fix: connection pool test and idle configs (#183)

* fix: connection pool test

* fix: version update

* fix: tests

* fix: backport more changes

* fix: backport

* Update src/main/java/io/supertokens/storage/postgresql/ConnectionPool.java

---------

Co-authored-by: Rishabh Poddar <[email protected]>

Author: sattvikc

CHANGELOG.md

@@ -7,6 +7,11 @@ to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
 
+## [4.0.3] - 2024-02-07
+
+- Adds tests to check connection pool behaviour.
+- Adds `postgresql_idle_connection_timeout` and `postgresql_minimum_idle_connections` configs to control active connections to the database.
+
 ## [4.0.2]
 
 - Fixes null pointer issue when user belongs to no tenant.

build.gradle

@@ -2,7 +2,7 @@ plugins {
     id 'java-library'
 }
 
-version = "4.0.2"
+version = "4.0.3"
 
 repositories {
     mavenCentral()

config.yaml

@@ -67,3 +67,11 @@ postgresql_config_version: 0
 # (DIFFERENT_ACROSS_TENANTS | OPTIONAL | Default: "thirdparty_users") string value. Specify the name of the table
 # that will store the thirdparty recipe users.
 # postgresql_thirdparty_users_table_name
+
+# (DIFFERENT_ACROSS_TENANTS | OPTIONAL | Default: 60000) long value. Timeout in milliseconds for the idle connections
+# to be closed.
+# postgresql_idle_connection_timeout:
+
+# (DIFFERENT_ACROSS_TENANTS | OPTIONAL | Default: null) integer value. Minimum number of idle connections to be kept
+# active. If not set, minimum idle connections will be same as the connection pool size.
+# postgresql_minimum_idle_connections:

devConfig.yaml

@@ -69,3 +69,11 @@ postgresql_password: "root"
 # (DIFFERENT_ACROSS_TENANTS | OPTIONAL | Default: "thirdparty_users") string value. Specify the name of the table
 # that will store the thirdparty recipe users.
 # postgresql_thirdparty_users_table_name
+
+# (DIFFERENT_ACROSS_TENANTS | OPTIONAL | Default: 60000) long value. Timeout in milliseconds for the idle connections
+# to be closed.
+# postgresql_idle_connection_timeout:
+
+# (DIFFERENT_ACROSS_TENANTS | OPTIONAL | Default: null) integer value. Minimum number of idle connections to be kept
+# active. If not set, minimum idle connections will be same as the connection pool size.
+# postgresql_minimum_idle_connections:

src/main/java/io/supertokens/storage/postgresql/ConnectionPool.java

@@ -81,6 +81,10 @@ private synchronized void initialiseHikariDataSource() throws SQLException {
         }
         config.setMaximumPoolSize(userConfig.getConnectionPoolSize());
         config.setConnectionTimeout(5000);
+        if (userConfig.getMinimumIdleConnections() != null) {
+            config.setMinimumIdle(userConfig.getMinimumIdleConnections());
+            config.setIdleTimeout(userConfig.getIdleConnectionTimeout());
+        }
         config.addDataSourceProperty("cachePrepStmts", "true");
         config.addDataSourceProperty("prepStmtCacheSize", "250");
         config.addDataSourceProperty("prepStmtCacheSqlLimit", "2048");

src/main/java/io/supertokens/storage/postgresql/Start.java

@@ -100,6 +100,8 @@
 import java.sql.SQLTransactionRollbackException;
 import java.util.*;
 
+import static io.supertokens.storage.postgresql.QueryExecutorTemplate.execute;
+
 public class Start
         implements SessionSQLStorage, EmailPasswordSQLStorage, EmailVerificationSQLStorage, ThirdPartySQLStorage,
         JWTRecipeSQLStorage, PasswordlessSQLStorage, UserMetadataSQLStorage, UserRolesSQLStorage, UserIdMappingStorage,
@@ -109,7 +111,8 @@ public class Start
     // SaaS. If the core is not running in SuperTokens SaaS, this array has no effect.
     private static String[] PROTECTED_DB_CONFIG = new String[]{"postgresql_connection_pool_size",
             "postgresql_connection_uri", "postgresql_host", "postgresql_port", "postgresql_user", "postgresql_password",
-            "postgresql_database_name", "postgresql_table_schema"};
+            "postgresql_database_name", "postgresql_table_schema", "postgresql_idle_connection_timeout",
+            "postgresql_minimum_idle_connections"};
     private static final Object appenderLock = new Object();
     public static boolean silent = false;
     private ResourceDistributor resourceDistributor = new ResourceDistributor();
@@ -2819,4 +2822,17 @@ public String[] getAllTablesInTheDatabaseThatHasDataForAppId(String appId) throw
     public Thread getMainThread() {
         return mainThread;
     }
+
+    @TestOnly
+    public int getDbActivityCount(String dbname) throws SQLException, StorageQueryException {
+        String QUERY = "SELECT COUNT(*) as c FROM pg_stat_activity WHERE datname = ?;";
+        return execute(this, QUERY, pst -> {
+            pst.setString(1, dbname);
+        }, result -> {
+            if (result.next()) {
+                return result.getInt("c");
+            }
+            return -1;
+        });
+    }
 }

src/main/java/io/supertokens/storage/postgresql/config/PostgreSQLConfig.java

@@ -112,6 +112,14 @@ public class PostgreSQLConfig {
     @ConnectionPoolProperty
     private String postgresql_connection_scheme = "postgresql";
 
+    @JsonProperty
+    @ConnectionPoolProperty
+    private long postgresql_idle_connection_timeout = 60000;
+
+    @JsonProperty
+    @ConnectionPoolProperty
+    private Integer postgresql_minimum_idle_connections = null;
+
     @IgnoreForAnnotationCheck
     boolean isValidAndNormalised = false;
 
@@ -234,6 +242,14 @@ public String getThirdPartyUsersTable() {
         return postgresql_thirdparty_users_table_name;
     }
 
+    public long getIdleConnectionTimeout() {
+        return postgresql_idle_connection_timeout;
+    }
+
+    public Integer getMinimumIdleConnections() {
+        return postgresql_minimum_idle_connections;
+    }
+
     public String getThirdPartyUserToTenantTable() {
         return addSchemaAndPrefixToTableName("thirdparty_user_to_tenant");
     }
@@ -340,6 +356,20 @@ public void validateAndNormalise() throws InvalidConfigException {
                     "'postgresql_connection_pool_size' in the config.yaml file must be > 0");
         }
 
+        if (postgresql_minimum_idle_connections != null) {
+            if (postgresql_minimum_idle_connections < 0) {
+                throw new InvalidConfigException(
+                        "'postgresql_minimum_idle_connections' must be >= 0");
+            }
+
+            if (postgresql_minimum_idle_connections > postgresql_connection_pool_size) {
+                throw new InvalidConfigException(
+                        "'postgresql_minimum_idle_connections' must be less than or equal to "
+                                + "'postgresql_connection_pool_size'");
+            }
+        }
+
+
         // Normalisation
         if (postgresql_connection_uri != null) {
             { // postgresql_connection_attributes