feat: add Togglz provider

pom.xml

@@ -33,6 +33,7 @@
         <module>providers/go-feature-flag</module>
         <module>providers/jsonlogic-eval-provider</module>
         <module>providers/env-var</module>
+        <module>providers/togglz</module>
     </modules>
 
     <scm>

providers/togglz/README.md

@@ -0,0 +1,7 @@
+# Unofficial Togglz OpenFeature Provider for Java
+
+## Usage
+See [TogglzProviderTest.java](./src/test/java/dev/openfeature/contrib/providers/togglz/TogglzProviderTest.java)
+
+### References
+* [Togglz](https://www.togglz.org)

providers/togglz/lombok.config

@@ -0,0 +1,5 @@
+# This file is needed to avoid errors throw by findbugs when working with lombok.
+lombok.addSuppressWarnings = true
+lombok.addLombokGeneratedAnnotation = true
+config.stopBubbling = true
+lombok.extern.findbugs.addSuppressFBWarnings = true

providers/togglz/pom.xml

@@ -0,0 +1,40 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://maven.apache.org/POM/4.0.0"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <parent>
+        <groupId>dev.openfeature.contrib</groupId>
+        <artifactId>parent</artifactId>
+        <version>0.1.0</version>
+        <relativePath>../../pom.xml</relativePath>
+    </parent>
+    <groupId>dev.openfeature.contrib.providers</groupId>
+    <artifactId>togglz</artifactId>
+    <version>0.0.1</version> <!--x-release-please-version -->
+
+    <name>togglz</name>
+    <description>togglz provider for Java</description>
+    <url>https://www.togglz.org/</url>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.togglz</groupId>
+            <artifactId>togglz-core</artifactId>
+            <version>4.3.0</version>
+        </dependency>
+
+        <dependency>
+            <groupId>org.slf4j</groupId>
+            <artifactId>slf4j-api</artifactId>
+            <version>2.0.7</version>
+        </dependency>
+
+        <dependency>
+            <groupId>org.apache.logging.log4j</groupId>
+            <artifactId>log4j-slf4j2-impl</artifactId>
+            <version>2.20.0</version>
+            <scope>test</scope>
+        </dependency>
+
+    </dependencies>
+</project>

providers/togglz/src/main/java/dev/openfeature/contrib/providers/togglz/TogglzProvider.java

@@ -0,0 +1,99 @@
+package dev.openfeature.contrib.providers.togglz;
+
+import dev.openfeature.sdk.EvaluationContext;
+import dev.openfeature.sdk.EventProvider;
+import dev.openfeature.sdk.Metadata;
+import dev.openfeature.sdk.ProviderEvaluation;
+import dev.openfeature.sdk.ProviderState;
+import dev.openfeature.sdk.Reason;
+import dev.openfeature.sdk.Value;
+import dev.openfeature.sdk.exceptions.FlagNotFoundError;
+import dev.openfeature.sdk.exceptions.GeneralError;
+import dev.openfeature.sdk.exceptions.ProviderNotReadyError;
+import dev.openfeature.sdk.exceptions.TypeMismatchError;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.extern.slf4j.Slf4j;
+import org.togglz.core.Feature;
+
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * Provider implementation for Togglz.
+ */
+@AllArgsConstructor
+@Slf4j
+public class TogglzProvider extends EventProvider {
+
+    @Getter
+    private static final String NAME = "Togglz Provider";
+    public static final String NOT_IMPLEMENTED =
+        "Not implemented - provider does not support this type. Only boolean is supported.";
+
+    private Map<String, Feature> features = new HashMap<>();
+
+    @Getter
+    private ProviderState state = ProviderState.NOT_READY;
+
+    public TogglzProvider(Collection<Feature> featuresCollection) {
+        featuresCollection.forEach(feature -> features.put(feature.name(), feature));
+    }
+
+    /**
+     * Initialize the provider.
+     * @param evaluationContext evaluation context
+     * @throws Exception on error
+     */
+    @Override
+    public void initialize(EvaluationContext evaluationContext) throws Exception {
+        super.initialize(evaluationContext);
+        state = ProviderState.READY;
+        log.debug("finished initializing provider, state: {}", state);
+    }
+
+    @Override
+    public Metadata getMetadata() {
+        return () -> NAME;
+    }
+
+    @Override
+    public ProviderEvaluation<Boolean> getBooleanEvaluation(String key, Boolean defaultValue, EvaluationContext ctx) {
+        if (!ProviderState.READY.equals(state)) {
+            if (ProviderState.NOT_READY.equals(state)) {
+                throw new ProviderNotReadyError("provider not yet initialized");
+            }
+            throw new GeneralError("unknown error");
+        }
+        Feature feature = features.get(key);
+        if (feature == null) {
+            throw new FlagNotFoundError("flag " + key + " not found");
+        }
+        boolean featureBooleanValue = feature.isActive();
+        return ProviderEvaluation.<Boolean>builder()
+            .value(featureBooleanValue)
+            .reason(Reason.TARGETING_MATCH.name())
+            .build();
+    }
+
+    @Override
+    public ProviderEvaluation<String> getStringEvaluation(String key, String defaultValue, EvaluationContext ctx) {
+        throw new TypeMismatchError(NOT_IMPLEMENTED);
+    }
+
+    @Override
+    public ProviderEvaluation<Integer> getIntegerEvaluation(String key, Integer defaultValue, EvaluationContext ctx) {
+        throw new TypeMismatchError(NOT_IMPLEMENTED);
+    }
+
+    @Override
+    public ProviderEvaluation<Double> getDoubleEvaluation(String key, Double defaultValue, EvaluationContext ctx) {
+        throw new TypeMismatchError(NOT_IMPLEMENTED);
+    }
+
+    @Override
+    public ProviderEvaluation<Value> getObjectEvaluation(String s, Value value, EvaluationContext evaluationContext) {
+        throw new TypeMismatchError(NOT_IMPLEMENTED);
+    }
+}

providers/togglz/src/test/java/dev/openfeature/contrib/providers/togglz/TestFeatures.java

