fix: Read replica database config not detected [DHIS2-15963] [2.39]

dhis-2/dhis-support/dhis-support-hibernate/src/main/java/org/hisp/dhis/config/DataSourceConfig.java

@@ -44,7 +44,7 @@
 import org.hisp.dhis.common.CodeGenerator;
 import org.hisp.dhis.commons.util.DebugUtils;
 import org.hisp.dhis.datasource.DatabasePoolUtils;
-import org.hisp.dhis.datasource.DefaultReadOnlyDataSourceManager;
+import org.hisp.dhis.datasource.ReadOnlyDataSourceManager;
 import org.hisp.dhis.external.conf.ConfigurationKey;
 import org.hisp.dhis.external.conf.DhisConfigurationProvider;
 import org.hisp.dhis.hibernate.HibernateConfigurationProvider;
@@ -93,7 +93,7 @@ public JdbcTemplate executionPlanJdbcTemplate(@Qualifier("dataSource") DataSourc
   @Bean("readOnlyJdbcTemplate")
   @DependsOn("dataSource")
   public JdbcTemplate readOnlyJdbcTemplate(@Qualifier("dataSource") DataSource dataSource) {
-    DefaultReadOnlyDataSourceManager manager = new DefaultReadOnlyDataSourceManager(dhisConfig);
+    ReadOnlyDataSourceManager manager = new ReadOnlyDataSourceManager(dhisConfig);
 
     JdbcTemplate jdbcTemplate =
         new JdbcTemplate(MoreObjects.firstNonNull(manager.getReadOnlyDataSource(), dataSource));

dhis-2/dhis-support/dhis-support-hibernate/src/main/java/org/hisp/dhis/datasource/ReadOnlyDataSourceManager.java

@@ -27,26 +27,134 @@
  */
 package org.hisp.dhis.datasource;
 
+import static com.google.common.base.Preconditions.checkNotNull;
+import static org.hisp.dhis.external.conf.ConfigurationKey.CONNECTION_PASSWORD;
+import static org.hisp.dhis.external.conf.ConfigurationKey.CONNECTION_URL;
+import static org.hisp.dhis.external.conf.ConfigurationKey.CONNECTION_USERNAME;
+
+import java.beans.PropertyVetoException;
+import java.sql.SQLException;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Properties;
 import javax.sql.DataSource;
+import lombok.extern.slf4j.Slf4j;
+import org.apache.commons.lang3.StringUtils;
+import org.hisp.dhis.commons.util.DebugUtils;
+import org.hisp.dhis.external.conf.ConfigurationKey;
+import org.hisp.dhis.external.conf.DhisConfigurationProvider;
+import org.hisp.dhis.util.ObjectUtils;
 
