fix: flagd caching

providers/flagd/src/main/java/dev/openfeature/contrib/providers/flagd/Config.java

@@ -1,5 +1,7 @@
 package dev.openfeature.contrib.providers.flagd;
 
+import dev.openfeature.contrib.providers.flagd.resolver.grpc.cache.CacheType;
+
 /**
  * Helper class to hold configuration default values.
  */
@@ -34,7 +36,7 @@ public final class Config {
     public static final String REASON_FIELD = "reason";
     public static final String METADATA_FIELD = "metadata";
 
-    public static final String LRU_CACHE = "lru";
+    public static final String LRU_CACHE = CacheType.LRU.getValue();
     static final String DEFAULT_CACHE = LRU_CACHE;
 
     static final int DEFAULT_MAX_EVENT_STREAM_RETRIES = 5;

providers/flagd/src/main/java/dev/openfeature/contrib/providers/flagd/FlagdProvider.java

@@ -2,7 +2,7 @@
 
 import dev.openfeature.contrib.providers.flagd.resolver.Resolver;
 import dev.openfeature.contrib.providers.flagd.resolver.grpc.GrpcResolver;
-import dev.openfeature.contrib.providers.flagd.resolver.grpc.cache.CacheFactory;
+import dev.openfeature.contrib.providers.flagd.resolver.grpc.cache.Cache;
 import dev.openfeature.contrib.providers.flagd.resolver.process.InProcessResolver;
 import dev.openfeature.sdk.EvaluationContext;
 import dev.openfeature.sdk.EventProvider;
@@ -51,7 +51,10 @@ public FlagdProvider(final FlagdOptions options) {
                 break;
             case RPC:
                 this.flagResolver =
-                        new GrpcResolver(options, CacheFactory.getCache(options), this::getState, this::setState);
+                        new GrpcResolver(options,
+                                new Cache(options.getCacheType(), options.getMaxCacheSize()),
+                                this::getState,
+                                this::setState);
                 break;
             default:
                 throw new IllegalStateException(

providers/flagd/src/main/java/dev/openfeature/contrib/providers/flagd/resolver/grpc/cache/Cache.java

@@ -1,41 +1,42 @@
 package dev.openfeature.contrib.providers.flagd.resolver.grpc.cache;
 
 import dev.openfeature.sdk.ProviderEvaluation;
+import lombok.Getter;
+import lombok.extern.slf4j.Slf4j;
 import org.apache.commons.collections4.map.LRUMap;
 
 import java.util.Collections;
 import java.util.Map;
 
+import static dev.openfeature.contrib.providers.flagd.resolver.grpc.cache.CacheType.DISABLED;
+import static dev.openfeature.contrib.providers.flagd.resolver.grpc.cache.CacheType.LRU;
+
 /**
  * Exposes caching mechanism for flag evaluations.
  */
+@Slf4j
 public class Cache {
-    private Map<String,ProviderEvaluation<? extends Object>> store;
-    private Boolean enabled = false;
+    private Map<String, ProviderEvaluation<? extends Object>> store;
+
+    @Getter
+    private final Boolean enabled;
 
     /**
      * Initialize the cache.
-     * @param type of cache.
+     *
+     * @param forType      type of the cache.
      * @param maxCacheSize max amount of element to keep.
      */
-    public Cache(CacheType type, int maxCacheSize) {
-        if (type == null) {
-            return;
-        }
-
-        switch (type) {
-            case DISABLED:
-                return;
-            case LRU:
-            default:
-                this.store = Collections.synchronizedMap(new LRUMap<>(maxCacheSize));
+    public Cache(final String forType, int maxCacheSize) {
+        if (DISABLED.getValue().equals(forType)) {
+            enabled = false;
+        } else if (LRU.getValue().equals(forType)) {
+            enabled = true;
+            this.store = Collections.synchronizedMap(new LRUMap<>(maxCacheSize));
+        } else {
+            enabled = false;
+            log.warn(String.format("Unsupported cache type %s, continuing without cache", forType));
         }
-
-        this.enabled = true;
-    }
-
-    public Boolean getEnabled() {
-        return this.enabled;
     }
 
     public void put(String key, ProviderEvaluation<? extends Object> value) {

providers/flagd/src/main/java/dev/openfeature/contrib/providers/flagd/resolver/grpc/cache/CacheType.java

@@ -1,22 +1,18 @@
 package dev.openfeature.contrib.providers.flagd.resolver.grpc.cache;
 
-import static dev.openfeature.contrib.providers.flagd.Config.LRU_CACHE;
+import lombok.Getter;
 
 /**
  * Defines which type of cache to use.
  */
+@Getter
 public enum CacheType {
     DISABLED("disabled"),
-    LRU(LRU_CACHE);
+    LRU("lru");
 
-    private final String type;
+    private final String value;
 
-    CacheType(String type) {
-        this.type = type;
-    }
-
-    @Override
-    public String toString() {
-        return this.type;
+    CacheType(String value) {
+        this.value = value;
     }
 }

providers/flagd/src/test/java/dev/openfeature/contrib/providers/flagd/FlagdProviderTest.java

@@ -482,7 +482,7 @@ void invalidate_cache() {
             mockStaticService.when(() -> ServiceGrpc.newStub(any()))
                     .thenReturn(serviceStubMock);
 
