containerd-shim-spin shoud support outbound capabilities (eg redis)

[ThorstenHans]

containerd-shim-spin currently supports simple workloads only. It should support all outbound capabilities provided by Spin like Redis and PostgreSQL.

When deploying a Spin application that uses outbound-redis::publish currently results in the "pod" failing with:

Normal   Created  1s (x3 over 18s)  kubelet   Created container main
Warning  Failed   1s (x3 over 18s)  kubelet   Error: failed to start containerd task "main": unknown import: `outbound-redis::publish` has not been defined: unknown

[Mossaka]

Yes, as of today, the spin trigger only support the HTTP capability.

Let me try to describe the work needed to support other capabilities:

update build_spin_trigger function to include other triggers based on spin application struct https://github.com/deislabs/containerd-wasm-shims/blob/main/containerd-shim-spin-v1/src/main.rs#L83-L98.

The trigger type can be found in https://github.dev/fermyon/spin/blob/8dfc4d6fbb31d624eb034f78640cb207bec1f682/src/commands/up.rs#L146-L149.

[ThorstenHans]

Hey @Mossaka thanks for the details, however I was referring to outbound redis in this particular issue, not about the redis trigger

[Mossaka]

Ah okay. The outbound redis should be avialable in spin v0.6.0, which I added in this PR #55 . I will try to create an example that uses the outbound redis capability.

[ThorstenHans]

Yes spin isn't the problem here. The shim has to load the output capabilities from spin explicitly, which is not done at the moment.

[ChristianWeyer]

Do you have any idea what to do here @Mossaka ?

[Mossaka]

Yes, sorry for getting back to you late. I am looking into in this week.

[Mossaka]

I just tried creating a Spin application with using the outbound redis capability. The spin application is written in rust:

use anyhow::{anyhow, Result};
use spin_sdk::{
    http::{internal_server_error, Request, Response},
    http_component, redis,
};

const REDIS_ADDRESS_ENV: &str = "REDIS_ADDRESS";
const REDIS_CHANNEL_ENV: &str = "REDIS_CHANNEL";

#[http_component]
fn hello_world(_req: Request) -> Result<Response> {
    let address = std::env::var(REDIS_ADDRESS_ENV)?;
    let channel = std::env::var(REDIS_CHANNEL_ENV)?;

    // Get the message to publish from the Redis key "mykey"
    let payload = redis::get(&address, "mykey").map_err(|_| anyhow!("Error querying Redis"))?;

    // Set the Redis key "spin-example" to value "Eureka!"
    redis::set(&address, "spin-example", &b"Eureka!"[..])
        .map_err(|_| anyhow!("Error executing Redis set command"))?;

    // Set the Redis key "int-key" to value 0
    redis::set(&address, "int-key", format!("{:x}", 0).as_bytes())
        .map_err(|_| anyhow!("Error executing Redis set command"))?;
    let int_value = redis::incr(&address, "int-key")
        .map_err(|_| anyhow!("Error executing Redis incr command",))?;
    assert_eq!(int_value, 1);

    // Publish to Redis
    match redis::publish(&address, &channel, &payload) {
        Ok(()) => Ok(http::Response::builder().status(200).body(None)?),
        Err(_e) => internal_server_error(),
    }
    Ok(http::Response::builder().status(200).body(None)?)
}

Then I deployed this spin service and a redis service in kubernetes using the spin shim.

Everything works fine for me.

One thing I found interesting is that for some reason, spin redis cannot find the redis-server using kubernetes DNS service's A/AAAA records like redis://redis-service.default.svc.cluster.local:6379. I had to find the redis service IP address by running k exec -it redis -- env and set the value of REDIS_SERVICE_SERVICE_HOST to REDIS_ADDRESS environment in spin.toml.

I am not sure if this is a shim's bug or spin's bug.

Hope this helps!

[squillace]

hey @ThorstenHans it appears that the version of spin in the shim does do outbound redis work successfully (with some oddities, as @Mossaka mentions). Can you confirm this? If you're using AKS to test, Microsoft needs to rebuild the shim and update the service, which it hopes to do this month.

[Mossaka]

Closing this one out as we can't reproduce ths issue.

[ThorstenHans]

I'll spin up a new AKS cluster these days and give it a try again. I'll keep you posted @Mossaka

[squillace]

wait wait... new one flying in very shortly!!!