feat: expose the number of times and the delay between each attempt D…

…HIS2 will try to connect to the database [DHIS2-16091] (#15485)

* feat: expose database "acquire connection retry attempts" through dhis2.conf

* chore: expose delay between each attempt

dhis-2/dhis-support/dhis-support-external/src/main/java/org/hisp/dhis/external/conf/ConfigurationKey.java

@@ -151,12 +151,36 @@ public enum ConfigurationKey {
    */
   CONNECTION_POOL_ACQUIRE_INCR("connection.pool.acquire_incr", "5", false),
 
+  /**
+   * Determines how many times the system will try to acquire a connection before giving up. If this
+   * value is less than or equal to zero, the system will keep trying indefinitely. (default: 30).
+   */
+  CONNECTION_POOL_ACQUIRE_RETRY_ATTEMPTS("connection.pool.acquire_retry_attempts", "30", false),
+
+  /**
+   * Determines the delay in milliseconds, c3p0 will wait between acquire attempts. (default: 1000)
+   */
+  CONNECTION_POOL_ACQUIRE_RETRY_DELAY("connection.pool.acquire_retry_delay", "1", false),
+
   /**
    * Determines how many connections at a time will try to acquire when the pool is exhausted.
    * (default: 5).
    */
   ANALYTICS_CONNECTION_POOL_ACQUIRE_INCR("analytics.connection.pool.acquire_incr", "5", false),
 
+  /**
+   * Determines how many times the system will try to acquire a connection before giving up. If this
+   * value is less than or equal to zero, the system will keep trying indefinitely. (default: 30).
+   */
+  ANALYTICS_CONNECTION_POOL_ACQUIRE_RETRY_ATTEMPTS(
+      "analytics.connection.pool.acquire_retry_attempts", "30", false),
+
+  /**
+   * Determines the delay in milliseconds, c3p0 will wait between acquire attempts. (default: 1000)
+   */
+  ANALYTICS_CONNECTION_POOL_ACQUIRE_RETRY_DELAY(
+      "analytics.connection.pool.acquire_retry_delay", "1", false),
+
   /**
    * Seconds a Connection can remain pooled but unused before being discarded. Zero means idle
    * connections never expire (default: 7200).

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

@@ -33,6 +33,8 @@
 import static org.hisp.dhis.external.conf.ConfigurationKey.ANALYTICS_CONNECTION_DRIVER_CLASS;
 import static org.hisp.dhis.external.conf.ConfigurationKey.ANALYTICS_CONNECTION_PASSWORD;
 import static org.hisp.dhis.external.conf.ConfigurationKey.ANALYTICS_CONNECTION_POOL_ACQUIRE_INCR;
+import static org.hisp.dhis.external.conf.ConfigurationKey.ANALYTICS_CONNECTION_POOL_ACQUIRE_RETRY_ATTEMPTS;
+import static org.hisp.dhis.external.conf.ConfigurationKey.ANALYTICS_CONNECTION_POOL_ACQUIRE_RETRY_DELAY;
 import static org.hisp.dhis.external.conf.ConfigurationKey.ANALYTICS_CONNECTION_POOL_IDLE_CON_TEST_PERIOD;
 import static org.hisp.dhis.external.conf.ConfigurationKey.ANALYTICS_CONNECTION_POOL_INITIAL_SIZE;
 import static org.hisp.dhis.external.conf.ConfigurationKey.ANALYTICS_CONNECTION_POOL_MAX_IDLE_TIME;
@@ -50,6 +52,8 @@
 import static org.hisp.dhis.external.conf.ConfigurationKey.CONNECTION_DRIVER_CLASS;
 import static org.hisp.dhis.external.conf.ConfigurationKey.CONNECTION_PASSWORD;
 import static org.hisp.dhis.external.conf.ConfigurationKey.CONNECTION_POOL_ACQUIRE_INCR;
+import static org.hisp.dhis.external.conf.ConfigurationKey.CONNECTION_POOL_ACQUIRE_RETRY_ATTEMPTS;
+import static org.hisp.dhis.external.conf.ConfigurationKey.CONNECTION_POOL_ACQUIRE_RETRY_DELAY;
 import static org.hisp.dhis.external.conf.ConfigurationKey.CONNECTION_POOL_IDLE_CON_TEST_PERIOD;
 import static org.hisp.dhis.external.conf.ConfigurationKey.CONNECTION_POOL_INITIAL_SIZE;
 import static org.hisp.dhis.external.conf.ConfigurationKey.CONNECTION_POOL_MAX_IDLE_TIME;
@@ -113,6 +117,10 @@ public enum ConfigKeyMapper {
             .put(CONNECTION_POOL_VALIDATION_TIMEOUT, ANALYTICS_CONNECTION_POOL_VALIDATION_TIMEOUT)
             /* C3P0-specific */
             .put(CONNECTION_POOL_ACQUIRE_INCR, ANALYTICS_CONNECTION_POOL_ACQUIRE_INCR)
+            .put(
+                CONNECTION_POOL_ACQUIRE_RETRY_ATTEMPTS,
+                ANALYTICS_CONNECTION_POOL_ACQUIRE_RETRY_ATTEMPTS)
+            .put(CONNECTION_POOL_ACQUIRE_RETRY_DELAY, ANALYTICS_CONNECTION_POOL_ACQUIRE_RETRY_DELAY)
             .put(CONNECTION_POOL_MAX_IDLE_TIME, ANALYTICS_CONNECTION_POOL_MAX_IDLE_TIME)
             .put(CONNECTION_POOL_MIN_SIZE, ANALYTICS_CONNECTION_POOL_MIN_SIZE)
             .put(CONNECTION_POOL_INITIAL_SIZE, ANALYTICS_CONNECTION_POOL_INITIAL_SIZE)
@@ -159,6 +167,9 @@ public static class PoolConfig {
 
     private String acquireIncrement;
 
+    private String acquireRetryAttempts;
+    private String acquireRetryDelay;
+
     private String maxIdleTime;
 
     private ConfigKeyMapper mapper;
@@ -271,6 +282,17 @@ private static DataSource createC3p0DbPool(PoolConfig config)
             firstNonNull(
                 config.getAcquireIncrement(),
                 dhisConfig.getProperty(mapper.getConfigKey(CONNECTION_POOL_ACQUIRE_INCR))));
+    final int acquireRetryAttempts =
+        parseInt(
+            firstNonNull(
+                config.getAcquireRetryAttempts(),
+                dhisConfig.getProperty(
+                    mapper.getConfigKey(CONNECTION_POOL_ACQUIRE_RETRY_ATTEMPTS))));
+    final int acquireRetryDelay =
+        parseInt(
+            firstNonNull(
+                config.getAcquireRetryDelay(),
+                dhisConfig.getProperty(mapper.getConfigKey(CONNECTION_POOL_ACQUIRE_RETRY_DELAY))));
     final int maxIdleTime =
         parseInt(
             firstNonNull(
@@ -304,6 +326,8 @@ private static DataSource createC3p0DbPool(PoolConfig config)
     dataSource.setMinPoolSize(minPoolSize);
     dataSource.setInitialPoolSize(initialSize);
     dataSource.setAcquireIncrement(acquireIncrement);
+    dataSource.setAcquireRetryAttempts(acquireRetryAttempts);
+    dataSource.setAcquireRetryDelay(acquireRetryDelay);
     dataSource.setMaxIdleTime(maxIdleTime);
     dataSource.setTestConnectionOnCheckin(testOnCheckIn);
     dataSource.setTestConnectionOnCheckout(testOnCheckOut);