Retry 400s

src/EurekaClient.js

@@ -606,7 +606,7 @@ export default class Eureka extends EventEmitter {
       // Perform retry if request failed and we have attempts left
       const responseInvalid = response
         && response.statusCode
-        && String(response.statusCode)[0] === '5';
+        && this.shouldRetry(response.statusCode)
 
       if ((error || responseInvalid) && retryAttempt < this.config.eureka.maxRetries) {
         const nextRetryDelay = this.config.eureka.requestRetryDelay * (retryAttempt + 1);
@@ -622,4 +622,14 @@ export default class Eureka extends EventEmitter {
     });
   }
 
+  shouldRetry(statusCode) {
+    //retryableStatusCodes is a comma separated list of ranges (ie 401-403,500-502)
+    //so go through each range and check if the status code falls inside of any of them
+    const retryableRanges = this.config.eureka.retryableStatusCodes.split(",")
+    return retryableRanges
+      .some(range => {
+        const [lower, upper] = range.split("-")
+        return (statusCode >= parseInt(lower) && statusCode <= parseInt(upper))
+      })
+  }
 }

src/defaultConfig.js

@@ -7,6 +7,7 @@ export default {
     registryFetchInterval: 30000,
     maxRetries: 3,
     requestRetryDelay: 500,
+    retryableStatusCodes: "500-599",
     fetchRegistry: true,
     filterUpInstances: true,
     servicePath: '/eureka/v2/apps/',

test/EurekaClient.test.js

@@ -1099,7 +1099,7 @@ describe('Eureka client', () => {
       const overrides = {
         eureka: {
           serviceUrls: {
-            default: ['http://serverA', 'http://serverB'],
+            default: ['http://serverA', 'http://serverB', 'http://serverC'],
           },
           maxRetries: 3,
           requestRetryDelay: 0,
@@ -1109,7 +1109,8 @@ describe('Eureka client', () => {
       const client = new Eureka(config);
       const requestStub = sinon.stub(request, 'get');
       requestStub.onCall(0).yields(null, { statusCode: 500 }, null);
-      requestStub.onCall(1).yields(null, { statusCode: 200 }, null);
+      requestStub.onCall(1).yields(null, { statusCode: 400 }, null);
+      requestStub.onCall(2).yields(null, { statusCode: 200 }, null);
       client.eurekaRequest({ uri: '/path' }, (error) => {
         expect(error).to.be.null;
         expect(requestStub).to.be.calledTwice;
@@ -1118,6 +1119,32 @@ describe('Eureka client', () => {
         done();
       });
     });
+    it('should retry next server on configured request failure', (done) => {
+      const overrides = {
+        eureka: {
+          serviceUrls: {
+            default: ['http://serverA', 'http://serverB', 'http://serverC'],
+          },
+          maxRetries: 3,
+          requestRetryDelay: 0,
+          retryableStatusCodes: "400-404,500-504"
+        },
+      };
+      const config = makeConfig(overrides);
+      const client = new Eureka(config);
+      const requestStub = sinon.stub(request, 'get');
+      requestStub.onCall(0).yields(null, { statusCode: 500 }, null);
+      requestStub.onCall(1).yields(null, { statusCode: 400 }, null);
+      requestStub.onCall(2).yields(null, { statusCode: 200 }, null);
+      client.eurekaRequest({ uri: '/path' }, (error) => {
+        expect(error).to.be.null;
+        expect(requestStub).to.be.calledThrice;
+        expect(requestStub.args[0][0]).to.have.property('baseUrl', 'http://serverA');
+        expect(requestStub.args[1][0]).to.have.property('baseUrl', 'http://serverB');
+        expect(requestStub.args[2][0]).to.have.property('baseUrl', 'http://serverC');
+        done();
+      });
+    });
   });