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PHP

Mayur Pande
PLUS
Mayur Pande
Courses Plus Student 11,711 Points
Posted by Mayur Pande
Mayur Pande
Courses Plus Student 11,711 Points

Impossible to access attribute ('booked') on null

I am using twig to display whether or not someone has been booked for a lesson.

I have managed to get it working however I am a bit confused. At first I was getting the error in the title

Impossible to access attribute ('booked') on null

However my function get_student_driver_booked below, is returning correct array

    public function get_student_driver_booked($email){

        $email = mysqli_real_escape_string($this->link,$email);

        $result = mysqli_query($this->link,"select *,(select '$email' in 
                       (select studentdriverdetails.studentemail
                       from studentdriverdetails
                       inner join driver
                       on studentdriverdetails.driveremail = studentdriverdetails.driveremail
                       where studentdriverdetails.driveremail = driver.driveremail 
                       and studentdriverdetails.starttime = driver.starttime)) as booked from studentdriverdetails   
                       where studentdriverdetails.studentemail='$email' and studentdriverdetails.starttime >= NOW()");

        while($row = mysqli_fetch_assoc($result)){
            $booked = $row;
        }
        return $booked;

    }

Then passing this function to my controller like so;

$app->get('/group-tuition', function() use($app) {
    $groups = $app['tutor']->get_group_tuition($app['auth']->get_user()['email']);
    $driver = $app['tutor']->get_driver_details();
    $counter = $app['tutor']->get_student_driver_count($driver['driveremail'],$groups[0]['tutoremail'],$groups[0]['starttime']);
    $test = $app['tutor']->get_student_driver_booked($app['auth']->get_user()['email']);

    return $app['twig']->render('group-tuition.twig', array(
            'active_page' => 'group-tuition', 
            'is_user_logged_in' => $app['auth']->is_user_logged_in(),
            'groups' => $groups, 'user' => $app['auth']->get_user(), 
            'drivers' => $driver, 
            'counter' => $counter,
            'test' => $test
    ));
});

After running var_dump tests on $test it was apparent my function returned the correct results.

However when using this in my twig file. I could not access the "booked" attribute (key).

I am not sure exactly why this is, I mean it works so not sure if I should have the mind frame "if it ain't broke don't fix it" But I am curious to know why it is not letting me access that key.

Here is what my twig file looks like;

<tbody>
                    {% for group in groups %}
                    <tr>
                        <td>{{ group.datetime }}</td>
                        <td>{{ group.location }}</td>
                        <td><a class="group-tutors" href="/tutor/{{ group.username }}">{{ group.name }}</a></td>
                        <td>{{ group.class }}</td>
                        <td>{{ group.level }}</td>
                        <td>{{ group.topic }}</td>
                        <td>{{ group.available }}/{{ group.capacity }}</td>
                        <td>

                                <a class="group-tutors" href="/login">Login</a>
                                {% elseif group.booked and not test and counter.available > 0  %}
                                Booked! If you would like a ride to the lesson there are {{ counter.available }} spaces left 
                                <form action="/charge1" method="post">
                                    <script
                                        src="https://checkout.stripe.com/checkout.js" class="stripe-button"
                                        data-key="pk_test"
                                        data-image="images/footer-icon.png"
                                        data-name="SOUTH LONDON TUTORS"
                                        data-description="Lift"
                                        data-amount="500"
                                        data-currency="GBP"
                                        data-locale="auto">
                                    </script>
                                    <input type="hidden" name="tutoremail" value="{{ group.tutoremail }}" />
                                    <input type="hidden" name="starttime" value="{{ group.starttime }}" />
                                    <input type="hidden" name="endtime" value="{{ group.endtime }}" />
                                    <input type="hidden" name="location" value="{{ group.location }}" />
                                    <input type="hidden" name="class" value="{{ group.class }}" />
                                    <input type="hidden" name="driveremail" value="{{ drivers.driveremail }}" />
                                </form>
                            {% elseif group.booked and test  %}
                                Booked for both lesson and ride to lesson
                            {% elseif group.booked %}
                                Booked for lesson
                            {% elseif group.available > 0 %}
                                <form action="/charge" method="post">
                                    <script
                                        src="https://checkout.stripe.com/checkout.js" class="stripe-button"
                                        data-key="pk_test"
                                        data-image="images/footer-icon.png"
                                        data-name="SOUTH LONDON TUTORS"
                                        data-description="{{ group.topic }}"
                                        data-amount="2000"
                                        data-currency="GBP"
                                        data-locale="auto">
                                    </script>
                                    <input type="hidden" name="tutoremail" value="{{ group.tutoremail }}"/>
                                    <input type="hidden" name="starttime" value="{{ group.starttime }}"/>
                                    <input type="hidden" name="description" value="{{ group.topic }}"/>
                                </form>

                            {% else %}
                                Full
                            {% endif %}
                        </td>
                        {% if is_user_logged_in and (user.type == "admin" or user.type == "tutor" and user.email == group.tutoremail) %}
                            <td><a class="group-tutor" href="/group-tuition/{{ group.tutoremail }}/{{ group.starttime }}">View Students</a></td>
                        {% endif %}
                    </tr>
                    {% endfor %}
                </tbody>