push queue breaking change (#530)

don't run test against server version after v2.3.4
building version comparisons into ServerInfo
added notes about version change

README.md

@@ -24,6 +24,17 @@ Version 2.5.0 adds some back pressure to publish calls to alleviate issues when
 
 Previous versions are still available in the repo.
 
+### Versions 2.11.6 and server versions
+
+Version 2.11.6 is the last java-nats version which is supported to work with server v2.3.4 and earlier.
+It will not be officially supported to work with servers after v2.3.4, but _should be fine_ if you don't use
+the queue behavior advertised in example code `NatsJsPushSubQueueDurable.java` and provided with java-nats 2.11.5. 
+The example does not work correctly against server versions after server v2.3.4 
+due to a significant change made to correct _queue_ behavior that was considered wrong.
+
+If you want to take advantage of the fixes and features provided in the server after v2.3.4, 
+you __must__ upgrade to the upcoming client release, version 2.12.0
+
 ### SSL/TLS Performance
 
 After recent tests we realized that TLS performance is lower than we would like. After researching the problem and possible solutions we came to a few conclusions:

src/main/java/io/nats/client/api/ServerInfo.java

@@ -137,6 +137,30 @@ public String getCluster() {
         return cluster;
     }
 
+    private String getComparableVersion(String vString) {
+        try {
+            String[] v = vString.replaceAll("v", "").replaceAll("-", ".").split("\\Q.\\E");
+            int at = vString.indexOf("-");
+            return "" + (Integer.parseInt(v[0]) * 10000) + (Integer.parseInt(v[1]) * 100) + Integer.parseInt(v[2])
+                    + (at == -1 ? "" : vString.substring(at));
+        }
+        catch (NumberFormatException nfe) {
+            return "";
+        }
+    }
+
+    public boolean isNewerVersionThan(String vTarget) {
+        return getComparableVersion(version).compareTo(getComparableVersion(vTarget)) > 0;
+    }
+
+    public boolean isSameVersion(String vTarget) {
+        return getComparableVersion(version).compareTo(getComparableVersion(vTarget)) == 0;
+    }
+
+    public boolean isOlderThanVersion(String vTarget) {
+        return getComparableVersion(version).compareTo(getComparableVersion(vTarget)) < 0;
+    }
+
     @Override
     public String toString() {
         return "ServerInfo{" +

src/test/java/io/nats/client/api/ServerInfoTests.java

@@ -33,7 +33,7 @@ public void testValidInfoString() {
         ServerInfo info = new ServerInfo(json);
         assertEquals("serverId", info.getServerId());
         assertEquals("serverName", info.getServerName());
-        assertEquals("0.0.0", info.getVersion());
+        assertEquals("1.2.3", info.getVersion());
         assertEquals("go0.0.0", info.getGoVersion());
         assertEquals("host", info.getHost());
         assertEquals(7777, info.getPort());
@@ -53,6 +53,22 @@ public void testValidInfoString() {
         assertArrayEquals(ascii, info.getNonce());
 
         assertNotNull(info.toString()); // COVERAGE
+
+        ServerInfo info234 = new ServerInfo(json.replace("1.2.3", "2.3.4"));
+        ServerInfo info235 = new ServerInfo(json.replace("1.2.3", "2.3.5"));
+        ServerInfo info235Beta2 = new ServerInfo(json.replace("1.2.3", "2.3.5-beta.2"));
+        assertTrue(info.isOlderThanVersion("2.3.4"));
+        assertTrue(info234.isOlderThanVersion("2.3.5"));
+        assertTrue(info235.isOlderThanVersion("2.3.5-beta.2"));
+        assertTrue(info.isSameVersion("1.2.3"));
+        assertTrue(info234.isSameVersion("2.3.4"));
+        assertTrue(info235.isSameVersion("2.3.5"));
+        assertTrue(info235Beta2.isSameVersion("2.3.5-beta.2"));
+        assertFalse(info235.isSameVersion("2.3.4"));
+        assertFalse(info235Beta2.isSameVersion("2.3.5"));
+        assertTrue(info234.isNewerVersionThan("1.2.3"));
+        assertTrue(info235.isNewerVersionThan("2.3.4"));
+        assertTrue(info235Beta2.isNewerVersionThan("2.3.5"));
     }
 
     @Test

src/test/java/io/nats/client/impl/JetStreamPushQueueTests.java

@@ -31,6 +31,11 @@ public class JetStreamPushQueueTests extends JetStreamTestBase {
     @Test
     public void testQueueSub() throws Exception {
         runInJsServer(nc -> {
+            if (nc.getServerInfo().isNewerVersionThan("2.3.4")) {
+                System.out.println("This test will not work after server version v2.3.4");
+                return;
+            }
+
             // Create our JetStream context to receive JetStream messages.
             JetStream js = nc.jetStream();
 

src/test/resources/data/ServerInfoJson.txt

@@ -1 +1 @@
-INFO {"server_id": "serverId","server_name": "serverName","version": "0.0.0","go": "go0.0.0","host": "host","port": 7777,"headersSupported": true,"auth_required": true,"tls_required": true,"max_payload": 100000000000,"proto": 1,"ldm": true,"jetstream": true,"client_id": 42,"client_ip": "127.0.0.1","cluster": "cluster","connect_urls":["url0", "url1"],"nonce":"<encoded>","headers": true,}
+INFO {"server_id": "serverId","server_name": "serverName","version": "1.2.3","go": "go0.0.0","host": "host","port": 7777,"headersSupported": true,"auth_required": true,"tls_required": true,"max_payload": 100000000000,"proto": 1,"ldm": true,"jetstream": true,"client_id": 42,"client_ip": "127.0.0.1","cluster": "cluster","connect_urls":["url0", "url1"],"nonce":"<encoded>","headers": true,}