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The control API can be used to

* expose APISIX internal state
* control the behavior of a single isolate APISIX data panel

By default, the control API server is enabled and listens to `127.0.0.1:9090`. You can change it via
the `control` section under `apisix` in `conf/config.yaml`:

```yaml
apisix:
  ...
  enable_control: true
  control:
    ip: "127.0.0.1"
    port: 9090
```

Note that the control API server should not be configured to listen to the public traffic!

## Control API Added via plugin

Plugin can add its control API when it is enabled.
If a plugin adds such a control API, please refer to each plugin's documentation for those APIs.

## Plugin independent Control API

Here is the supported API:

### GET /v1/schema

Introduced since `v2.2`.

Return the jsonschema used by this APISIX instance in the format below:

```json
{
    "main": {
        "route": {
            "properties": {...}
        },
        "upstream": {
            "properties": {...}
        },
        ...
    },
    "plugins": {
        "example-plugin": {
            "consumer_schema": {...},
            "metadata_schema": {...},
            "schema": {...},
            "type": ...,
            "priority": 0,
            "version": 0.1
        },
        ...
    }
}
```

For `plugins` part, only enabled plugins will be returned. Some plugins may lack
of fields like `consumer_schema` or `type`, it is dependended by the plugin's
definition.

### GET /v1/healthcheck

Introduced since `v2.3`.

Return current [health check](health-check.md) status in the format below:

```json
[
    {
        "healthy_nodes": [
            {
                "host": "127.0.0.1",
                "port": 1980,
                "weight": 1
            }
        ],
        "name": "upstream#/upstreams/1",
        "nodes": [
            {
                "host": "127.0.0.1",
                "port": 1980,
                "weight": 1
            },
            {
                "host": "127.0.0.2",
                "port": 1988,
                "weight": 1
            }
        ],
        "src_id": "1",
        "src_type": "upstreams"
    },
    {
        "healthy_nodes": [
            {
                "host": "127.0.0.1",
                "port": 1980,
                "weight": 1
            }
        ],
        "name": "upstream#/routes/1",
        "nodes": [
            {
                "host": "127.0.0.1",
                "port": 1980,
                "weight": 1
            },
            {
                "host": "127.0.0.1",
                "port": 1988,
                "weight": 1
            }
        ],
        "src_id": "1",
        "src_type": "routes"
    }
]
```

Each entry contains fields below:

* src_type: where the health checker comes from. The value is one of `["routes", "services", "upstreams"]`.
* src_id: the id of object which creates the health checker. For example, if Upstream
object with id 1 creates a health checker, the `src_type` is `upstreams` and the `src_id` is `1`.
* name: the name of the health checker.
* nodes: the target nodes of the health checker.
* healthy_nodes: the healthy node known by the health checker.

User can also use `/v1/healthcheck/$src_type/$src_id` can get the status of a health checker.

For example, `GET /v1/healthcheck/upstreams/1` returns:

```json
{
    "healthy_nodes": [
        {
            "host": "127.0.0.1",
            "port": 1980,
            "weight": 1
        }
    ],
    "name": "upstream#/upstreams/1",
    "nodes": [
        {
            "host": "127.0.0.1",
            "port": 1980,
            "weight": 1
        },
        {
            "host": "127.0.0.2",
            "port": 1988,
            "weight": 1
        }
    ],
    "src_id": "1",
    "src_type": "upstreams"
}
```