-            final Cache cache = new Cache(CacheType.LRU, 5);
+            final Cache cache = new Cache("lru", 5);
             grpc = new GrpcConnector(FlagdOptions.builder().build(), cache, state -> {
             });
         }
@@ -694,7 +694,7 @@ void disabled_cache() {
                 .resolveObject(argThat(x -> FLAG_KEY_OBJECT.equals(x.getFlagKey())))).thenReturn(objectResponse);
 
         // disabled cache
-        final Cache cache = new Cache(CacheType.DISABLED, 0);
+        final Cache cache = new Cache("disabled", 0);
 
         GrpcConnector grpc;
         try (MockedStatic<ServiceGrpc> mockStaticService = mockStatic(ServiceGrpc.class)) {
@@ -808,7 +808,7 @@ private FlagdProvider createProvider(GrpcConnector grpc) {
 
     // create provider with given grpc provider and state supplier
     private FlagdProvider createProvider(GrpcConnector grpc, Supplier<ProviderState> getState) {
-        final Cache cache = new Cache(CacheType.LRU, 5);
+        final Cache cache = new Cache("lru", 5);
 
         return createProvider(grpc, cache, getState);
     }

providers/flagd/src/test/java/dev/openfeature/contrib/providers/flagd/e2e/rpc/FlagdRpcSetup.java

@@ -1,5 +1,6 @@
 package dev.openfeature.contrib.providers.flagd.e2e.rpc;
 
+import dev.openfeature.contrib.providers.flagd.resolver.grpc.cache.CacheType;
 import org.junit.jupiter.api.Order;
 import org.junit.jupiter.api.parallel.Isolated;
 
@@ -19,10 +20,11 @@ public class FlagdRpcSetup {
     @BeforeAll()
     public static void setup() {
         FlagdRpcSetup.provider = new FlagdProvider(FlagdOptions.builder()
-        .resolverType(Config.Evaluator.RPC)
-        // set a generous deadline, to prevent timeouts in actions
-        .deadline(3000)
-        .build());
+                .resolverType(Config.Evaluator.RPC)
+                // set a generous deadline, to prevent timeouts in actions
+                .deadline(3000)
+                .cacheType(CacheType.DISABLED.getValue())
+                .build());
         StepDefinitions.setProvider(provider);
     }
 }

providers/flagd/src/test/java/dev/openfeature/contrib/providers/flagd/resolver/grpc/GrpcConnectorTest.java

@@ -51,7 +51,7 @@ void validate_retry_calls(int retries) throws NoSuchFieldException, IllegalAcces
                 .maxEventStreamRetries(retries)
                 .build();
 
-        final Cache cache = new Cache(CacheType.DISABLED, 0);
+        final Cache cache = new Cache("disabled", 0);
 
         final ServiceGrpc.ServiceStub mockStub = mock(ServiceGrpc.ServiceStub.class);
         doAnswer(invocation -> null).when(mockStub).eventStream(any(), any());
@@ -87,7 +87,7 @@ void validate_retry_calls(int retries) throws NoSuchFieldException, IllegalAcces
 
     @Test
     void initialization_succeed_with_connected_status() throws NoSuchFieldException, IllegalAccessException {
-        final Cache cache = new Cache(CacheType.DISABLED, 0);
+        final Cache cache = new Cache("disabled", 0);
 
         final ServiceGrpc.ServiceStub mockStub = mock(ServiceGrpc.ServiceStub.class);
         doAnswer(invocation -> null).when(mockStub).eventStream(any(), any());
@@ -111,7 +111,7 @@ void initialization_succeed_with_connected_status() throws NoSuchFieldException,
 
     @Test
     void initialization_fail_with_timeout() throws Exception {
-        final Cache cache = new Cache(CacheType.DISABLED, 0);
+        final Cache cache = new Cache("disabled", 0);
 
         final ServiceGrpc.ServiceStub mockStub = mock(ServiceGrpc.ServiceStub.class);
         doAnswer(invocation -> null).when(mockStub).eventStream(any(), any());

providers/flagd/src/test/java/dev/openfeature/contrib/providers/flagd/resolver/grpc/cache/CacheTest.java

@@ -0,0 +1,50 @@
+package dev.openfeature.contrib.providers.flagd.resolver.grpc.cache;
+
+import dev.openfeature.sdk.ProviderEvaluation;
+import org.junit.jupiter.api.Test;
+
+import static dev.openfeature.contrib.providers.flagd.resolver.grpc.cache.CacheType.DISABLED;
+import static dev.openfeature.contrib.providers.flagd.resolver.grpc.cache.CacheType.LRU;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+class CacheTest {
+
+    @Test
+    void cacheTypeTest() {
+        // given
+        final Cache disabled = new Cache(DISABLED.getValue(), 0);
+        final Cache lru = new Cache(LRU.getValue(), 10);
+        final Cache undefined = new Cache("invalid", 10);
+
+        // then
+        assertTrue(lru.getEnabled());
+        assertFalse(disabled.getEnabled());
+        assertFalse(undefined.getEnabled());
+    }
+
+
+    @Test
+    void lruOperationValidation() {
+        // given
+        final Cache lru = new Cache(LRU.getValue(), 1);
+
+        // when
+        final ProviderEvaluation<Object> evaluation = ProviderEvaluation.builder()
+                .value("value")
+                .variant("one")
+                .build();
+        lru.put("key", evaluation);
+
+        // then
+        assertEquals(evaluation, lru.get("key"));
+
+        // when
+        lru.clear();
+
+        // then
+        assertNull(lru.get("key"));
+    }
+}