chore: Change 'forServer' boolean to format enum (#45)

* use 'format' instead of 'forServer' with enum

Author: typotter

src/main/java/cloud/eppo/api/Configuration.java

@@ -79,10 +79,14 @@ private Configuration(
     if (flagConfigJson != null && flagConfigJson.length != 0) {
       try {
         JsonNode jNode = mapper.readTree(flagConfigJson);
-        ((ObjectNode) jNode).put("forServer", !isConfigObfuscated);
+        FlagConfigResponse.Format format =
+            isConfigObfuscated
+                ? FlagConfigResponse.Format.CLIENT
+                : FlagConfigResponse.Format.SERVER;
+        ((ObjectNode) jNode).put("format", format.toString());
         flagConfigJson = mapper.writeValueAsBytes(jNode);
       } catch (IOException e) {
-        log.error("Error adding `forServer` field to FlagConfigResponse JSON");
+        log.error("Error adding `format` field to FlagConfigResponse JSON");
       }
     }
     this.flagConfigJson = flagConfigJson;
@@ -183,7 +187,10 @@ public Builder(byte[] flagJson, boolean isConfigObfuscated) {
     }
 
     public Builder(byte[] flagJson, FlagConfigResponse flagConfigResponse) {
-      this(flagJson, flagConfigResponse, !flagConfigResponse.isForServer());
+      this(
+          flagJson,
+          flagConfigResponse,
+          flagConfigResponse.getFormat() == FlagConfigResponse.Format.CLIENT);
     }
 
     /** Use this constructor when the FlagConfigResponse has the `forServer` field populated. */

src/main/java/cloud/eppo/ufc/dto/FlagConfigResponse.java

@@ -6,24 +6,24 @@
 public class FlagConfigResponse {
   private final Map<String, FlagConfig> flags;
   private final Map<String, BanditReference> banditReferences;
-  private final boolean forServer;
-
-  public FlagConfigResponse(
-      Map<String, FlagConfig> flags, Map<String, BanditReference> banditReferences) {
-    this(flags, banditReferences, false);
-  }
+  private final Format format;
 
   public FlagConfigResponse(
       Map<String, FlagConfig> flags,
       Map<String, BanditReference> banditReferences,
-      boolean isConfigObfuscated) {
+      Format dataFormat) {
     this.flags = flags;
     this.banditReferences = banditReferences;
-    this.forServer = !isConfigObfuscated;
+    format = dataFormat;
+  }
+
+  public FlagConfigResponse(
+      Map<String, FlagConfig> flags, Map<String, BanditReference> banditReferences) {
+    this(flags, banditReferences, Format.SERVER);
   }
 
   public FlagConfigResponse() {
-    this(new ConcurrentHashMap<>(), new ConcurrentHashMap<>(), false);
+    this(new ConcurrentHashMap<>(), new ConcurrentHashMap<>(), Format.SERVER);
   }
 
   public Map<String, FlagConfig> getFlags() {
@@ -34,7 +34,12 @@ public Map<String, BanditReference> getBanditReferences() {
     return this.banditReferences;
   }
 
-  public boolean isForServer() {
-    return this.forServer;
+  public Format getFormat() {
+    return format;
+  }
+
+  public enum Format {
+    SERVER,
+    CLIENT
   }
 }

src/main/java/cloud/eppo/ufc/dto/adapters/FlagConfigResponseDeserializer.java

@@ -49,8 +49,11 @@ public FlagConfigResponse deserialize(JsonParser jp, DeserializationContext ctxt
     }
 
     // Default is to assume that the config is not obfuscated.
-    JsonNode forServerNode = rootNode.get("forServer");
-    boolean isConfigObfuscated = forServerNode != null && !forServerNode.asBoolean();
+    JsonNode formatNode = rootNode.get("format");
+    FlagConfigResponse.Format dataFormat =
+        formatNode == null
+            ? FlagConfigResponse.Format.SERVER
+            : FlagConfigResponse.Format.valueOf(formatNode.asText());
 
     Map<String, FlagConfig> flags = new ConcurrentHashMap<>();
 
@@ -78,7 +81,7 @@ public FlagConfigResponse deserialize(JsonParser jp, DeserializationContext ctxt
       }
     }
 
-    return new FlagConfigResponse(flags, banditReferences, isConfigObfuscated);
+    return new FlagConfigResponse(flags, banditReferences, dataFormat);
   }
 
   private FlagConfig deserializeFlag(JsonNode jsonNode) {

src/test/java/cloud/eppo/api/ConfigurationBuilderTest.java

@@ -1,7 +1,6 @@
 package cloud.eppo.api;
 
-import static org.junit.jupiter.api.Assertions.assertFalse;
-import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.junit.jupiter.api.Assertions.*;
 
 import cloud.eppo.ufc.dto.FlagConfigResponse;
 import cloud.eppo.ufc.dto.adapters.EppoModule;
@@ -16,14 +15,14 @@ public class ConfigurationBuilderTest {
 
   @Test
   public void testHydrateConfigFromBytesForServer_true() {
-    byte[] jsonBytes = "{ \"forServer\": true, \"flags\":{} }".getBytes();
+    byte[] jsonBytes = "{ \"format\": \"SERVER\", \"flags\":{} }".getBytes();
     Configuration config = new Configuration.Builder(jsonBytes).build();
     assertFalse(config.isConfigObfuscated());
   }
 
   @Test
   public void testHydrateConfigFromBytesForServer_false() {
-    byte[] jsonBytes = "{ \"forServer\": false, \"flags\":{} }".getBytes();
+    byte[] jsonBytes = "{ \"format\": \"CLIENT\", \"flags\":{} }".getBytes();
     Configuration config = new Configuration.Builder(jsonBytes).build();
     assertTrue(config.isConfigObfuscated());
   }
@@ -38,7 +37,7 @@ public void testBuildConfigAddsForServer_true() throws IOException {
     FlagConfigResponse rehydratedConfig =
         mapper.readValue(serializedFlags, FlagConfigResponse.class);
 
-    assertTrue(rehydratedConfig.isForServer());
+    assertEquals(rehydratedConfig.getFormat(), FlagConfigResponse.Format.SERVER);
   }
 
   @Test
@@ -51,6 +50,6 @@ public void testBuildConfigAddsForServer_false() throws IOException {
     FlagConfigResponse rehydratedConfig =
         mapper.readValue(serializedFlags, FlagConfigResponse.class);
 
-    assertFalse(rehydratedConfig.isForServer());
+    assertEquals(rehydratedConfig.getFormat(), FlagConfigResponse.Format.CLIENT);
   }
 }