ExpressionEngine PHP Export into JSON

export.php

<?php

$channel = $_GET['id'];
$content = array();

$fields_query = $this->EE->db->query("SELECT * FROM exp_channel_fields LEFT JOIN exp_channels ON exp_channel_fields.group_id = exp_channels.field_group WHERE exp_channels.channel_id = '$channel'");

$entries_query = $this->EE->db->query("SELECT * FROM exp_channel_data cd INNER JOIN exp_channel_titles ct ON cd.entry_id = ct.entry_id WHERE cd.channel_id = '$channel'");

$fields = $fields_query->result_array();

foreach ($entries_query->result_array() as $id => $row) {
    $content[$id] = array();
    $content[$id]['title'] = $row['title'];
    $content[$id]['url_title'] = $row['url_title'];
    $content[$id]['status'] = $row['status'];
    $content[$id]['enabled'] = ($row['status'] == 'closed') ? 0 : 1;
    $content[$id]['entry_date'] = ($row['entry_date']) ? date('Y-m-d H:i:s', $row['entry_date']) : '';
    $content[$id]['expiration_date'] = ($row['expiration_date']) ? date('Y-m-d H:i:s', $row['expiration_date']) : '';
    $content[$id]['author_id'] = $row['author_id'];
    
    // Handle category
    $categories = $this->EE->db->query("SELECT * FROM exp_category_posts c JOIN exp_categories cp ON c.cat_id = cp.cat_id WHERE entry_id = ".$row['entry_id'])->result_array();

    if ($categories) {
        foreach ($categories as $category) {
            $content[$id]['category_' . $category['group_id']][] = $category['cat_name'];
        }
    }
    
    foreach ($fields as $field) {
        // Support for P&T Matrix field
        if ($field['field_type'] == 'matrix') {
            $query = $this->EE->db->query("SELECT * FROM exp_matrix_cols WHERE field_id=".$field['field_id']);

            foreach ($query->result_array() as $matrix_col) {
                $query = $this->EE->db->query("SELECT * FROM exp_matrix_data WHERE field_id=".$field['field_id']." AND entry_id=".$row['entry_id']." ORDER BY row_order");

                foreach ($query->result_array() as $key => $matrix_row) {
                    // Support for File field
                    if ($matrix_col['col_type'] == 'file') {
                        $this->EE->load->library('file_field');
                        $fileInfo = $this->EE->file_field->parse_field($matrix_row['col_id_'.$matrix_col['col_id']]);
                        
                        $content[$id][$field['field_name']][$key][$matrix_col['col_name']] = $fileInfo['url'];
                    } else {
                        // Any other field
                    	$content[$id][$field['field_name']][$key][$matrix_col['col_name']] = $matrix_row['col_id_'.$matrix_col['col_id']];
                    }
                }
            }
        // Support for P&T Playa field
        } elseif ($field['field_type'] == 'playa') {
            // Change from "[93] [my-category] My Category" = "My Category"
            $value = preg_replace("/\[[^]]+\]/", '', $row['field_id_' . $field['field_id']]);
            
            $content[$id][$field['field_name']] = trim($value);
            
        // Support for File field
        } elseif ($field['field_type'] == 'file') {
            $this->EE->load->library('file_field');
            $fileInfo = $this->EE->file_field->parse_field($row['field_id_' . $field['field_id']]);
            
            $content[$id][$field['field_name']] = $fileInfo['url'];
            
        // Support for P&T Assets field
        } elseif ($field['field_type'] == 'assets') {
            $value = $row['field_id_' . $field['field_id']];
            
            $content[$id][$field['field_name']] = $value;
            
        } else {
            // Any other field
            $content[$id][$field['field_name']] = $row['field_id_' . $field['field_id']];
        }
    }
}
    
echo json_encode($content);

?>

Hey everyone, not sure how many people are still doing this but I thought I might add my edits for whoever it might help. I found that files/and assets, particularly one's using aws' S3 buckets, didn't work well. I also had issues with categories not working. There is also a seperate template for Members/Users which is the second snippet

<?php

$channel = $_GET['id'];
$content = array();

$fields_query = $this->EE->db->query("SELECT * FROM exp_channel_fields LEFT JOIN exp_channels ON exp_channel_fields.group_id = exp_channels.field_group WHERE exp_channels.channel_id = '$channel'");

$entries_query = $this->EE->db->query("SELECT * FROM exp_channel_data cd INNER JOIN exp_channel_titles ct ON cd.entry_id = ct.entry_id WHERE cd.channel_id = '$channel'");

$fields = $fields_query->result_array();

foreach ($entries_query->result_array() as $id => $row) {
    $content[$id] = array();
    $content[$id]['title'] = $row['title'];
    $content[$id]['url_title'] = $row['url_title'];
    $content[$id]['status'] = $row['status'];
    $content[$id]['enabled'] = ($row['status'] == 'closed') ? 0 : 1;
    $content[$id]['entry_date'] = ($row['entry_date']) ? date('Y-m-d H:i:s', $row['entry_date']) : '';
    $content[$id]['expiration_date'] = ($row['expiration_date']) ? date('Y-m-d H:i:s', $row['expiration_date']) : '';
    $content[$id]['author_id'] = $row['author_id'];
    
