polish

content/posts/deploying-applications-to-flyio-without-docker/index.md

@@ -2,7 +2,7 @@
 categories = ["devops"]
 date = 2024-10-05
 summary = "A quick guide to deploying apps to Fly.io without a local Docker installation"
-draft = true
+draft = false
 slug = "deploying-applications-to-flyio-without-docker"
 tags = ["fly.io", "docker", "nix"]
 title = "Deploying applications to Fly.io without Docker"
@@ -14,30 +14,35 @@ title = "Deploying applications to Fly.io without Docker"
 
 [Fly.io](https://fly.io) is one of the many players in the "We run your app close to your users" space. I've used their services for just over a couple years to run my personal instance of [linkleaner](https://github.com/msfjarvis/linkleaner). Recently I ran into a combination of a platform outage and localized issue that necessitated recreating the app from scratch, and I decided to try doing so locally rather than my usual CI-based deployment system.
 
-Deployments with Fly.io usually start with a Docker/OCI image. Fly.io requires this image to either exist in their own OCI registry at `registry.fly.io` or any other **publicly** accessible registry. The common way to do this is to use a Dockerfile and build the image locally, then use their [flyctl](https://github.com/superfly/flyctl) CLI to upload that image from your local Docker registry to `registry.fly.io` and then deploy the app.
+Deployments with Fly.io usually start with a Docker/OCI image. Fly.io requires this image to either exist in their own OCI registry at registry.fly.io, or any other publicly accessible registry. The common way to do this is to use a Dockerfile and build the image locally, then use their [flyctl](https://github.com/superfly/flyctl) CLI to upload that image from your local Docker registry to registry.fly.io and then deploy the app.
 
-Since I use [Nix](https://nixos.org) as my Docker image builder (check out [this talk](https://xeiaso.net/talks/2024/nix-docker-build/) that explains why it might be preferable over Docker itself), I do not run Docker locally and had no plans to start now. This guide is mostly the result of that stubbornness so I intend to keep it short.
+Since I use [Nix](https://nixos.org) as my Docker image builder (check out [this talk](https://xeiaso.net/talks/2024/nix-docker-build/) that explains why one would prefer it over Docker itself), I do not run Docker locally and had no plans to start now. This guide is mostly the result of that stubbornness so I intend to keep it short.
 
 ## Setting up
 
-The main ingredient of this is the [skopeo](https://github.com/containers/skopeo) CLI that allows one to interact with remote OCI registries. We'll replace the Fly.io Docker integration steps with [`skopeo copy`](https://github.com/containers/skopeo/blob/03ca12ed56db3e5e46805b0d8a95a1207a0921ea/docs/skopeo-copy.1.md) that allows copying Docker archives directly to a registry.
+The main ingredient of this is the [skopeo](https://github.com/containers/skopeo) CLI that allows one to interact with remote OCI registries. We'll replace the Fly.io Docker integration steps with [skopeo copy](https://github.com/containers/skopeo/blob/03ca12ed56db3e5e46805b0d8a95a1207a0921ea/docs/skopeo-copy.1.md) that allows copying Docker archives directly to a registry.
 
-You're also going to need a Fly.io token to authenticate with `registry.fly.io`. With `flyctl` installed you can run `fly tokens create deploy` to get an auth token usable for the purpose. I stored mine in a `FLY_AUTH_TOKEN` environment variable that will be referenced later.
+You're also going to need a Fly.io token to authenticate with registry.fly.io. With `flyctl` installed you can run `fly tokens create deploy` to get an auth token usable for the purpose. I stored mine in a `FLY_AUTH_TOKEN` environment variable that will be referenced later.
 
 ## Building and deploying
 
 First we need to build the image. With Nix it is as easy as running `nix build .#container` (since I declare the OCI image as a [package](https://github.com/msfjarvis/linkleaner/blob/69564ab458abe77e55d090d29ff970a68c1a985c/flake.nix#L83-L93) in my Nix configuration) which will generate a symlink at `./result` pointing to a Docker image tarball.
 
-Now to the actual deployment: assuming your app is already up and running on the Fly.io platform, you just need to copy this image over to their registry and trigger a new deployment. `skopeo` makes this rather easy.
+```
+➜ ls -l result
+lrwxrwxrwx msfjarvis users 74 B Sat Oct  5 19:31:52 2024  result ⇒ /nix/store/h0jgv00fg68d7gsaadd11ydpk6wxxn8w-docker-image-linkleaner.tar.gz
+```
+
+Now to the actual deployment: assuming your app is already set up (`fly apps create`), you just need to copy this image over to their registry and trigger a new deployment. `skopeo` makes this rather easy.
 
 ```
 skopeo \
   # Remove the need for a policy file since we only need this for a one off thing
   --insecure-policy \
   copy \
-  # The source argument, which is a docker image archive available as the `./result` file
+  # The source argument, which is a docker image archive at `./result`
   docker-archive:./result \
-  # The destination argument, the `build.image` value from your fly.toml file
+  # The destination argument, the `build.image` value from your fly.toml
   docker://registry.fly.io/linkleaner:latest \
   # Injecting the previously generated credentials
   --dest-creds x:"$FLY_AUTH_TOKEN" \