@Test
    void load_balancers_can_be_set() throws IOException, SAXException {
        // No endpoints
        verifyAllowedUrns("", Environment.prod, "eu", ZoneEndpoint.defaultEndpoint);

        // No non-default settings
        verifyAllowedUrns("""
                          <endpoint type='zone' container-id='default' />
                          """,
                          Environment.prod,
                          "eu",
                          ZoneEndpoint.defaultEndpoint);

        // No allowed urns
        verifyAllowedUrns("""
                          <endpoint type='private' container-id='default' />
                          """,
                          Environment.prod,
                          "eu",
                          new ZoneEndpoint(true, true, List.of()));

        // Various settings
        verifyAllowedUrns("""
                          <endpoint type='zone' container-id='default' enabled='false' />
                          <endpoint type='private' container-id='default'>
                            <region>eu</region>
                            <allow with='aws-private-link' arn='barn' />
                            <allow with='gcp-service-connect' project='nine' />
                          </endpoint>
                          """,
                          Environment.prod,
                          "eu",
                          new ZoneEndpoint(false, true, List.of(new AllowedUrn(AccessType.awsPrivateLink, "barn"),
                                                                new AllowedUrn(AccessType.gcpServiceConnect, "nine"))));

        // Various settings, but wrong region
        verifyAllowedUrns("""
                          <endpoint type='zone' container-id='default' enabled='false' />
                          <endpoint type='private' container-id='default'>
                            <region>eu</region>
                            <allow with='aws-private-link' arn='barn' />
                            <allow with='gcp-service-connect' project='nine' />
                          </endpoint>
                          """,
                          Environment.prod,
                          "us",
                          ZoneEndpoint.defaultEndpoint);

        // Various settings, but wrong environment
        verifyAllowedUrns("""
                          <endpoint type='zone' container-id='default' enabled='false' />
                          <endpoint type='private' container-id='default'>
                            <region>eu</region>
                            <allow with='aws-private-link' arn='barn' />
                            <allow with='gcp-service-connect' project='nine' />
                          </endpoint>
                          """,
                          Environment.dev,
                          "eu",
                          ZoneEndpoint.defaultEndpoint);
    }
Tests for "core functionality" of the container model, e.g. ports, or the 'components' and 'bundles' configs.

Before adding a new test to this class, check if the test fits into one of the other existing subclasses
of {@link ContainerModelBuilderTestBase}. If not, consider creating a new subclass.

@author gjoranv
config-model/src/test/java/com/yahoo/vespa/model/container/xml/ContainerModelBuilderTest.java