coli-conc Server

Home folder, setup, and configuration.

Work in progress.

To-Dos

• SETUP.md: Clarify that two terminals, one with sudo user and one with cocoda, are necessary
• Add services
• Consider extending data script to support MongoDB as well (instead of having to run docker compose commands manually)
• Have webhook-handler restart certain services when their configurations are updated
  • Currently works by assuming base name (name before first .) as service name for config files
  • We could run srv init ... when a service file is added/updated
  • Ideally this would be more fine-grained so that only running services are restarted
• Test Git cloning instructions
  • Can we configure our server - safely - so that we can also commit changes right from the server?

Dependencies

• Deno
• Docker (rootless)

Setup

See SETUP.md.

Service Management

Services can be managed through the srv script. Run srv --help for instructions.

Define a Docker Compose Service

Create a subdirectory in the services/ folder with a docker-compose.yml file. The folder name defines the service name.

Set up the Compose file as usual, but add the additional environment variables VIRTUAL_HOST, VIRTUAL_PORT (optional, default: 80), VIRTUAL_PATH (optional), and VIRTUAL_DEST (optional). The exposed container also needs to be part of the "nginx" Docker network.

Basic example for Cocoda:

services:
  cocoda:
    image: ghcr.io/gbv/cocoda
    environment:
      - VIRTUAL_HOST=coli-conc.gbv.de
      - VIRTUAL_PATH=/cocoda/app/
      - VIRTUAL_DEST=/
    restart: unless-stopped

networks:
  default:
    external: true
    name: nginx

Explanation of additional environment variables for proxy configuration:

• VIRTUAL_HOST: The hostname (without protocol or path) under which the service should be accessible. Usually that's coli-conc.gbv.de.
• VIRTUAL_PORT: The port under which the service is run (this can be found in the service's Docker documentation). Default: 80.
• VIRTUAL_PATH: The sub-path under which the service should be accessible. Note that some services, mostly front-end applications, might require a trailing slash to work correctly.
• VIRTUAL_DEST: "This environment variable can be used to rewrite the VIRTUAL_PATH part of the requested URL to proxied application." (Please refer to this section of the nginx-proxy documentation.)
  • In most cases, this needs to be set to /.¹

As for environment variables, you can either set them directly in the compose file as in the example above, or you can put them into separate files by specifying env_file:

...
    env_file:
      - $HOME/configs/public.env
      - $HOME/secrets/private.env
...

Later entries override earlier entries. You can check the resulting compose file by running srv configtest my-service.

Initialize, Start, Stop, Restart, or Update a Service

The first time a service is run, it usually needs to be initialize to pull all dependencies:

srv init name-of-service

This will also start the service.

Starting, stopping, and restarting a service is just as easy:

srv stop name-of-service
srv start name-of-service
srv restart name-of-service

Updating a service pulls updates for a Git repository (if applicable), pulls the latest Docker image, updates dependencies, and restarts the application:

srv update name-of-service

You can see logs for a service using srv logs name-of-service.

To run a docker compose exec command for a specific service, you can use srv exec name-of-service <arguments>. This is necessary as srv defines certain environment variables that are required for running docker compose commands. Note that the name of the Compose service will still need to be specified in the argments. (The equivalent for docker compose run is srv run name-of-service.)

Special Service: GitHub Webhook Handler

GitHub Webhook Handler is used to process webhooks from GitHub in order to update services automatically. It is not run via Docker, but defined as a special service with the name webhook-handler and run through Deno. Its repository is pulled on srv init webhook-handler and it supports the other commands above as well. It has three configuration files:

• ~/configs/webhook-handler.meta.json: Meta configuration for proxy and Git repo.
• ~/configs/webhook-handler.json: Configuration for the service itself (will be symlinked into the repo as config.json).
• ~/secrets/WEBHOOK_SECRET: File containing the webhook secret required in GitHub Webhook Handler (will be provided as environment variable).

Note that since we're using Docker for all services, using the push event is not advisable as the Docker container for that push will not be deployed yet. Instead, it is possible to use the workflow_run event for the completed GitHub workflow that updates the Docker container. For example:

{
  "repository": "gbv/jskos-server",
  "command": "srv update jskos-server-dev",
  "event": "workflow_run",
  "action": "completed",
  "filter": {
    "body.workflow_run.head_branch": "dev",
    "body.workflow_run.path": ".github/workflows/docker.yml",
    "body.workflow_run.conclusion": "success"
  }
}

Note that it is not possible to pick out which workflows trigger the workflow_run event, so you will get unmatched triggers regularly. For this reason, GitHub Webhook Handler should be configured with "verbosity": "verbose" instead of "verbosity": "all".

srv Script Dependencies

Deno will automatically download and cache all dependency when srv is first run.

In order to cache dependencies ahead of time, run:

cd src; deno cache --reload --lock=deno.lock server.ts

In order to update the dependencies (and therefore the lockfile), run:

cd src; deno cache --lock=deno.lock --lock-write server.ts

Make sure everything still works with the updated dependencies, then commit the updated deno.lock.

