werkator/docs/deployment.md

# GitTally Deployment

This document describes how to run GitTally as a permanent service.
The recommended setup is a systemd user service behind an existing reverse proxy.
By default GitTally does not manage nginx or TLS certificates itself; it relies on the host's existing web server and certbot.
For hosts without one, an opt-in managed nginx/TLS container is available, see [Hosts Without a Reverse Proxy](#hosts-without-a-reverse-proxy-managed-nginxtls).

## Prerequisites

- Linux with systemd.
- Java runtime (JRE 21) — or none, when using the self-contained runtime bundle, see [Hosts Without a Java Runtime](#hosts-without-a-java-runtime-runtime-bundle).
- `git` CLI on the `PATH`.
- `docker` CLI on the `PATH`, only if any branch uses `docker.enabled` (see [configuration.md](configuration.md)).
- A checked-out working tree of the repository to watch, with a remote named `origin`.

## Jar Location Convention

Build the executable jar once:

```bash
./gradlew build
ls build/libs/gittally.jar
```

Copy the jar to a stable path outside any watched repository, by convention `~/bin/gittally.jar`:

```bash
mkdir -p ~/bin
cp build/libs/gittally.jar ~/bin/gittally.jar
```

The systemd unit generated below points at the jar that was used to run `init --systemd`.
So always run it via the stable path, not via `build/libs/`.

## Install the Service

Initialize GitTally in the repository to watch (see [bootstrapping.md](bootstrapping.md) for details):

```bash
cd /path/to/repo
java -jar ~/bin/gittally.jar init
# fill in git.account and git.token in .git/gittally/.gittally.yml
# review .gittally.yml
```

Generate the systemd user unit:

```bash
java -jar ~/bin/gittally.jar init --systemd
```

This writes `.git/gittally/gittally-<repo-name>.service`, `.git/gittally/gittally.env`, and the nightly Docker cleanup units (`gittally-docker-prune.service`/`.timer`), and prints the install commands:

```bash
ln -sf /path/to/repo/.git/gittally/gittally-<repo-name>.service ~/.config/systemd/user/gittally-<repo-name>.service
ln -sf /path/to/repo/.git/gittally/gittally-docker-prune.service ~/.config/systemd/user/gittally-docker-prune.service
ln -sf /path/to/repo/.git/gittally/gittally-docker-prune.timer ~/.config/systemd/user/gittally-docker-prune.timer
systemctl --user daemon-reload
systemctl --user enable --now gittally-<repo-name>.service
systemctl --user enable --now gittally-docker-prune.timer
```

The unit runs `java -jar ~/bin/gittally.jar server` with the repository as working directory and `Restart=always`.
The unit name contains the repository name, so several repositories can be served by one host, each with its own service and port.

### Nightly Docker Cleanup

The `gittally-docker-prune.timer` runs `docker system prune -af` every night at 02:00 (host time), before the usual auto-build slots.
It removes stopped containers, unused images, unused networks, and dangling build cache, so nightly builds start from freshly built images.
Unlike the legacy cleanup it does **not** prune volumes — the per-repository Gradle cache volumes survive.
The units are host-global (no repository name): with several GitTally instances on one host, every `init --systemd` generates the same files and the symlinks coincide.
On hosts without a `docker` CLI the service is skipped, not failed (`ExecCondition`).
`Persistent=true` catches up a missed run after downtime.

Expect a burst of builds right after the very first start: in a fresh clone every origin branch counts as new, so each branch with commits younger than `watcher.newBranchMaxAge` (default 5d) is built once — one build per branch, executed serially up to `builds.maxConcurrent`.
Lower `watcher.newBranchMaxAge` before the first start, or enable `requirePullRequest`, to limit the initial backlog.

User services stop at logout unless lingering is enabled once per user:

```bash
loginctl enable-linger "$USER"
```

## Operating the Service

```bash
systemctl --user status gittally-<repo-name>.service     # state and last log lines
journalctl --user -u gittally-<repo-name>.service -f     # follow the log
systemctl --user restart gittally-<repo-name>.service    # restart (e.g. after config changes)
systemctl --user stop gittally-<repo-name>.service       # stop
```

To update GitTally, replace `~/bin/gittally.jar` and restart the service.

