KNOX-2619 - HA dispatch should failover regardless of noFallback config until session is established (#456)
diff --git a/gateway-provider-ha/src/main/java/org/apache/knox/gateway/ha/dispatch/ConfigurableHADispatch.java b/gateway-provider-ha/src/main/java/org/apache/knox/gateway/ha/dispatch/ConfigurableHADispatch.java
index a7849a3..471161e 100644
--- a/gateway-provider-ha/src/main/java/org/apache/knox/gateway/ha/dispatch/ConfigurableHADispatch.java
+++ b/gateway-provider-ha/src/main/java/org/apache/knox/gateway/ha/dispatch/ConfigurableHADispatch.java
@@ -223,8 +223,17 @@
}
protected void failoverRequest(HttpUriRequest outboundRequest, HttpServletRequest inboundRequest, HttpServletResponse outboundResponse, HttpResponse inboundResponse, Exception exception) throws IOException {
- /* check for a case where no fallback is configured */
- if(stickySessionsEnabled && noFallbackEnabled) {
+ // Check whether the session cookie is present
+ Optional<Cookie> sessionCookie = Optional.empty();
+ if (inboundRequest.getCookies() != null) {
+ sessionCookie =
+ Arrays.stream(inboundRequest.getCookies())
+ .findFirst()
+ .filter(cookie -> stickySessionCookieName.equals(cookie.getName()));
+ }
+
+ // Check for a case where no fallback is configured
+ if(stickySessionsEnabled && noFallbackEnabled && sessionCookie.isPresent()) {
LOG.noFallbackError();
outboundResponse.sendError(HttpServletResponse.SC_BAD_GATEWAY, "Service connection error, HA failover disabled");
return;
diff --git a/gateway-provider-ha/src/test/java/org/apache/knox/gateway/ha/dispatch/DefaultHaDispatchTest.java b/gateway-provider-ha/src/test/java/org/apache/knox/gateway/ha/dispatch/DefaultHaDispatchTest.java
index 2584957..f3bf953 100644
--- a/gateway-provider-ha/src/test/java/org/apache/knox/gateway/ha/dispatch/DefaultHaDispatchTest.java
+++ b/gateway-provider-ha/src/test/java/org/apache/knox/gateway/ha/dispatch/DefaultHaDispatchTest.java
@@ -30,12 +30,15 @@
import org.apache.knox.gateway.ha.provider.HaServletContextListener;
import org.apache.knox.gateway.ha.provider.impl.DefaultHaProvider;
import org.apache.knox.gateway.ha.provider.impl.HaDescriptorFactory;
+import org.apache.knox.gateway.ha.provider.impl.HaServiceConfigConstants;
import org.apache.knox.gateway.servlet.SynchronousServletOutputStreamAdapter;
import org.apache.http.client.methods.HttpRequestBase;
import org.apache.http.client.methods.HttpUriRequest;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClientBuilder;
import org.apache.http.params.BasicHttpParams;
+import org.easymock.Capture;
+import org.easymock.CaptureType;
import org.easymock.EasyMock;
import org.easymock.IAnswer;
import org.junit.Assert;
@@ -53,6 +56,8 @@
import java.util.ArrayList;
import java.util.concurrent.atomic.AtomicInteger;
+import static org.easymock.EasyMock.anyString;
+
public class DefaultHaDispatchTest {
@Test
@@ -540,11 +545,173 @@
}
/**
- * Test the case where sticky session is on (and loadbalancing is on)
- * Expected behavior: When
- * @throws Exception
+ * Test the case where loadbalancing is on, sticky sessions is on, fallback is disabled, and the initial request
+ * fails.
+ *
+ * Expected behavior: Failover should occur until the initial session has been established, regardless of the
+ * noFallback setting.
+ *
+ * KNOX-2619
*/
@Test
+ public void testFailoverStickyOnFallbackOff() throws Exception {
+ doTestFailoverStickyOnFallbackOff(false);
+ }
+
+ /**
+ * Test the case where loadbalancing is on, sticky sessions is on, fallback is disabled, and the initial request
+ * fails.
+ *
+ * Expected behavior: Failover should occur until the initial session has been established, regardless of the
+ * noFallback setting.
