How can I restrict polls so each logged in user votes only once?

Hi @loehoafaq

I hope you’re well today!

Currently it’s not possible to restrict this way by user. We do have this feature already planned for future so it will be added with one of future releases but I don’t have version and ETA yet.

It may possibly be doable with a bit of additional custom code but I need to consult our developers about it so I’d appreciate some patience on it. I have already asked them to check and we’ll update you here once we got response.

Best regards,
Adam

Thanks, Adam. Look forward to your reply. I’ve set up an Astra child theme in which I’ve already got some custom code, so adding more would be a feasible solution for me.

Hi @loehoafaq,

Could you please try this code and see whether it helps?

<?php

add_filter( 'forminator_poll_handle_form_user_can_vote', 'wmudev_check_user_submission_poll', 10, 2 );
function wmudev_check_user_submission_poll( $user_can_vote, $module_id ) {
    if ( $module_id != 230 ) { //Please change the poll ID
        return $user_can_vote;
    }

    if ( !is_user_logged_in() ) {
        return $user_can_vote;
    }

    $user_id = get_current_user_id();

    $users_with_vote = get_option( $module_id.'_poll_users', array() );
    if ( ! empty( $users_with_vote ) ) {
        if ( in_array( $user_id, $users_with_vote ) ) {
            $user_can_vote = false;
            throw new Exception( esc_html__( 'You have already submitted a vote to this poll', 'forminator' ) );
        }
    }

    return $user_can_vote;
}

add_action( 'forminator_poll_after_handle_submit', 'wpmudev_record_user_poll_submission', 10, 2 );
add_action( 'forminator_poll_after_save_entry', 'wpmudev_record_user_poll_submission', 10, 2 );
function wpmudev_record_user_poll_submission( $module_id, $response ) {
    if ( $module_id != 230 ) { //Please change the poll ID
        return;
    }

    if ( is_user_logged_in() ) {
        $user_id = get_current_user_id();
        $option = get_option( $module_id.'_poll_users', array() );
        array_push( $option, $user_id );
        $updated_option = array_unique( $option );
        update_option( $module_id.'_poll_users', $updated_option );
    }
}

In the above code, you’ll have to update the number 230 to your Form ID. Suppose your form ID is 123, then the code will change as:

if ( $module_id != 123 )

You can apply the code as a mu-plugins. Please check this link on how to implement the above code as a mu-plugins:
https://wpmudev.com/docs/using-wordpress/installing-wordpress-plugins/#installing-mu-plugins

Best Regards,

Nithin

I have a couple of questions

1. Am I correct in thinking module_id is passed in as the id of the current poll by forminator, and if I want every poll to be treated this way I can just remove the check for a specific value [if ( $module_id != 230 )]?
2. Since I only want logged in users who haven’t previously voted to be able to vote, wouldn’t I want to modify the code as follows to exclude those who are not logged in?
   • if (!is_user_logged_in()) { return false;}
3. Although I’m a programmer, I’m a rank amateur when it comes to WordPress hooks. Will these functions be automatically called for each poll or must I add something to cause that to happen?
4. Other than observing the behavior of my polls when I test this, is there any log file I should examine for evidence of what’s happening?

Thanks very much for your reply and the effort you put into this. I’ll try it tomorrow and let you know how it goes.

Hi @loehoafaq

Am I correct in thinking module_id is passed in as the id of the current poll by forminator, and if I want every poll to be treated this way I can just remove the check for a specific value [if ( $module_id != 230 )]?

Yes, if you don’t want to restrict the IDs you can remove that part.

Since I only want logged in users who haven’t previously voted to be able to vote, wouldn’t I want to modify the code as follows to exclude those who are not logged in?

If we are on the same page, any logged out user would be able to vote but logged in could vote only once? If so you need to replace the:

if ( !is_user_logged_in() ) {
        return $user_can_vote;
    }

to

if ( is_user_logged_in() ) {
        return $user_can_vote;
    }

But in case it is a different situation please let us know, the code now will check if user is logged out won’t allow to vote, for logged in users it allow only once.

