File Content: handler.php <?php add_action( 'wp_ajax_caldera_forms_sendwp_remote_install', 'caldera_forms_sendwp_remote_install_handler' ); function caldera_forms_sendwp_remote_install_handler () { //Security check via senwp_install_nonce $security = check_ajax_referer('sendwp_install_nonce', 'sendwp_nonce', false); if ( ! $security ) { ob_end_clean(); echo json_encode( array( 'error' => true, 'debug' => '!security') ); exit; } else if( ! current_user_can('install_plugins') ) { ob_end_clean(); echo json_encode( array( 'error' => true, 'debug' => '!user_capability') ); exit; } $all_plugins = get_plugins(); $is_sendwp_installed = false; foreach(get_plugins() as $path => $details ) { if(false === strpos($path, '/sendwp.php')) continue; $is_sendwp_installed = true; activate_plugin( $path ); break; } //Display an error message if a connection is activated on the website if( $is_sendwp_installed && sendwp_client_connected() ){ ob_end_clean(); echo json_encode( array( 'error' => true, 'debug' => 'sendwp_connected' ) ); exit; } if( ! $is_sendwp_installed ) { $plugin_slug = 'sendwp'; include_once ABSPATH . 'wp-admin/includes/plugin-install.php'; include_once ABSPATH . 'wp-admin/includes/file.php'; include_once ABSPATH . 'wp-admin/includes/class-wp-upgrader.php'; /* * Use the WordPress Plugins API to get the plugin download link. */ $api = plugins_api( 'plugin_information', array( 'slug' => $plugin_slug, ) ); if ( is_wp_error( $api ) ) { ob_end_clean(); echo json_encode( array( 'error' => esc_html( $api->get_error_message() ), 'debug' => $api ) ); exit; } /* * Use the AJAX Upgrader skin to quietly install the plugin. */ $upgrader = new Plugin_Upgrader( new WP_Ajax_Upgrader_Skin() ); $install = $upgrader->install( $api->download_link ); if ( is_wp_error( $install ) ) { ob_end_clean(); echo json_encode( array( 'error' => esc_html( $install->get_error_message() ), 'debug' => $api ) ); exit; } /* * Activate the plugin based on the results of the upgrader. * @NOTE Assume this works, if the download works - otherwise there is a false positive if the plugin is already installed. */ $activated = activate_plugin( $upgrader->plugin_info() ); } /* * Final check to see if SendWP is available. */ if( ! function_exists('sendwp_get_server_url') ) { ob_end_clean(); echo json_encode( array( 'error' => esc_html__( 'Something went wrong. SendWP was not installed correctly.' ), 'install' => $install, ) ); exit; } echo json_encode( array( 'partner_id' => 2400, 'register_url' => esc_url( sendwp_get_server_url() . '_/signup' ), 'client_name' => esc_attr( sendwp_get_client_name() ), 'client_secret' => esc_attr( sendwp_get_client_secret() ), 'client_redirect' => esc_url( sendwp_get_client_redirect() ), 'client_url' => esc_url( sendwp_get_client_url() ) ) ); exit; } Submit