247 lines
12 KiB
Markdown
247 lines
12 KiB
Markdown
---
|
||
title: Operations handbook
|
||
---
|
||
|
||
## Understanding app and server configuration
|
||
|
||
Co-op Cloud stores per-app configuration in the `$USER/.abra/servers` directory, on whichever machine you're running `abra` on (by default, your own workstation).
|
||
|
||
The format of these configuration files is the same environment variable syntax used by Docker (with the `env_file:` statement in a `docker-compose.yml` file, or the `--env-file` option to `docker run`) and `direnv`:
|
||
|
||
```
|
||
abra app example_wordpress config
|
||
TYPE=wordpress
|
||
|
||
DOMAIN=wordpress.example.com
|
||
## Domain aliases
|
||
EXTRA_DOMAINS=', `www.wordpress.example.com`'
|
||
LETS_ENCRYPT_ENV=production
|
||
...
|
||
```
|
||
|
||
`abra` doesn't mind if `~/.abra/servers`, or any of its subdirectories, is a [symlink], so you can keep your app definitions wherever you like!
|
||
|
||
```
|
||
mv ~/.abra/servers/ ~/coop-cloud
|
||
ln -s ~/coop-cloud ~/.abra/servers
|
||
```
|
||
|
||
### Backing up your app configuration
|
||
|
||
Just make sure the `~/.abra/servers` is included in the configuration of your favourite backup tool.
|
||
|
||
You can optionally also backup `~/.abra/apps`, if you'd like to keep an exact copy of the application versions you currently have deployed. Otherwise, they'll be automatically downloaded the first time you run an `abra app...` command.
|
||
|
||
You don't need to worry about `~/.abra/vendor` or `~/.abra/src` directories, which will be likewise recreated automatically as and when you need them.
|
||
|
||
<a id="version-control"></a>
|
||
|
||
### Version-control your app configs (using git)
|
||
|
||
Because `~/.abra/servers` is a collection of plain-text files, it's easy to keep your backup configuration in a version control system (we use `git`, others would almost certainly work).
|
||
|
||
This is particularly recommended if you're collaborating with others, so that you can all run `abra app...` commands without having to maintain your own separate, probably-conflicting, configuration files.
|
||
|
||
In the simple case where you only have one server configured with `abra`, or everyone in your team is using the same set of servers, you can version-control the whole `~/.abra/servers` directory:
|
||
|
||
```
|
||
cd ~/.abra/servers
|
||
git init
|
||
git add .
|
||
git commit -m "Initial import"
|
||
```
|
||
|
||
!!! warning "Test your revision-control self-discipline"
|
||
|
||
`abra` does not yet help keep your app definitions are up-to-date.
|
||
|
||
Make sure to run `git add` / `git commit` after making configuration changes, and `cd ~/.abra/servers && git pull` before running `abra app...` commands.
|
||
|
||
Patches to add some safety checks and auto-updates would be very welcome! 🙏
|
||
|
||
### Collaborating with multiple teams
|
||
|
||
In a more complex situation, where you're using Co-op Cloud to manage several servers, and you're collaborating with different people on different servers, you can set up **a separate repository for each subdirectory in `~/.abra/servers`**, or even a mixture of single-server and multi-server repositories:
|
||
|
||
```
|
||
ls -l ~/.abra/servers
|
||
# Example.com's own app configuration:
|
||
lrwxrwxrwx. 1 user user 49 Oct 30 22:42 swarm.example.com -> /home/user/Example/coop-cloud-apps/swarm.example.com
|
||
# Configuration for one of Example.com's clients – part of the same repository:
|
||
lrwxrwxrwx. 1 user user 49 Oct 30 22:42 swarm.client.com -> /home/user/Example/coop-cloud-apps/swarm.client.com
|
||
# A completely separate project, part of a different repository:
|
||
lrwxrwxrwx. 1 user user 49 Oct 30 22:42 swarm.demonstration.com -> /home/user/Demonstration/coop-cloud-apps
|
||
```
|
||
|
||
To make setting up these symlinks easier, you might want to include a simple installer script in your configuration repositories.
