PHP Array Index Error When Fetching Twitch API Data

Other Questions Twitch
1

I’m getting this error message on my site: Notice: Undefined offset: 1 in…

I have a PHP script that should pull channel data from my database and show Twitch stream information. The problem seems to be in the section where I loop through the API response. Here’s my code:

<?php
defined('_JEXEC') or die('Access denied.');
$channelList = $params->get('channels');
$channelsArray = explode(',', $channelList);
$apiUrl = "https://api.twitch.tv/helix/streams?user_login=";
$activeStreams = array();

foreach($channelsArray as $index => $channel){
    $apiUrl .= "&";
    $apiUrl .= $channel;
}
unset($channel);

$response = file_get_contents($apiUrl, 0, null, null);
$data = json_decode($response, true);

// This is where the error occurs
foreach($channelsArray as $index => $channel){
    $streamUrl = $data[$index]['user']['profile_url'];
    $urlParts = explode('/', $streamUrl);
    $username = end($urlParts);
    $streamTitle = $data[$index]['title'];
    $gameCategory = $data[$index]['game_name'];
    $viewerCount = $data[$index]['viewer_count'];
    $description = $data[$index]['description'];
    displayStream($username, $viewerCount, $description, $gameCategory);
    $activeStreams[] = checkStatus($username);
}

unset($channel);
unset($index);

function displayStream($streamer, $viewers, $description, $category)
{
    if ($category == "Counter-Strike 2")
    {
        $gameIcon = "cs2.jpg";
    }
    else {
        $gameIcon = "live.png";
    }
    
    if ($streamer != null)
    {
        echo '&nbsp;<img src="./modules/mod_streamlist/images/'.$gameIcon.'">';
        echo '<a href="https://www.twitch.tv/'.$streamer.'" target="_blank"> <strong>'.$streamer.'</strong></a>';
        echo '&nbsp;(' .$viewers.') - ';
        echo '<strong>'.$description.'</strong> <br>';
    }
}

function checkStatus($user){
    if($user != null){
        return $user;
    }
    else {
        return null;
    }
}
?>

<?php
foreach ($channelsArray as $i => $channel1) {
    foreach($activeStreams as $j => $channel2){
        if($channel1 == $channel2){
            unset($channelsArray[$i]);
        }
    }
}

$offlineCount = count($channelsArray);
$totalStreams = count($activeStreams);

if ($offlineCount == $totalStreams){
    echo '<strong><center>No streams are currently live!</center></strong>';
}
?>

What could be causing this offset error? Any suggestions would be helpful.

2

You’re mixing up array indexes. The Twitch API returns data in $data['data'], not directly indexed by your channel positions. Offline channels won’t show up in the response, so $data[0] might not match $channelsArray[0]. Loop through $data['data'] instead and match by username field.

3

The problem is you’re assuming the API response matches your input array structure. When streams go offline, they just disappear from the response - so your indexing breaks. I hit this same issue building a module for our gaming site. Twitch’s API only returns active streams in the ‘data’ array, so $data[$index] crashes when that index doesn’t exist. Don’t use your channel array indices. Instead, loop through $data['data'] and match streams by ‘user_login’ against your channel names. This handles offline channels without throwing undefined offset errors.

4

I hit this exact problem building a community dashboard with Twitch’s API. Here’s what’s happening: you’re assuming the API response keeps the same order and count as your input channels, but it doesn’t. The API only returns live streams in $data['data'] - not all channels you asked for. Your code thinks $channelsArray[0] matches $data[0], but if your first channel is offline, $data[0] will be whatever channel happens to be live. You need to loop through $data['data'] and use the user_login field to match each stream to the right channel instead of relying on array positions.

5

The offset error arises because the API response does not match the indices of your channels array. The Twitch API only provides details for currently live streams within a ‘data’ field, meaning you should first access $data['data']. This array contains only the active channels, and any channels that are not streaming will not be included. I encountered a similar issue when I began working with streaming APIs, as they exclusively return information on active streams. Update your loop to iterate through $data['data'] instead of relying on $channelsArray indices. Additionally, implementing error checks for potential API failures or unexpected data formats would be beneficial.

6

Yeah, same thing happened to me. You’re trying to access $data[$index] but the Twitch API doesn’t work that way. Check if $data['data'] exists first, then loop through that array instead of using channel indexes.