• PHP 5 >= 5.3.0
• WordPress
• Instagram Client Secret and Client Id :)

If Instagram does not return anything after proper configuration of the code, please read this -- https://www.instagram.com/developer/review/

• Fetch user feed by username.
• Fetch Instagram posts by hashtag.
• Save the data in a custom post type ( on demand ).

Include the instagram-helper.php file in your functions.php. At this point, you need to create a $client using the Factory class. The $client takes care of the authentication process:
$client = Instagram_Helper\Factory::create( 'client', $configuration );

The $configuration array should look like this:

$configuration = array(  
    'user_name'     => 'instagram_user_name',  
    'client_id'     => 'instagram_client_id',  
    'client_secret' => 'instagram_client_secret',  
`);

The $client object has the following methods:

• get_redirect_uri() -- Returns the redirection URL that should be placed in the Instagram Client Valid redirect URIs field.
• generate_authentication_url() -- Returns the URL that should be visited in order to start the authentication process.
• get_access_token() -- Handles the retrieval of the access token. Should not be used directly.

Once the authentication is completed, you can pull posts from Instagram. To do so, you need to create a $data_manager object, using the Factory.

$data_manager = Instagram_Helper\Factory::create( 'data_manager', $manager_config );

The $manager_config array is optional. It may, however, contain the limit for the request -- $manager_config = array( 'limit' => 5 ) . This will force default limit of 5 entries for all queries.

The $data_manager has the following methods:

• fetch_user_feed( array( 'limit' => 5 ) ) -- Fetches the last 5 posts from the feed of the user, used in the configuration of the $client.
• fetch_hashtag_feed( array( 'limit' => 5, 'hashtag' => 'tag' ) ) -- Fetches the last 5 posts with that hashtag
• get_feed_data() -- Returns the data fetched by the fetch_user_feed or fetch_hashtag_feed methods.
• clear_feed_data() -- Delete the data fetched by the fetch_user_feed or fetch_hashtag_feed methods
• flush_cache() -- Deletes the data transients ( by default, the data is stored in transients ).
• get_transient_lifetime() -- Return the lifetime of the used transients.
• set_transient_lifetime() -- Sets the lifetime of the transients ( this defaults to 300 seconds ).

$client_config = array(
    'user_name'     => 'instagram_user_name',  
    'client_id'     => 'instagram_client_id',  
    'client_secret' => 'instagram_client_secret',
);

$client  = Instagram_Helper\Factory::create( 'client', $client_config );
$data_manager  = Instagram_Helper\Factory::create( 'data_manager', array( 'limit' => 5 ) );

$data_manager->fetch_user_feed();
$feed = $data_manager->get_feed_data(); //the data from instagram in now available in $feed

Sometimes, you would need to save the data from Instagram for later. In order to do this, you can use a posts_store obejct and it's save() method.

$storer = Instagram_Helper\Factory::create( 'posts_store', array( 'update_count' => 2 ) );
$storer->save( $feed );

The update_count specifies how many posts, of the already existing posts, should be updated with new information from Instagram ( this one is still work in progress :) )

If you are using the Carbon Fields library, you can take advantage of the Carbon_Helper.php class. It must be used in conjunction with the $client object.

$client  = Instagram_Helper\Factory::create( 'client', array( 'enable_carbon_support' => true ) );
$carbon_helper = Instagram_Helper\Factory::create( 'carbon_helper', $client );
$carbon_helper->create_options_page();

The create_options_page() method creates a page in the back end, containing fields for all the information needed by the $client. The $client fetches this information on its own, you do not need to do anything.