Although I’m a programmer, I’m a rank amateur when it comes to WordPress hooks. Will these functions be automatically called for each poll or must I add something to cause that to happen?

It will be automatically for any Poll this is why we had to implement the ID validation.

Other than observing the behavior of my polls when I test this, is there any log file I should examine for evidence of what’s happening?

The best test would be using a Staging site and then trying out the code across different polls, it won’t create any log other than register the new vote or prevent duplicated votes.

Let us know if you have any additional questions.
Best Regards
Patrick Freitas

Test Methodology

1. I created a new poll (forminator_poll id=”260″), verified that it works properly, then duplicated it (forminator_poll id=”266″).
2. I followed the provided instructions to add the following code to a mu-plugins php file with the correct permissions.

<?php

add_filter( 'forminator_poll_handle_form_user_can_vote', 'wmudev_check_user_submission_poll', 10, 2 );
function wmudev_check_user_submission_poll( $user_can_vote, $module_id ) {

    if ( $module_id != 266 ) {        // Only apply filter to copy of test poll
        return $user_can_vote;
    }

//    if ( !is_user_logged_in() ) {
//        return $user_can_vote;
//    }

    if ( !is_user_logged_in() ) {     // only logged-in users can vote
        $user_can_vote = false;
        throw new Exception( esc_html__( 'You must be logged in to vote in this poll', 'forminator' ) );
        return $user_can_vote;
    }

    $user_id = get_current_user_id(); // get logged-in user's user_id

    $users_with_vote = get_option( $module_id.'_poll_users', array() );   // get list of those who have previously voted in this poll
    if ( ! empty( $users_with_vote ) ) {
        if ( in_array( $user_id, $users_with_vote ) ) {                   // if logged-in user is in that list...
            $user_can_vote = false;                                       //  they can't vote again
            throw new Exception( esc_html__( 'You have already submitted a vote to this poll', 'forminator' ) );
        }
    }

    return $user_can_vote;
}

add_action( 'forminator_poll_after_handle_submit', 'wpmudev_record_user_poll_submission', 10, 2 );
add_action( 'forminator_poll_after_save_entry', 'wpmudev_record_user_poll_submission', 10, 2 );
function wpmudev_record_user_poll_submission( $module_id, $response ) {
//    if ( $module_id != 230 ) { //Please change the poll ID
//        return;
//    }

    if ( is_user_logged_in() ) {
        $user_id = get_current_user_id();                                 // get user_id
        $option = get_option( $module_id.'_poll_users', array() );        // get array of those who have already voted in this poll
        array_push( $option, $user_id );                                  // add user_id to the array
        $updated_option = array_unique( $option );                        // update the array
        update_option( $module_id.'_poll_users', $updated_option );
    }
}

• I then embedded the short codes for the polls in this page:

https://liveoakestateshoa.com/test-poll-page/

Neither is rendered correctly.

If I move my php file out of the mu-plugins directory, both render correctly.

I’ve left the php file in the mu-plugins directory so you can see what happens.

What additional information can I provide to help debug this?

Thanks!

Hi @loehoafaq

Thanks for response!

I checked the code and there seems to be two issues here:

1. Apparently there’s small “inconsistency” happening due to the hook priority set so you would need to do a small change and in this line

add_filter( 'forminator_poll_handle_form_user_can_vote', 'wmudev_check_user_submission_poll', 10, 2 );

change number 10 to, for example, 99.

With it the code will work as designed (at least it does in my tests).

2. But the second issue may be, it seems, a misunderstanding on our end. The way it currently works is that (after above change) it does allow voting to logged-in users only but it does not hide the poll or give error message right away; it will only show it after you attempt to vote:

– so poll shows up
– you vote
– if you are logged-in, your vote is registered or you get “you already voted” error (if you did vote already)
– if you are not logged-in, after poll submission you get “you must be logged-in” message

But if I’m getting it correctly, you would want that message to be showing up right away, before user is even able to try to submit the vote, right?

