Ice4j v2.0.0 hangs while checking AWS EC2

[cmeng-git]

Trying to integrate using ice4j-2.0.0 release into aTalk with all the default settings, but facing problem with the following AwsCandidateHarvester#doTestEc2 in conn.getContent. The system just hangs in this execution without return. It seems that EC2_TEST_URL (http://169.254.169.254/latest/meta-data/) is not reachable.

    /**
     * Tries to connect to an Amazon EC2-specific URL in order to determine
     * whether we are running on EC2.
     *
     * @return <tt>true</tt> if the connection succeeded, <tt>false</tt>
     * otherwise.
     */
    private static boolean doTestEc2()
    {
        try
        {
            URLConnection conn = new URL(EC2_TEST_URL).openConnection();
            conn.setConnectTimeout(500); //don't hang for too long
            conn.getContent();

            return true;
        }
        catch(Exception exc)
        {
            //ah! I knew you weren't one of those ...
            return false;
        }
    }

[damencho]

You can disable aws harvester using org.ice4j.ice.harvest.DISABLE_AWS_HARVESTER system property.

[cmeng-git]

Yes, actually I already did that, and it works. But isn't that the system should not hangs even with the option disabled, at least it should auto exit on timeout?

[damencho]

I havn't heard of such reports for jvb where this is not disabled. You can check the usage of ice4j there, I suppose it is in new thread or something.

[bgrozev]

Does it block for more than 500ms?

[cmeng-git]

When the option is enabled, it does not return upon executed conn.getContent() or throw exception even after a long wait; although it seems to have set a 500mS timeout on connection.
By the way it aTalk is an android application. No sure if it makes a different when running on other OS.
I did a ping on Ubuntu to 169.254.169.254, look like the address is not reachable.

[bgrozev]

Thanks for reporting. By design it should timeout after 500ms.

[ibauersachs]

Try to set conn.setReadTimeout as well, or use the system properties for debugging:

System.setProperty("sun.net.client.defaultConnectTimeout", "500");
System.setProperty("sun.net.client.defaultReadTimeout", "500");

But note that the API states that non-standard implementations might ignore the timeouts.

[cmeng-git]

The above two timer settings do not work for android aTalk. It seems that it requires java 1.8 and is not available in android OS.