# kosync-rs

`kosync-rs` is a self-contained Rust replacement for
`koreader/koreader-sync-server`. It keeps the KOReader sync API compatible while
replacing the old Redis, OpenResty/nginx, Lua/Gin, and runit stack with one
binary and one SQLite database.

Compatibility target:

- Upstream checkout: `../koreader-sync-server`
- Upstream commit: `597e0648be0894c535a222f192d7bd583fb3b2dc`
- Target platforms: Linux `amd64` and Linux `aarch64`

## Quick start

```sh
docker compose up -d
curl -k -H "Accept: application/vnd.koreader.v1+json" https://127.0.0.1:7200/healthcheck
```

The compose file stores data in `./data/kosync.sqlite3`, enables user
registration, exposes HTTPS on `7200`, and exposes plain HTTP on `17200` for
reverse proxies.

The default compose file uses the published multi-arch image
`sodium/kosync-rs:v2.1.1`, which supports Linux `amd64` and `aarch64`.

## Binary usage

```sh
kosync-rs serve
kosync-rs init-db --db ./data/kosync.sqlite3
kosync-rs healthcheck --url https://127.0.0.1:7200/healthcheck --insecure
```

Useful environment variables:

```text
KOSYNC_DB=./data/kosync.sqlite3
KOSYNC_HTTP_ADDR=0.0.0.0:17200
KOSYNC_HTTPS_ADDR=0.0.0.0:7200
KOSYNC_TLS=auto
KOSYNC_TLS_CERT=/path/to/cert.pem
KOSYNC_TLS_KEY=/path/to/key.pem
ENABLE_USER_REGISTRATION=true
RUST_LOG=info
```

`ENABLE_USER_REGISTRATION` matches the old server: registration is enabled only
when the value is exactly `true` or `1`.

## API

Implemented routes:

```text
POST /users/create
GET  /users/auth
PUT  /syncs/progress
GET  /syncs/progress/:document
GET  /healthcheck
```

Authenticated routes use:

```text
x-auth-user: <username>
x-auth-key: <client key>
```

The server stores and compares the auth key exactly as supplied, matching the
original implementation.

## Migrating from the old Docker container

Keep the old container running while importing. The old Redis usually listens
on `127.0.0.1:6379` inside that container, so the helper script joins the old
container's network namespace.

```sh
scripts/import-from-old-redis.sh \
  --old-container kosync \
  --sqlite ./data/kosync.sqlite3 \
  --image sodium/kosync-rs:v2.1.1
```

Then stop the old container and start the new compose stack:

```sh
docker stop kosync
docker compose up -d
```

Export SQLite data back to the old Redis format:

```sh
scripts/export-to-old-redis.sh \
  --old-container kosync \
  --sqlite ./data/kosync.sqlite3 \
  --image sodium/kosync-rs:v2.1.1
```

The export script will not flush Redis unless `--flush-target` is passed.

## Backups

SQLite backup:

```sh
sqlite3 ./data/kosync.sqlite3 ".backup './data/kosync-backup.sqlite3'"
```

Portable JSON backup:

```sh
kosync-rs export-json --db ./data/kosync.sqlite3 --output backup.json
kosync-rs import-json --db ./data/kosync.sqlite3 --input backup.json
```

## License

This project is intended to be compatible with the AGPL-3.0 upstream server and
is licensed as AGPL-3.0-or-later.