Update contribution guide and add CONTRIBUTING.md (#667)

CONTRIBUTING.md

@@ -0,0 +1,3 @@
+## 请参见[参与我们](https://docs.rsshub.app/joinus/)
+
+## Please refer to [Join Us](https://docs.rsshub.app/en/joinus/)

docs/en/joinus/README.md

@@ -18,6 +18,8 @@ We welcome all pull requests. Suggestions and feedback are also welcomed [here](
 
 ## Write the script
 
+RSSHub provides 3 methods for acquiring data, these methods are sorted by **recommended**:
+
 ### Access the target data source API
 
 Use [axios](https://github.com/axios/axios) to access the target data source API, assign the acquired title, link, description and datetime to ctx.state.data (refer to Data for the list of parameters) , typically it looks like this: [/routes/bilibili/bangumi.js](https://github.com/DIYgod/RSSHub/blob/master/routes/bilibili/bangumi.js)
@@ -26,6 +28,16 @@ Use [axios](https://github.com/axios/axios) to access the target data source API
 
 If an API is not provided, data need to be scraped from HTML. Use [axios](https://github.com/axios/axios) to acquire the HTML and then use [cheerio](https://github.com/cheeriojs/cheerio) for scraping the relevant data and assign them to ctx.state.data, typically it looks like this: [/routes/jianshu/home.js](https://github.com/DIYgod/RSSHub/blob/master/routes/jianshu/home.js)
 
+### Page rendering
+
+::: tip tip
+
+This method is comparatively less performant and consumes more resources, only use when necessary or your pull requests might be rejected.
+
+:::
+
+Some websites provides no API and pages require rendering too, use [puppeteer](https://github.com/GoogleChrome/puppeteer) render the pages via Headless Chrome and then use [cheerio](https://github.com/cheeriojs/cheerio) for scraping the relevant data and assign them to ctx.state.data, typically it looks like this: [/routes/sspai/series.js](https://github.com/DIYgod/RSSHub/blob/master/routes/sspai/series.js)
+
 ### Enable caching
 
 All routes has a default cache expiry time set in `config.js`, it should be increased when the data source is not subject to frequent updates.

docs/joinus/README.md

@@ -18,13 +18,25 @@ sidebar: auto
 
 ## 编写脚本
 
+RSSHub 支持三种获取数据的办法, 方法按 **「推荐优先级」** 排列:
+
 ### 从接口获取数据
 
 使用 [axios](https://github.com/axios/axios) 请求接口, 然后把获取的标题、链接、描述、发布时间等数据赋值给 ctx.state.data (每个字段的含义在下面说明) , 可以直接看这个典型的例子: [/routes/bilibili/bangumi.js](https://github.com/DIYgod/RSSHub/blob/master/routes/bilibili/bangumi.js)
 
 ### 从 HTML 获取数据
 
-有时候数据是写在 HTML 里的, 没有接口供我们调用, 这时候可以使用 [axios](https://github.com/axios/axios) 请求 HTML 数据, 然后使用 [cheerio](https://github.com/cheeriojs/cheerio) 解析 HTML, 再把数据赋值给 ctx.state.data, 可以直接看这个典型的例子: [/routes/jianshu/home.js](https://github.com/DIYgod/RSSHub/blob/master/routes/jianshu/home.js)
+有时候数据是写在 HTML 里的, **没有接口供我们调用**, 这时候可以使用 [axios](https://github.com/axios/axios) 请求 HTML 数据, 然后使用 [cheerio](https://github.com/cheeriojs/cheerio) 解析 HTML, 再把数据赋值给 ctx.state.data, 可以直接看这个典型的例子: [/routes/jianshu/home.js](https://github.com/DIYgod/RSSHub/blob/master/routes/jianshu/home.js)
+
+### 渲染页面获取数据
+
+::: tip 提示
+
+由于此方法性能较差且消耗较多资源, 使用前请确保以上两种方法无法获取数据, 不然将导致您的 pull requests 被拒绝!
+
+:::
+
+部分网站**没有接口供调用, 且页面需要渲染**才能获取正确的 HTML, 这时候可以使用 [puppeteer](https://github.com/GoogleChrome/puppeteer) 通过 Headless Chrome 渲染页面, 然后使用 [cheerio](https://github.com/cheeriojs/cheerio) 解析返回的 HTML, 再把数据赋值给 ctx.state.data, 可以直接看这个典型的例子: [/routes/sspai/series.js](https://github.com/DIYgod/RSSHub/blob/master/routes/sspai/series.js)
 
 ### 使用缓存