Add empty amp-form service to kick off work on validation part (#3470)

extensions/amp-form/0.1/amp-form.js

@@ -0,0 +1,32 @@
+/**
+ * Copyright 2016 The AMP HTML Authors. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS-IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import {isExperimentOn} from '../../../src/experiments';
+import {getService} from '../../../src/service';
+
+/** @type {string} */
+const TAG = 'amp-form';
+
+function installAmpForm(win) {
+  return getService(win, 'amp-form', () => {
+    if (isExperimentOn(win, TAG)) {
+      // TODO: Write the implementation of the service.
+    }
+    return {};
+  });
+}
+
+installAmpForm(AMP.win);

extensions/amp-form/0.1/test/test-amp-form.js

@@ -0,0 +1,18 @@
+/**
+ * Copyright 2016 The AMP HTML Authors. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS-IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+describe('amp-form', () => {
+});

extensions/amp-form/amp-form.md

@@ -0,0 +1,81 @@
+<!---
+Copyright 2016 The AMP HTML Authors. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+      http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS-IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+-->
+
+# <a name="`amp-form`"></a> `amp-form`
+
+<table>
+  <tr>
+    <td width="40%"><strong>Description</strong></td>
+    <td>Allow usage of `<form>` and input tags.</td>
+  </tr>
+  <tr>
+    <td width="40%"><strong>Availability</strong></td>
+    <td>Experimental</td>
+  </tr>
+  <tr>
+    <td width="40%"><strong>Required Script</strong></td>
+    <td><code>&lt;script async custom-element="amp-form" src="https://cdn.ampproject.org/v0/amp-form-0.1.js">&lt;/script></code></td>
+  </tr>
+  <tr>
+    <td class="col-fourty"><strong><a href="https://www.ampproject.org/docs/guides/responsive/control_layout.html">Supported Layouts</a></strong></td>
+    <td>N/A</td>
+  </tr>
+  <tr>
+    <td width="40%"><strong>Examples</strong></td>
+    <td><a href="https://github.com/ampproject/amphtml/blob/master/examples/forms.amp.html">forms.amp.html</a></td>
+  </tr>
+</table>
+
+## Behavior
+
+The `amp-form` extension allows the usage of forms and input fields in an AMP document. The extension allows polyfilling
+some of the missing behaviors in browsers.
+
+The `amp-form` extension **MUST** be loaded if you're using `<form>` or any input tags, otherwise your document will be invalid!
+
+Example:
+```html
+<form method="post" action="https://example.com/subscribe" target="_blank">
+    <fieldset>
+        <label>
+            <span>Your name</span>
+            <input type="text" name="name" required>
+        </label>
+        <label>
+            <span>Your email</span>
+            <input type="email" name="email" required>
+        </label>
+        <input type="submit" value="Subscribe">
+    </fieldset>
+</form>
+```
+
+## Attributes
+
+**target**
+__required__
+
+Target attribute of the `<form>` must be either `_blank` or `_top`.
+
+**action**
+__required__
+
+Action must be provided, `https` and is non-cdn link (does **NOT** link to https://cdn.ampproject.org).
+
+All other [form attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/form) are optional.
+
+## Inputs
+Both `<input type=file>` and `<input type=password>` are not allowed. (This might be reconsidered in the future - please let us know if you require these and use cases).

gulpfile.js

@@ -65,6 +65,7 @@ function buildExtensions(options) {
   buildExtension('amp-fit-text', '0.1', true, options);
   buildExtension('amp-fx-flying-carpet', '0.1', true, options);
   buildExtension('amp-font', '0.1', false, options);
+  buildExtension('amp-form', '0.1', false, options);
   buildExtension('amp-iframe', '0.1', false, options);
   buildExtension('amp-image-lightbox', '0.1', true, options);
   buildExtension('amp-instagram', '0.1', false, options);

tools/experiments/experiments.js

@@ -91,6 +91,11 @@ const EXPERIMENTS = [
     name: 'Global document form submit handler',
     spec: 'https://github.com/ampproject/amphtml/issues/3343',
   },
+  {
+    id: 'amp-form',
+    name: 'AMP Form Extension',
+    spec: 'https://github.com/ampproject/amphtml/issues/3343',
+  },
 ];