Connecting to Cloud SQL PostgreSQL from local java Webapp - postgresql

Question

I'm trying to connect to google cloud sql postgreSQL from my local web application, but I'm getting exception after executing:
DriverManager.getConnection(jdbcUrl, userName, password);
Exception:
2018-05-02 09:51:13.698:WARN:oejs.ServletHandler:qtp1720435669-17: Error for /LoginListener
java.lang.UnsatisfiedLinkError: The operation completed successfully.<|
at jnr.ffi.provider.jffi.AsmRuntime.newUnsatisifiedLinkError(AsmRuntime.java:40)
at jnr.unixsocket.Native$LibC$jnr$ffi$0.socket(Unknown Source)
at jnr.unixsocket.Native.socket(Native.java:92)
at jnr.unixsocket.UnixSocketChannel.<init>(UnixSocketChannel.java:101)
at jnr.unixsocket.UnixSocketChannel.open(UnixSocketChannel.java:65)
at com.google.cloud.sql.postgres.SocketFactory.createSocket(SocketFactory.java:66)
at org.postgresql.core.PGStream.<init>(PGStream.java:61)
at org.postgresql.core.v3.ConnectionFactoryImpl.openConnectionImpl(ConnectionFactoryImpl.java:156)
at org.postgresql.core.ConnectionFactory.openConnection(ConnectionFactory.java:49)
at org.postgresql.jdbc.PgConnection.<init>(PgConnection.java:195)
at org.postgresql.Driver.makeConnection(Driver.java:452)
at org.postgresql.Driver.connect(Driver.java:254)
at java.sql.DriverManager.getConnection(DriverManager.java:664)
at java.sql.DriverManager.getConnection(DriverManager.java:247)
at db.Connector.getConnection(Connector.java:31)
at dbMethods.SubscriberDBMethods.getSubscriber(SubscriberDBMethods.java:16)
at com.Admin101.LoginListener.doGet(LoginListener.java:49)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:687)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:848)
at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1772)
at com.google.appengine.tools.development.ResponseRewriterFilter.doFilter(ResponseRewriterFilter.java:134)
at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1759)
at com.google.appengine.tools.development.HeaderVerificationFilter.doFilter(HeaderVerificationFilter.java:34)
at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1759)
at com.google.appengine.api.blobstore.dev.ServeBlobFilter.doFilter(ServeBlobFilter.java:63)
at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1759)
at com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(TransactionCleanupFilter.java:48)
at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1759)
at com.google.appengine.tools.development.jetty9.StaticFileFilter.doFilter(StaticFileFilter.java:123)
at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1759)
at com.google.appengine.tools.development.DevAppServerModulesFilter.doDirectRequest(DevAppServerModulesFilter.java:366)
at com.google.appengine.tools.development.DevAppServerModulesFilter.doDirectModuleRequest(DevAppServerModulesFilter.java:349)
at com.google.appengine.tools.development.DevAppServerModulesFilter.doFilter(DevAppServerModulesFilter.java:116)
at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1759)
at com.google.appengine.tools.development.DevAppServerRequestLogFilter.doFilter(DevAppServerRequestLogFilter.java:44)
at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1751)
at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:582)
at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143)
at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:524)
at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:226)
at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1180)
at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:512)
at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185)
at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1112)
at com.google.appengine.tools.development.jetty9.DevAppEngineWebAppContext.doScope(DevAppEngineWebAppContext.java:94)
at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)
at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:134)
at com.google.appengine.tools.development.jetty9.JettyContainerService$ApiProxyHandler.handle(JettyContainerService.java:597)
at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:134)
at org.eclipse.jetty.server.Server.handle(Server.java:534)
at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:320)
at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:251)
at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:283)
at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:108)
at org.eclipse.jetty.io.SelectChannelEndPoint$2.run(SelectChannelEndPoint.java:93)
at org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.executeProduceConsume(ExecuteProduceConsume.java:303)
at org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.produceConsume(ExecuteProduceConsume.java:148)
at org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.run(ExecuteProduceConsume.java:136)
at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:671)
at org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:589)
at java.lang.Thread.run(Thread.java:748)
I've added dependency in the pom for postgresql.
<dependency>
<groupId>org.postgresql</groupId>
<artifactId>postgresql</artifactId>
<version>42.2.2</version>
</dependency>
<dependency>
<groupId>com.google.cloud.sql</groupId>
<artifactId>postgres-socket-factory</artifactId>
<version>1.0.8</version>
</dependency>
JDBC connection:
public static Connection getConnection()
{
Connection conn = null;
try
{ ApiProxy.Environment env = ApiProxy.getCurrentEnvironment();
Map<String,Object> attr = env.getAttributes();
String jdbcUrl = String.format(
"jdbc:postgresql://google/%s?socketFactory=com.google.cloud.sql.postgres.SocketFactory"
+ "&socketFactoryArg=%s",
DBNAME,
INSTANCE_NAME);
conn = DriverManager.getConnection(jdbcUrl, userName, password);
}
catch(Exception e)
{
e.printStackTrace();
}
return conn;
}
The same connection works fine if deployed to google app engine, but while running locally in appengine it throws the unsatisfiedLinkError.

Answer 1

In your JDBC connection code there is only one connection defined for a deployed application. Make sure that you have enabled PostreSQL Connector/J and add some code for local PostgreSQL connection. There are two similar related SO cases: this one and this one.
Check that `appengine-web.xml looks like:
<?xml version="1.0" encoding="utf-8"?>
<appengine-web-app xmlns="http://appengine.google.com/ns/1.0">
...
<use-google-connector-j>true</use-google-connector-j>
</appengine-web-app>
And use this MySQL snippet as example (adapt it to PostgreSQL and your URL):
if (SystemProperty.environment.value() == SystemProperty.Environment.Value.Production) {
// Load the class that provides the new "jdbc:google:mysql://" prefix.
Class.forName("com.mysql.jdbc.GoogleDriver");
url = "jdbc:google:mysql://your-project-id:your-instance-name/your-database?user=root";
} else {
// Local MySQL instance to use during development.
Class.forName("com.mysql.jdbc.Driver");
url = "jdbc:mysql://127.0.0.1:3306/your-database?user=root";
// Alternatively, connect to a Google Cloud SQL instance using:
// jdbc:mysql://ip-address-of-google-cloud-sql-instance:3306/your-database?user=root
}
Find related official documentation here.