Merge pull request #38 from tadamski/WEJBHTTP-34-api-master

[WEJBHTTP-34] Updates to EJB over HTTP discovery

ejb/src/main/java/org/wildfly/httpclient/ejb/HttpEJBDiscoveryProvider.java

@@ -38,6 +38,7 @@
 import org.wildfly.security.auth.client.AuthenticationConfiguration;
 import org.wildfly.security.auth.client.AuthenticationContext;
 import org.wildfly.security.auth.client.AuthenticationContextConfigurationClient;
+import org.wildfly.security.manager.WildFlySecurityManager;
 import org.xnio.IoUtils;
 
 import javax.net.ssl.SSLContext;
@@ -47,6 +48,7 @@
 import java.util.List;
 import java.util.Set;
 import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.stream.Collectors;
 
@@ -64,24 +66,35 @@ public final class HttpEJBDiscoveryProvider implements DiscoveryProvider {
 
     private static final AuthenticationContextConfigurationClient AUTH_CONFIGURATION_CLIENT = doPrivileged(AuthenticationContextConfigurationClient.ACTION);
 
+    private static final long CACHE_REFRESH_TIMEOUT = TimeUnit.MILLISECONDS.toNanos(Long.parseLong(
+            WildFlySecurityManager.getPropertyPrivileged("org.wildfly.httpclient.ejb.discovery.cache-refresh-timeout", "300000")));
+
     private Set<ServiceURL> serviceURLCache = new HashSet<>();
-    private AtomicBoolean shouldRefreshCache = new AtomicBoolean(true);
+    private AtomicBoolean cacheInvalid = new AtomicBoolean(true);
+    private long cacheRefreshTimestamp = 0L;
 
     HttpEJBDiscoveryProvider() {
     }
 
     public DiscoveryRequest discover(final ServiceType serviceType, final FilterSpec filterSpec, final DiscoveryResult discoveryResult) {
         final EJBClientContext ejbClientContext = getCurrent();
 
-        if (shouldRefreshCache.get()) {
+        if (shouldRefreshCache()) {
             refreshCache(ejbClientContext);
         }
 
-        searchCache(discoveryResult, filterSpec);
+        searchCache(discoveryResult, filterSpec, ejbClientContext);
 
         return DiscoveryRequest.NULL;
     }
 
+    private boolean shouldRefreshCache() {
+        if (cacheInvalid.get() || ((System.nanoTime() - cacheRefreshTimestamp) > CACHE_REFRESH_TIMEOUT)) {
+            return true;
+        }
+        return false;
+    }
+
     private boolean supportsScheme(String s) {
         switch (s) {
             case "http":
@@ -91,13 +104,23 @@ private boolean supportsScheme(String s) {
         return false;
     }
 
-    private void searchCache(final DiscoveryResult discoveryResult, final FilterSpec filterSpec) {
+    private void searchCache(final DiscoveryResult discoveryResult, final FilterSpec filterSpec, final EJBClientContext ejbClientContext) {
+        final boolean resultsPresent = doSearchCache(discoveryResult, filterSpec);
+        if(!resultsPresent){
+            refreshCache(ejbClientContext);
+        }
+        discoveryResult.complete();
+    }
+
+    private boolean doSearchCache(final DiscoveryResult discoveryResult, final FilterSpec filterSpec) {
+        boolean resultsPresent = false;
         for (ServiceURL serviceURL : serviceURLCache) {
             if (serviceURL.satisfies(filterSpec)) {
                 discoveryResult.addMatch(serviceURL.getLocationURI());
+                resultsPresent = true;
             }
         }
-        discoveryResult.complete();
+        return resultsPresent;
     }
 
     private void refreshCache(final EJBClientContext ejbClientContext){
@@ -111,11 +134,12 @@ private void refreshCache(final EJBClientContext ejbClientContext){
         }
         try {
             outstandingLatch.await();
-            shouldRefreshCache.set(false);
+            cacheInvalid.set(false);
+            cacheRefreshTimestamp = System.nanoTime();
         } catch(InterruptedException e){
             EjbHttpClientMessages.MESSAGES.httpDiscoveryInterrupted(e);
         }
-        shouldRefreshCache.set(false);
+        cacheInvalid.set(false);
     }
 
     private void disoverFromConnection(final EJBClientConnection connection, final CountDownLatch outstandingLatch) {
@@ -201,7 +225,7 @@ private ServiceURL createServiceURL(final URI newUri, final EJBModuleIdentifier
 
     @Override
     public void processMissingTarget(URI location, Exception cause) {
-        shouldRefreshCache.set(true);
+        cacheInvalid.set(true);
     }
 }