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[Chinese](fault-injection-cn.md)

## Name

Fault injection plugin, this plugin can be used with other plugins and will be executed before other plugins.  The `abort` attribute will directly return the user-specified http code to the client and terminate the subsequent plugins. The `delay` attribute will delay a request and execute subsequent plugins.


## Attributes

|Name          |Requirement  |Description|
|------- |-----|------|
|abort.http_status|required|user-specified http code returned to the client|
|abort.body|optional|response data returned to the client|
|delay.duration|required|delay time(can be decimal)|

Note: `abort` and `delay` must have at least one.

## How To Enable

#### Enable the plugin

1: enable the fault-injection plugin for a specific route and specify the abort attribute：

```shell
curl http://127.0.0.1:9080/apisix/admin/routes/1 -X PUT -d '
{
    "plugins": {
       "fault-injection": {
           "abort": {
              "http_status": 200,
              "body": "Fault Injection!"
           }
       }
    },
    "upstream": {
       "nodes": {
           "127.0.0.1:1980": 1
       },
       "type": "roundrobin"
    },
    "uri": "/hello"
}'
```

Test plugin：

```shell
$ curl http://127.0.0.1:9080/hello -i
HTTP/1.1 200 OK
Date: Mon, 13 Jan 2020 13:50:04 GMT
Content-Type: text/plain
Transfer-Encoding: chunked
Connection: keep-alive
Server: APISIX web server

Fault Injection!
```

> http status is 200 and the response body is "Fault Injection! " indicate that the plugin is enabled.

2: Enable the `fault-injection` plugin for a specific route and specify the `delay` attribute:

```shell
curl http://127.0.0.1:9080/apisix/admin/routes/1 -X PUT -d '
{
    "plugins": {
       "fault-injection": {
           "delay": {
              "duration": 3
           }
       }
    },
    "upstream": {
       "nodes": {
           "127.0.0.1:1980": 1
       },
       "type": "roundrobin"
    },
    "uri": "/hello"
}'
```

Test plugin：

```shell
$ time curl http://127.0.0.1:9080/hello -i
HTTP/1.1 200 OK
Content-Type: application/octet-stream
Content-Length: 6
Connection: keep-alive
Server: APISIX web server
Date: Tue, 14 Jan 2020 14:30:54 GMT
Last-Modified: Sat, 11 Jan 2020 12:46:21 GMT

hello

real    0m3.034s
user    0m0.007s
sys     0m0.010s
```


## Disable Plugin

Remove the corresponding JSON in the plugin configuration to disable the plugin immediately without restarting the service:

```shell
curl http://127.0.0.1:9080/apisix/admin/routes/1 -X PUT -d '
{
    "uri": "/hello",
    "plugins": {},
    "upstream": {
        "type": "roundrobin",
        "nodes": {
            "127.0.0.1:1980": 1
        }
    }
}'
```

The plugin has been disabled now.