# OceanBase LogProxy

OceanBase LogProxy (CE) is a proxy service of [OceanBase CE](https://github.com/oceanbase/oceanbase). It is a part of [OMS](https://www.oceanbase.com/product/oms), and it can establish and manage connections with OceanBase for incremental log reading even with a isolated network.

## Instructions before use

### Version compatibility

LogProxy is based on [libobcdc](https://github.com/oceanbase/oceanbase/tree/master/src/logservice/libobcdc) (former `liboblog`), which is packaged in `oceanbase-ce-cdc` rpm file from `v4.0.0`. You can get it from the [software center](https://www.oceanbase.com/softwarecenter) or [official mirrors](https://mirrors.aliyun.com/oceanbase/community/stable/el/).

For `v1.1.0` or later versions of LogProxy, we no longer provide the rpm file for installation. Users should use the compressed package at [software center](https://www.oceanbase.com/softwarecenter) or [releases page](https://github.com/oceanbase/oblogproxy/releases), which already has a suitable `libobcdc` built in, so users no longer need to install `libobcdc` manually.

Please check the release note for detailed version compatibility information.

#### For OceanBase CE 3.x Users

The `libobcdc` or `liboblog` was packaged in `oceanbase-ce-devel` rpm file before `v4.0.0`, and users need to install it manually before deploy the LogProxy service.

The version correspondence between libobcdc and LogProxy is as follows.

| libobcdc | LogProxy |
|----------|----------|
| 3.1.1    | 1.0.0    |
| 3.1.2    | 1.0.1    |
| 3.1.3    | 1.0.2    |
| 3.1.4    | 1.0.3    |

### Installation

LogProxy service doesn't need params about OceanBase cluster to get started, one LogProxy can subscribe to multiple OceanBase clusters at the same time, and the connection configuration is passed from the client.

LogProxy will use a lot of memory, so it is strongly recommended to deploy it separately from the OceanBase server.

## Getting started

### Install

You can install a released version of LogProxy or build it from the source code.

#### Install a released version

If you want to install a released version, you can use the compressed package at the release page or software center. Here we take `/usr/local/oblogproxy` as the deployment directory. 

```bash
wget https://github.com/oceanbase/oblogproxy/releases/download/v1.1.1/oblogproxy-ce-for-4x-1.1.1-20230418115957.tar.gz
tar -zxvf oblogproxy-ce-for-4x-1.1.1-20230418115957.tar.gz -C /usr/local
```

#### Build from source code

See [How to build](docs/build.md).

### Configure

For security reasons, LogProxy needs to configure the username and password of a certain user, which must be a sys tenant user of the OceanBase to connect with. Note that the username here should not contain cluster name or tenant name.

You can configure the username and password by one of the following ways:
- Add it to local conf at `conf/conf.json`.
- Set it in the client params. See the [client doc](https://github.com/oceanbase/oblogclient/blob/master/docs/quickstart/logproxy-client-tutorial.md) for details.

#### Add it to local conf

Firstly, set the libobcdc path to environment, here we use the builtin libobcdc in the deployment directory.

```bash
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/oblogproxy/libobcdc
```

Get the encrypted username and password.

```bash
./bin/logproxy -x username
./bin/logproxy -x password
```

Then add the outputs to `ob_sys_username` and `ob_sys_password` at `conf/conf.json`.

### Start

You can start the service by the following command.

```bash
bash ./run.sh start
```

Then you can use [oblogclient](https://github.com/oceanbase/oblogclient) to subscribe the log data from LogProxy, and the service is bind to port `2983` by default. 

The service log of LogProxy is located at `logs/`, and the service log of LogReader (task thread) is located at `run/{client-id}/logs/`.

## Licencing

OceanBase Database is under MulanPubL - 2.0 license. You can freely copy and use the source code. When you modify or distribute the source code, please obey the MulanPubL - 2.0 license.

## Contributing

Contributions are warmly welcomed and greatly appreciated. Here are a few ways you can contribute:
- Raise us an [issue](https://github.com/oceanbase/oblogproxy/issues).
- Submit Pull Requests. 

## Support

In case you have any problems when using OceanBase LogProxy, welcome reach out for help:
- [GitHub Issue](https://github.com/oceanbase/oblogproxy/issues)
- [Official Website](https://open.oceanbase.com/)