I have a Jhipster monolithic application. I removed Liquibase and I want to use data.sql file to insert initial data. I created a data.sql and data-h2.sql which contain insert scripts. They are located under src/main/resources. But none of the data seems to be inserted.
How can I use data.sql to insert data during startup, without using Liquibase?
Commenting spring.datasource.type property and adding spring.jpa.hibernate.create-drop property helped resolve this issue. I think some jhipster configuration overrides default spring-boot configuration.
Here is how I come up with this solution:
While debugging DataSourceInitializedPublisher.publishEventIfRequired, I saw that following line returned a null reference:
private void publishEventIfRequired(EntityManagerFactory entityManagerFactory) {
DataSource dataSource = findDataSource(entityManagerFactory);
...
}
I commented spring.datasource.type property in application-dev.yml. In this way, spring switched to tomcat connection pool automatically.
Then, I found out that DataSourceInitializedPublisher.isInitializingDatabase required spring.jpa.hibernate.hbm2ddl.auto property to be defined in configuration:
private boolean isInitializingDatabase(DataSource dataSource) {
...
if (hibernate.containsKey("hibernate.hbm2ddl.auto")) {
return true;
}
return false;
}
After adding the missing property, spring-boot started to execute data.sql file.
Update
For those who want to execute a platform specific data.sql file, such as data-h2.sql, you should also add following property:
spring.datasource.platform=h2
Update
For those who need to convert default Jhipster data stored in csv files into sql format, you may refer to following gist:
https://gist.github.com/hkarakose/cf7f1b5b241dad611ba01c0211f42108
Related
I got to know Java spring JPA a couple days ago and there is one question which really makes me confused.
As I create a repository and use 'save()' method to save some objects into it. How does it know what type of database I am using and which local location to save.
I know I can config database (h2) like:
spring.datasource.url=jdbc:h2:mem/mydb
Then JPA will know: ok you are using h2 database and url is "jdbc:h2:mem/mydb"
However, some people said this config is not mandatory. If without this config, how does JPA knows which database I gonna use?
From the spring-boot documentation:
You should at least specify the URL by setting the spring.datasource.url property. Otherwise, Spring Boot tries to auto-configure an embedded database.
The following class is responsible for providing default settings for embedded DB: org.springframework.boot.autoconfigure.jdbc.DataSourceProperties
public String determineDatabaseName() {
...
if (this.embeddedDatabaseConnection != EmbeddedDatabaseConnection.NONE) {
return "testdb";
}
...
}
This answer can also be helpful: Where does the default datasource url for h2 come from on Spring Boot?
Application.properties
spring.datasource.url=
spring.datasource.username=
spring.datasource.password=
spring.datasource.driver-class-name=
i placed this application.properties in resources folder.
Java Class
#Component
public class data{
#Autowired
private JdbcTemplate jdbcTemplate;
public void queryData(){
String sql = "select * from DEPOSIT";
jdbcTemplate = new JdbcTemplate();
jdbcTemplate.execute(sql);
}
}
I am getting
java.lang.Illegal Argument Exception:No Data Source Specified
I am getting this error message even though i specified data source in application.properties
I am using Spring Boot for this task. I Have added almost all the dependencies required in POM.
Not sure why i am not able to access data source. basically trying to access data from DB using Spring boot, MySQL, jdbcTemplate.
Not sure whats wrong here.
Do i have to add anything in the code so that data source can be specified in java class?
Add below properties to your application.properties file. This specifies the data source for your application. Do check if mysql is running on your machine before starting your application.
spring.jpa.hibernate.ddl-auto=update
spring.datasource.url=jdbc:mysql://localhost:3306/db
spring.datasource.username=yourusername
spring.datasource.password=yourpassword
For additional information refer to below link:
https://docs.spring.io/spring-boot/docs/current/reference/html/boot-features-sql.html
i'm using spring and at the moment running my tests create new objects in my "real" embedded database. I want to create a new one or a temporary db just for testing. I'm new with spring and neo4j so could anyone please help?
thanks a lot
If you are using the embedded driver with SDN/OGM you just need to configure it without providing a path. Then it will create embedded database in /tmp/.. which gets deleted on jvm exit.
E.g. if you are using java configuration
#Bean
public Configuration getConfiguration() {
Configuration config = new Configuration();
config
.driverConfiguration()
.setDriverClassName("org.neo4j.ogm.drivers.embedded.driver.EmbeddedDriver");
return config;
}
See docs for full documentation
http://docs.spring.io/spring-data/data-neo4j/docs/current/reference/html/#_configuring_the_embedded_driver
I am trying to use flyway for DB migrations and Spring boot's flyway support for auto-upgrading DB upon application start-up and subsequently this database will be used by my JPA layer
However this requires that schema be present in the DB so that primary datasource initialization is successful. What are the options available to run a SQL script that will create the required schema before flyway migrations happen.
