diff --git a/.gitignore b/.gitignore index bd26102..31051c7 100644 --- a/.gitignore +++ b/.gitignore @@ -15,3 +15,4 @@ target # used for spec compliance tooling java-report.json +.worktrees/ diff --git a/src/main/java/dev/openfeature/sdk/FeatureProvider.java b/src/main/java/dev/openfeature/sdk/FeatureProvider.java index a010e55..54ca2dd 100644 --- a/src/main/java/dev/openfeature/sdk/FeatureProvider.java +++ b/src/main/java/dev/openfeature/sdk/FeatureProvider.java @@ -185,6 +185,38 @@ public interface FeatureProvider { // Intentionally left blank } + /** + * This method is called before a provider is used to evaluate flags, with the + * bound domain supplied when the provider is registered to a named client. + * + *

+ * The default provider is initialized with a {@code null} domain. Providers that + * maintain per-domain state (for example a persistent cache) should override this + * method and declare themselves {@linkplain #isDomainScoped() domain-scoped}. + *

+ * + * @param evaluationContext the global evaluation context + * @param domain the bound domain, or {@code null} for the default provider + */ + default void initialize(EvaluationContext evaluationContext, String domain) throws Exception { + initialize(evaluationContext); + } + + /** + * Returns whether this provider maintains state specific to a single domain that + * cannot be shared across domains. + * + *

+ * Domain-scoped providers may only be bound to one domain within a single API + * instance. + *

