index.ts

import { dag, Container, Directory, object, argument, func } from "@dagger.io/dagger"

@object()
export class Book {
  source: Directory

  // Automatically uses "." as the default source directory
  constructor(
    @argument({ defaultPath: "." }) source: Directory,
  ) {
    this.source = source
  }

  @func()
  env(): Container {
    return dag
      .container()
      .from("python:3.11")
      .withDirectory("/app", this.source)
      .withWorkdir("/app")
      .withMountedCache("/root/.cache/pip", dag.cacheVolume("python-pip"))
      .withExec(["pip", "install", "-r", "requirements.txt"]);
  }

  @func()
  async test(): Promise<string> {
    const postgres = dag
      .container()
      .from("postgres:alpine")
      .withEnvVariable("POSTGRES_DB", "app_test")
      .withEnvVariable("POSTGRES_PASSWORD", "secret")
      .withExposedPort(5432)
      .asService();

    const output = await this.env()
      .withServiceBinding("db", postgres)
      .withEnvVariable("DATABASE_URL", "postgresql://postgres:secret@db/app_test")
      .withExec(["pytest"])
      .stdout();

    return output;
  }

  @func()
  async publish(): Promise<string> {
    await this.test();

    const tag = `ttl.sh/my-fastapi-app-${Math.floor(Math.random() * 10000000)}`;

    const imageRef = await this.env()
      .withExposedPort(8000)
      .withEntrypoint(["fastapi", "run", "main.py"])
      .publish(tag);

    return imageRef;
  }
}