+ *
+ * KNOX-2619
+ */
+ @Test
+ public void testFailoverStickyOnFallbackOff_SessionEstablished() throws Exception {
+ doTestFailoverStickyOnFallbackOff(true);
+ }
+
+ private void doTestFailoverStickyOnFallbackOff(final Boolean withCookie)
+ throws Exception {
+ final String enableLoadBalancing = "true"; // load-balancing is required for sticky sessions to be enabled
+ final String enableStickySession = "true";
+ final String noFallback = "true";
+
+ final String serviceName = "OOZIE";
+
+ HaDescriptor descriptor = HaDescriptorFactory.createDescriptor();
+ descriptor.addServiceConfig(HaDescriptorFactory.createServiceConfig(serviceName,
+ "true",
+ "1",
+ "1000",
+ null,
+ null,
+ enableLoadBalancing,
+ enableStickySession,
+ null,
+ noFallback));
+ final HaProvider provider = new DefaultHaProvider(descriptor);
+ final URI uri1 = new URI( "http://host1.valid" );
+ final URI uri2 = new URI( "http://host2.valid" );
+ final ArrayList<String> urlList = new ArrayList<>();
+ urlList.add(uri1.toString());
+ urlList.add(uri2.toString());
+ provider.addHaService(serviceName, urlList);
+ FilterConfig filterConfig = EasyMock.createNiceMock(FilterConfig.class);
+ ServletContext servletContext = EasyMock.createNiceMock(ServletContext.class);
+
+ EasyMock.expect(filterConfig.getServletContext()).andReturn(servletContext).anyTimes();
+ EasyMock.expect(servletContext.getAttribute(HaServletContextListener.PROVIDER_ATTRIBUTE_NAME)).andReturn(provider).anyTimes();
+
+ BasicHttpParams params = new BasicHttpParams();
+
+ HttpUriRequest outboundRequest = EasyMock.createNiceMock(HttpRequestBase.class);
+ EasyMock.expect(outboundRequest.getMethod()).andReturn( "GET" ).anyTimes();
+ EasyMock.expect(outboundRequest.getURI()).andReturn( uri1 ).anyTimes();
+ EasyMock.expect(outboundRequest.getParams()).andReturn( params ).anyTimes();
+ // Capture the last request URI to be set on the request
+ Capture<URI> requestURICapture = EasyMock.newCapture(CaptureType.LAST);
+ ((HttpRequestBase) outboundRequest).setURI(EasyMock.capture(requestURICapture));
+ EasyMock.expectLastCall().anyTimes();
+
+ /* backend request */
+ HttpServletRequest inboundRequest = EasyMock.createNiceMock(HttpServletRequest.class);
+ EasyMock.expect(inboundRequest.getRequestURL()).andReturn( new StringBuffer(uri2.toString()) ).once();
+ EasyMock.expect(inboundRequest.getAttribute("dispatch.ha.failover.counter")).andReturn(new AtomicInteger(0)).once();
+ EasyMock.expect(inboundRequest.getAttribute("dispatch.ha.failover.counter")).andReturn(new AtomicInteger(1)).once();
+ if (withCookie) {
+ inboundRequest.getCookies();
+ EasyMock.expectLastCall()
+ .andReturn(new Cookie[] { new Cookie(HaServiceConfigConstants.DEFAULT_STICKY_SESSION_COOKIE_NAME + "-" + serviceName,
+ "59973e253ae20de796c6ef413608ec1c80fca24310a4cbdecc0ff97aeea55745") })
+ .anyTimes();
+ } else {
+ EasyMock.expect(inboundRequest.getCookies()).andReturn(null).anyTimes();
+ }
+
+ /* backend response */
+ CloseableHttpResponse inboundResponse = EasyMock.createNiceMock(CloseableHttpResponse.class);
+ final StatusLine statusLine = EasyMock.createNiceMock(StatusLine.class);
+ final HttpEntity entity = EasyMock.createNiceMock(HttpEntity.class);
+ final Header header = EasyMock.createNiceMock(Header.class);
+ final ServletContext context = EasyMock.createNiceMock(ServletContext.class);
+ final GatewayConfig config = EasyMock.createNiceMock(GatewayConfig.class);
