Utilizing the WP REST API

Throughout this presentation Rachel will teach us how to leverage the WP REST API for a multitude of different projects. We’ll start with installing and activation the API itself (and important place to begin), and cover some of the caveats that go along with running an API from a publicly-accessible server. From here we’ll look at what kinds of data are available to you and how you can access them, both from your own site and from any other site with the API enabled.

Once we know how to interact with the core API methods we’re going to dive in to manipulating and extending the data that they return. Maybe you need a bit more information about a post… maybe you want to provide a bit less. Good news, there are hooks for that! After that we’ll look at creating our own custom endpoints. The REST API has been specifically written (and re-written) with extensibility in mind.

By the end of this presentation you’ll have enough working knowledge of the WP REST API that you’ll be able to immediately begin using it across any of your WordPress projects.

More information:
http://wpsessions.com/sessions/utilizing-the-wp-rest-api/

Transcript

1. Rachel Baker
   Lead Developer : WP REST API Project
   Lead Engineer: The Wirecutter
   Utilizing the
   

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2. Getting
   Started
   

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3. Install the Plugin
   $ git clone https://github.com/WP-API/WP-API.git wp-rest-api
   Or download the latest v2.0 Beta release
   Clone the develop branch from Github into your plugins directory
   https://github.com/WP-API/WP-API/releases
   

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4. Available Endpoints
   

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5. Embed Related Data
   

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6. Embed the _links
   https://example.com/wp-json/wp/v2/posts/1?_embed
   "_links": {
   …
   "author": [
   {
   "embeddable": true,
   "href": "http://local.wpapi.dev/wp-json/wp/v2/users/2"
   }
   ],
   …
   Hypermedia Application Language
   HAL
   

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7. Display
   Responses
   

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8. Posts Collection
   

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9. Using jQuery
   ( function( $, _ ) {
   var apiUrl = $( 'link[rel="https://github.com/WP-API/WP-API"]' ).attr( 'href' ),
   $el = $( '#js-data' ),
   tmpl = '<%= title %><%= content %>';
   $.get( apiUrl + '/wp/v2/posts', function( data ) {
   for ( var key in data ) {
   var output = {
   id : data[ key ].id,
   title : data[ key ].title.rendered,
   content : data[ key ].content.rendered
   },
   $template = $( _.template( tmpl, output ) );
   $el.append( $template );
   }
   });
   })( jQuery, _ );
   and Underscore
   

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10. Using PHP
    $fetch = wp_remote_get( home_url( '/wp-json/wp/v2/posts' ), array() );
    // Add error checking.
    $response_data = wp_remote_retrieve_body( $fetch );
    // Add error checking.
    $items = json_decode( $response_data );
    $output = '';
    foreach ( $items as $data ) {
    $output .= sprintf( '%s%s',
    $data->id,
    $data->title->rendered,
    $data->content->rendered
    );
    }
    echo $output;
    

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11. Custom
    Post Types
    

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12. Include a Post Type
    

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13. Add Events Endpoints
    Using the init action
    function wpsd_add_tribe_events_args() {
    global $wp_post_types;
    $wp_post_types['tribe_events']->show_in_rest = true;
    $wp_post_types['tribe_events']->rest_base = 'tribe_events';
    $wp_post_types['tribe_events']->rest_controller_class = 'WP_REST_Posts_Controller';
    }
    add_action( 'init', 'wpsd_add_tribe_events_args', 30 );
    

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14. Add Events Endpoints
    function wpsd_add_tribe_events_args( $args ) {
    $args['show_in_rest'] = true;
    $args['rest_base'] = 'tribe_events';
    $args['rest_controller_class'] = 'WP_REST_Posts_Controller';
    return $args;
    }
    add_filter( 'tribe_events_register_event_type_args', 'wpsd_add_tribe_events_args' );
    Using the tribe_events_register_event_type_args filter
    

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15. Modifying
    Endpoints
    

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16. Add an Endpoint Field
    

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17. Add Event URL Field
    function wpsd_register_event_url() {
    $schema = array(
    'type' => 'uri',
    'description' => 'URL of the event',
    'context' => array( 'view', 'edit' ),
    );
    register_api_field( 'tribe_events', 'event_url', array(
    'schema' => $schema,
    'get_callback' => 'wpsd_event_url_get_callback',
    'update_callback' => 'wpsd_event_url_update_callback',
    ) );
    }
    add_action( 'rest_api_init', 'wpsd_register_event_url' );
    

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18. Event URL Field Callbacks
    function wpsd_event_url_get_callback( $post_data ) {
    $event_url = get_post_meta( $post_data['id'], '_EventURL', true );
    return esc_url( $event_url );
    }
    function wpsd_event_url_update_callback( $value, $post ) {
    if ( ! is_string( $value ) ) {
    return new WP_Error( 'rest_meta_event_url_invalid',
    __( 'The event_url value is expected to be a string.' ),
    array( 'status' => 403 )
    );
    }
    $value = esc_url_raw( $value );
    $update = update_post_meta( $post->ID, '_EventURL', $value );
    // Add error checking.
    return $update;
    }
    

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19. Filter Response Data
    

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20. Remove Ping Status
    function wpsd_remove_ping_status( $response ) {
    if ( ! current_user_can( 'edit_posts' ) ) {
    unset( $response->data['ping_status'] );
    }
    return $response;
    }
    add_filter( 'rest_prepare_post', 'wpsd_remove_ping_status' );
    

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21. Custom
    Endpoints
    

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22. Register a Route
    

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23. Register Options Routes
    function wpsd_add_options_routes() {
    $collection_args = array(
    'methods' => WP_REST_Server::READABLE,
    'callback' => 'wpsd_get_options',
    'permission_callback' => 'wpsd_options_permission_check',
    );
    $single_args = array(
    'methods' => WP_REST_Server::READABLE,
    'callback' => 'wpsd_get_option',
    'permission_callback' => 'wpsd_options_permission_check',
    );
    register_rest_route( 'wps_demo/v1', '/options', $collection_args );
    register_rest_route( 'wps_demo/v1', '/options/(?P[\w-]+)', $single_args );
    }
    add_action( 'rest_api_init', 'wpsd_add_options_routes' );
    Just an example of how to create your own route. Do NOT re-use this code.
    

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24. Check Route Permissions
    function wpsd_options_permission_check( $request ) {
    if ( current_user_can( 'manage_options' ) ) {
    return true;
    }
    return new WP_Error( 'wpsd_options_access_denied',
    __( 'Shame on you! You should not be here.' ),
    array( 'status' => 403 )
    );
    }
    

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25. Handle Collection Request
    function wpsd_get_options( $request ) {
    $all_options = wp_load_alloptions();
    $response = rest_ensure_response( $all_options );
    $response->add_link( 'self', rest_url( '/wps_demo/v1/options' ) );
    return $response;
    }
    Loading all the options like this is BAD! This is only an example.
    

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26. Handle Item Request
    function wpsd_get_option( $request ) {
    $key = sanitize_key( $request['key'] );
    $option = array();
    $option[ $key ] = get_option( $key );
    // Add error handling.
    $response = rest_ensure_response( $option );
    $response->add_link( 'self', rest_url( '/wps_demo/v1/options/' . $key ) );
    $response->add_link( 'collection', rest_url( '/wps_demo/v1/options/' ) );
    return $response;
    }
    

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27. Wrapping
    Up
    

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28. Version 2.0 Beta 2
    Release Date:
    May 28, 2015
    https://github.com/WP-API/WP-API
    

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29. https://speakerdeck.com/rachelbaker/utilizing-the-wp-rest-api
    Thank You!
    Slides:
    

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