Form validation codeigniter not work and how to upload picture?

Question

i'm new of codeigniter, i have some problem when using form validation to insert data to database with upload some picture. First when i click submit button without any input , the error info from form validation not showing view. Second when i give some input then i click submit button it just refresh the page. Third i learn to upload some image to database, but i'm not sure it's correct. Please help me, i appreciate every answer and advice.

My view (transfer.php):

<section class="columns is-centered my-5">
<div class="container column is-half">
    <form action="<?= base_url() ?>bukti_add" method="POST">
        <p class="has-text-warning-light">
            <?=
                validation_errors();
            ?>
        </p>
        <input type="hidden" name="bukti_id" value="">
        <input class="input" type="text" name="bukti_nama_pengirim" value="" placeholder="Masukan Nama Pengirim">
        <select class="select input" name="bukti_bank_pengirim" id="">
            <option value="">---Pilih Bank Pengirim---</option>
            <option value="">Mandiri</option>
            <option value="">BCA</option>
            <option value="">BNI</option>
            <option value="">BRI</option>
            <option value="">CIMB</option>
            <option value="">Bank Jateng</option>
        </select>
        <input class="input" type="text" name="bukti_jumlah_transfer" value="" placeholder="Masukan Jumlah Transfer">
        <div class="file has-name is-danger">
            <label class="file-label"">
                <input class=" file-input" type="file" name="bukti_img">
                <span class="file-cta">
                    <span class=" file-icon">
                        <i class="fas fa-upload"></i>
                    </span>
                    <span class="file-label">
                        Choose a file…
                    </span>
                </span>
                <span class="file-name" style="background-color: white;">
                    Pilih File Foto Bukti Transfer
                </span>
            </label>
        </div>
        <section>
            <button class="button is-danger" name="">
                Lanjut
            </button>
        </section>
    </form>
</div>

My model(M_checkout):

private function _uploadImage()
{
    $config['upload_path']          = './upload/bukti/';
    $config['allowed_types']        = 'gif|jpg|png';
    $config['file_name']            = $this->get_payment_by_id;
    $config['overwrite']            = true;
    $config['max_size']             = 1024; // 1MB
    // $config['max_width']            = 1024;
    // $config['max_height']           = 768;

    $this->load->library('upload', $config);

    if ($this->upload->do_upload('bukti_img')) {
        return $this->upload->data("file_name");
    }

    return "default.jpg";
}
public function bukti_to_db()
{
    $data = array();
    $data['bukti_nama_pengirim'] = $this->input->post('bukti_nama_pengirim');
    $data['bukti_bank_pengirim'] = $this->input->post('bukti_bank_pengirim');
    $data['bukti_jumlah_transfer'] = $this->input->post('bukti_jumlah_transfer');
    $data['bukti_img'] = $this->_uploadImage();
    $this->db->insert('bukti', $data);
    $bukti_id_save = $this->db->insert_id();
    $sdata = array();
    $sdata['bukti_id'] = $bukti_id_save;

    $this->session->set_userdata($sdata);
}

My controller :

public function bukti_add()
{
    $this->form_validation->set_rules('bukti_nama_pengirim', 'Nama', 'trim|required');
    $this->form_validation->set_rules('bukti_bank_pengirim', 'Bank', 'trim|required');
    $this->form_validation->set_rules('bukti_jumlah_transfer', 'Jumlah Transfer', 'trim|required');
    $this->form_validation->set_rules('bukti_img', 'Bukti Transfer', 'trim|required');

    if ($this->form_validation->run()) {
        $this->M_checkout->bukti_to_db();

        redirect('thank', 'refresh');
    } else {

        redirect('transfer', 'refresh');
    }
}

My database : database

Answer 1

You should print errors while on development. It usualy tells you what's wrong. Ex:

if ($this->upload->do_upload('bukti_img')) {
   return $this->upload->data("file_name");
} else {
   print_r($this->upload->display_errors());
   exit;
}

if ($this->form_validation->run()) {
   $this->M_checkout->bukti_to_db();
   redirect('thank', 'refresh');
} else {
   print_r(validation_errors());
   exit;
}

Though i'm pretty sure you can't validate <input class=" file-input" type="file" name="bukti_img"> with form_validation like that. Since you are validating $_POST while your file is inside the $_FILES variable. Do the file validation on the file upload function.