Issue 848: Allow theme support of canonical AMP

amp.php

@@ -5,7 +5,7 @@
  * Plugin URI: https://github.com/automattic/amp-wp
  * Author: Automattic
  * Author URI: https://automattic.com
- * Version: 0.6-alpha
+ * Version: 0.7-alpha
  * Text Domain: amp
  * Domain Path: /languages/
  * License: GPLv2 or later
@@ -15,7 +15,7 @@
 
 define( 'AMP__FILE__', __FILE__ );
 define( 'AMP__DIR__', dirname( __FILE__ ) );
-define( 'AMP__VERSION', '0.6-alpha' );
+define( 'AMP__VERSION', '0.7-alpha' );
 
 require_once AMP__DIR__ . '/includes/class-amp-autoloader.php';
 AMP_Autoloader::register();
@@ -117,6 +117,15 @@ function amp_force_query_var_value( $query_vars ) {
 	return $query_vars;
 }
 
+/**
+ * Conditionally add AMP actions or render the 'paired mode' template(s).
+ *
+ * If the request is for an AMP page and this is in 'canonical mode,' redirect to the non-AMP page.
+ * It won't need this plugin's template system, nor the frontend actions like the 'rel' link.
+ *
+ * @since 0.2
+ * @return void
+ */
 function amp_maybe_add_actions() {
 	if ( ! is_singular() || is_feed() ) {
 		return;
@@ -128,7 +137,7 @@ function amp_maybe_add_actions() {
 	global $wp_query;
 	$post = $wp_query->post;
 
-	$supports = post_supports_amp( $post );
+	$supports = post_supports_amp( $post ) && ! amp_is_canonical();
 
 	if ( ! $supports ) {
 		if ( $is_amp_endpoint ) {
@@ -145,6 +154,31 @@ function amp_maybe_add_actions() {
 	}
 }
 
+/**
+ * Whether this is in 'canonical mode.'
+ *
+ * Themes can register support for this with `add_theme_support( 'amp' )`.
+ * Then, this will change the plugin from 'paired mode,' and it won't use its own templates.
+ * Nor output frontend markup like the 'rel' link. If the theme registers support for AMP with:
+ * `add_theme_support( 'amp', array( 'template_path' => get_template_directory() . 'my-amp-templates/' ) )`
+ * it will retain 'paired mode.
+ *
+ * @return boolean Whether this is in AMP 'canonical mode'.
+ */
+function amp_is_canonical() {
+	$support = get_theme_support( 'amp' );
+	if ( true === $support ) {
+		return true;
+	}
+	if ( is_array( $support ) ) {
+		$args = array_shift( $support );
+		if ( empty( $args['template_path'] ) ) {
+			return true;
+		}
+	}
+	return false;
+}
+
 function amp_load_classes() {
 	_deprecated_function( __FUNCTION__, '0.6' );
 }
@@ -225,10 +259,16 @@ function amp_render_post( $post ) {
 /**
  * Bootstraps the AMP customizer.
  *
+ * Uses the priority of 12 for the 'after_setup_theme' action.
+ * Many themes run `add_theme_support()` on the 'after_setup_theme' hook, at the default priority of 10.
+ * And that function's documentation suggests adding it to that action.
+ * So this enables themes to `add_theme_support( 'amp' )`.
+ * And `amp_init_customizer()` will be able to recognize theme support by calling `amp_is_canonical()`.
+ *
  * @since 0.4
  */
 function _amp_bootstrap_customizer() {
-	add_action( 'after_setup_theme', 'amp_init_customizer' );
+	add_action( 'after_setup_theme', 'amp_init_customizer', 12 );
 }
 add_action( 'plugins_loaded', '_amp_bootstrap_customizer', 9 ); // Should be hooked before priority 10 on 'plugins_loaded' to properly unhook core panels.
 

assets/js/amp-post-meta-box.js

@@ -18,6 +18,7 @@ var ampPostMetaBox = ( function( $ ) {
 		 * @since 0.6
 		 */
 		data: {
+			canonical: false,
 			previewLink: '',
 			disabled: false,
 			statusInputName: '',
@@ -58,7 +59,7 @@ var ampPostMetaBox = ( function( $ ) {
 	component.boot = function boot( data ) {
 		component.data = data;
 		$( document ).ready( function() {
-			if ( ! component.data.disabled ) {
+			if ( ! component.data.disabled && ! component.data.canonical ) {
 				component.addPreviewButton();
 			}
 			component.listen();

composer.json

@@ -4,5 +4,5 @@
     "homepage": "https://github.com/Automattic/amp-wp",
     "type": "wordpress-plugin",
     "license": "GPL-2.0",
-    "version": "0.6.0"
+    "version": "0.7.0"
 }

