Remove the experimental useLambdaCheck, opt for lambdaMode(true) instead

Where lambdaMode(true) just turns sets validateOnHeartbeat = false and
ultimately use validateStaleMillis

Author: rbygrave

ebean-datasource-api/src/main/java/io/ebean/datasource/DataSourceBuilder.java

@@ -710,7 +710,7 @@ default DataSourceBuilder initDatabaseForPlatform(String platform) {
    * check to detect when the function has been restored from suspension.
    */
   @Deprecated(since = "Experimental feature")
-  DataSourceBuilder useLambdaCheck(boolean useLambda);
+  DataSourceBuilder lambdaMode(boolean useLambda);
 
   /**
    * Load the settings from the properties with no prefix on the property names.
@@ -1008,11 +1008,5 @@ default String driverClassName() {
      * @return True to obtain a connection using ownerUsername and run InitDatabase.
      */
     boolean useInitDatabase();
-
-    /**
-     * Return true to enable the additional Lambda check (for old idle connections
-     * due to Lambda suspension).
-     */
-    boolean useLambdaCheck();
   }
 }

ebean-datasource-api/src/main/java/io/ebean/datasource/DataSourceConfig.java

@@ -80,7 +80,6 @@ public class DataSourceConfig implements DataSourceBuilder.Settings {
   private Properties clientInfo;
   private String applicationName;
   private boolean shutdownOnJvmExit;
-  private boolean useLambdaCheck;
   private boolean validateOnHeartbeat = true;
 
   @Override
@@ -132,7 +131,7 @@ public DataSourceConfig copy() {
     copy.offline = offline;
     copy.failOnStart = failOnStart;
     copy.shutdownOnJvmExit = shutdownOnJvmExit;
-    copy.useLambdaCheck = useLambdaCheck;
+    copy.validateOnHeartbeat = validateOnHeartbeat;
     if (customProperties != null) {
       copy.customProperties = new LinkedHashMap<>(customProperties);
     }
@@ -178,8 +177,8 @@ public DataSourceConfig setDefaults(DataSourceBuilder builder) {
     if (!shutdownOnJvmExit && other.isShutdownOnJvmExit()){
       shutdownOnJvmExit = true;
     }
-    if (!useLambdaCheck && other.useLambdaCheck()){
-      useLambdaCheck = true;
+    if (validateOnHeartbeat && !other.isValidateOnHeartbeat()){
+      validateOnHeartbeat = false;
     }
     if (customProperties == null) {
       var otherCustomProps = other.getCustomProperties();
@@ -717,17 +716,11 @@ public DataSourceConfig validateOnHeartbeat(boolean validateOnHeartbeat) {
   }
 
   @Override
-  public DataSourceBuilder useLambdaCheck(boolean useLambda) {
-    this.useLambdaCheck = useLambda;
+  public DataSourceBuilder lambdaMode(boolean useLambda) {
     this.validateOnHeartbeat = false;
     return this;
   }
 
-  @Override
-  public boolean useLambdaCheck() {
-    return useLambdaCheck;
-  }
-
   @Override
   public DataSourceConfig load(Properties properties) {
     return load(properties, null);
@@ -782,7 +775,6 @@ private void loadSettings(ConfigPropertiesHelper properties) {
     offline = properties.getBoolean("offline", offline);
     shutdownOnJvmExit = properties.getBoolean("shutdownOnJvmExit", shutdownOnJvmExit);
     validateOnHeartbeat = properties.getBoolean("validateOnHeartbeat", validateOnHeartbeat);
-    useLambdaCheck = properties.getBoolean("useLambdaCheck", useLambdaCheck);
 
     String isoLevel = properties.get("isolationLevel", _isolationLevel(isolationLevel));
     this.isolationLevel = _isolationLevel(isoLevel);

ebean-datasource-api/src/test/java/io/ebean/datasource/DataSourceConfigTest.java

@@ -136,20 +136,20 @@ public void defaults_someOverride() {
     assertThat(readOnly.getUsername()).isEqualTo("foo2");
     assertThat(readOnly.getMinConnections()).isEqualTo(3);
     assertThat(readOnly.isShutdownOnJvmExit()).isFalse();
-    assertThat(readOnly.useLambdaCheck()).isFalse();
+    assertThat(readOnly.isValidateOnHeartbeat()).isFalse();
   }
 
   @Test
   public void defaults_someOverride2() {
     DataSourceConfig readOnly = new DataSourceConfig();
     readOnly.setUrl("jdbc:postgresql://127.0.0.2:5432/unit");
 
