Issues with PHP Slim framework responding to AngularJS $resource calls

Backend
1

I’m struggling to get my AngularJS frontend to properly communicate with my PHP Slim backend. I keep getting HTTP 200 responses but the content is empty or garbled (119 empty characters).

My AngularJS controller attempts:

First approach using direct $resource:

app.controller('DeviceController', function($scope, $modal, $resource) {
    var deviceId = 1;
    var DeviceResource = $resource('http://example.com/api/phones/' + deviceId);
    $scope.deviceData = DeviceResource.get();
});

Second approach with a service:

app.controller('DeviceController', function($scope, $modal, PhoneService) {
    $scope.deviceData = PhoneService.get({id: 1});
});

app.service('PhoneService', function($resource) {
    return $resource('api/phones/:id', {}, {
        modify: {method: 'PUT'}
    });
});

My PHP Slim backend:

require 'Slim/Slim.php';

$application = new Slim();

$application->get('/', 'getTrendingDevices');
$application->get('/new_phones', 'getLatestPhones');
$application->get('/phones', 'getAllPhones');
$application->get('/new_phones/:id', 'getDeviceDetails');
$application->get('/phones/:id', 'getDeviceDetails');

$application->run();

function getDeviceDetails($deviceId) {
    $query = "SELECT * FROM devices";
    try {
        $database = getDatabaseConnection();
        $statement = $database->query($query);
        $results = $statement->fetchAll(PDO::FETCH_OBJ);
        $database = null;
        echo json_encode($results);
    } catch(PDOException $error) {
        echo '{"error":{"message":' . $error->getMessage() . '}}';
    }
}

The database connection works fine when I test it directly through phpMyAdmin. My table has one row with 21 columns so there should be data returned. Even when I try to return a simple test string, it comes back as corrupted data.

What could be causing this issue with the data transmission between AngularJS and Slim?

2

you should set the content type in slim like this: $application->response->headers->set('Content-Type', 'application/json'); do check for any extra white spaces or BOM chars in your php files too, that can mess with the output.

3

I’ve hit this same corruption issue with Slim before. Usually it’s output buffering or character encoding problems. Your PHP function isn’t actually using the $deviceId parameter in the SQL query - you’re returning all devices no matter what ID gets requested. But here’s the bigger issue: check for any whitespace or output before your JSON response. Add ob_clean() before echoing your JSON and make sure your PHP files don’t have trailing spaces or newlines after the ?> tag. Also verify your database connection returns UTF-8 data by setting the charset in your PDO connection string.