I think this may require a bit different approach so I’ve asked our developers if they could adjust the code to achieve that and I’m awaiting their response.

We’ll update you here soon with more information.

Best regards,
Adam

I can prevent non-registered users from voting by restricting rendering with [um_show_content =’ list of user roles’] as I’m doing on other pages. I didn’t because then you wouldn’t have been able to see it.

Where in the database can I find the data showing which users have voted in any given poll? Perhaps that would be enlightening?

Hi @loehoafaq

Thanks for response!

I actually got reply from our developers too already and to make it limited for logged-in users you would need to add following code additionally to the one that you are already using:

add_filter( 'forminator_render_button_markup', 'wpmudev_change_poll_markup', 10, 2 );
function wpmudev_change_poll_markup( $html, $button ) {

    if ( ! is_user_logged_in() ) {
        $html = '<br/><p>You must be logged in to vote in this poll.</p>';
    }

    return $html;
}

Simply add it at the end of existing code and it hsould do the trick.

As for “which users voted”, with the code that you are using already the info about users (user ID) would be stored in the standard _options table of the site, under option name of

xx_poll_users

where xx is the number – an ID of the poll.

Kind regards,
Adam

That’s great. When not logged in, the user sees a message saying “You must be logged in to vote in this poll.” instead of the “Vote” button.

Logged in users see the “Vote” button. If a user who hasn’t voted before clicks on the “Vote” button their vote is counted and the current results are displayed (which is how I configured this poll). If they have voted before they see instead “You have already submitted a vote to this poll” at the top of the poll.

This achieves my goal of allowing only logged in users to vote, and then only once. It would be even better if the “You have already submitted a vote to this poll” could be displayed without the user having to make selections and submit the poll. Our website is for a homeowners association, and each household gets one vote on each issue. As a result, user IDs will be shared by spouses. Some of our polls will be quite long; if we told users they’d already vote before they start filling out the poll it could save them both time and annoyance when their spouse has already voted for their household.

Might that be possible?

I found the xx_poll_users records in the wp_options table in the WordPress db. If I wanted to start a poll over, could I do this by deleting the corresponding record? Is there any other cleanup needed? Or can this be done from the WP admin interface?

Are detailed results available, preferably in an anonymous but per-vote form, so we can export to a spreadsheet and do custom analysis?

Is the schema for poll data available?

Hi @loehoafaq

Thanks for response and I’m glad it worked for you.

As for the “You have submitted a vote” information

It actually should be displayed right away, when the poll displays and it does that in my tests. But please try one thing:

Previously I suggested changing priority in this part of the code

add_filter( 'forminator_poll_handle_form_user_can_vote', 'wmudev_check_user_submission_poll', 10, 2 );

to something like 99 but with the new code added it may no longer be necessary so try lowering it a bit again – test setting it back to 10 or even 9 and see if that sorts the issue.

As for the xx_poll_users records

You can delete them and they’ll be recreated. They don’t cary any additional information as they are create by that custom code and the only purpose is to identify if a given logged-in user already voted or not. Adding any additional information to that would require more complex code and, I’m afraid, would be out of scope of this support.

However, if you have “Data storage” option for you poll set to have “Store Submission in Database” enabled (it’s in “Settings” section of each poll), poll voting would be saved in DB by plugin and you would see those submissions on “Forminator -> Submissions” page after you select relevant poll from the drop-down list on top.

Once you got that, you can use “Export” option to export voting to CSV file which you can later import e.g. to Google Sheets or any similar software for further analysis.

It doesn’t contain much information but it does contain dates of when the answers were given and answers themselves.

Best regards,
Adam

Hello @loehoafaq ,

We haven’t heard from you for over a week now, so it looks like you don’t have more questions for us.

Feel free to re-open this topic if needed.

Kind regards
Kasia