Push Request from a Do while using Guzzle - php

Question

I have a problem with my results array, what I initially intended to have is something like this
$promises = [
'0' => $client->getAsync("www.api.com/opportunities?api=key&page=1fields=['fields']"),
'1' => $client->getAsync("www.api.com/opportunities?api=key&page=2fields=['fields']"),
'2' => $client->getAsync("www.api.com/opportunities?api=key&page=3fields=['fields']")
];
An array of request promises, I will use it because I want to retrieve a collection of data from the API that I am using. This is what the API first page looks like
In my request I want to get page 2,3,4.
This is how page 2 looks like
I made a do while loop on my PHP script but it seems to run an infinite loop
This is how it should work. First I run the initial request then get totalRecordCount = 154 and subtract it to recordCount = 100 if difference is != 0 it run it again and change the $pageNumber and push it to the promises.
This is my function code.Here's my code
function runRequest(){
$promises = [];
$client = new \GuzzleHttp\Client();
$pageCounter = 1;
$globalCount = 0;
do {
//request first and then check if has difference
$url = 'https://api.com/opportunities_dates?key='.$GLOBALS['API_KEY'].'&page='.$pageCounter.'&fields=["fields"]';
$initialRequest = $client->getAsync($url);
$initialRequest->then(function ($response) {
return $response;
});
$initialResponse = $initialRequest->wait();
$initialBody = json_decode($initialResponse->getBody());
$totalRecordCount = $initialBody->totalRecordCount;//154
$recordCount = $initialBody->recordCount;//100
$difference = $totalRecordCount - $recordCount;//54
$pageCounter++;
$globalCount += $recordCount;
array_push($promises,$url);
} while ($totalRecordCount >= $globalCount);
return $promises;
}
$a = $runRequest();
print_r($a); //contains array of endpoint like in the sample above

Answer 1

There is an endless loop because you keep looping when the total record count equals the global count. Page 3 and above have 0 records, so the total will be 154. Replacing the >= with a > will solve the loop.
However, the code will still not work as you expect it to do. For each page, you prepare a request with getAsync() and immediately do a wait(). The then statement does nothing. It returns the response, which it already does by default. So in practice, these are all sync requests.
Given that the page size is constant, you can calculate the pages you need based on the information given on the first request.
function runRequest(){
$promises = [];
$client = new \GuzzleHttp\Client();
$url = 'https://api.com/opportunities_dates?key='.$GLOBALS['API_KEY'].'&fields=["fields"]';
// Initial request to get total record count and page count
$initialRequest = $client->getAsync($url.'&page=1');
$initialResponse = $initialRequest->wait();
$initialBody = json_decode($initialResponse->getBody());
$promises[] = $initialRequest;
$totalRecordCount = $initialBody->totalRecordCount;//154
$pageSize = $initialBody->pageSize;//100
$nrOfPages = ceil($totalRecordCount / $pageSize);//2
for ($page = 2; $page <= $nrOfPages; $page++) {
$promises[] = $client->getAsync($url.'&page='.$page);
}
return $promises;
}
$promises = runRequest();
$responses = \GuzzleHttp\Promise\unwrap($promises);
Note that the function now returns promises and not URLs as strings.
It doesn't matter that the first promise is already settled. The unwrap function will not cause another GET request for page 1, but return the existing response. For all other pages, the requests are done concurrently.