statefun-flink/statefun-flink-core/src/test/java/org/apache/flink/statefun/flink/core/jsonmodule/RemoteModuleTest.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.flink.statefun.flink.core.jsonmodule;

import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.Matchers.hasKey;
import static org.hamcrest.Matchers.not;
import static org.hamcrest.Matchers.notNullValue;
import static org.hamcrest.Matchers.nullValue;

import java.net.URL;
import java.util.HashMap;
import java.util.Map;
import org.apache.flink.shaded.jackson2.com.fasterxml.jackson.databind.ObjectMapper;
import org.apache.flink.statefun.extensions.ComponentBinder;
import org.apache.flink.statefun.extensions.ComponentJsonObject;
import org.apache.flink.statefun.extensions.ExtensionModule;
import org.apache.flink.statefun.flink.core.StatefulFunctionsUniverse;
import org.apache.flink.statefun.flink.core.message.MessageFactoryKey;
import org.apache.flink.statefun.flink.core.message.MessageFactoryType;
import org.apache.flink.statefun.sdk.EgressType;
import org.apache.flink.statefun.sdk.FunctionType;
import org.apache.flink.statefun.sdk.IngressType;
import org.apache.flink.statefun.sdk.StatefulFunction;
import org.apache.flink.statefun.sdk.StatefulFunctionProvider;
import org.apache.flink.statefun.sdk.TypeName;
import org.apache.flink.statefun.sdk.io.EgressIdentifier;
import org.apache.flink.statefun.sdk.io.EgressSpec;
import org.apache.flink.statefun.sdk.io.IngressIdentifier;
import org.apache.flink.statefun.sdk.io.IngressSpec;
import org.apache.flink.statefun.sdk.spi.StatefulFunctionModule;
import org.junit.Test;

public final class RemoteModuleTest {

  private final String modulePath = "remote-module/module.yaml";

  @Test
  public void exampleUsage() {
    StatefulFunctionModule module = fromPath(modulePath);

    assertThat(module, notNullValue());
  }

  @Test
  public void testComponents() {
    StatefulFunctionModule module = fromPath(modulePath);

    StatefulFunctionsUniverse universe = emptyUniverse();
    setupUniverse(universe, module, new TestComponentBindersModule());

    assertThat(universe.functions(), hasKey(TestComponentBinder1.TEST_FUNCTION_TYPE));
    assertThat(universe.ingress(), hasKey(TestComponentBinder2.TEST_INGRESS.id()));
    assertThat(universe.egress(), hasKey(TestComponentBinder3.TEST_EGRESS.id()));
  }

  private static StatefulFunctionModule fromPath(String path) {
    URL moduleUrl = RemoteModuleTest.class.getClassLoader().getResource(path);
    assertThat(moduleUrl, not(nullValue()));
    ObjectMapper mapper = JsonServiceLoader.mapper();
    return JsonServiceLoader.fromUrl(mapper, moduleUrl);
  }

  private static StatefulFunctionsUniverse emptyUniverse() {
    return new StatefulFunctionsUniverse(
        MessageFactoryKey.forType(MessageFactoryType.WITH_PROTOBUF_PAYLOADS, null));
  }

  private static void setupUniverse(
      StatefulFunctionsUniverse universe,
      StatefulFunctionModule functionModule,
      ExtensionModule extensionModule) {
    final Map<String, String> globalConfig = new HashMap<>();
    extensionModule.configure(globalConfig, universe);
    functionModule.configure(globalConfig, universe);
  }

  private static class TestComponentBindersModule implements ExtensionModule {
    @Override
    public void configure(Map<String, String> globalConfigurations, Binder binder) {
      binder.bindExtension(
          TypeName.parseFrom("com.foo.bar/test.component.1"), new TestComponentBinder1());
      binder.bindExtension(
          TypeName.parseFrom("com.foo.bar/test.component.2"), new TestComponentBinder2());
      binder.bindExtension(
          TypeName.parseFrom("com.foo.bar/test.component.3"), new TestComponentBinder3());
    }
  }

  private static class TestComponentBinder1 implements ComponentBinder {

    private static final FunctionType TEST_FUNCTION_TYPE =
        new FunctionType("test", "function.type");

    @Override
    public void bind(
        ComponentJsonObject component, StatefulFunctionModule.Binder remoteModuleBinder) {
      remoteModuleBinder.bindFunctionProvider(TEST_FUNCTION_TYPE, new TestFunctionProvider());
    }
  }

  private static class TestComponentBinder2 implements ComponentBinder {
    private static final TestIngressSpec TEST_INGRESS = new TestIngressSpec();

    @Override
    public void bind(
        ComponentJsonObject component, StatefulFunctionModule.Binder remoteModuleBinder) {
      remoteModuleBinder.bindIngress(TEST_INGRESS);
    }
  }

  private static class TestComponentBinder3 implements ComponentBinder {
    private static final TestEgressSpec TEST_EGRESS = new TestEgressSpec();

    @Override
    public void bind(
        ComponentJsonObject component, StatefulFunctionModule.Binder remoteModuleBinder) {
      remoteModuleBinder.bindEgress(TEST_EGRESS);
    }
  }

  private static class TestFunctionProvider implements StatefulFunctionProvider {
    @Override
    public StatefulFunction functionOfType(FunctionType type) {
      throw new UnsupportedOperationException();
    }
  }

  private static class TestIngressSpec implements IngressSpec<String> {
    @Override
    public IngressIdentifier<String> id() {
      return new IngressIdentifier<>(String.class, "test-namespace", "test-ingress");
    }

    @Override
    public IngressType type() {
      throw new UnsupportedOperationException();
    }
  }

  private static class TestEgressSpec implements EgressSpec<String> {
    @Override
    public EgressIdentifier<String> id() {
      return new EgressIdentifier<>("test-namespace", "test-egress", String.class);
    }

    @Override
    public EgressType type() {
      throw new UnsupportedOperationException();
    }
  }
}