Generate JSON response on server with JsonArray and single fields - php

Question

I am trying to build a JSON response from my server side, but it is not working as expected.
It is probably something simple but, I am not so good at PHP...
The basic expected response is a JSON with a single JsonArray and some other fields, for that, the relevant piece of code is shown here:
Sample of expected JSON response:
{
"pageNr": 2
"totalPages":28
"products":[
{
"user_name":"testUser001",
"product_ID":"4756373abdhg"
},
{
"user_name":"testUser002",
"product_ID":"475ggdfghghg"
},
{
"user_name":"testUser003",
"product_ID":"47466gdgbdhg"
},
{
"user_name":"testUser004",
"product_ID":"4000nfaergeb"
},
{
"user_name":"testUser005",
"product_ID":"adfer73abdhg"
}
]
}
Basic PHP code used to generate desired JSON (among sql query and other things):
$res = array();
$res2 = array();
while($r = mysqli_fetch_assoc($query2)) {
$res["user_name"] = $r["user_name"];
$res["product_ID"] = $r["prod_ID"];
array_push($res2,$res);
}
$response = ['pageNr' => $page];
$response = ['totalPages' => $totalPages];
$response = ['products' => $res2];
Response that this code is generating on Postman:
{
"products":[
{
"user_name":"testUser001",
"product_ID":"4756373abdhg"
},
{
"user_name":"testUser002",
"product_ID":"475ggdfghghg"
},
{
"user_name":"testUser003",
"product_ID":"47466gdgbdhg"
},
{
"user_name":"testUser004",
"product_ID":"4000nfaergeb"
},
{
"user_name":"testUser005",
"product_ID":"adfer73abdhg"
}
]
}
So, for some reason the JSON response is not accepting more fields pageNrand totalPages.
What is wrong here?.

Answer 1

Each assignment overwrites your array. You need to update it instead:
$res = array();
$res2 = array();
while($r = mysqli_fetch_assoc($query2)) {
$res["user_name"] = $r["user_name"];
$res["product_ID"] = $r["prod_ID"];
array_push($res2,$res);
}
$response = [];
$response['pageNr'] = $page;
$response['totalPages'] = $totalPages;
$response['products'] = $res2;

Answer 2

Try;
$res = array();
$res2 = array();
while($r = mysqli_fetch_assoc($query2)) {
$res["user_name"] = $r["user_name"];
$res["product_ID"] = $r["prod_ID"];
array_push($res2,$res);
}
$response .= ['pageNr' => $page];
$response .= ['totalPages' => $totalPages];
$response .= ['products' => $res2];