fix: strategy evaluation is OR based. (#370)

Due to a bug in Yggdrasil, multiple instances of the same custom
strategy overwrote each other so last one won. After this bug fix,
Yggdrasil again evaluates all custom strategies on an OR base, so if any
are true, the flag will be true

fixes: #369

Author: chriswk

pom.xml

@@ -61,7 +61,7 @@
         <dependency>
             <groupId>io.getunleash</groupId>
             <artifactId>yggdrasil-engine</artifactId>
-            <version>0.4.5</version>
+            <version>0.5.0</version>
         </dependency>
         <dependency>
             <groupId>com.google.code.gson</groupId>

src/main/java/io/getunleash/impactmetrics/MetricFlagContext.java

@@ -3,7 +3,9 @@
 import io.getunleash.UnleashContext;
 import java.util.List;
 
-/** @deprecated MetricFlagContext will be removed in a future release. */
+/**
+ * @deprecated MetricFlagContext will be removed in a future release.
+ */
 @Deprecated(since = "12.1.1", forRemoval = true)
 public class MetricFlagContext {
     private final List<String> flagNames;

src/main/java/io/getunleash/impactmetrics/MetricsAPI.java

@@ -17,14 +17,18 @@ public interface MetricsAPI {
 
     public void incrementCounter(String name, long value);
 
-    /** @deprecated MetricFlagContext will be removed in a future release. */
+    /**
+     * @deprecated MetricFlagContext will be removed in a future release.
+     */
     @Deprecated(since = "12.1.1", forRemoval = true)
     public void incrementCounter(
             String name, @Nullable Long value, @Nullable MetricFlagContext flagContext);
 
     public void updateGauge(String name, double value);
 
-    /** @deprecated MetricFlagContext will be removed in a future release. */
+    /**
+     * @deprecated MetricFlagContext will be removed in a future release.
+     */
     @Deprecated(since = "12.1.1", forRemoval = true)
     public void updateGauge(String name, double value, @Nullable MetricFlagContext flagContext);
 
@@ -36,7 +40,9 @@ public void incrementCounter(
 
     public void observeHistogram(String name, double value);
 
-    /** @deprecated MetricFlagContext will be removed in a future release. */
+    /**
+     * @deprecated MetricFlagContext will be removed in a future release.
+     */
     @Deprecated(since = "12.1.1", forRemoval = true)
     public void observeHistogram(
             String name, double value, @Nullable MetricFlagContext flagContext);

src/test/java/io/getunleash/strategies/custom/ConstraintEvaluatorCustom.java

@@ -0,0 +1,17 @@
+package io.getunleash.strategies.custom;
+
+import io.getunleash.UnleashContext;
+import io.getunleash.strategy.Strategy;
+import java.util.Map;
+
+public class ConstraintEvaluatorCustom implements Strategy {
+    @Override
+    public String getName() {
+        return "repeated";
+    }
+
+    @Override
+    public boolean isEnabled(Map<String, String> parameters, UnleashContext context) {
+        return context.getProperties().get("myFancy").equals(parameters.get("myFancy"));
+    }
+}

src/test/java/io/getunleash/strategies/custom/RepeatedCustomStrategyTest.java

@@ -0,0 +1,34 @@
+package io.getunleash.strategies.custom;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import io.getunleash.DefaultUnleash;
+import io.getunleash.UnleashContext;
+import io.getunleash.util.ResourceReader;
+import io.getunleash.util.UnleashConfig;
+import java.util.Optional;
+import org.junit.jupiter.api.Test;
+
+public class RepeatedCustomStrategyTest {
+    private String loadMockFeatures(String path) {
+        return ResourceReader.readResourceAsString(path);
+    }
+
+    @Test
+    public void
+            repeated_custom_strategy_evaluates_to_true_if_any_custom_strategy_evaluates_to_true() {
+        UnleashConfig config =
+                UnleashConfig.builder()
+                        .unleashAPI("http://test:4242")
+                        .appName("multiple_connection")
+                        .instanceId("repeated_custom_strategy")
+                        .toggleBootstrapProvider(
+                                () ->
+                                        Optional.of(
+                                                loadMockFeatures("repeated_custom_strategy.json")))
+                        .build();
+        var myUnleash = new DefaultUnleash(config, new ConstraintEvaluatorCustom());
+        UnleashContext context = UnleashContext.builder().addProperty("myFancy", "one").build();
+        assertThat(myUnleash.isEnabled("repeated.custom", context)).isTrue();
+    }
+}

src/test/resources/repeated_custom_strategy.json

@@ -0,0 +1,24 @@
+{
+    "version": 2,
+    "features": [
+        {
+            "name": "repeated.custom",
+            "enabled": true,
+            "strategies": [
+                {
+                    "name": "repeated",
+                    "parameters": {
+                        "myFancy": "one"
+                    }
+
+                },
+                {
+                    "name": "repeated",
+                    "parameters": {
+                        "myFancy": "two"
+                    }
+                }
+            ]
+        }
+    ]
+}