I found out how I can store JSON data into a custom field. I completely forgot to use add_action.
Here is my answer below I added to functions.php.
You have to add custom field place_id and its value then click 'publish or 'update' for the other fields to populate.
function google_places_data( $post = null ) { if ( ! $post = get_post( $post ) ) return; if ( ! $place_id = get_post_meta( $post->ID, 'place_id', true ) ) return; // No place ID configured for this post if ( $data = get_post_meta( $post->ID, 'place_data', true ) ) { if ( $data->timeout <= current_time( 'timestamp' ) ) $data = null; // Void the cache if it's old } if ( ! $data ) { $args = http_build_query( array( 'key' => 'AIzaSyCarm54WzOXFhXqmEU3rkUorDoa8b3Nzog', // API key 'placeid' => $place_id ) ); $http = wp_remote_get( "https://maps.googleapis.com/maps/api/place/details/json?$args" ); if ( $body = wp_remote_retrieve_body( $http ) ) { if ( $data =@ json_decode( $body ) ) $data->timeout = current_time( 'timestamp' ) + HOUR_IN_SECONDS; // Cache data for 1 hour $place_address = $data->result->formatted_address; $place_lat = $data->result->geometry->location->lat; $place_long = $data->result->geometry->location->lng; $place_phone = '000-000-010'; update_post_meta( $post->ID, 'place_address', $place_address ); update_post_meta( $post->ID, 'place_lat', $place_lat ); update_post_meta( $post->ID, 'place_long', $place_long ); update_post_meta( $post->ID, 'place_phone', $place_phone ); } if ( $data ) { update_post_meta( $post->ID, 'place_data', $data ); } else { echo 'api error'; } } return $data; } add_action( 'save_post', 'google_places_data', 10, 4 );