apisix/doc/stream-proxy.md

<!--
#
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
-->

[Chinese](stream-proxy-cn.md)

# Stream Proxy

TCP is the protocol for many popular applications and services, such as LDAP, MySQL, and RTMP. UDP (User Datagram Protocol) is the protocol for many popular non-transactional applications, such as DNS, syslog, and RADIUS.

APISIX can dynamic load balancing TCP/UDP proxy. In Nginx world, we call TCP/UDP proxy to stream proxy, we followed this statement.

## How to enable Stream proxy?

Setting the `stream_proxy` option in `conf/config.yaml`, specify a list of addresses that require dynamic proxy.
By default, no any stream proxy is enabled.

```
apisix:
  stream_proxy:                 # TCP/UDP proxy
    tcp:                        # TCP proxy address list
      - 9100
      - 127.0.0.1:9101
    udp:                        # UDP proxy address list
      - 9200
      - 127.0.0.1:9211
```

## How to set route?

Here is a mini example:

```shell
curl http://127.0.0.1:9080/apisix/admin/stream_routes/1 -X PUT -d '
{
    "remote_addr": "127.0.0.1",
    "upstream": {
        "nodes": {
            "127.0.0.1:1995": 1
        },
        "type": "roundrobin"
    }
}'
```

It means APISIX will proxy the request to `127.0.0.1:1995` which the client remote address is `127.0.0.1`.

For more use cases, please take a look at [test case](../t/stream-node/sanity.t).

## More Limit Options

And we can add more limit options to match a route, here is an example:

```shell
curl http://127.0.0.1:9080/apisix/admin/stream_routes/1 -X PUT -d '
{
    "server_addr": "127.0.0.1",
    "server_port": 2000,
    "upstream": {
        "nodes": {
            "127.0.0.1:1995": 1
        },
        "type": "roundrobin"
    }
}'
```

It means APISIX will proxy the request to `127.0.0.1:1995` which the server remote address is `127.0.0.1` and the server port is equal `2000`.