+ final ByteArrayInputStream backendResponse = new ByteArrayInputStream("knox-backend".getBytes(StandardCharsets.UTF_8));
+
+ EasyMock.expect(inboundResponse.getStatusLine()).andReturn(statusLine).anyTimes();
+ EasyMock.expect(statusLine.getStatusCode()).andReturn(HttpStatus.SC_OK).anyTimes();
+ EasyMock.expect(inboundResponse.getEntity()).andReturn(entity).anyTimes();
+ EasyMock.expect(inboundResponse.getAllHeaders()).andReturn(new Header[0]).anyTimes();
+ EasyMock.expect(inboundRequest.getServletContext()).andReturn(context).anyTimes();
+ EasyMock.expect(entity.getContent()).andReturn(backendResponse).anyTimes();
+ EasyMock.expect(entity.getContentType()).andReturn(header).anyTimes();
+ EasyMock.expect(header.getElements()).andReturn(new HeaderElement[]{}).anyTimes();
+ EasyMock.expect(entity.getContentLength()).andReturn(4L).anyTimes();
+ EasyMock.expect(context.getAttribute(GatewayConfig.GATEWAY_CONFIG_ATTRIBUTE)).andReturn(config).anyTimes();
+
+ HttpServletResponse outboundResponse = EasyMock.createNiceMock(HttpServletResponse.class);
+ // Capture the status code when it is set on the response
+ Capture<Integer> statusCodeCapture = EasyMock.newCapture(CaptureType.FIRST);
+ if (withCookie) {
+ outboundResponse.sendError(EasyMock.captureInt(statusCodeCapture), anyString());
+ } else {
+ outboundResponse.setStatus(EasyMock.captureInt(statusCodeCapture));
+ }
+ EasyMock.expectLastCall().once();
+ EasyMock.expect(outboundResponse.getOutputStream())
+ .andAnswer((IAnswer<SynchronousServletOutputStreamAdapter>) () -> new SynchronousServletOutputStreamAdapter() {
+ @Override
+ public void write( int b ) throws IOException {
+ throw new IOException( "unreachable-host" ); // Fail-over condition
+ }
+ }).once();
+
+ CloseableHttpClient mockHttpClient = EasyMock.createNiceMock(CloseableHttpClient.class);
+ EasyMock.expect(mockHttpClient.execute(outboundRequest)).andReturn(inboundResponse).anyTimes();
+
+ EasyMock.replay(filterConfig,
+ servletContext,
+ outboundRequest,
+ inboundRequest,
+ outboundResponse,
+ mockHttpClient,
+ inboundResponse,
+ statusLine,
+ entity,
+ header,
+ context,
+ config);
+
+ Assert.assertEquals(uri1.toString(), provider.getActiveURL(serviceName));
+ ConfigurableHADispatch dispatch = new ConfigurableHADispatch();
+ dispatch.setHttpClient(mockHttpClient);
+ dispatch.setHaProvider(provider);
+ dispatch.setServiceRole(serviceName);
+ dispatch.init();
+ try {
+ dispatch.executeRequestWrapper(outboundRequest, inboundRequest, outboundResponse);
+ } catch (IOException e) {
+ //this is expected after the failover limit is reached
+ }
+
+ if (withCookie) {
+ Assert.assertEquals("Expected no fail-over because the initial request contained a session cookie.",
+ HttpStatus.SC_BAD_GATEWAY,
+ statusCodeCapture.getValue().intValue());
+ } else {
+ // The request should have failed over
+ Assert.assertEquals("Expected the request to have failed-over to the alternate host.", uri2, requestURICapture.getValue());
+ Assert.assertEquals("Expected the failed-over request to succeed.", HttpStatus.SC_OK, statusCodeCapture.getValue().intValue());
+ }
+ }
+
+ /**
+ * Test the case where sticky session is on (and loadbalancing is on)
+ * Expected behavior: When
+ * @throws Exception
+ */
+ @Test
public void testStickyOn() throws Exception {
String serviceName = "OOZIE";
HaDescriptor descriptor = HaDescriptorFactory.createDescriptor();
