richardstephens/rules_jooq_flyway_codegen

Bazel rule for generating jOOQ classes from a set of Flyway migrations as part of a Bazel build

Bazel rules for jOOQ codegen from Flyway migrations

This Bazel rule will apply Flyway migrations to a database launched in a Testcontainer, use those to run jOOQ's code generator, and produce a source JAR containing your generated classes.

Please note that this rule is still in an alpha-quality state, and the steps taken to import it may change in the future.

To import the rules:

load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
http_archive(
    name = "rules_jooq_flyway_codegen",
    urls = ["https://github.com/richardstephens/rules_jooq_flyway_codegen/releases/download/v0.7/rules_jooq_flyway_codegen-v0.7.tgz"],
    sha256 = "e19bff61d736e727a54e31d843b5d87511974ea41b1cac580d0caa36f3d59f34",
)

You must also define a maven install for the codegen's dependencies: (Note that these dependencies are only for the code generator, they are not propagated to anything that imports the generated classes)

load("@rules_jvm_external//:defs.bzl", rules_jooq_flyway_codegen_maven_install = "maven_install")
rules_jooq_flyway_codegen_maven_install(
    name = "rules_jooq_flyway_codegen_maven",
    artifacts = [
        "org.flywaydb:flyway-core:6.4.4",
        "org.jooq:jooq:3.13.2",
        "org.jooq:jooq-meta:3.13.2",
        "org.jooq:jooq-codegen:3.13.2",
        "org.testcontainers:testcontainers:1.15.1",
        "org.testcontainers:postgresql:1.15.1",
        "org.testcontainers:mariadb:1.15.1",
        "org.testcontainers:mysql:1.15.1",
        "org.postgresql:postgresql:42.2.14",
        "org.mariadb.jdbc:mariadb-java-client:2.6.2",
        "mysql:mysql-connector-java:8.0.21",
        "org.xerial:sqlite-jdbc:3.32.3.2",
    ],
    fetch_sources = True,
    repositories = [
        "https://repo1.maven.org/maven2",
    ],
)

The codegen rule takes as a parameter a resource jar containing your application's flyway migrations. Your directory structure should look something like this:

src/
  myservice/
    db/
      db/
        migration/
          V01_00_00__first_migration.sql
      codegen.xml
      BUILD

Note the double-nested db folders. This is needed because Flyway expects to find its migrations at a path in the form of db/migration by default. We might try to change how this works or make it customisable in the future.

In the BUILD file, you can build a resource jar with your migrations as follows:

java_library(
    name = "migration-jar",
    resource_strip_prefix = "src/myservice/db",
    resources = glob(["db/migration/*.sql"]),
    visibility = ["//src/myservice:__subpackages__"],
)

Note the resource_strip_prefix. That should be the path to this BUILD file

Now you need to set up your codegen.xml file. This will be passed to jOOQ's code generator as is, with the exception of overriding the output directory you specify to a temporary directory for the generated classes. An example codgen.xml file is here, and the jOOQ documentation for the codegen.xml file is here.

Now that you have a resource jar containing your migrations, you can call the code generator like so:

load("@rules_jooq_flyway_codegen//rules_jooq_flyway_codegen:jooqflyway.bzl", "jooqflyway")
jooqflyway(
    name = "myservice-db-classes",
    codegen_xml = "codegen.xml",
    db_type = "mysql",
    jooq_dep = "@maven//:org_jooq_jooq",
    jooq_meta_dep = "@maven//:org_jooq_jooq_meta",
    migration_jar = ":migration-jar",
    visibility = ["//src/myservice:__subpackages__"],
)

Valid options for db type are postgres, mariadb, or mysql at present, but more will be supported in the future.

And that's it! You can now depend on //src/myservice/db:myservice-db-classes