java 36 lines · 6 steps

Customizing Flyway migrations in Spring

A Spring config class builds a fully customized Flyway instance and controls exactly how migrations run at startup.

Explained by highlit

Spring Intermediate database-migrations flyway dependency-injection configuration startup

1package com.acme.billing.config;
2 
3import org.flywaydb.core.Flyway;
4import org.flywaydb.core.api.MigrationVersion;
5import org.flywaydb.core.api.configuration.FluentConfiguration;
6import org.springframework.boot.autoconfigure.flyway.FlywayMigrationStrategy;
7import org.springframework.context.annotation.Bean;
8import org.springframework.context.annotation.Configuration;
9 
10import javax.sql.DataSource;
11 
12@Configuration
13public class FlywayConfig {
14 
15    @Bean
16    public Flyway flyway(DataSource dataSource) {
17        FluentConfiguration configuration = Flyway.configure()
18                .dataSource(dataSource)
19                .locations("classpath:db/migration")
20                .baselineOnMigrate(true)
21                .baselineVersion(MigrationVersion.fromVersion("0"))
22                .table("schema_history")
23                .validateOnMigrate(true)
24                .cleanDisabled(true);
25 
26        return configuration.load();
27    }
28 
29    @Bean
30    public FlywayMigrationStrategy migrationStrategy() {
31        return flyway -> {
32            flyway.repair();
33            flyway.migrate();
34        };
35    }
36}

01 / 01

STEP 01

Walkthrough

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Three takeaways

1Defining your own Flyway bean overrides Spring Boot's auto-configured defaults so you control every migration setting.
2baselineOnMigrate lets Flyway adopt an existing non-empty database instead of failing on first run.
3A FlywayMigrationStrategy replaces the default migrate-on-startup behavior with your own sequence of steps.

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