Add ability to use whitelist conditions

Author: snuyanzin

src/main/java/net/datafaker/Faker.java

@@ -13,6 +13,7 @@
 
 import java.util.Locale;
 import java.util.Random;
+import java.util.function.Predicate;
 
 public class Faker extends BaseFaker implements BaseProviders, SportProviders, FoodProviders, EntertainmentProviders, VideoGameProviders, HealthcareProviders {
     public Faker() {
@@ -37,4 +38,8 @@ public Faker(Locale locale, RandomService randomService) {
     public Faker(FakeValuesService fakeValuesService, FakerContext context) {
         super(fakeValuesService, context);
     }
+
+    public Faker(FakeValuesService fakeValuesService, FakerContext context, Predicate<Class<?>> whiteListPredicate) {
+        super(fakeValuesService, context, whiteListPredicate);
+    }
 }

src/main/java/net/datafaker/providers/base/BaseFaker.java

@@ -19,6 +19,7 @@
 import java.util.Random;
 import java.util.concurrent.Callable;
 import java.util.function.Function;
+import java.util.function.Predicate;
 import java.util.function.Supplier;
 
 /**
@@ -28,9 +29,11 @@
  * @author ren
  */
 public class BaseFaker implements BaseProviders {
+    private static final Predicate<Class<?>> EVERY_PROVIDER_ALLOWED = t -> true;
     private final FakerContext context;
     private final FakeValuesService fakeValuesService;
     private final Map<Class<?>, AbstractProvider<?>> providersCache = new IdentityHashMap<>();
+    private final Predicate<Class<?>> whiteListPredicate;
 
     public BaseFaker() {
         this(Locale.ENGLISH);
@@ -53,8 +56,13 @@ public BaseFaker(Locale locale, RandomService randomService) {
     }
 
     public BaseFaker(FakeValuesService fakeValuesService, FakerContext context) {
+        this(fakeValuesService, context, EVERY_PROVIDER_ALLOWED);
+    }
+
+    public BaseFaker(FakeValuesService fakeValuesService, FakerContext context, Predicate<Class<?>> whiteListPredicate) {
         this.fakeValuesService = fakeValuesService;
         this.context = context;
+        this.whiteListPredicate = whiteListPredicate == null ? EVERY_PROVIDER_ALLOWED : whiteListPredicate;
         fakeValuesService.updateFakeValuesInterfaceMap(context.getLocaleChain());
     }
 
@@ -335,8 +343,13 @@ public static <T> T populate(Class<T> clazz, Schema<Object, ?> schema) {
     @SuppressWarnings("unchecked")
     public <PR extends ProviderRegistration, AP extends AbstractProvider<PR>> AP getProvider(
         Class<AP> clazz, Function<PR, AP> valueSupplier) {
-        return (AP) providersCache.computeIfAbsent(clazz, (klass) -> valueSupplier.apply(getFaker()));
-    }
+            return (AP) providersCache.computeIfAbsent(clazz, (klass) -> {
+                if (whiteListPredicate.test(klass)) {
+                    return valueSupplier.apply(getFaker());
+                }
+                throw new RuntimeException("Provider '" + klass.getName() + "' is not in white list");
+            });
+        }
 
     /**
      * This method is not needed anymore, don't use it.

src/main/java/net/datafaker/providers/food/FoodFaker.java

@@ -7,6 +7,7 @@
 
 import java.util.Locale;
 import java.util.Random;
+import java.util.function.Predicate;
 
 public class FoodFaker extends BaseFaker implements FoodProviders {
     public FoodFaker() {
@@ -32,4 +33,8 @@ public FoodFaker(Locale locale, RandomService randomService) {
     public FoodFaker(FakeValuesService fakeValuesService, FakerContext context) {
         super(fakeValuesService, context);
     }
+
+    public FoodFaker(FakeValuesService fakeValuesService, FakerContext context, Predicate<Class<?>> whiteListPredicate) {
+        super(fakeValuesService, context, whiteListPredicate);
+    }
 }

src/main/java/net/datafaker/providers/healthcare/HealthcareFaker.java

@@ -7,6 +7,7 @@
 
 import java.util.Locale;
 import java.util.Random;
+import java.util.function.Predicate;
 