+ * + * @return {@code true} if this provider is domain-scoped + */ + default boolean isDomainScoped() { + return false; + } + /** * Called when a provider is about to be replaced or the SDK is shutting down. Providers can * override this method if they have resources to release (background threads, connections, diff --git a/src/main/java/dev/openfeature/sdk/FeatureProviderStateManager.java b/src/main/java/dev/openfeature/sdk/FeatureProviderStateManager.java index cbdb4d8..eb461d7 100644 --- a/src/main/java/dev/openfeature/sdk/FeatureProviderStateManager.java +++ b/src/main/java/dev/openfeature/sdk/FeatureProviderStateManager.java @@ -19,11 +19,15 @@ class FeatureProviderStateManager implements EventProviderListener { } public void initialize(EvaluationContext evaluationContext) throws Exception { + initialize(evaluationContext, null); + } + + public void initialize(EvaluationContext evaluationContext, String domain) throws Exception { if (isInitialized.getAndSet(true)) { return; } try { - delegate.initialize(evaluationContext); + delegate.initialize(evaluationContext, domain); setState(ProviderState.READY); } catch (OpenFeatureError openFeatureError) { if (ErrorCode.PROVIDER_FATAL.equals(openFeatureError.getErrorCode())) { diff --git a/src/main/java/dev/openfeature/sdk/ProviderRepository.java b/src/main/java/dev/openfeature/sdk/ProviderRepository.java index 7fcb8f4..816f05a 100644 --- a/src/main/java/dev/openfeature/sdk/ProviderRepository.java +++ b/src/main/java/dev/openfeature/sdk/ProviderRepository.java @@ -169,6 +169,7 @@ class ProviderRepository { throw new IllegalStateException("Provider cannot be set while repository is shutting down"); } FeatureProviderStateManager existing = getExistingStateManagerForProvider(newProvider); + validateDomainScopedBinding(domain, newProvider); if (existing == null) { openFeatureAPI.registerGlobalProvider(newProvider); newStateManager = new FeatureProviderStateManager(newProvider); @@ -185,29 +186,68 @@ class ProviderRepository { } if (waitForInit) { - initializeProvider(newStateManager, afterInit, afterShutdown, afterError, oldStateManager); + initializeProvider(domain, newStateManager, afterInit, afterShutdown, afterError, oldStateManager); } else { taskExecutor.submit(() -> { // initialization happens in a different thread if we're not waiting for it - initializeProvider(newStateManager, afterInit, afterShutdown, afterError, oldStateManager); + initializeProvider(domain, newStateManager, afterInit, afterShutdown, afterError, oldStateManager); }); } } + private void validateDomainScopedBinding(String domain, FeatureProvider newProvider) { + if (!newProvider.isDomainScoped()) { + return; + } + + // a re-set to the identical binding is always allowed (it's a no-op) + boolean alreadyBoundHere = domain == null + ? isDefaultProviderInstance(newProvider) + : getBoundDomainsForProviderInstance(newProvider).contains(domain); + if (alreadyBoundHere) { + return; + } + + // any other existing binding means this instance would span more than one domain + if (isDefaultProviderInstance(newProvider) + || !getBoundDomainsForProviderInstance(newProvider).isEmpty()) { + throw new IllegalArgumentException("Domain-scoped provider cannot be bound to more than one domain"); + } + } + + private boolean isDefaultProviderInstance(FeatureProvider provider) { + return defaultStateManger.get().getProvider() == provider; + } + + private List getBoundDomainsForProviderInstance(FeatureProvider provider) { + return stateManagers.entrySet().stream() + .filter(entry -> entry.getValue().getProvider() == provider) + .map(Map.Entry::getKey) + .collect(Collectors.toList()); + } + private FeatureProviderStateManager getExistingStateManagerForProvider(FeatureProvider provider) { for (FeatureProviderStateManager stateManager : stateManagers.values()) { - if (stateManager.hasSameProvider(provider)) { + if (matchesProvider(stateManager.getProvider(), provider)) { return stateManager; } } FeatureProviderStateManager defaultFeatureProviderStateManager = defaultStateManger.get(); - if (defaultFeatureProviderStateManager.hasSameProvider(provider)) { + if (matchesProvider(defaultFeatureProviderStateManager.getProvider(), provider)) { return defaultFeatureProviderStateManager; } return null; } + private boolean matchesProvider(FeatureProvider registered, FeatureProvider candidate) { + if (candidate.isDomainScoped()) { + return registered == candidate; + } + return registered.equals(candidate); + } + private void initializeProvider( + String domain, FeatureProviderStateManager newManager, Consumer afterInit, Consumer afterShutdown, @@ -215,7 +255,7 @@ class ProviderRepository { FeatureProviderStateManager oldManager) { try { if (ProviderState.NOT_READY.equals(newManager.getState())) { - newManager.initialize(openFeatureAPI.getEvaluationContext()); + newManager.initialize(openFeatureAPI.getEvaluationContext(), domain); afterInit.accept(newManager.getProvider()); } shutDownOld(oldManager, afterShutdown); diff --git a/src/main/java/dev/openfeature/sdk/multiprovider/MultiProvider.java b/src/main/java/dev/openfeature/sdk/multiprovider/MultiProvider.java index cc6fb8d..00611ed 100644 --- a/src/main/java/dev/openfeature/sdk/multiprovider/MultiProvider.java +++ b/src/main/java/dev/openfeature/sdk/multiprovider/MultiProvider.java @@ -76,14 +76,24 @@ public class MultiProvider extends EventProvider { } /** - * Initialize the provider. + * {@inheritDoc} * - * @param evaluationContext evaluation context * @throws Exception on error (e.g. wrapped {@link java.util.concurrent.ExecutionException} * from a failing provider) */ @Override public void initialize(EvaluationContext evaluationContext) throws Exception { + initialize(evaluationContext, null); + } + + /** + * {@inheritDoc} + * + * @throws Exception on error (e.g. wrapped {@link java.util.concurrent.ExecutionException} + * from a failing provider) + */ + @Override + public void initialize(EvaluationContext evaluationContext, String domain) throws Exception { var metadataBuilder = MultiProviderMetadata.builder().name(NAME); HashMap providersMetadata = new HashMap<>(); @@ -98,7 +108,7 @@ public class MultiProvider extends EventProvider { Collection> tasks = new ArrayList<>(providers.size()); for (FeatureProvider provider : providers.values()) { tasks.add(() -> { - provider.initialize(evaluationContext); + provider.initialize(evaluationContext, domain); return null; }); Metadata providerMetadata = provider.getMetadata();