includes/admin/class-amp-post-meta-box.php

@@ -122,6 +122,7 @@ public function enqueue_admin_assets() {
 		wp_add_inline_script( self::ASSETS_HANDLE, sprintf( 'ampPostMetaBox.boot( %s );',
 			wp_json_encode( array(
 				'previewLink'     => esc_url_raw( add_query_arg( AMP_QUERY_VAR, '', get_preview_post_link( $post ) ) ),
+				'canonical'       => amp_is_canonical(),
 				'disabled'        => (bool) get_post_meta( $post->ID, self::DISABLED_POST_META_KEY, true ) || ! $this->is_amp_available( $post ),
 				'statusInputName' => self::STATUS_INPUT_NAME,
 				'l10n'            => array(
@@ -142,6 +143,8 @@ public function render_status( $post ) {
 			isset( $post->ID )
 			&&
 			current_user_can( 'edit_post', $post->ID )
+			&&
+			! amp_is_canonical()
 		);
 
 		if ( true !== $verify ) {

includes/admin/functions.php

@@ -15,8 +15,16 @@
 
 /**
  * Sets up the AMP template editor for the Customizer.
+ *
+ * If this is in AMP canonical mode, exit.
+ * There's no need for the 'AMP' Customizer panel,
+ * And this does not need to toggle between the AMP and normal display.
  */
 function amp_init_customizer() {
+	if ( amp_is_canonical() ) {
+		return;
+	}
+
 	// Fire up the AMP Customizer.
 	add_action( 'customize_register', array( 'AMP_Template_Customizer', 'init' ), 500 );
 

package.json

@@ -6,7 +6,7 @@
   "type": "git",
   "url": "https://github.com/Automattic/amp-wp.git"
  },
- "version": "0.6.0",
+ "version": "0.7.0",
  "license": "GPL-2.0+",
  "private": true,
  "devDependencies": {

readme.md

@@ -55,6 +55,9 @@ Follow along with or [contribute](https://github.com/Automattic/amp-wp/blob/deve
 
 ## Changelog ##
 
+### 0.7 (unreleased) ###
+- Add support for canonical AMP.
+
 ### 0.6 (unreleased) ###
 - Add: support for the "page" post type, except when used as homepage or page for posts. A new `page.php` is introduced with template parts factored out (`html-start.php`, `header.php`, `footer.php`, `html-end.php`) and re-used from `single.php`. Note that AMP URLs will end in `?amp` instead of `/amp/`. See [#825](https://github.com/Automattic/amp-wp/pull/825). Props technosailor, ThierryA, westonruter.
 - Add: AMP post preview button alongside non-AMP preview button. See [#813](https://github.com/Automattic/amp-wp/pull/813). Props ThierryA, westonruter.

readme.txt

@@ -38,6 +38,10 @@ Follow along with or [contribute](https://github.com/Automattic/amp-wp/blob/deve
 
 == Changelog ==
 
+= 0.7 (unreleased) =
+
+- Add support for canonical AMP.
+
 = 0.6 (unreleased) =
 
 - Add: support for the "page" post type, except when used as homepage or page for posts. A new `page.php` is introduced with template parts factored out (`html-start.php`, `header.php`, `footer.php`, `html-end.php`) and re-used from `single.php`. Note that AMP URLs will end in `?amp` instead of `/amp/`. See [#825](https://github.com/Automattic/amp-wp/pull/825). Props technosailor, ThierryA, westonruter.

tests/test-amp.php

@@ -0,0 +1,39 @@
+<?php
+/**
+ * Tests for amp.php.
+ *
+ * @package AMP
+ */
+
+/**
+ * Tests for amp.php.
+ */
+class Test_AMP extends WP_UnitTestCase {
+
+	/**
+	 * Tear down and clean up.
+	 */
+	public function tearDown() {
+		parent::tearDown();
+		remove_theme_support( 'amp' );
+	}
+
+	/**
+	 * Test amp_is_canonical().
+	 *
+	 * @covers amp_is_canonical()
+	 */
+	public function test_amp_is_canonical() {
+		remove_theme_support( 'amp' );
+		$this->assertFalse( amp_is_canonical() );
+
+		add_theme_support( 'amp' );
+		$this->assertTrue( amp_is_canonical() );
+
+		remove_theme_support( 'amp' );
+		add_theme_support( 'amp', array(
+			'template_path' => get_template_directory() . 'amp-templates/',
+		) );
+		$this->assertFalse( amp_is_canonical() );
+	}
+}

tests/test-class-amp-meta-box.php

@@ -79,10 +79,19 @@ public function test_render_status() {
 		wp_set_current_user( $this->factory->user->create( array(
 			'role' => 'administrator',
 		) ) );
+		$amp_status_markup = '<div class="misc-pub-section misc-amp-status"';
 
+		// This is in AMP 'canonical mode,' so it shouldn't have the AMP status.
+		add_theme_support( 'amp' );
 		ob_start();
 		$this->instance->render_status( $post );
-		$this->assertContains( '<div class="misc-pub-section misc-amp-status"', ob_get_clean() );
+		$this->assertNotContains( $amp_status_markup, ob_get_clean() );
+
+		// This is not in AMP 'canonical mode'.
+		remove_theme_support( 'amp' );
+		ob_start();
+		$this->instance->render_status( $post );
+		$this->assertContains( $amp_status_markup, ob_get_clean() );
 
 		remove_post_type_support( 'post', AMP_QUERY_VAR );