Using Dagger to run containers that don't exit

[obtuse marlin]

Is there a way to use dagger to effectively do a "docker run" command on a dagger.Container object? I've tried just using container.Stdout(ctx) but I can not find the mongo container with docker ps -a. I'm probably missing something obvious, or trying to mis-use CI/CD to run app code

In my use-case I do not need to push the images to a remote registry, I want to just build the mongo container and start running it

func BuildMongo(ctx context.Context, client *dagger.Client) *dagger.Container {
  err := godotenv.Load()
  if err != nil {
      panic(err)
  }

  username := os.Getenv("MONGO_INITDB_ROOT_USERNAME")
  password := os.Getenv("MONGO_INITDB_ROOT_PASSWORD")

    mongoContainer := client.Container().From("docker.io/mongo:latest").WithEnvVariable("MONGO_INITDB_ROOT_USERNAME", username).WithEnvVariable("MONGO_INITDB_ROOT_PASSWORD", password)

    mongoContainer.WithEntrypoint([]string{"-d", "hak247", "--port", "27017"})
    return mongoContainer
}

func StartMongo(ctx context.Context, mongoContainer *dagger.Container) {
    mongoContainer.Stdout(ctx)
}

[low skiff]

Sounds like you're looking to run Mongo as a service @obtuse marlin? You'll want the with_exposed_port method on your container using the 27017 port you've got in your entrypoint: https://dagger-io.readthedocs.io/en/sdk-python-v0.5.3/api.html#dagger.api.gen.Container.with_exposed_port

I'd also suggest you use client.set_secret for the Mongo password, and container.with_secret_variable to add it to your container. These are demonstrated here: https://dagger.io/blog/dagger-engine-0-4-0,

[obtuse marlin]

Thanks @low skiff I'll try it out as a service

[low skiff]

Once you add the with_exposed_port method to the Mongo container you'll need with_service_binding on whatever container calls the Mongo service

[obtuse marlin]

nice, I'll paste my updated code if I get it working

[coarse axle]

Here's more info about this: https://docs.dagger.io/757394/use-service-containers

[obtuse marlin]

Updated the mongo code with @low skiff's suggestions. Ended up just publishing the mongo image and running it with bash docker run instead of services as I needed the mongo container to run standalone. Thanks for help guys, can close this.

func BuildMongo(ctx context.Context, client *dagger.Client, portNo int) (*dagger.Container, error) {
    err := godotenv.Load()
    if err != nil {
        return nil, err
    }

    username, err := client.Host().EnvVariable("MONGO_INITDB_ROOT_USERNAME").Value(ctx)
    if err != nil {
        return nil, err
    }
    password, err := client.Host().EnvVariable("MONGO_INITDB_ROOT_PASSWORD").Value(ctx)
    if err != nil {
        return nil, err
    }
    passwordSecret := client.SetSecret("MONGO_INITDB_ROOT_PASSWORD", password)

    mongoContainer := client.Container().From("docker.io/mongo:latest").WithEnvVariable("MONGO_INITDB_ROOT_USERNAME", username).WithSecretVariable("MONGO_INITDB_ROOT_PASSWORD", passwordSecret).WithExposedPort(portNo)

    mongoContainer.WithEntrypoint([]string{"-d", "hak247", "--port", strconv.Itoa(portNo)})
    return mongoContainer, nil
}

[coarse axle]

@sacred rose @pliant quarry as we move services to standard Gateway API, how about adding a feature were users keep them running even after the pipeline finishes? It's not the first time I recall seeing this kind of request

[sacred rose]

worth considering, but it would have huge API implications. mainly concerning how to find and stop the service again, potentially in a later session. for example, Buildkit doesn't support querying for containers, and doesn't support setting a deterministic container ID/name, etc.

much more complex vs. just running it like a regular container

[coarse axle]

agree.. In that case maybe have a way to keep them alive until the session is closed at least? That way adding a Thread.Sleep in the code could help with troubleshooting. The fact that service containers are killed 10s after they're used leaves little room for poking with them.. Just throwing ideas... maybe it's worth starting a discussion if there's none

[sacred rose]

you can already run them like svc.ExitCode(ctx) since they're regular containers, but i'm not sure if our docs cover that already