    // Handle category
    $categories = $this->EE->db->query("SELECT * FROM exp_category_posts c JOIN exp_categories cp ON c.cat_id = cp.cat_id WHERE entry_id = ".$row['entry_id'])->result_array();

    if ($categories) {
        foreach ($categories as $category) {
            $content[$id]['category_' . $category['group_id']][] = $category['cat_name'];
        }
    }
    
    foreach ($fields as $field) {
        // Support for P&T Matrix field
        if ($field['field_type'] == 'matrix') {
            $query = $this->EE->db->query("SELECT * FROM exp_matrix_cols WHERE field_id=".$field['field_id']);

            foreach ($query->result_array() as $matrix_col) {
                $query = $this->EE->db->query("SELECT * FROM exp_matrix_data WHERE field_id=".$field['field_id']." AND entry_id=".$row['entry_id']." ORDER BY row_order");

                foreach ($query->result_array() as $key => $matrix_row) {
                    // Support for File field
                    if ($matrix_col['col_type'] == 'file') {
                        $this->EE->load->library('file_field');
                        $fileInfo = $this->EE->file_field->parse_field($matrix_row['col_id_'.$matrix_col['col_id']]);
                        
                        $content[$id][$field['field_name']][$key][$matrix_col['col_name']] = $fileInfo['url'];
                    } else {
                        // Any other field
                    	$content[$id][$field['field_name']][$key][$matrix_col['col_name']] = $matrix_row['col_id_'.$matrix_col['col_id']];
                    }
                }
            }
        // Support for P&T Playa field
        } elseif ($field['field_type'] == 'playa') {
            $productList = array();
            $lines = explode("\n", $row['field_id_' . $field['field_id']]);
            if ($field['field_label'] == 'Products'){            
                foreach($lines as $line){
                    $matches = array();
                    preg_match_all("/(?<=\[)([^\[\]]*)(?=\])/", $line, $matches);
                    $product = $matches[0]; //= ~["29","10-resources-to-teach-stem-in-afterschool"]
                    if(count($product) == 0){ break; }
                    array_push($productList, $product[1]);
                }

                // var_dump($matches);
                $content[$id][$field['field_name']] = $productList;
            }
            else {
                // Change from "[93] [my-category] My Category" = "My Category"   
                foreach($lines as $line){    
                    array_push($productList, preg_replace("/\[[^]]+\]\s*/", '', $line));
                }
                // $content[$id][$field['field_name']] = trim($value);
                $content[$id][$field['field_name']] = $productList;
            }
            
        // Support for File field   
        } elseif ($field['field_type'] == 'file') {
            $url;
            if($field['field_name'] == 'product_thumbnail' || $field['field_name'] == 'product_detail_image') {
                $url = preg_replace('/{.*}/', '', $row['field_id_' . $field['field_id']]);
            }
            else {
                $this->EE->load->library('file_field');
                $fileInfo = $this->EE->file_field->parse_field($row['field_id_' . $field['field_id']]);
                $url = $fileInfo['url'];
            }
            $content[$id][$field['field_name']] = $url;
        //Channel Images
        } elseif ($field['field_type'] == 'channel_images') {
            $imageQuery = $this->EE->db->query("SELECT * FROM exp_channel_images WHERE field_id=".$field['field_id']." and entry_id=".$row['entry_id']);
            $images = array();

            foreach ($imageQuery->result_array() as $iid => $image) {
                $images[$iid] = array();

                $images[$iid]['Title'] = $image['title'];
                $images[$iid]['URL'] = '/' . $image['filename'];
                $images[$iid]['Caption'] = $image['description'];
            }
            $content[$id][$field['field_name']] = $images;

        // Support for P&T Assets field
        } elseif ($field['field_type'] == 'assets') {
            $value = $row['field_id_' . $field['field_id']];
            $content[$id][$field['field_name']] =$value;
            
        } else {
            // Any other field
            $content[$id][$field['field_name']] = $row['field_id_' . $field['field_id']];
        }
    }
}
    
echo json_encode($content);

?>

User Export - id is the group id

<?php

$group = $_GET['id'];
$content = array();

$fields_query = $this->EE->db->query("SELECT * FROM exp_member_fields;");

$entries_query = $this->EE->db->query("
    SELECT m.group_id, m.username, m.screen_name, m.email, md.* FROM exp_member_data md
    INNER JOIN exp_members m ON md.member_id = m.member_id 
    WHERE m.group_id = '$group';");

$fields = $fields_query->result_array();

foreach ($entries_query->result_array() as $id => $row) {
    $content[$id] = array();
    $content[$id]['username'] = $row['username'];
    $content[$id]['screen_name'] = $row['screen_name'];
    $content[$id]['email'] = $row['email'];
    
    foreach ($fields as $field) {
        $content[$id][$field['m_field_name']] = $row['m_field_id_' . $field['m_field_id']];
    }
}
    
echo json_encode($content);

?>