# ProjectHuddle Data Structures

ProjectHuddle makes use of Custom Post Types and Custom Fields to store it's data, which should make it more familiar to developers familiar with ProjectHuddle.

# Post relationships

ProjectHuddle makes use of post relationships through a parent_id custom field. Much like WordPress uses a "parent" item to identify post relationships, the parent_id identifies the specific conversation thread, project item or project parent.

Here's how these post type relationships are structured:

Project (Mockup or Website Projects)
   └─ Items (Mockup Images or Website Pages)
      └─ Threads (Conversation Threads)
         └─ Comments (Comments or Resolve Actions)

# Getting Parent Posts

ProjectHuddle makes use of the ph_get_parents_ids function to get all the parent ids from a specific post. Here's an example of how you can get the mockup image and mockup project from a conversation thread:

// get parents from a thread post object
$parents = ph_get_parents_ids( $thread->ID );

// get the project id
$project_id = $parents['project'];

// get the image id
$image_id = $parents['item'];

ph_get_parents_ids

# Getting Child Posts

ProjectHuddle makes use of the custom functions to get child posts. We recommend you use these functions to maintain compatibility in case of a change in data structure. The ph_query_project_subcollection function will let you get a child collection from a specific post. Here's an example of how you can get the mockup images collection from a mockup project:

// get parents from a thread post object
$images = ph_query_project_subcollection(array(
    'id' => $mockup_id
));

// do a standard WordPress loop
if ( $images->have_posts() ) {
    while( $images->have_posts() ) : the_post();
        the_title();
    endwhile;
    wp_reset_postdata();
}

ph_query_project_subcollection

# Built-In Functions

ProjectHuddle has many built-in functions to get these relationships. Be sure to check out the relationship functions section for more information on getting post relationships.

Relationship Functions