feat: add http service framework (#50)

* feat: add http service framework

* refactor: add functional interface

Author: aaron-steinfeld

platform-http-service-framework/build.gradle.kts

@@ -0,0 +1,24 @@
+plugins {
+  `java-library`
+  id("org.hypertrace.publish-plugin")
+}
+
+dependencies {
+  api(project(":platform-service-framework"))
+  api("org.hypertrace.core.grpcutils:grpc-client-utils:0.7.6")
+  api("com.typesafe:config:1.4.2")
+  api("javax.servlet:javax.servlet-api:4.0.1")
+  api("com.google.inject:guice:5.1.0")
+  api(project(":service-framework-spi"))
+
+  implementation("org.slf4j:slf4j-api:1.7.36")
+  implementation("com.google.inject.extensions:guice-servlet:5.1.0")
+  implementation("com.google.guava:guava:31.1-jre")
+  implementation("org.eclipse.jetty:jetty-servlet:9.4.48.v20220622")
+  implementation("org.eclipse.jetty:jetty-server:9.4.48.v20220622")
+  implementation("org.eclipse.jetty:jetty-servlets:9.4.48.v20220622")
+
+  annotationProcessor("org.projectlombok:lombok:1.18.24")
+  compileOnly("org.projectlombok:lombok:1.18.24")
+
+}

platform-http-service-framework/src/main/java/org/hypertrace/core/serviceframework/http/HttpContainer.java

@@ -0,0 +1,11 @@
+package org.hypertrace.core.serviceframework.http;
+
+public interface HttpContainer {
+  void start();
+
+  void blockUntilStopped();
+
+  void stop();
+
+  boolean isStopped();
+}

platform-http-service-framework/src/main/java/org/hypertrace/core/serviceframework/http/HttpContainerEnvironment.java

@@ -0,0 +1,13 @@
+package org.hypertrace.core.serviceframework.http;
+
+import com.typesafe.config.Config;
+import org.hypertrace.core.grpcutils.client.GrpcChannelRegistry;
+import org.hypertrace.core.serviceframework.spi.PlatformServiceLifecycle;
+
+public interface HttpContainerEnvironment {
+  GrpcChannelRegistry getChannelRegistry();
+
+  Config getConfig(String serviceName);
+
+  PlatformServiceLifecycle getLifecycle();
+}

platform-http-service-framework/src/main/java/org/hypertrace/core/serviceframework/http/HttpHandlerDefinition.java

@@ -0,0 +1,32 @@
+package org.hypertrace.core.serviceframework.http;
+
+import com.google.inject.Injector;
+import java.util.List;
+import javax.servlet.MultipartConfigElement;
+import javax.servlet.Servlet;
+import lombok.Builder;
+import lombok.Value;
+import lombok.experimental.Accessors;
+
+@Value
+@Builder
+public class HttpHandlerDefinition {
+  String name;
+  int port;
+  String contextPath;
+  Servlet servlet;
+  int maxHeaderSizeBytes;
+  CorsConfig corsConfig;
+  Injector injector;
+  MultipartConfigElement multipartConfig;
+
+  @Accessors(fluent = true)
+  boolean useSessions;
+
+  @Value
+  @Builder
+  public static class CorsConfig {
+    List<String> allowedHeaders;
+    List<String> allowedOrigins;
+  }
+}

platform-http-service-framework/src/main/java/org/hypertrace/core/serviceframework/http/HttpHandlerFactory.java

@@ -0,0 +1,8 @@
+package org.hypertrace.core.serviceframework.http;
+
+import java.util.List;
+
+@FunctionalInterface
+public interface HttpHandlerFactory {
+  List<HttpHandlerDefinition> buildHandlers(HttpContainerEnvironment containerEnvironment);
+}

platform-http-service-framework/src/main/java/org/hypertrace/core/serviceframework/http/ServerBuilder.java

@@ -0,0 +1,14 @@
+package org.hypertrace.core.serviceframework.http;
+
+import java.util.List;
+import java.util.concurrent.ExecutorService;
+
+public interface ServerBuilder<T extends ServerBuilder> {
+  T addHandler(HttpHandlerDefinition handlerDefinition);
+
+  T addHandlers(List<HttpHandlerDefinition> handlerDefinitions);
+
+  T setExecutor(ExecutorService executorService);
+
+  HttpContainer build();
+}

platform-http-service-framework/src/main/java/org/hypertrace/core/serviceframework/http/StandAloneHttpContainerEnvironment.java