 /**
  * @author Lars Helge Overland
  */
-public interface ReadOnlyDataSourceManager {
-  /**
-   * Returns a data source which should be used for read only queries only. If read only replicas
-   * have been explicitly defined in the configuration, the data source implementation will be
-   * routing to potentially multiple underlying data sources. If not, the data source will point to
-   * the main data source.
-   *
-   * @return a DataSource instance.
-   */
-  DataSource getReadOnlyDataSource();
-
-  /**
-   * Returns the number of explicitly defined read only database instances.
-   *
-   * @return the number of explicitly defined read only database instances.
-   */
-  int getReadReplicaCount();
+@Slf4j
+public class ReadOnlyDataSourceManager {
+  private static final String FORMAT_READ_PREFIX = "read%d.";
+
+  private static final String FORMAT_CONNECTION_URL = FORMAT_READ_PREFIX + CONNECTION_URL.getKey();
+
+  private static final String FORMAT_CONNECTION_USERNAME =
+      FORMAT_READ_PREFIX + CONNECTION_USERNAME.getKey();
+
+  private static final String FORMAT_CONNECTION_PASSWORD =
+      FORMAT_READ_PREFIX + CONNECTION_PASSWORD.getKey();
+
+  private static final int VAL_ACQUIRE_INCREMENT = 6;
+
+  private static final int VAL_MAX_IDLE_TIME = 21600;
+
+  private static final int MAX_READ_REPLICAS = 5;
+
+  public ReadOnlyDataSourceManager(DhisConfigurationProvider config) {
+    checkNotNull(config);
+    init(config);
+  }
+
+  /** State holder for the resolved read only data source. */
+  private DataSource internalReadOnlyDataSource;
+
+  /** State holder for explicitly defined read only data sources. */
+  private List<DataSource> internalReadOnlyInstanceList;
+
+  public void init(DhisConfigurationProvider config) {
+    List<DataSource> ds = getReadOnlyDataSources(config);
+
+    this.internalReadOnlyInstanceList = ds;
+    this.internalReadOnlyDataSource = !ds.isEmpty() ? new CircularRoutingDataSource(ds) : null;
+  }
+
+  // -------------------------------------------------------------------------
+  // DataSourceManager implementation
+  // -------------------------------------------------------------------------
+
+  public DataSource getReadOnlyDataSource() {
+    return internalReadOnlyDataSource;
+  }
+
+  public int getReadReplicaCount() {
+    return internalReadOnlyInstanceList != null ? internalReadOnlyInstanceList.size() : 0;
+  }
+
+  // -------------------------------------------------------------------------
+  // Supportive methods
+  // -------------------------------------------------------------------------
+
+  private List<DataSource> getReadOnlyDataSources(DhisConfigurationProvider config) {
+    String mainUser = config.getProperty(ConfigurationKey.CONNECTION_USERNAME);
+    String mainPassword = config.getProperty(ConfigurationKey.CONNECTION_PASSWORD);
+    String driverClass = config.getProperty(ConfigurationKey.CONNECTION_DRIVER_CLASS);
+    String maxPoolSize = config.getProperty(ConfigurationKey.CONNECTION_POOL_MAX_SIZE);
+    String dbPoolType = config.getProperty(ConfigurationKey.DB_POOL_TYPE);
+
+    Properties props = config.getProperties();
+
+    List<DataSource> dataSources = new ArrayList<>();
+
+    for (int i = 1; i <= MAX_READ_REPLICAS; i++) {
+      String jdbcUrl = props.getProperty(String.format(FORMAT_CONNECTION_URL, i));
+      String username = props.getProperty(String.format(FORMAT_CONNECTION_USERNAME, i));
+      String password = props.getProperty(String.format(FORMAT_CONNECTION_PASSWORD, i));
+
+      username = StringUtils.defaultIfEmpty(username, mainUser);
+      password = StringUtils.defaultIfEmpty(password, mainPassword);
+
+      DatabasePoolUtils.PoolConfig.PoolConfigBuilder builder =
+          DatabasePoolUtils.PoolConfig.builder();
+      builder.dhisConfig(config);
+      builder.password(password);
+      builder.username(username);
+      builder.jdbcUrl(jdbcUrl);
+      builder.dbPoolType(dbPoolType);
+      builder.maxPoolSize(maxPoolSize);
+      builder.acquireIncrement(String.valueOf(VAL_ACQUIRE_INCREMENT));
+      builder.maxIdleTime(String.valueOf(VAL_MAX_IDLE_TIME));
+
+      if (ObjectUtils.allNonNull(jdbcUrl, username, password)) {
+        try {
+          dataSources.add(DatabasePoolUtils.createDbPool(builder.build()));
+        } catch (SQLException | PropertyVetoException e) {
+          String message =
+              String.format(
+                  "Connection test failed for read replica database pool, "
+                      + "driver class: '%s', URL: '%s', user: '%s'",
+                  driverClass, jdbcUrl, username);
+
+          log.error(message);
+          log.error(DebugUtils.getStackTrace(e));
+
+          throw new IllegalStateException(message, e);
+        }
+      }
+    }
+
+    log.info("Read only configuration initialized, read replicas found: " + dataSources.size());
+
+    config
+        .getProperties()
+        .setProperty(
+            ConfigurationKey.ACTIVE_READ_REPLICAS.getKey(), String.valueOf(dataSources.size()));
+
+    return dataSources;
+  }
 }