Note that If I use flyway gradle plugin (and give the URL as jdbc:mysql://localhost/mysql. It does create the schema for me. Am wondering if I could make this happen from Java code on application startup.
Flyway does not support full installation when schema is empty, just migration-by-migration execution.
You could though add schema/user creation scripts in the first migration, though then your migration scripts need to be executed with sysdba/root/admin user and you need to set current schema at the beginning of each migration.
If using Flyway, the least problematic way is to install schema for the first time manually and do a baseline Flyway task (also manually). Then you are ready for next migrations to be done automatically.
Although Flyway is a great tool for database migrations it does not cover this particular use case well (installing schema for the first time).
"Am wondering if I could make this happen from Java code on application startup."
The simple answer is yes as Flyway supports programmatic configuration from with java applications. The starting point in the flyway documentation can be found here
https://flywaydb.org/documentation/api/
flyway works with a standard JDBC DataSource and so you can code the database creation process in Java and then have flyway handle the schema management. In many environment you are likely to require 2 steps anyway as the database/schema creation will need admin rights to the database, while the ongoing schema management will need an account with reduced access rights.
what you need is to implement the interface FlywayCallback
in order to kick start the migration manually from you code you can use the migrate() method on the flyway class
tracking the migration process can be done through the MigrationInfoService() method of the flyway class
Unfortunately if your app has a single datasource that expects the schema to exist, Flyway will not be able to use that datasource to create the scheme. You must create another datasource that is not bound to the schema and use the unbounded datasource by way of a FlywayMigrationStrategy.
In your properties file:
spring:
datasource:
url: jdbc:mysql://localhost:3306/myschema
bootstrapDatasource:
url: jdbc:mysql://localhost:3306
In your config file:
#Bean
#Primary
#ConfigurationProperties("spring.datasource")
public DataSourceProperties primaryDataSourceProperties() {
return new DataSourceProperties();
}
#Bean
#Primary
#ConfigurationProperties("spring.datasource")
public DataSource primaryDataSource() {
return primaryDataSourceProperties().initializeDataSourceBuilder().build();
}
#Bean
#ConfigurationProperties("spring.bootstrapDatasource")
public DataSource bootstrapDataSource() {
return DataSourceBuilder.create().build();
}
And in your FlywayMigrationStrategy file:
#Inject
#Qualifier("bootstrapDataSource")
public void setBootstrapDataSource(DataSource bootstrapDataSource) {
this.bootstrapDataSource = bootstrapDataSource;
}
#Override
public void migrate(Flyway flyway) {
flyway.setDataSource(bootstrapDataSource);
...
flyway.migrate()
}
I followed the tutorial for dropwizard and hibernate without problems. Now I have non trivial annotations in my entities, and I would like hibernate to generate the tables for me, and stuff like that.So, how can I change hibernate's configuration? Can I give it a hibernate.cfg.xml? If I can, do I have to set up the connection again?
I found this PR,
but it doesn't seem to be in the public release yet (no hibernateBundle.configure in my jars)
But maybe I'm looking for the wrong thing. So far, I'm just trying to set hibernate.hbm2dll.auto. After all, there might be an other way to enable hibernate table generation in Dropwizard... So, any help?
Thank you.
Edit: I approached the problem from another angle, to explicitly create the schema instead of using hbm2ddl.auto. See proposed answer.
Edit: Problem solved! Doing this in the YAML config currently works: (Dropwizard 0.7.1)
database:
properties:
hibernate.dialect: org.hibernate.dialect.MySQLDialect
hibernate.hbm2ddl.auto: create
(from this answer)
Old answer:
This is what I am currently using: A class that calls hibernate's SchemaExport to export the schema to a SQL file or to modify the database. I just run it after changing my entities, and before running the application.
public class HibernateSchemaGenerator {
public static void main(String[] args) {
Configuration config = new Configuration();
Properties properties = new Properties();
properties.put("hibernate.dialect", "org.hibernate.dialect.MySQLDialect");
properties.put("hibernate.connection.url", "jdbc:mysql://localhost:3306/db");
properties.put("hibernate.connection.username", "user");
properties.put("hibernate.connection.password", "password");
properties.put("hibernate.connection.driver_class", "com.mysql.jdbc.Driver");
properties.put("hibernate.show_sql", "true");
config.setProperties(properties);
config.addAnnotatedClass(MyClass.class);
SchemaExport schemaExport = new SchemaExport(config);
schemaExport.setOutputFile("schema.sql");
schemaExport.create(true, true);
}
}
I didn't know about hibernate tools before. So this code example can be used in the service initialization to act like hbm2ddl.auto = create.
I'm currently using it just by running the class (from eclipse or maven) to generate and review the output SQL.