Added tests for response merging process

lib/member.js

@@ -19,8 +19,10 @@
 // THE SOFTWARE.
 'use strict';
 
-function Member() {
-
+function Member(address, status, incarnationNumber) {
+    this.address = address;
+    this.status = status;
+    this.incarnationNumber = incarnationNumber;
 }
 
 Member.Status = {

test/join-response-merge-test.js

@@ -0,0 +1,122 @@
+// Copyright (c) 2015 Uber Technologies, Inc.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+'use strict';
+
+var Member = require('../lib/member.js');
+var mergeJoinResponses = require('../lib/swim/join-response-merge.js');
+var test = require('tape');
+
+test('no responses results in empty array', function t(assert) {
+    var result = mergeJoinResponses(null);
+    assert.deepEqual(result, [], 'empty array');
+
+    result = mergeJoinResponses([]);
+    assert.deepEqual(result, [], 'empty array');
+
+    assert.end();
+});
+
+test('responses with same checksum uses first response', function t(assert) {
+    var responseCounter = 0;
+    var firstResponse = createResponse();
+    var responses = [
+        firstResponse,
+        createResponse(),
+        createResponse()
+    ];
+
+    var result = mergeJoinResponses(responses);
+    assert.deepEqual(result, firstResponse.members, 'takes first response');
+
+    assert.end();
+
+    function createResponse() {
+        return {
+            checksum: 123456789,
+            members: [{
+                address: '127.0.0.1:' + (3000 + (responseCounter++)),
+                status: 'alive',
+                incarnationNumber: Date.now()
+            }]
+        };
+    }
+});
+
+test('merges responses and takes those updates with higher incarnation numbers', function t(assert) {
+    var firstResponse = createResponse(123456789, [
+        new Member('127.0.0.1:3000', 'suspect', 1),
+        new Member('127.0.0.1:3001', 'alive', 2)
+    ]);
+    var secondResponse = createResponse(23456789, [
+        new Member('127.0.0.1:3000', 'alive', 2),
+        new Member('127.0.0.1:3001', 'suspect', 1),
+        new Member('127.0.0.1:3002', 'faulty', 1)
+    ]);
+    var mergedMembers = [
+        new Member('127.0.0.1:3000', 'alive', 2),
+        new Member('127.0.0.1:3001', 'alive', 2),
+        new Member('127.0.0.1:3002', 'faulty', 1),
+    ];
+
+    var result = mergeJoinResponses([firstResponse, secondResponse]);
+    assert.deepEqual(result, mergedMembers, 'members are merged');
+
+    assert.end();
+
+    function createResponse(checksum, members) {
+        return {
+            checksum: checksum,
+            members: members
+        };
+    }
+});
+
+test('merges responses when checksums are null', function t(assert) {
+    var firstResponse = createResponse(null, [
+        new Member('127.0.0.1:3000', 'suspect', 1),
+        new Member('127.0.0.1:3001', 'alive', 2)
+    ]);
+    var secondResponse = createResponse(null, [
+        new Member('127.0.0.1:3000', 'alive', 2),
+        new Member('127.0.0.1:3001', 'suspect', 1),
+        new Member('127.0.0.1:3002', 'faulty', 1)
+    ]);
+    var mergedMembers = [
+        new Member('127.0.0.1:3000', 'alive', 2),
+        new Member('127.0.0.1:3001', 'alive', 2),
+        new Member('127.0.0.1:3002', 'faulty', 1)
+    ];
+
+    var result = mergeJoinResponses([firstResponse, secondResponse]);
+    assert.deepEqual(result, mergedMembers, 'members are merged');
+
+    firstResponse.checksum = 123456789;
+    result = mergeJoinResponses([firstResponse, secondResponse]);
+    assert.deepEqual(result, mergedMembers, 'members are merged');
+
+    assert.end();
+
+    function createResponse(checksum, members) {
+        return {
+            checksum: checksum,
+            members: members
+        };
+    }
+});