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[Chinese](request-validation-cn.md)

# Summary
- [**Name**](#name)
- [**Attributes**](#attributes)
- [**How To Enable**](#how-to-enable)
- [**Test Plugin**](#test-plugin)
- [**Disable Plugin**](#disable-plugin)
- [**Examples**](#examples)


## Name

`request-validation` plugin validates the requests before forwarding to an upstream service. The validation plugin uses
json-schema to validate the schema. The plugin can be used to validate the headers and body data.

For more information on schema, refer to [JSON schema](https://github.com/api7/jsonschema) for more information.

## Attributes

|Name           |Requirement    |Description|
|---------      |--------       |-----------|
| header_schema |optional       |schema for the header data|
| body_schema   |optional       |schema for the body data|

## How To Enable

Create a route and enable the request-validation plugin on the route:

```shell
curl http://127.0.0.1:9080/apisix/admin/routes/5 -H 'X-API-KEY: edd1c9f034335f136f87ad84b625c8f1' -X PUT -d '
{
    "uri": "/get",
    "plugins": {
        "request-validation": {
            "body_schema": {
                "type": "object",
                "required": ["required_payload"],
                "properties": {
                    "required_payload": {"type": "string"},
                    "boolean_payload": {"type": "boolean"}
                }
            }
        }
    },
    "upstream": {
    	"type": "roundrobin",
    	"nodes": {
        	"127.0.0.1:8080": 1
    	}
    }
}
```

## Test Plugin

```shell
curl --header "Content-Type: application/json" \
  --request POST \
  --data '{"boolean-payload":true,"required_payload":"hello"}' \
  http://127.0.0.1:9080/get
```

If the schema is violated the plugin will yield a `400` bad request.

## Disable Plugin

Remove the corresponding json configuration in the plugin configuration to disable the `request-validation`.
APISIX plugins are hot-reloaded, therefore no need to restart APISIX.

```shell
curl http://127.0.0.1:9080/apisix/admin/routes/5 -H 'X-API-KEY: edd1c9f034335f136f87ad84b625c8f1' -X PUT -d '
{
    "uri": "/get",
    "plugins": {
    },
    "upstream": {
    	"type": "roundrobin",
    	"nodes": {
        	"127.0.0.1:8080": 1
    	}
    }
}
```


## Examples:

**Using ENUMS:**

```shell
"body_schema": {
    "type": "object",
    "required": ["required_payload"],
    "properties": {
            "emum_payload": {
            "type": "string",
            enum: ["enum_string_1", "enum_string_2"]
            default = "enum_string_1"
        }
    }
}
```


**JSON with multiple levels:**

```shell
"body_schema": {
    "type": "object",
    "required": ["required_payload"],
    "properties": {
        "boolean_payload": {"type": "boolean"},
        "child_element_name": {
            "type": "object",
            "properties": {
                "http_statuses": {
                    "type": "array",
                    "minItems": 1,
                    "items": {
                        "type": "integer",
                        "minimum": 200,
                        "maximum": 599
                    },
                    "uniqueItems": true,
                    "default": [200, 201, 202, 203]
                }
            }
        }
    }
}
```