Spring and Flyway - migrate before application context starts up - spring

Question

As the title suggests, I am looking for any means that could help me run Flyway migrations before Springs application context (persistence context to be precise) is loaded. The reason for that is I have few queries that run at the startup of the application. This leads to my tests failing as queries are being executed on database tables that do not yet exist. I am using H2 as my test database. Right now I am using only flyway core dependency:
<dependency>
<groupId>org.flywaydb</groupId>
<artifactId>flyway-core</artifactId>
<version>6.5.0</version>
<scope>test</scope>
</dependency>
and I have a single Flyway configuration class as follows:
#Configuration
class FlywayConfig {
private static final String resourcePath = "classpath:flyway/migrations";
private static final String sampleDataPath = "classpath:flyway/sample_data";
#Bean
Flyway flyway(#Value("${spring.datasource.url}") String dataSource,
#Value("${spring.datasource.username}") String username,
#Value("${spring.datasource.password}") String password) {
FluentConfiguration fluentConfiguration = Flyway.configure().dataSource(dataSource, username, password);
fluentConfiguration.locations(resourcePath, sampleDataPath);
Flyway flyway = fluentConfiguration.load();
return flyway;
}
}
and the properties are defined in application.yml
spring:
datasource:
username: sa
password: sa
url: 'jdbc:h2:mem:testdb;Mode=Oracle;IGNORE_CATALOGS=TRUE;DB_CLOSE_DELAY=-1;'
platform: h2
h2:
console:
enabled: true
jpa:
show-sql: true
What I would like to achieve is that: 1. flyway does migration 2. Spring context loads up (in that particular order)

Answer 1

I managed to be able to acomplish what I wanted by creating DataSource object manually in configuration file (not by Spring automatically from application.yml) and using #DependsOn on the DataSource object. This way I made sure that any possible database connection from the application context would be established once I do the migration in the Flyway bean (which btw I also tweaked). I was cleaning and migrating Flyway right before tests and now I have to do this while initalizing application context beans. Here is the code which worked for me:
#Configuration
class DatabaseConfig {
private static final String resourcePath = "classpath:flyway/migrations";
private static final String sampleDataPath = "classpath:flyway/sample_data";
private static final String dataSourceUrl = "jdbc:h2:mem:testdb;Mode=Oracle;IGNORE_CATALOGS=TRUE;DB_CLOSE_DELAY=-1;";
private static final String username = "sa";
private static final String password = "sa";
#Bean("flyway")
public Flyway flyway() {
FluentConfiguration fluentConfiguration = Flyway.configure().dataSource(dataSourceUrl, username, password);
fluentConfiguration.locations(resourcePath, sampleDataPath);
Flyway flyway = fluentConfiguration.load();
flyway.clean();
flyway.migrate();
return flyway;
}
#DependsOn("flyway")
#Bean
public DataSource dataSource() {
DataSourceBuilder dataSourceBuilder = DataSourceBuilder.create();
dataSourceBuilder.driverClassName("org.h2.Driver");
dataSourceBuilder.url(dataSourceUrl);
dataSourceBuilder.username(username);
dataSourceBuilder.password(password);
return dataSourceBuilder.build();
}
}
and here is the application.yml file (I got rid of datasource related records):
spring:
h2:
console:
enabled: true
jpa:
show-sql: true
flyway:
enabled: false