@@ -0,0 +1,20 @@
+package org.hypertrace.core.serviceframework.http;
+
+import com.typesafe.config.Config;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import org.hypertrace.core.grpcutils.client.GrpcChannelRegistry;
+import org.hypertrace.core.serviceframework.config.ConfigClient;
+import org.hypertrace.core.serviceframework.spi.PlatformServiceLifecycle;
+
+@AllArgsConstructor
+public class StandAloneHttpContainerEnvironment implements HttpContainerEnvironment {
+  @Getter private final GrpcChannelRegistry channelRegistry;
+  @Getter private final PlatformServiceLifecycle lifecycle;
+  private final ConfigClient configClient;
+
+  @Override
+  public Config getConfig(String serviceName) {
+    return this.configClient.getConfig(serviceName, null, null, null);
+  }
+}

platform-http-service-framework/src/main/java/org/hypertrace/core/serviceframework/http/StandAloneHttpPlatformServiceContainer.java

@@ -0,0 +1,58 @@
+package org.hypertrace.core.serviceframework.http;
+
+import static io.grpc.Deadline.after;
+import static java.util.concurrent.TimeUnit.SECONDS;
+
+import java.util.List;
+import java.util.stream.Collectors;
+import lombok.extern.slf4j.Slf4j;
+import org.hypertrace.core.grpcutils.client.GrpcChannelRegistry;
+import org.hypertrace.core.serviceframework.PlatformService;
+import org.hypertrace.core.serviceframework.config.ConfigClient;
+import org.hypertrace.core.serviceframework.http.jetty.JettyHttpServerBuilder;
+
+@Slf4j
+public abstract class StandAloneHttpPlatformServiceContainer extends PlatformService {
+  private HttpContainer container;
+  private final GrpcChannelRegistry grpcChannelRegistry = new GrpcChannelRegistry();
+
+  public StandAloneHttpPlatformServiceContainer(ConfigClient config) {
+    super(config);
+  }
+
+  protected abstract List<HttpHandlerFactory> getHandlerFactories();
+
+  @Override
+  protected void doInit() {
+    this.container =
+        new JettyHttpServerBuilder().addHandlers(this.buildHandlerDefinitions()).build();
+  }
+
+  @Override
+  protected void doStart() {
+    log.info("Starting service {}", this.getServiceName());
+    this.container.start();
+    this.container.blockUntilStopped();
+  }
+
+  @Override
+  protected void doStop() {
+    log.info("Stopping service {}", this.getServiceName());
+    grpcChannelRegistry.shutdown(after(10, SECONDS));
+    this.container.stop();
+  }
+
+  @Override
+  public boolean healthCheck() {
+    return true;
+  }
+
+  private List<HttpHandlerDefinition> buildHandlerDefinitions() {
+    HttpContainerEnvironment environment =
+        new StandAloneHttpContainerEnvironment(
+            this.grpcChannelRegistry, this.getLifecycle(), this.configClient);
+    return this.getHandlerFactories().stream()
+        .flatMap(handlerFactory -> handlerFactory.buildHandlers(environment).stream())
+        .collect(Collectors.toUnmodifiableList());
+  }
+}

platform-http-service-framework/src/main/java/org/hypertrace/core/serviceframework/http/guice/SimpleGuiceServletContextListener.java

@@ -0,0 +1,15 @@
+package org.hypertrace.core.serviceframework.http.guice;
+
+import com.google.inject.Injector;
+import com.google.inject.servlet.GuiceServletContextListener;
+import lombok.RequiredArgsConstructor;
+
+@RequiredArgsConstructor
+public class SimpleGuiceServletContextListener extends GuiceServletContextListener {
+  private final Injector injector;
+
+  @Override
+  protected Injector getInjector() {
+    return injector;
+  }
+}

platform-http-service-framework/src/main/java/org/hypertrace/core/serviceframework/http/jetty/JettyHttpContainer.java

@@ -0,0 +1,46 @@
+package org.hypertrace.core.serviceframework.http.jetty;
+
+import static java.util.concurrent.TimeUnit.SECONDS;
+
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Future;
+import lombok.RequiredArgsConstructor;
+import lombok.SneakyThrows;
+import org.eclipse.jetty.server.Server;
+import org.hypertrace.core.serviceframework.http.HttpContainer;
+
+@RequiredArgsConstructor
+class JettyHttpContainer implements HttpContainer {
+  private final Server server;
+  private final ExecutorService executorService;
+  private Future<?> future;
+
+  @Override
+  public void start() {
+    this.future = this.executorService.submit(this::startAndWaitUnchecked);
+  }
+
+  @SneakyThrows
+  @Override
+  public void stop() {
+    this.executorService.shutdown();
+    this.executorService.awaitTermination(30, SECONDS);
+  }
+
+  @SneakyThrows
+  @Override
+  public void blockUntilStopped() {
+    this.future.get();
+  }
+
+  @Override
+  public boolean isStopped() {
+    return this.server.isStopped();
+  }
+
+  @SneakyThrows
+  private void startAndWaitUnchecked() {
+    this.server.start();
+    this.server.join();
+  }
+}