如何在Angular2服务中进行递归http调用以预取数据？

Question

I've got an Angular service which fetches records from an open API. The API limits me to fetching 100 records at a time and I won't know how many records there are to fetch until I retrieve the first batch.

The format of the API response looks like this:

{
    "offset": 0,
    "limit": 100,
    "total": 140,
    "count": 100,
    "results": []
}

I don't know how many calls I need to make to the API until after I fetch the first page and get the "total" value from the response.

Any idea how to accomplish this?

Thanks!

Answer 1

Not angular an specific problem, so no (real) code here.

In any language; you can do something like this: (ie call the getData function from the function that receives the data)

var limit = 100;
var offset = 0;

function getData(offset) {
 someHTTPcall('http://...?offset='+offset)
 mapData(response)
}

function mapData(result) {
 myData.push(response.results)
 if (myData.length < response.total) {
   getData(myData.lenght +1)
 }
}