-    DataSourceBuilder configBuilder = create().shutdownOnJvmExit(true).useLambdaCheck(true);
+    DataSourceBuilder configBuilder = create().shutdownOnJvmExit(true).lambdaMode(true);
     DataSourceConfig readOnly2 = readOnly.setDefaults(configBuilder);
 
     assertThat(readOnly2).isSameAs(readOnly);
     assertThat(readOnly.isShutdownOnJvmExit()).isTrue();
-    assertThat(readOnly.useLambdaCheck()).isTrue();
+    assertThat(readOnly.isValidateOnHeartbeat()).isTrue();
   }
 
   private DataSourceConfig create() {
@@ -171,7 +171,7 @@ public void loadSettings() throws IOException {
     assertConfigValues(config);
     assertThat(config.isShutdownOnJvmExit()).isTrue();
     assertThat(config.isValidateOnHeartbeat()).isTrue();
-    assertThat(config.useLambdaCheck()).isTrue();
+    assertThat(config.isValidateOnHeartbeat()).isTrue();
   }
 
   @Test
@@ -182,8 +182,7 @@ public void load_prefix() throws IOException {
     var config = new DataSourceConfig().load(props, "bar");
     assertConfigValues(config);
     assertThat(config.isShutdownOnJvmExit()).isFalse();
-    assertThat(config.useLambdaCheck()).isFalse();
-    assertThat(config.useLambdaCheck()).isFalse();
+    assertThat(config.isValidateOnHeartbeat()).isFalse();
   }
 
   @Test

ebean-datasource/src/main/java/io/ebean/datasource/pool/ConnectionPool.java

@@ -62,10 +62,8 @@ final class ConnectionPool implements DataSourcePool {
   private final Properties clientInfo;
   private final String applicationName;
   private final DataSource source;
-  private final int lambdaTrimMillis;
   private final boolean validateOnHeartbeat;
   private long nextTrimTime;
-  private long nextLambdaTrimTime;
 
   /**
    * HeartBeat checking will discover when it goes down, and comes back up again.
@@ -105,7 +103,6 @@ final class ConnectionPool implements DataSourcePool {
     this.initSql = params.getInitSql();
     this.transactionIsolation = params.getIsolationLevel();
     this.maxInactiveMillis = 1000 * params.getMaxInactiveTimeSecs();
-    this.lambdaTrimMillis = Math.max(maxInactiveMillis + 60_000, 300_000);
     this.maxAgeMillis = 60000L * params.getMaxAgeMinutes();
     this.leakTimeMinutes = params.getLeakTimeMinutes();
     this.captureStackTrace = params.isCaptureStackTrace();
@@ -131,7 +128,6 @@ final class ConnectionPool implements DataSourcePool {
       init();
     }
     this.nextTrimTime = System.currentTimeMillis() + trimPoolFreqMillis;
-    this.nextLambdaTrimTime = nextTrimTime + lambdaTrimMillis;
   }
 
   private void init() {
@@ -344,17 +340,6 @@ private void notifyUp() {
     }
   }
 
-  void checkLambdaIdle() {
-    if (System.currentTimeMillis() > nextLambdaTrimTime) {
-      // means that the usual background trimIdleConnections() has not been run recently
-      // which we interpret as a lambda being invoked after coming back from suspension
-      var timeGapSeconds = (System.currentTimeMillis() - nextTrimTime) / 1000;
-      var status = status(false);
-      Log.info("DataSource [{0}] lambda trim idle connections - timeGap {1}s {2}", name, timeGapSeconds, status);
-      trimIdleConnections();
-    }
-  }
-
   /**
    * Trim connections in the free list based on idle time and maximum age.
    */
@@ -363,7 +348,6 @@ private void trimIdleConnections() {
       try {
         queue.trim(maxInactiveMillis, maxAgeMillis);
         nextTrimTime = System.currentTimeMillis() + trimPoolFreqMillis;
-        nextLambdaTrimTime = nextTrimTime + lambdaTrimMillis;
       } catch (Exception e) {
         Log.error("Error trying to trim idle connections - message:" + e.getMessage(), e);
       }

ebean-datasource/src/main/java/io/ebean/datasource/pool/ConnectionPoolFactory.java

@@ -11,7 +11,6 @@ public final class ConnectionPoolFactory implements DataSourceFactory {
 
   @Override
   public DataSourcePool createPool(String name, DataSourceConfig config) {
-    var pool = new ConnectionPool(name, config);
-    return config.useLambdaCheck() ? new LambdaPool(pool) : pool;
+    return new ConnectionPool(name, config);
   }
 }

ebean-datasource/src/main/java/io/ebean/datasource/pool/LambdaPool.java

@@ -40,12 +40,10 @@ void createPool_forLambda() throws Exception {
       .url("jdbc:h2:mem:factory2")
       .username("sa")
       .password("")
-      .useLambdaCheck(true)
+      .lambdaMode(true)
       // .trimPoolFreqSecs(-1) // stop the heartbeat and reduce LAMBDA_MILLIS to 1100
       .build();
 
-    assertThat(pool).isInstanceOf(LambdaPool.class);
-
     try (Connection connection = pool.getConnection()) {
       try (PreparedStatement stmt = connection.prepareStatement("create table junk (acol varchar(10))")) {
         stmt.execute();