Merge pull request #62 from tharropoulos/fix/null-node-access-ts

Fix Node health checks referencing a null pointer

Author: kishorenc

src/main/java/org/typesense/api/ApiCall.java

@@ -61,7 +61,7 @@ boolean isDueForHealthCheck(Node node) {
     // Loops in a round-robin fashion to check for a healthy node and returns it
     Node getNode() {
         if (configuration.nearestNode != null) {
-            if (isDueForHealthCheck((configuration.nearestNode)) || configuration.nearestNode.isHealthy) {
+            if (configuration.nearestNode.isHealthy || isDueForHealthCheck((configuration.nearestNode)) ) {
                 return configuration.nearestNode;
             }
         }

src/main/java/org/typesense/resources/Node.java

@@ -25,6 +25,7 @@ public Node(String protocol, String host, String port) {
         this.host = host;
         this.port = port;
         this.isHealthy = true;
+        this.lastAccessTimestamp = LocalDateTime.now();
 
         if (protocol == null) {
             throw new RuntimeException("Protocol cannot be null");

src/test/java/org/typesense/api/APICallTest.java

@@ -14,23 +14,33 @@
 class APICallTest {
 
     private ApiCall apiCall;
+    private Node nearestNode;
 
-    @BeforeEach
-    void setUp() throws Exception {
+    void setUpNoNearestNode() throws Exception {
         List<Node> nodes = new ArrayList<>();
         nodes.add(new Node("http","localhost","8108"));
         nodes.add(new Node("http","localhost","7108"));
         nodes.add(new Node("http","localhost","6108"));
         apiCall = new ApiCall(new Configuration(nodes, Duration.ofSeconds(3),"xyz"));
     }
 
+    void setUpNearestNode() throws Exception {
+        List<Node> nodes = new ArrayList<>();
+        nodes.add(new Node("http","localhost","8108"));
+        nodes.add(new Node("http","localhost","7108"));
+        nodes.add(new Node("http","localhost","6108"));
+        nearestNode = new Node("http","localhost","0000");
+        apiCall = new ApiCall(new Configuration(nearestNode, nodes, Duration.ofSeconds(3),"xyz"));
+    }
+
     @AfterEach
     void tearDown() throws Exception {
 
     }
 
     @Test
     void testRoundRobin() throws Exception {
+        setUpNoNearestNode();
         assertEquals("7108", apiCall.getNode().port);
         assertEquals("6108", apiCall.getNode().port);
         assertEquals("8108", apiCall.getNode().port);
@@ -39,4 +49,28 @@ void testRoundRobin() throws Exception {
         assertEquals("6108", apiCall.getNode().port);
         assertEquals("8108", apiCall.getNode().port);
     }
+
+
+    @Test
+    void testUnhealthyNearestNode() throws Exception {
+        setUpNearestNode();
+        nearestNode.isHealthy = false;
+        assertEquals("7108", apiCall.getNode().port);
+    }
+
+    @Test
+    void testHealthyNearestNode() throws Exception {
+        setUpNearestNode();
+        assertEquals("0000", apiCall.getNode().port);
+    }
+
+    @Test
+    void testUnhealthyNearestNodeDueForHealthCheck() throws Exception {
+        setUpNearestNode();
+        nearestNode.isHealthy = false;
+        nearestNode.lastAccessTimestamp = nearestNode.lastAccessTimestamp.minusSeconds(63);
+        assertEquals("0000", apiCall.getNode().port);
+    }
+
+
 }