k6
###


安装::

    $ brew install k6
    $ docker pull loadimpact/k6


说明::

    1. 本地版只没有UI界面
    2. cloud版不能调试本地接口 && 有请求限制 && Pro版收费

.. note:: 注意k6有两个地方登录, 使用不同的用户体系. 一个是官网 https://k6.io 另一个是命令专用 https://app.k6.io




简单实例::

    $ cat script.js
    import http from 'k6/http';
    import { sleep } from 'k6';

    export default function() {   // 注: 这个函数是必须的
      http.get('http://test.k6.io');
      sleep(1);
    }

    使用:
    $ k6 run script.js

    Docker版使用:
    $ docker run -i loadimpact/k6 run - <script.js


    Adding more VUs:
    $ k6 run --vus 10 --duration 30s script.js

code类型::

    // init code

    export default function( {
      // vu code
    }

    init code与vu code的区别:
    init code每个vu只执行一次而vu code在测试时间段内一直运行

options字段::

    import http from 'k6/http';
    import { sleep } from 'k6';
    export let options = {
      vus: 10,
      duration: '30s',
    };
    export default function() {
      http.get('http://test.k6.io');
      sleep(1);
    }

    等同于在命令行执行时增加:
    --vus 10 and --duration 30s

Stages(up/down VUs)::

    import http from 'k6/http';
    import { check, sleep } from 'k6';

    export let options = {
      stages: [        // 这儿有3个阶段
        { duration: '30s', target: 20 },
        { duration: '1m30s', target: 10 },
        { duration: '20s', target: 0 },
      ],
    };

    export default function() {
      let res = http.get('https://httpbin.org/');
      check(res, { 'status was 200': r => r.status == 200 });
      sleep(1);
    }

three execution modes::

    1. Local: on your local machine or a CI server.
    2. Cloud: on cloud infrastructure managed by k6 Cloud.
    3. Clustered: on more than one machine managed by you. Not supported yet.(估计这个会是开源与商业版的区别)