Rule based segment client engine

client/src/main/java/io/split/Spec.java

@@ -6,6 +6,8 @@ private Spec() {
         // restrict instantiation
     }
 
-    public static final String SPEC_VERSION = "1.1";
+    public static String SPEC_VERSION = "1.3";
+    public static final String SPEC_1_3 = "1.3";
+    public static final String SPEC_1_1 = "1.1";
 }
 

client/src/main/java/io/split/client/HttpSplitChangeFetcher.java

@@ -2,6 +2,7 @@
 
 import com.google.common.annotations.VisibleForTesting;
 
+import io.split.Spec;
 import io.split.client.dtos.SplitChange;
 import io.split.client.dtos.SplitHttpResponse;
 import io.split.client.exceptions.UriTooLongException;
@@ -31,6 +32,7 @@ public final class HttpSplitChangeFetcher implements SplitChangeFetcher {
     private static final Logger _log = LoggerFactory.getLogger(HttpSplitChangeFetcher.class);
 
     private static final String SINCE = "since";
+    private static final String RB_SINCE = "rbSince";
     private static final String TILL = "till";
     private static final String SETS = "sets";
     private static final String SPEC = "s";
@@ -56,38 +58,48 @@ long makeRandomTill() {
     }
 
     @Override
-    public SplitChange fetch(long since, FetchOptions options) {
+    public SplitChange fetch(long since, long sinceRBS, FetchOptions options) {
 
         long start = System.currentTimeMillis();
+        for (int i=0; i<2; i++) {
+            try {
+                URIBuilder uriBuilder = new URIBuilder(_target).addParameter(SPEC, "" + SPEC_VERSION);
+                uriBuilder.addParameter(SINCE, "" + since);
+                if (SPEC_VERSION.equals(Spec.SPEC_1_3)) {
+                    uriBuilder.addParameter(RB_SINCE, "" + sinceRBS);
+                }
+                if (!options.flagSetsFilter().isEmpty()) {
+                    uriBuilder.addParameter(SETS, "" + options.flagSetsFilter());
+                }
+                if (options.hasCustomCN()) {
+                    uriBuilder.addParameter(TILL, "" + options.targetCN());
+                }
+                URI uri = uriBuilder.build();
+                SplitHttpResponse response = _client.get(uri, options, null);
 
-        try {
-            URIBuilder uriBuilder = new URIBuilder(_target).addParameter(SPEC, "" + SPEC_VERSION);
-            uriBuilder.addParameter(SINCE, "" + since);
-            if (!options.flagSetsFilter().isEmpty()) {
-                uriBuilder.addParameter(SETS, "" + options.flagSetsFilter());
-            }
-            if (options.hasCustomCN()) {
-                uriBuilder.addParameter(TILL, "" + options.targetCN());
-            }
-            URI uri = uriBuilder.build();
-            SplitHttpResponse response = _client.get(uri, options, null);
-
-            if (response.statusCode() < HttpStatus.SC_OK || response.statusCode() >= HttpStatus.SC_MULTIPLE_CHOICES) {
-                if (response.statusCode() == HttpStatus.SC_REQUEST_URI_TOO_LONG) {
-                    _log.error("The amount of flag sets provided are big causing uri length error.");
-                    throw new UriTooLongException(String.format("Status code: %s. Message: %s", response.statusCode(), response.statusMessage()));
+                if (response.statusCode() < HttpStatus.SC_OK || response.statusCode() >= HttpStatus.SC_MULTIPLE_CHOICES) {
+                    if (response.statusCode() == HttpStatus.SC_REQUEST_URI_TOO_LONG) {
+                        _log.error("The amount of flag sets provided are big causing uri length error.");
+                        throw new UriTooLongException(String.format("Status code: %s. Message: %s", response.statusCode(), response.statusMessage()));
+                    }
+                    if (response.statusCode() == HttpStatus.SC_BAD_REQUEST && response.statusMessage().equals("unknown spec")) {
+                        _log.warn(String.format("Detected old spec response, falling back to spec 1.1"));
+                        SPEC_VERSION = Spec.SPEC_1_1;
+                        continue;
+                    }
+                    _telemetryRuntimeProducer.recordSyncError(ResourceEnum.SPLIT_SYNC, response.statusCode());
+                    throw new IllegalStateException(
+                            String.format("Could not retrieve splitChanges since %s; http return code %s", since, response.statusCode())
+                    );
                 }
-                _telemetryRuntimeProducer.recordSyncError(ResourceEnum.SPLIT_SYNC, response.statusCode());
-                throw new IllegalStateException(
-                        String.format("Could not retrieve splitChanges since %s; http return code %s", since, response.statusCode())
-                );
+                return Json.fromJson(response.body(), SplitChange.class);
+            } catch (Exception e) {
+                throw new IllegalStateException(String.format("Problem fetching splitChanges since %s: %s", since, e), e);
+            } finally {
+                _telemetryRuntimeProducer.recordSyncLatency(HTTPLatenciesEnum.SPLITS, System.currentTimeMillis() - start);
             }
-            return Json.fromJson(response.body(), SplitChange.class);
-        } catch (Exception e) {
-            throw new IllegalStateException(String.format("Problem fetching splitChanges since %s: %s", since, e), e);
-        } finally {
-            _telemetryRuntimeProducer.recordSyncLatency(HTTPLatenciesEnum.SPLITS, System.currentTimeMillis()-start);
         }
+        return null;
     }
 
     @VisibleForTesting

client/src/main/java/io/split/client/JsonLocalhostSplitChangeFetcher.java

@@ -29,7 +29,7 @@ public JsonLocalhostSplitChangeFetcher(InputStreamProvider inputStreamProvider)
     }
 
     @Override
-    public SplitChange fetch(long since, FetchOptions options) {
+    public SplitChange fetch(long since, long RBsince,  FetchOptions options) {
         try {
             JsonReader jsonReader = new JsonReader(new BufferedReader(new InputStreamReader(_inputStreamProvider.get(), StandardCharsets.UTF_8)));
             SplitChange splitChange = Json.fromJson(jsonReader, SplitChange.class);

client/src/main/java/io/split/client/LegacyLocalhostSplitChangeFetcher.java

@@ -34,7 +34,7 @@ public LegacyLocalhostSplitChangeFetcher(String directory) {
     }
 
     @Override
-    public SplitChange fetch(long since, FetchOptions options) {
+    public SplitChange fetch(long since, long sinceRBS, FetchOptions options) {
 
         try (BufferedReader reader = new BufferedReader(new FileReader(_splitFile))) {
             SplitChange splitChange = new SplitChange();