Rocket 0.5.0-dev unresponsive when containerized

[adamfriedland]

rustc --version

rustc 1.48.0

Rocket version from Cargo lock

name = "rocket"
version = "0.5.0-dev"
source = "git+https://github.com/SergioBenitez/Rocket?branch=master#bcb8b3334b2f4e4f1a213937bcfcbd8599229f63"

Example

Cargo.toml

[package]
authors = ["Adam Friedland"]
edition = "2018"
name = "docker-test"
version = "0.1.0"

[dependencies]
rocket = {git = "https://github.com/SergioBenitez/Rocket", branch = "master"}

Main.rs

#![feature(proc_macro_hygiene, decl_macro)]

#[rocket::get("/")]
fn index() -> &'static str {
    "Hello, world!"
}

#[rocket::launch]
fn rocket() -> rocket::Rocket {
    rocket::ignite().mount("/", rocket::routes![index])
}

Rocket.toml

[debug]
address = "127.0.0.1"
log_level = "debug"
port = 8000

[release]
address = "0.0.0.0"
log_level = "debug"
port = 8000

Dockerfile

# select bin image builder
FROM rustlang/rust:nightly as builder

# create a new empty project for cache persistence
WORKDIR /app/src

# copy source tree
COPY ./ ./

# build for release
RUN cargo build --release

# pipeline to final image
FROM debian:jessie-slim

COPY --from=builder /app/src/target/release/docker-test ./
CMD ["./docker-test"]

Expected in container

Configured for release.
    => address: 0.0.0.0
    => port: 8000
    => workers: 48
    => log level: debug
    => secret key: [zero]
    => limits: forms = 32KiB
    => cli colors: true
    => keep-alive: 5s
    => tls: disabled
Mounting /:
    => GET / (index)
registering with poller
register Token(0) Readable | Writable
set readiness to (empty)
scheduling an accept
Rocket has launched from http://0.0.0.0:8000

What actually outputs to container

docker logs --tail 1000 -f #####

I can cargo build --release locally which produces a binary that I can run without a hitch. It's only when I try to run the compiled image within Docker that it produces no output. I've also just tried to hit the endpoint just in case I somehow messed up my Rocket.toml config but still didn't have any luck. I'm currently using Docker for Windows with the WSL 2 engine enabled.

[SergioBenitez]

There are no known issues of this sort. Are you sure it's actually stalled? As of a recent commit, we switched off logging the launch information by default in release; you'll need to set ROCKET_LOG_LEVEL=debug to see it. We'll be reverting this change in #1410 which has clearly caused much confusion. See #1469 and #1468.

Try setting ROCKET_LOG_LEVEL=debug. Also, try running a shell in the docker container and sending a request.

Also, as a side note, you don't need #![feature(proc_macro_hygiene, decl_macro)] in main.rs.

[cbzehner]

I think I ran into this last night as well. I was able to log into my Docker container with docker exec -it <container-id> /bin/bash and run curl

> curl 0.0.0.0:8000
Hello, world! 

It's odd because Rocket.toml in both @adamfriedland case and my own has log_level = "debug" set for [release]

[adamfriedland]

Well that certainly is strange. If I directly set the environment variables - those being ROCKET_LOG_LEVEL and ROCKET_ADDRESS - within the compose file itself then then it overrides correctly. Is there a possible reason that it ignored my Rocket.toml file in the first place @SergioBenitez ? From the documentation I've read it doesn't require any explicit reference to the file.

I hope that helps with your issue though @cbzehner .

[jebrosen]

FROM debian:jessie-slim
COPY --from=builder /app/src/target/release/docker-test ./
CMD ["./docker-test"]

@adamfriedland I think you left out Rocket.toml from the container, which might explain both problems. Rocket.toml is read from the current working directory at runtime, so if you're using that for configuration it needs to be included in the container or mounted somewhere the container can access it.

[adamfriedland]

Ah that makes perfect sense then. I was unaware that it was read at runtime as opposed to only at compilation. Many thanks to @SergioBenitez and @jebrosen. That solved the issues I was having. Hopefully this helps anyone else experiencing similar issues.