@@ -0,0 +1,18 @@
+package dev.openfeature.contrib.providers.togglz;
+
+import org.togglz.core.Feature;
+import org.togglz.core.annotation.Label;
+import org.togglz.core.context.FeatureContext;
+
+public enum TestFeatures implements Feature {
+
+    @Label("First Feature")
+    FEATURE_ONE,
+
+    @Label("Second Feature")
+    FEATURE_TWO;
+
+    public boolean isActive() {
+        return FeatureContext.getFeatureManager().isActive(this);
+    }
+}

providers/togglz/src/test/java/dev/openfeature/contrib/providers/togglz/TogglzProviderTest.java

@@ -0,0 +1,81 @@
+package dev.openfeature.contrib.providers.togglz;
+
+import dev.openfeature.sdk.Client;
+import dev.openfeature.sdk.FeatureProvider;
+import dev.openfeature.sdk.ImmutableContext;
+import dev.openfeature.sdk.OpenFeatureAPI;
+import dev.openfeature.sdk.exceptions.FlagNotFoundError;
+import dev.openfeature.sdk.exceptions.ProviderNotReadyError;
+import dev.openfeature.sdk.exceptions.TypeMismatchError;
+import lombok.SneakyThrows;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.togglz.core.context.StaticFeatureManagerProvider;
+import org.togglz.core.manager.FeatureManager;
+import org.togglz.core.manager.FeatureManagerBuilder;
+import org.togglz.core.repository.FeatureState;
+import org.togglz.core.repository.StateRepository;
+import org.togglz.core.repository.mem.InMemoryStateRepository;
+import org.togglz.core.user.NoOpUserProvider;
+
+import java.util.Arrays;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+class TogglzProviderTest {
+
+    private FeatureProvider featureProvider;
+
+    private Client client;
+
+    @BeforeEach
+    void setUp() throws Exception {
+        StateRepository stateRepository = new InMemoryStateRepository();
+        stateRepository.setFeatureState(new FeatureState(TestFeatures.FEATURE_ONE, true));
+        stateRepository.setFeatureState(new FeatureState(TestFeatures.FEATURE_TWO, false));
+
+        FeatureManager featureManager = new FeatureManagerBuilder()
+            .featureEnums(TestFeatures.class)
+            .stateRepository(stateRepository)
+            .userProvider(new NoOpUserProvider())
+            .build();
+        StaticFeatureManagerProvider.setFeatureManager(featureManager);
+
+        OpenFeatureAPI api = OpenFeatureAPI.getInstance();
+        featureProvider = new TogglzProvider(Arrays.asList(TestFeatures.values()));
+        api.setProviderAndWait(featureProvider);
+        client = api.getClient();
+    }
+
+    @Test
+    void getBooleanEvaluation() {
+        assertEquals(true, featureProvider.getBooleanEvaluation(TestFeatures.FEATURE_ONE.name(), false, new ImmutableContext()).getValue());
+        assertEquals(true, client.getBooleanValue(TestFeatures.FEATURE_ONE.name(), false));
+        assertEquals(false, featureProvider.getBooleanEvaluation(TestFeatures.FEATURE_TWO.name(), false, new ImmutableContext()).getValue());
+        assertEquals(false, client.getBooleanValue(TestFeatures.FEATURE_TWO.name(), false));
+    }
+
+    @Test
+    void notFound() {
+        assertThrows(FlagNotFoundError.class, () -> {
+            featureProvider.getBooleanEvaluation("not-found-flag", false, new ImmutableContext());
+        });
+    }
+
+    @Test
+    void typeMismatch() {
+        assertThrows(TypeMismatchError.class, () -> {
+            featureProvider.getStringEvaluation(TestFeatures.FEATURE_ONE.name(), "default_value", new ImmutableContext());
+        });
+    }
+
+    @SneakyThrows
+    @Test
+    void shouldThrowIfNotInitialized() {
+        TogglzProvider togglzProvider = new TogglzProvider(Arrays.asList(TestFeatures.values()));
+
+        // ErrorCode.PROVIDER_NOT_READY should be returned when evaluated via the client
+        assertThrows(ProviderNotReadyError.class, ()-> togglzProvider.getBooleanEvaluation("fail_not_initialized", false, new ImmutableContext()));
+    }
+}

providers/togglz/src/test/resources/log4j2-test.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Configuration status="DEBUG">
+    <Appenders>
+        <Console name="consoleLogger" target="SYSTEM_OUT">
+            <PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n"/>
+        </Console>
+    </Appenders>
+    <Loggers>
+        <Root level="trace">
+            <AppenderRef ref="consoleLogger"/>
+        </Root>
+    </Loggers>
+</Configuration>

providers/togglz/version.txt

@@ -0,0 +1 @@
+0.0.1