## Environment File

`.git/gittally/gittally.env` is loaded by the unit as `EnvironmentFile`.
It only tunes the JVM process, e.g. `JAVA_OPTS=-Xmx256m`.
All GitTally configuration lives in the YAML files described in [configuration.md](configuration.md), not in environment variables.
`init --systemd` never overwrites an existing environment file.

## Reverse Proxy (nginx)

Bind GitTally to localhost — the default since v0.9.9 — and set the public URL in `.gittally.yml`:

```yaml
server:
  bindAddress: 127.0.0.1
  port: 18080
  publicBaseUrl: "https://ci.example.org/"
```

`publicBaseUrl` is used for all links posted to Gitea, so it must be the externally reachable URL.

Add a `server` block to the host's nginx:

```nginx
server {
    listen 443 ssl;
    server_name ci.example.org;

    ssl_certificate     /etc/letsencrypt/live/ci.example.org/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/ci.example.org/privkey.pem;

    location / {
        proxy_pass http://127.0.0.1:18080;
        proxy_set_header Host $host;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    }
}
```

Obtain and renew the certificate with the host's existing certbot, e.g.:

```bash
sudo certbot --nginx -d ci.example.org
```

This replaces the legacy script's managed nginx/Let's Encrypt Docker container for hosts that have their own web server.

## Hosts Without a Java Runtime (Runtime Bundle)

Some hosts provide git and Docker but no Java runtime and no way to install one, e.g. Hostsharing container servers.
For these, GitTally ships as a self-contained runtime bundle: a jlink-trimmed JRE, `gittally.jar`, and a launcher script in one tarball (ADR 0006).

Build the bundle on a Linux x86_64 machine whose glibc is not newer than the target's:

```bash
./gradlew runtimeBundle
ls build/distributions/gittally-runtime-linux-x64.tar.gz
```

Copy and unpack it on the target host, by convention to `~/opt/gittally`:

```bash
scp build/distributions/gittally-runtime-linux-x64.tar.gz user@host:/tmp/
ssh user@host 'mkdir -p ~/opt && tar -xzf /tmp/gittally-runtime-linux-x64.tar.gz -C ~/opt'
```

Then use `~/opt/gittally/bin/gittally` wherever this document says `java -jar ~/bin/gittally.jar`:

```bash
cd /path/to/repo
~/opt/gittally/bin/gittally init
~/opt/gittally/bin/gittally init --systemd
```

`init --systemd` detects the bundle automatically: the generated unit's `ExecStart` points at the bundle's `jre/bin/java` and `lib/gittally.jar`, so the install commands printed by `init --systemd` work unchanged.
`JAVA_OPTS` from the environment file applies as usual.

To update GitTally, stop the service, unpack the new bundle over `~/opt/gittally`, and restart the service.

## Hosts Without a Reverse Proxy (Managed nginx/TLS)

Some hosts provide Docker but no root access and no host web server, e.g. Hostsharing managed container environments.
For these, GitTally can manage its own nginx+certbot Docker container (ADR 0005).
This is opt-in; where a host web server exists, prefer the reverse-proxy setup above.

Enable it in the server section of the configuration:

```yaml
server:
  port: 18080
  nginx:
    enabled: true
    serverName: ci.example.org
    httpPort: 8080
    httpsPort: 8443
    letsencryptEmail: admin@example.org
```

On server start, GitTally writes the nginx configuration, starts a labelled nginx container publishing `httpPort` and `httpsPort`, obtains a Let's Encrypt certificate via a certbot container (webroot mode), and restarts nginx with the full HTTPS configuration.
A renewal check runs daily; certificates and nginx state persist in `server.nginx.stateDir` across restarts.
On shutdown the container is removed.
All nginx and certificate failures are non-fatal warnings — the plain HTTP server keeps running without the proxy.

`serverName` must be a public DNS name pointing at the host, reachable from the internet on port 80/443 (directly or via a port forward to `httpPort`/`httpsPort`), otherwise the ACME challenge fails.
The nginx container cannot reach `localhost` of the host, so the proxy upstream defaults to `serverName`; set `server.nginx.upstreamHost` if the host is reachable under a different name from inside containers.
With the managed nginx, set `server.bindAddress: 0.0.0.0` explicitly (or an address reachable from the Docker network) — the default `127.0.0.1` makes GitTally unreachable for the proxy container.
See [configuration.md](configuration.md) for all `server.nginx.*` keys.