Bulk Importing tags and assigning to wordpress posts from csv file

importing-bulk-tags-wp-from-csv.php

<?php
class CsvImporter
{
	private $fp;
	private $parse_header;
	private $header;
	private $delimiter;
	private $length;
	//--------------------------------------------------------------------
	function __construct($file_name, $parse_header = false, $delimiter = "\t", $length = 8000)
	{
		$this->fp = fopen($file_name, "r");
		$this->parse_header = $parse_header;
		$this->delimiter = $delimiter;
		$this->length = $length;
		// $this->lines = $lines;

		if ($this->parse_header) {
			$this->header = fgetcsv($this->fp, $this->length, $this->delimiter);
		}
	}
	//--------------------------------------------------------------------
	function __destruct()
	{
		if ($this->fp) {
			fclose($this->fp);
		}
	}
	//--------------------------------------------------------------------
	function get($max_lines = 0)
	{
		//if $max_lines is set to 0, then get all the data

		$data = array();

		if ($max_lines > 0)
			$line_count = 0;
		else
			$line_count = -1; // so loop limit is ignored

		while ($line_count < $max_lines && ($row = fgetcsv($this->fp, $this->length, $this->delimiter)) !== FALSE) {
			if ($this->parse_header) {
				foreach ($this->header as $i => $heading_i) {
					$row_new[$heading_i] = $row[$i];
				}
				$data[] = $row_new;
			} else {
				$data[] = $row;
			}

			if ($max_lines > 0)
				$line_count++;
		}
		return $data;
	}
	//--------------------------------------------------------------------

}

?>

<?php

echo 'Adding tags \n Check for errors in the output after import.';

$importer = new CsvImporter(get_template_directory() . '/tags.csv', true, ",");
$data = $importer->get();
// $test = array_shift($data); 
$results = array();

foreach ($data as $row) {
	$postID = $row['id'];
	if ($row['tags']) {
		$tags = explode('|', $row['tags']);
		$termsToAttach = array();

		foreach ($tags as $tag) {
			if ($tag) {
				$existingTag = get_term_by('name', $tag, 'post_tag');
				if (!$existingTag) {
					$newTag = wp_insert_term(
						$tag,
						'post_tag',
						array(
							'description' => '',
							'slug' => createSlug($tag),
						)
					);
					$existingTag = get_term_by('id', $newTag['term_id'], 'post_tag');
				}
				$tagID = (int) $existingTag->term_id;
				array_push($termsToAttach, $tagID); 
			}
		}

		$result = wp_set_post_terms($postID, $termsToAttach, 'post_tag', true);
		array_push($results, $result);
	}
}

var_export($result);