Data Management for JSKOS Server Instances

Data imports and resets for JSKOS Server instances can be managed through the data script. Run data --help for instructions.

The basic usage is: data <command> <service> <arguments for jskos-server import script> where <command> is either "import" or "reset" and <service> is any of the services (defined in the services/ subfolder) that includes a JSKOS Server instance.

Note that local files will be mounted into the container when running the import script. The file argument is expected to be the last argument.

Examples:

data import jskos-server schemes my-schemes.ndjson
data import jskos-server concordances "https://coli-conc.gbv.de/api/concordances/rvk-ddc-4"

Data Management for MongoDB

The easiest way to dump and restore data with MongoDB running in Docker is using a single-file archive via --archive.

Dump Data

srv exec mongo mongo mongodump -d "name-of-database" --forceTableScan --gzip --archive > dump.archive

Restore Data

cat dump.archive | srv exec mongo -iT mongo mongorestore --gzip --nsFrom="name-of-database.*" --nsTo="new-name-of-database-dev.*" --archive

Leave out --nsFrom and --nsTo if the database name should stay the same. Add --drop if you would like to drop the tables before import.

Access MongoDB from the outside

The MongoDB is not accessible from the outside. However, its port (default port 27017) is forwarded to localhost, so to connect to it from the outside, you could set up an SSH tunnel for port 27017.

Other

Folder Structure

• .config/docker/daemon.json - Docker daemon configuration
• bin/
  • bin/autocompletion.sh - Bash autocompletion for srv script
  • bin/srv - Symlink for srv script (links to src/server.ts)
• configs/ - Folder for configuration files
  • configs/webhook-handler.meta.json - Proxy configuration for webhook handler
  • configs/webhook-handler.json - Actual configuration for webhook handler
• data/ - Folder with persistent data for Docker containers
• secrets/ - Folder for secrets; its contents (except for README.md) are not part of the repo
• services/ - Folder for services; one subfolder for each service
• src/ - Source code for srv script (TypeScript, run with Deno)
• .bashrc/.bash_profile - Bash configuration and paths
• .gitignore - Files ignored by Git; note that by default, all files are ignored because we expect this repo to be checked out into the home folder
• README.md - The file you are currently reading
• SETUP.md - Server setup instructions

VSCode Setup

Install the Deno extension and set up the workspace (once) by running the Deno: Initialize Workspace Configuration command.

Restrict Access via Basic Authentication

Sometimes, it is necessary to restrict access to a certain service with basic authentication. First, we need another dependency if it's not yet installed: sudo apt install apache2-utils. Then set up a custom vhost configuration and the password file:

mkdir -p ~/configs/vhost.d
mkdir -p ~/secrets/htpasswd
htpasswd -cb ~/secrets/htpasswd/my-service some_username some_password

For the custom vhost configuration, substitute VIRUTAL_HOST and VIRTUAL_PATH in the following command:

touch ~/configs/vhost.d/VIRTUAL_HOST_$(echo -n "VIRTUAL_PATH" | sha1sum | awk '{ print $1 }')_location

Add the following content (with your editor of choice), adjusting my-service as above:

auth_basic "My Service";
auth_basic_user_file /etc/nginx/htpasswd/my-service;

Add bind volumes to the nginx container in ~/services/nginx/docker-compose.yml:

...
    volumes:
      - /run/user/$UID/docker.sock:/tmp/docker.sock:ro
      - $HOME/configs/vhost.d:/etc/nginx/vhost.d:ro
      - $HOME/secrets/htpasswd:/etc/nginx/htpasswd:ro
...

Finally, restart the proxy:

srv restart nginx

Serving Static Files

In order to serve static files under a certain sub-path, create a new service (e.g. static-test) with a docker-compose.yml file like this:

services:
  static-test:
    image: lscr.io/linuxserver/nginx
    volumes:
      # Depending on what kind of static files are served and whether they are part of the repo
      # nginx www data
      - $DATA/static-test:/config/www
      # Required if using fancyindex module
      - $CONFIGS/nginx-fancyindex-theme.conf:/config/nginx/site-confs/default.conf
      - $DATA/nginx-fancyindex-theme/Nginx-Fancyindex-Theme-light:/config/Nginx-Fancyindex-Theme-light
    environment:
      - VIRTUAL_HOST=coli-conc.gbv.de
      - VIRTUAL_PATH=/test/
      - VIRTUAL_DEST=/
    restart: unless-stopped

networks:
  default:
    external: true
    name: nginx

Then start it like any other service with srv init static-test.

Footnotes

1. If VIRTUAL_PATH is set, but VIRTUAL_DEST isn't, the requests forwarded to the application will include the whole path. This means that if an application listens to the root path /, VIRTUAL_DEST NEEDS to be set to / as well for the application to work (which should be the case for most APIs). Another caveat is that when VIRTUAL_PATH does not end on a slash, requests to that path with a slash appended will result in a double slash. In most cases, it is better to end VIRTUAL_PATH in a slash which adds a 301 redirect from the non-slash version. ↩