Bind PostgresKVStore as default, add HikariCp connection pooling defa…

…ult config

app/build.gradle

@@ -4,6 +4,7 @@ buildscript {
   ext.protobufVersion = '3.21.7'
   ext.jerseyVersion = '3.1.0'
   ext.junitVersion = '5.9.0'
+  ext.mockitoVersion = '5.2.0'
   ext.postgresVersion = '42.5.1'
   ext.jooqVersion = '3.17.7'
   ext.guiceVersion = '5.1.0'
@@ -42,17 +43,23 @@ dependencies {
   implementation "org.jooq:jooq-codegen:$jooqVersion"
   runtimeOnly "org.postgresql:postgresql:$postgresVersion"
   jooqGenerator "org.postgresql:postgresql:$postgresVersion"
+  implementation 'com.zaxxer:HikariCP:5.0.1' // Connection pooling for postgres/jdbc
 
   implementation "com.google.inject:guice:$guiceVersion"
   implementation "org.glassfish.hk2:guice-bridge:3.0.3"
 
   compileOnly 'org.projectlombok:lombok:1.18.24'
   annotationProcessor 'org.projectlombok:lombok:1.18.24'
 
+  implementation('org.glassfish.jersey.inject:jersey-hk2:3.1.0')
+  implementation "org.glassfish.hk2:guice-bridge:3.0.3"
+
   compileOnly 'org.projectlombok:lombok:1.18.24'
   annotationProcessor 'org.projectlombok:lombok:1.18.24'
 
   testImplementation "org.junit.jupiter:junit-jupiter-api:$junitVersion"
+  testImplementation "org.junit.jupiter:junit-jupiter-params:$junitVersion"
+  testImplementation "org.mockito:mockito-core:$mockitoVersion"
   testRuntimeOnly "org.junit.jupiter:junit-jupiter-engine:$junitVersion"
   testImplementation "org.hamcrest:hamcrest-library:2.2"
   testImplementation "org.testcontainers:junit-jupiter:1.17.6"

app/src/main/java/org/vss/guice/BaseModule.java

@@ -1,13 +1,74 @@
 package org.vss.guice;
 
 import com.google.inject.AbstractModule;
+import com.google.inject.Provides;
 import com.google.inject.Singleton;
+import com.zaxxer.hikari.HikariConfig;
+import com.zaxxer.hikari.HikariDataSource;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.Properties;
+import org.jooq.DSLContext;
+import org.jooq.SQLDialect;
+import org.jooq.impl.DSL;
 import org.vss.KVStore;
 import org.vss.impl.postgres.PostgresBackendImpl;
 
 public class BaseModule extends AbstractModule {
+
   @Override
   protected void configure() {
     bind(KVStore.class).to(PostgresBackendImpl.class).in(Singleton.class);
   }
+
+  @Provides
+  @Singleton
+  public DSLContext provideDSLContext() throws ClassNotFoundException {
+    // Required to load postgres drivers in tomcat
+    Class.forName("org.postgresql.Driver");
+    return DSL.using(HikariCPDataSource.dataSource, SQLDialect.POSTGRES);
+  }
+}
+
+class HikariCPDataSource {
+
+  private static HikariConfig config = new HikariConfig();
+  public static HikariDataSource dataSource;
+
+  static {
+    try (InputStream input = HikariCPDataSource.class.getClassLoader()
+        .getResourceAsStream("hikariJdbc.properties")) {
+      Properties hikariJdbcProperties = new Properties();
+      hikariJdbcProperties.load(input);
+
+      config.setJdbcUrl(hikariJdbcProperties.getProperty("jdbc.url"));
+      config.setUsername(hikariJdbcProperties.getProperty("jdbc.username"));
+      config.setPassword(hikariJdbcProperties.getProperty("jdbc.password"));
+
+      config.setMaximumPoolSize(
+          Integer.parseInt(hikariJdbcProperties.getProperty("hikaricp.maxPoolSize")));
+      config.setMinimumIdle(
+          Integer.parseInt(hikariJdbcProperties.getProperty("hikaricp.minimumIdle")));
+      config.setConnectionTimeout(
+          Long.parseLong(hikariJdbcProperties.getProperty("hikaricp.connectionTimeout")));
+      config.setIdleTimeout(
+          Long.parseLong(hikariJdbcProperties.getProperty("hikaricp.idleTimeout")));
+      config.setMaxLifetime(
+          Long.parseLong(hikariJdbcProperties.getProperty("hikaricp.maxLifetime")));
+
+      config.addDataSourceProperty("cachePrepStmts",
+          hikariJdbcProperties.getProperty("hikaricp.cachePrepStmts"));
+      config.addDataSourceProperty("prepStmtCacheSize",
+          hikariJdbcProperties.getProperty("hikaricp.prepStmtCacheSize"));
+      config.addDataSourceProperty("prepStmtCacheSqlLimit",
+          hikariJdbcProperties.getProperty("hikaricp.prepStmtCacheSqlLimit"));
+
+      dataSource = new HikariDataSource(config);
+    } catch (IOException e) {
+      throw new RuntimeException("Unable to read hikariJdbcProperties from resources");
+    }
+  }
+
+  private HikariCPDataSource() {
+  }
 }

app/src/main/resources/hikariJdbc.properties

@@ -0,0 +1,23 @@
+# Default properties, these are meant to be changed according to application needs.
+
+jdbc.url=jdbc:postgresql://localhost:5432/postgres
+jdbc.username=postgres
+jdbc.password=
+
+# Idle Timeout
+hikaricp.minimumIdle=10
+
+# Set connectionTimeout to 30 secs
+hikaricp.connectionTimeout=30000
+
+# Set idle timeout to 10 minutes
+hikaricp.idleTimeout=600000
+
+# Set Maximum lifetime of a connection to 30minutes
+hikaricp.maxLifetime=1800000
+
+# Performance Optimizations
+hikaricp.maxPoolSize=50
+hikaricp.cachePrepStmts=true
+hikaricp.prepStmtCacheSize=250
+hikaricp.prepStmtCacheSqlLimit=2048