Reply To: Query posts by user relationship field

• haydeningham

• September 10, 2021 at 9:15 am

@hube2 okay thanks John, here is my code. Do I just wrap the update_post_meta value in quotes?

/**
   * The relationship between the class and swimmer for confirmed classes.
   *
   * @since    1.0.0
   */  
  public function class_swimmer_relationship($value, $post_id, $field) {

		// set the two fields that you want to create
		// a two way relationship for
		// these values can be the same field key
		// if you are using a single relationship field
		// on a single post type
	
		// the field key of one side of the relationship
		$key_a = 'field_spal_swimmer_classes';
		// the field key of the other side of the relationship
		// as noted above, this can be the same as $key_a
		$key_b = 'field_spal_class_swimmers';
	
		// figure out wich side we're doing and set up variables
		// if the keys are the same above then this won't matter
		// $key_a represents the field for the current posts
		// and $key_b represents the field on related posts
		if ($key_a != $field['key']) {
			// this is side b, swap the value
			$temp = $key_a;
			$key_a = $key_b;
			$key_b = $temp;
		}
	
		// get both fields
		// this gets them by using an acf function
		// that can gets field objects based on field keys
		// we may be getting the same field, but we don't care
		$field_a = acf_get_field($key_a);
		$field_b = acf_get_field($key_b);
	
		// set the field names to check
		// for each post
		$name_a = $field_a['name'];
		$name_b = $field_b['name'];
	
		// get the old value from the current post
		// compare it to the new value to see
		// if anything needs to be updated
		// use get_post_meta() to a avoid conflicts
		$old_values = get_post_meta($post_id, $name_a, true);
		// make sure that the value is an array
		if (!is_array($old_values)) {
			if (empty($old_values)) {
				$old_values = array();
			} else {
				$old_values = array($old_values);
			}
		}
		// set new values to $value
		// we don't want to mess with $value
		$new_values = $value;
		// make sure that the value is an array
		if (!is_array($new_values)) {
			if (empty($new_values)) {
				$new_values = array();
			} else {
				$new_values = array($new_values);
			}
		}
	
		// get differences
		// array_diff returns an array of values from the first
		// array that are not in the second array
		// this gives us lists that need to be added
		// or removed depending on which order we give
		// the arrays in
	
		// this line is commented out, this line should be used when setting
		// up this filter on a new site. getting values and updating values
		// on every relationship will cause a performance issue you should
		// only use the second line "$add = $new_values" when adding this
		// filter to an existing site and then you should switch to the
		// first line as soon as you get everything updated
		// in either case if you have too many existing relationships
		// checking end updated every one of them will more then likely
		// cause your updates to time out.
		//$add = array_diff($new_values, $old_values);
		$add = $new_values;
		$delete = array_diff($old_values, $new_values);
	
		// reorder the arrays to prevent possible invalid index errors
		$add = array_values($add);
		$delete = array_values($delete);
	
		if (!count($add) && !count($delete)) {
			// there are no changes
			// so there's nothing to do
			return $value;
		}
	
		// do deletes first
		// loop through all of the posts that need to have
		// the recipricol relationship removed
		for ($i=0; $i<count($delete); $i++) {
			$related_values = get_post_meta($delete[$i], $name_b, true);
			if (!is_array($related_values)) {
				if (empty($related_values)) {
					$related_values = array();
				} else {
					$related_values = array($related_values);
				}
			}
			// we use array_diff again
			// this will remove the value without needing to loop
			// through the array and find it
			$related_values = array_diff($related_values, array($post_id));
			// insert the new value
			update_post_meta($delete[$i], $name_b, $related_values);
			// insert the acf key reference, just in case
			update_post_meta($delete[$i], '_'.$name_b, $key_b);
		}
	
		// do additions, to add $post_id
		for ($i=0; $i<count($add); $i++) {
			$related_values = get_post_meta($add[$i], $name_b, true);
			if (!is_array($related_values)) {
				if (empty($related_values)) {
					$related_values = array();
				} else {
					$related_values = array($related_values);
				}
			}
			if (!in_array($post_id, $related_values)) {
				// add new relationship if it does not exist
				$related_values[] = $post_id;
			}
			// update value
			update_post_meta($add[$i], $name_b, $related_values);
			// insert the acf key reference, just in case
			update_post_meta($add[$i], '_'.$name_b, $key_b);
		}
	
		return $value;
	