|
||
|
||
We don't have a public example of this yet, but something like this should do the trick:
|
||
|
||
1. Save this as `Makefile` in your repository:
|
||
|
||
```
|
||
# -s symlink, -f force creation, -F don't create symlink in the target dir
|
||
link:
|
||
@mkdir -p ~/.abra/servers/
|
||
@for SERVER in $$(find -maxdepth 1 -type d -name "[!.]*"); do \
|
||
echo ln -sfF "$$(pwd)/$${SERVER#./}" ~/.abra/servers/ ; \
|
||
ln -sfF "$$(pwd)/$${SERVER#./}" ~/.abra/servers/ ; \
|
||
done
|
||
```
|
||
|
||
This will set up symlinks from each directory in your repository to a correspondingly-named directory in `~/.abra/servers` – if your repository has a `swarm.example.com` directory, it'll be linked as `~/.abra/servers/swarm.example.com`.
|
||
|
||
2. Tell your collaborators (e.g. in the repository's `README`), to run `make` in their repository check-out.
|
||
|
||
!!! warning "You're on your own!"
|
||
|
||
As with the [simple repository set-up above](#version-control), `abra` doesn't yet help you update your version control system when you make changes, nor check version control to make sure you have the latest configuration.
|
||
|
||
Make sure to `commit` and `push` after you make any configuration changes, and `pull` before running any `abra app...` commands.
|
||
|
||
### Even more granularity?
|
||
|
||
The plain-text, file-based configuration format means that you could even keep the configuration for different apps on the same server in different repositories, e.g. having `git.example.com` configuration in a separate repository to `wordpress.example.com`, using per-file symlinks.
|
||
|
||
We don't currently recommend this, because it might set inaccurate expectations about the security model – remember that, by default, **any user who can deploy apps to a Docker Swarm can manage _any_ app in that swarm**.
|
||
|
||
[symlink]: https://en.wikipedia.org/wiki/Symlink
|
||
|
||
## Running abra server side
|
||
|
||
If you're on an environment where it's hard to run Docker, or command-line programs in general, you might want to install `abra` on a server instead of your local computer.
|
||
|
||
To install `abra` on a different server than you'll be hosting your apps, just follow [getting started guide](/overview/) as normal.
|
||
|
||
If you want to install `abra` on the same server, there's one change.
|
||
|
||
Instead of providing your SSH connection details when you run `abra server add ...`, just use `default`:
|
||
|
||
```
|
||
abra server add default
|
||
```
|
||
|
||
!!! note "Technical details"
|
||
|
||
This will tell `abra` to look at the Docker system running on the server, instead of a remote one.
|
||
|
||
Make sure to back up your `~/abra/` directory on the server, or put it in version control, as well as other files you'd like to.
|
||
|
||
## Managing secret data
|
||
|
||
Co-op Cloud uses [Docker Secrets] to handle sensitive data, like database passwords and API keys, securely:
|
||
|
||
```
|
||
DOCKER_CONTEXT=swarm.example.com docker secret ls
|
||
example_mediawiki_db_password_v1
|
||
example_wordpress_db_password_v1
|
||
```
|
||
|
||
`abra` includes several commands to make it easier to manage secrets:
|
||
|
||
- `abra app <app> secret generate` -- to auto-generate a single secret, or all secrets defined by the app, and store them in the Docker Swarm store,
|
||
- `abra app <app> secret insert` -- to insert a single secret value from the Docker Swarm store,
|
||
- `abra app <app> secret delete` -- to remove a single secret, or all secrets defined in the app, from the Docker Swarm store.
|
||
|
||
<a id="versions"></a>
|
||
|
||
### Secret versions
|
||
|
||
You will notice `v1` in the example secret names above: like Docker Configs, Docker Secrets are [immutable], which means that their values can't be changed after they're set. To accommodate this, Co-op Cloud uses the established convention of "secret versions". Every time you change (rotate) a secret, you will insert it as a new version.
|
||
|
||
Because secret versions are managed per-instance by the people deploying their apps, secret versions are stored in the `.env` file for each app:
|
||
|
||
```
|
||
find -L ~/.abra/servers/ -name '*.env' -print0 | xargs -0 grep -h SECRET
|
||
OIDC_CLIENT_SECRET_VERSION=v1
|
||
RPC_SECRET_VERSION=v1
|
||
CLIENT_SECRET_VERSION=v1
|
||
...
|
||
```
|
||
|
||
If you try and add a secret version which already exists, Docker will helpfully complain:
|
||
|
||
```
|
||
abra app example_wordpress secret insert db_password v1 foobar
|
||
Error response from daemon: rpc error: code = AlreadyExists desc = secret example_wordpress_db_password_v1 already exists
|
||
```
|
||
|
||
By default, new app instances will look for `v1` secrets.
