Don't duplicate Postgres databases

PgVector is an extension for Postgres. Before this commit, we would add
a pgvector and a postgres Docker Compose service. The resulting app
doesn't start up, as there are now two JdbcConnectionDetails in the
context.

After that commit, we only add the pgvector Docker Compose service if
both Postgres and PgVector is selected.

Closes spring-iogh-1458

start-site/src/main/java/io/spring/start/site/extension/dependency/postgresql/PgVectorProjectGenerationConfiguration.java

@@ -36,6 +36,7 @@
  * Configuration for generation of projects that depend on PgVector.
  *
  * @author Eddú Meléndez
+ * @author Moritz Halbritter
  */
 @Configuration(proxyBeanMethods = false)
 @ConditionalOnRequestedDependency("spring-ai-vectordb-pgvector")
@@ -71,13 +72,15 @@ ServiceConnectionsCustomizer pgvectorServiceConnectionsCustomizer(DockerServiceR
 	@Bean
 	@ConditionalOnRequestedDependency("docker-compose")
 	ComposeFileCustomizer pgvectorComposeFileCustomizer(DockerServiceResolver serviceResolver) {
-		return (composeFile) -> serviceResolver.doWith("pgvector",
-				(service) -> composeFile.services()
-					.add("pgvector",
-							service.andThen((builder) -> builder.environment("POSTGRES_USER", "myuser")
-								.environment("POSTGRES_DB", "mydatabase")
-								.environment("POSTGRES_PASSWORD", "secret")
-								.label("org.springframework.boot.service-connection", "postgres"))));
+		return (composeFile) -> serviceResolver.doWith("pgvector", (service) -> {
+			composeFile.services().remove("postgres");
+			composeFile.services()
+				.add("pgvector",
+						service.andThen((builder) -> builder.environment("POSTGRES_USER", "myuser")
+							.environment("POSTGRES_DB", "mydatabase")
+							.environment("POSTGRES_PASSWORD", "secret")
+							.label("org.springframework.boot.service-connection", "postgres")));
+		});
 	}
 
 }

start-site/src/main/java/io/spring/start/site/extension/dependency/postgresql/PostgresqlProjectGenerationConfiguration.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -47,12 +47,16 @@ ServiceConnectionsCustomizer postgresqlServiceConnectionsCustomizer(DockerServic
 	@Bean
 	@ConditionalOnRequestedDependency("docker-compose")
 	ComposeFileCustomizer postgresqlComposeFileCustomizer(DockerServiceResolver serviceResolver) {
-		return (composeFile) -> serviceResolver.doWith("postgres",
-				(service) -> composeFile.services()
-					.add("postgres",
-							service.andThen((builder) -> builder.environment("POSTGRES_USER", "myuser")
-								.environment("POSTGRES_DB", "mydatabase")
-								.environment("POSTGRES_PASSWORD", "secret"))));
+		return (composeFile) -> serviceResolver.doWith("postgres", (service) -> {
+			if (composeFile.services().has("pgvector")) {
+				return;
+			}
+			composeFile.services()
+				.add("postgres",
+						service.andThen((builder) -> builder.environment("POSTGRES_USER", "myuser")
+							.environment("POSTGRES_DB", "mydatabase")
+							.environment("POSTGRES_PASSWORD", "secret")));
+		});
 	}
 
 }

start-site/src/test/java/io/spring/start/site/extension/dependency/postgresql/PgVectorProjectGenerationConfigurationTests.java

@@ -29,6 +29,7 @@
  * Tests for {@link PgVectorProjectGenerationConfiguration}.
  *
  * @author Eddú Meléndez
+ * @author Moritz Halbritter
  */
 class PgVectorProjectGenerationConfigurationTests extends AbstractExtensionTests {
 
@@ -45,4 +46,10 @@ void createsPostgresService() {
 		assertThat(composeFile(request)).hasSameContentAs(new ClassPathResource("compose/pgvector.yaml"));
 	}
 
+	@Test
+	void shouldOnlyHavePgVectorIfPostgresAndPgVectorIsSelected() {
+		ProjectRequest request = createProjectRequest("docker-compose", "postgresql", "spring-ai-vectordb-pgvector");
+		assertThat(composeFile(request)).hasSameContentAs(new ClassPathResource("compose/pgvector.yaml"));
+	}
+
 }