	} // end function acf_reciprocal_relationship
	
	/**
   * The relationship between the class and swimmer for provisional classes.
   *
   * @since    1.0.0
   */  
	function class_swimmer_provisional_relationship($value, $post_id, $field) {

		// set the two fields that you want to create
		// a two way relationship for
		// these values can be the same field key
		// if you are using a single relationship field
		// on a single post type
	
		// the field key of one side of the relationship
		$key_a = 'field_spal_swimmer_provisional_classes';
		// the field key of the other side of the relationship
		// as noted above, this can be the same as $key_a
		$key_b = 'field_spal_class_provisional_swimmers';
	
		// figure out wich side we're doing and set up variables
		// if the keys are the same above then this won't matter
		// $key_a represents the field for the current posts
		// and $key_b represents the field on related posts
		if ($key_a != $field['key']) {
			// this is side b, swap the value
			$temp = $key_a;
			$key_a = $key_b;
			$key_b = $temp;
		}
	
		// get both fields
		// this gets them by using an acf function
		// that can gets field objects based on field keys
		// we may be getting the same field, but we don't care
		$field_a = acf_get_field($key_a);
		$field_b = acf_get_field($key_b);
	
		// set the field names to check
		// for each post
		$name_a = $field_a['name'];
		$name_b = $field_b['name'];
	
		// get the old value from the current post
		// compare it to the new value to see
		// if anything needs to be updated
		// use get_post_meta() to a avoid conflicts
		$old_values = get_post_meta($post_id, $name_a, true);
		// make sure that the value is an array
		if (!is_array($old_values)) {
			if (empty($old_values)) {
				$old_values = array();
			} else {
				$old_values = array($old_values);
			}
		}
		// set new values to $value
		// we don't want to mess with $value
		$new_values = $value;
		// make sure that the value is an array
		if (!is_array($new_values)) {
			if (empty($new_values)) {
				$new_values = array();
			} else {
				$new_values = array($new_values);
			}
		}
	
		// get differences
		// array_diff returns an array of values from the first
		// array that are not in the second array
		// this gives us lists that need to be added
		// or removed depending on which order we give
		// the arrays in
	
		// this line is commented out, this line should be used when setting
		// up this filter on a new site. getting values and updating values
		// on every relationship will cause a performance issue you should
		// only use the second line "$add = $new_values" when adding this
		// filter to an existing site and then you should switch to the
		// first line as soon as you get everything updated
		// in either case if you have too many existing relationships
		// checking end updated every one of them will more then likely
		// cause your updates to time out.
		//$add = array_diff($new_values, $old_values);
		$add = $new_values;
		$delete = array_diff($old_values, $new_values);
	
		// reorder the arrays to prevent possible invalid index errors
		$add = array_values($add);
		$delete = array_values($delete);
	
		if (!count($add) && !count($delete)) {
			// there are no changes
			// so there's nothing to do
			return $value;
		}
	
		// do deletes first
		// loop through all of the posts that need to have
		// the recipricol relationship removed
		for ($i=0; $i<count($delete); $i++) {
			$related_values = get_post_meta($delete[$i], $name_b, true);
			if (!is_array($related_values)) {
				if (empty($related_values)) {
					$related_values = array();
				} else {
					$related_values = array($related_values);
				}
			}
			// we use array_diff again
			// this will remove the value without needing to loop
			// through the array and find it
			$related_values = array_diff($related_values, array($post_id));
			// insert the new value
			update_post_meta($delete[$i], $name_b, $related_values);
			// insert the acf key reference, just in case
			update_post_meta($delete[$i], '_'.$name_b, $key_b);
		}
	
		// do additions, to add $post_id
		for ($i=0; $i<count($add); $i++) {
			$related_values = get_post_meta($add[$i], $name_b, true);
			if (!is_array($related_values)) {
				if (empty($related_values)) {
					$related_values = array();
				} else {
					$related_values = array($related_values);
				}
			}
			if (!in_array($post_id, $related_values)) {
				// add new relationship if it does not exist
				$related_values[] = $post_id;
			}
			// update value
			update_post_meta($add[$i], $name_b, $related_values);
			// insert the acf key reference, just in case
			update_post_meta($add[$i], '_'.$name_b, $key_b);
		}
	
		return $value;
	
	} // end function acf_reciprocal_relationship