000, vipAddress: theVip, status: 'DOWN' };
       app = { name: 'theapp' };
       cache = { app: {}, vip: {} };
     });
@@ -575,6 +577,25 @@ describe('Eureka client', () => {
       expect(cache.app[app.name.toUpperCase()].length).to.equal(2);
       expect(cache.vip[theVip].length).to.equal(2);
     });
+
+    it('should filter UP instances by default', () => {
+      app.instance = [instance1, instance2, downInstance];
+      client.transformApp(app, cache);
+      expect(cache.app[app.name.toUpperCase()].length).to.equal(2);
+      expect(cache.vip[theVip].length).to.equal(2);
+    });
+
+    it('should not filter UP instances when filterUpInstances === false', () => {
+      config = makeConfig({
+        instance: { dataCenterInfo: { name: 'Amazon' } },
+        eureka: { filterUpInstances: false },
+      });
+      client = new Eureka(config);
+      app.instance = [instance1, instance2, downInstance];
+      client.transformApp(app, cache);
+      expect(cache.app[app.name.toUpperCase()].length).to.equal(3);
+      expect(cache.vip[theVip].length).to.equal(3);
+    });
   });
 
   describe('addInstanceMetadata()', () => {