From Spring Boot

Migrating from Spring Boot

This guide helps you migrate existing Spring Boot applications to qqq.

Why Migrate?

Compatibility

qqq runs on the JVM and can coexist with Spring components during migration.

Migration Steps

1. Add qqq Dependencies

<dependency>
    <groupId>io.qrun</groupId>
    <artifactId>qqq-backend-core</artifactId>
    <version>${qqq.version}</version>
</dependency>

2. Convert Entities

Spring Entity:

@Entity
@Table(name = "orders")
public class Order {
    @Id @GeneratedValue
    private Long id;
    private String status;
    // getters/setters
}

qqq Table:

@QTableMetaData(name = "order")
public class OrderTable implements TableMetaDataProducer {
    @Override
    public QTableMetaData produce(QInstance qInstance) {
        return new QTableMetaData()
            .withName("order")
            .withField(new QFieldMetaData("id", QFieldType.LONG))
            .withField(new QFieldMetaData("status", QFieldType.STRING));
    }
}

3. Convert Services to Processes

Spring services with business logic become qqq processes.

4. Migrate Controllers

qqq auto-generates REST APIs. Custom endpoints become process APIs.

Incremental Migration

Migrate table by table:

1. Start with simple tables

2. Add relationships gradually

3. Convert services to processes

4. Remove Spring controllers as qqq APIs replace them

Keeping Spring Components

Some Spring components can remain: