我使用以下内容来获取帖子
http://demo.wp-api.org/wp-json/wp/v2/posts
默认情况下,这会给我 10 个帖子,文档中提到了这一点。
但我想要所有帖子而不必跟踪分页。
这可能吗?
如果没有,我可以运行 JavaScript 循环来获取所有帖子吗?
谢谢。
最佳答案
解决此问题的一种方法是使用 RxJS
我们将构建一个小型 Observable 流,它将:
- 输出所有发布数据
- 不要强制我们事先知道帖子总数或页数
- 不强制在分页上下文中跟踪“我们所处的位置”
我们将使用的库:
您的环境和用例会有所不同,在本示例中,我将处于 Node 环境中。
/**
* This will get all posts from a default WordPress REST API
* First we see how many pages there are
* Then we make subsequent XHR requests (via Axios)
* That paginate through every page of posts
*/
// Importing Axios for simple AJAX request
const axios = require('axios')
// Importing RxJS @ v6.0.0-alpha.3
const { Observable, from, range } = require('rxjs')
const { switchMap, concatMap } = require('rxjs/operators')
const endpoint = 'http://demo.wp-api.org/wp-json/wp/v2/posts'
/**
* This sets up the initial request and the Observable stream
* In the return from the endpoint, the Axios request headers will have x-wp-totalpages,
* which gives us... the total pages of posts ;)
*/
const posts$ = Rx.Observable.from(axios.get(endpoint))
/**
* We now know the total number of pages,
* so we'll switch to a new Observable that is just a range of numbers
* We'll start with 1, and end with whatever the total number of pages is
* This gives us a stream of 1--n--n--n... (example: 1, 2, 3, 4...)
*/
.switchMap((
{ headers }, // using ES6 function header destructuring and arrow functions here
) => Rx.Observable.range(1, Number(headers['x-wp-totalpages'])))
/**
* We can now paginate through all posts, getting 10/page
* concatMap will fire off a request, waits until it completes, and then fire the next one
* In each subsequent firing, we ask for the next page of posts
*/
.concatMap(page =>
axios.get(endpoint, {
params: {
page,
},
}),
)
.subscribe(
// data here is an Array of WordPress Posts, tacking .length shows us how many per page we are getting
({ data }) => console.log(data.length),
err => console.log('Oh no, an error!', err),
)
资源
- RunKit example with the code above (唯一的区别是在 RunKit 示例中导入 RxJS v5,因为 v6 尚不可用,但此示例的 API 没有 不同)
- RxJS In Depth - Ben Lesh (视频,主要维护者对 RxJS 的良好介绍)
- The introduction to Reactive Programming you've been missing (@andrestaltz RxJS 介绍的最佳文本资源)
- https://www.learnrxjs.io/
- Destructuring objects as function parameters in ES6
- Arrow Functions on MDN (检查基本和高级语法)
关于WordPress Rest API 获取所有帖子,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/48494711/