Persisting a change in local.app.properties or database...

Support
#1

Hi,

I need to check, create and store a property at Application start (in applicationStarted()) - but I cannot write this to the database as the Persistence says there is no security context and I cannot save the change in local.app.properties as it does not persist pass a reboot.

Is there any easy way to do this ?

Many thanks

#2

OK, please can you close this question, as I have found a way to do what I need.

I needed to create/update an entity value from the applicationStarted function of my implementation of the AppContext.Listener class. The problem was with the entityManager, I could not ‘persist’ the change as there was no security context at this stage. To get round this, I create a sql statement and use the entityManager to create a native query and executeUpdate, i.e.


String query = "insert into MESSAGECENTER_M_C_CONFIG (ID, CREATED_BY, CRYPTO_KEY) values ('"
                             + UUID.randomUUID().toString() + "', 'System', 'ENC(sadjkjfhkasjhdkjahsdkjahd/asdsad==)'";
            try (Transaction transaction = persistence.createTransaction()) {
                EntityManager entityManager = persistence.getEntityManager();
                entityManager.createNativeQuery(query).executeUpdate();
                transaction.commit();
            }

Thanks

#3

To associate a security context with the current thread you can use the Authentication interface or the @Authenticated annotation.
An example of creating a user on the server startup:


package com.company.appstart;

import com.haulmont.cuba.core.Persistence;
import com.haulmont.cuba.core.Transaction;
import com.haulmont.cuba.core.TypedQuery;
import com.haulmont.cuba.core.global.Metadata;
import com.haulmont.cuba.core.global.PasswordEncryption;
import com.haulmont.cuba.core.sys.AppContext;
import com.haulmont.cuba.security.app.Authentication;
import com.haulmont.cuba.security.entity.Group;
import com.haulmont.cuba.security.entity.User;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;

import javax.annotation.PostConstruct;
import javax.inject.Inject;
import java.util.UUID;

@Component("app_Bootstrap")
public class Bootstrap implements AppContext.Listener {

    private Logger log = LoggerFactory.getLogger(getClass());

    @Inject
    private Persistence persistence;

    @Inject
    private Metadata metadata;

    @Inject
    private PasswordEncryption passwordEncryption;

    @Inject
    protected Authentication authentication;

    @PostConstruct
    public void init() {
        AppContext.addListener(this);
    }

    @Override
    public void applicationStarted() {
        log.info("Checking existence of the 'system' user");
        authentication.begin();
        try {
            try (Transaction tx = persistence.createTransaction()) {
                TypedQuery<User> query = persistence.getEntityManager().createQuery(
                        "select u from sec$User u where u.login = ?1", User.class);
                query.setParameter(1, "system");
                User user = query.getFirstResult();
                if (user == null) {
                    log.info("User 'system' does not exist, creating it");
                    user = metadata.create(User.class);
                    user.setLogin("system");
                    user.setPassword(passwordEncryption.getPasswordHash(user.getId(), "1"));
                    user.setGroup(persistence.getEntityManager().getReference(
                            Group.class, UUID.fromString("0fa2b1a5-1d68-4d69-9fbd-dff348347f93")));
                    persistence.getEntityManager().persist(user);
                } else {
                    log.info("User 'system' already exists");
                }
                tx.commit();
            }
        } finally {
            authentication.end();
        }
    }

    @Override
    public void applicationStopped() {
    }
}