|
||
|
||
### Generating secrets automatically
|
||
|
||
You can generate secrets in one of two ways:
|
||
|
||
1. While running `abra app new <type>`, by passing `--secrets`
|
||
2. At any point once an app instance is defined, by running `abra app <app> secret generate ...` (see `abra help secret generate` for full options)
|
||
|
||
!!! note "How are secrets generated?"
|
||
|
||
Depending on how the app is configured, you will require the `pwqgen` (from `passwdqc`) and `pwgen` binaries by default, although you can specify your own password-generation app when running `abra <app> secret generate` by providing the `<cmd>` argument.
|
||
|
||
### Inserting secrets manually
|
||
|
||
For third-party API tokens, like OAuth client secrets, or keys for services like Mailgun, you will be storing values you already have as the appropriately-named Docker secrets. `abra` provides a convenient interface to the underlying `docker secret create` command:
|
||
|
||
```
|
||
abra app example_wordpress secret insert db_password v2 "your-secret-here"
|
||
```
|
||
|
||
### Rotating a secret
|
||
|
||
So, given how [secret versions](#versions) work, here's how you change a secret:
|
||
|
||
1. Find out the current version number of the secret, e.g. by running `abra app example_wordpress config`, and choose a new one. Let's assume it's currently `v1`, so by convention the new secret will be `v2`.
|
||
2. Generate or insert the new secret:
|
||
```
|
||
abra app example_wordpress secret generate db_password v2
|
||
```
|
||
or
|
||
```
|
||
abra app example_wordpress secret insert db_password v2 "foobar"
|
||
```
|
||
3. Edit the app configuration to change which secret version the app will use:
|
||
```
|
||
abra app example_wordpress config
|
||
```
|
||
4. Re-reploy the app with the new secret version:
|
||
```
|
||
abra app example_wordpress deploy
|
||
```
|
||
|
||
### Storing secrets in `pass`
|
||
|
||
The Co-op Cloud authors use the [UNIX `pass` tool][pass] to share sensitive data, including Co-op Cloud secrets, and `abra <app> secret...` commands include a `--pass` option to automatically manage generated / inserted secrets:
|
||
|
||
```
|
||
# Store generated secrets in `pass`:
|
||
abra app new wordpress --secrets --pass
|
||
abra app example_wordpress secret generate --all --pass
|
||
# Store inserted secret in `pass`:
|
||
abra app example_wordpress secret insert db_password v2 --pass
|
||
# Remove secrets from Docker, and `pass`:
|
||
abra app example_wordpress secret rm --all --pass
|
||
```
|
||
|
||
This functionality currently relies on our specific `pass` structure; patches to make that configurable are very welcome!
|
||
|
||
## Networking
|
||
|
||
!!! note "So dark the con of Docker Networking"
|
||
|
||
Our understanding of Docker networking is probably wrong. We're working on it. Plz send halp :pray:
|
||
|
||
### Traefik networking
|
||
|
||
[Traefik](https://doc.traefik.io/traefik/) is our core web proxy, all traffic on a Co-op Cloud deployment goes through a running Traefik container. When setting up a new Co-op Cloud delpyment, `abra` creates a "global" [overlay network](https://docs.docker.com/network/overlay/) which traefik is hooked up to. This is the network that other apps use to speak to traefik and get traffic routed to them. Not every service in every app is also included in this network and hence not internet-facing (by convention, we name this network `internal`, see more below).
|
||
|
||
### App networking
|
||
|
||
By convention, the main `app` service is wired up to the "global" traefik overlay network. This container is the one that should be publicy reachable on the internet. The other services in the app such as the database and caches should be not be publicly reachable or visible to other apps on the same instance.
|
||
|
||
To deal with this, we make an additional "internal" network for each app which is namespaced to that app. So, if you deploy a Wordpress instance called `my_wordpress_blog` then there will be a network called `my_wordpress_blog_internal` created. This allows all the services in an app to speak to each other but not be reachable on the public internet.
|
||
|
||
### Avoiding service namespace conflicts
|
||
|
||
When referencing an `app` service in a config file, you should prefix with the `STACK_NAME` to avoid namespace conflicts (because all these containers sit on the traefik overlay network). You might want to do something like this `{{ env "STACK_NAME" }}_app` (using the often obscure dark magic of the Golang templating language). You can find examples of this approach used in the [Peertube recipe](https://git.coopcloud.tech/coop-cloud/peertube/src/commit/d1b297c5a6a23a06bf97bb954104ddfd7f736568/nginx.conf.tmpl#L9).
|