 /**
  * @since 2.3.0
@@ -31,4 +32,8 @@ public HealthcareFaker(Locale locale, RandomService randomService) {
     public HealthcareFaker(FakeValuesService fakeValuesService, FakerContext context) {
         super(fakeValuesService, context);
     }
+
+    public HealthcareFaker(FakeValuesService fakeValuesService, FakerContext context, Predicate<Class<?>> whiteListPredicate) {
+        super(fakeValuesService, context, whiteListPredicate);
+    }
 }

src/main/java/net/datafaker/providers/sport/SportFaker.java

@@ -7,6 +7,7 @@
 
 import java.util.Locale;
 import java.util.Random;
+import java.util.function.Predicate;
 
 public class SportFaker extends BaseFaker implements SportProviders {
     public SportFaker() {
@@ -32,4 +33,8 @@ public SportFaker(Locale locale, RandomService randomService) {
     public SportFaker(FakeValuesService fakeValuesService, FakerContext context) {
         super(fakeValuesService, context);
     }
+
+    public SportFaker(FakeValuesService fakeValuesService, FakerContext context, Predicate<Class<?>> whiteListPredicate) {
+        super(fakeValuesService, context, whiteListPredicate);
+    }
 }

src/main/java/net/datafaker/providers/videogame/VideoGameFaker.java

@@ -7,6 +7,7 @@
 
 import java.util.Locale;
 import java.util.Random;
+import java.util.function.Predicate;
 
 public class VideoGameFaker extends BaseFaker implements VideoGameProviders {
     public VideoGameFaker() {
@@ -32,4 +33,8 @@ public VideoGameFaker(Locale locale, RandomService randomService) {
     public VideoGameFaker(FakeValuesService fakeValuesService, FakerContext context) {
         super(fakeValuesService, context);
     }
+
+    public VideoGameFaker(FakeValuesService fakeValuesService, FakerContext context, Predicate<Class<?>> whiteListPredicate) {
+        super(fakeValuesService, context, whiteListPredicate);
+    }
 }

src/test/java/net/datafaker/FakerTest.java

@@ -3,6 +3,10 @@
 import net.datafaker.annotations.Deterministic;
 import net.datafaker.providers.base.AbstractProvider;
 import net.datafaker.providers.base.BaseFaker;
+import net.datafaker.providers.base.Name;
+import net.datafaker.service.FakeValuesService;
+import net.datafaker.service.FakerContext;
+import net.datafaker.service.RandomService;
 import org.junit.jupiter.api.RepeatedTest;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.Timeout;
@@ -27,6 +31,7 @@
 import java.util.stream.Collectors;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatNoException;
 import static org.assertj.core.api.Assertions.assertThatThrownBy;
 import static org.reflections.scanners.Scanners.SubTypes;
 
@@ -393,4 +398,29 @@ void testDeterministicAndNonDeterministicProvidersReturnValues() {
             }
         }
     }
+
+    @Test
+    void whitelistTest() {
+        final Faker fakerWithoutWhiteList = new Faker();
+        final Faker fakerWithEmptyWhiteList = new Faker(new FakeValuesService(), new FakerContext(Locale.ENGLISH, new RandomService()), c -> false);
+        final Faker fakerWithFullWhiteList = new Faker(new FakeValuesService(), new FakerContext(Locale.ENGLISH, new RandomService()), c -> true);
+        final Faker fakerWithWithoutNameInWhiteList = new Faker(new FakeValuesService(), new FakerContext(Locale.ENGLISH, new RandomService()), c -> c != Name.class);
+
+        assertThatThrownBy(() -> fakerWithEmptyWhiteList.expression("#{Address.country}"))
+            .hasRootCauseMessage("Provider 'net.datafaker.providers.base.Address' is not in white list");
+
+        assertThatNoException()
+            .isThrownBy(() -> fakerWithoutWhiteList.expression("#{Address.country}"));
+
+        assertThatNoException()
+            .isThrownBy(() -> fakerWithFullWhiteList.expression("#{Address.country}"));
+
+        assertThatNoException()
+            .isThrownBy(() -> fakerWithWithoutNameInWhiteList.expression("#{Address.country}"));
+
+
+        assertThatThrownBy(() -> fakerWithEmptyWhiteList.expression("#{Name.fullName}"))
+            .hasRootCauseMessage("Provider 'net.datafaker.providers.base.Name' is not in white list");
+
+    }
 }