Includes submit button value into FormData. See liferay#199

src/app/App.js

@@ -450,6 +450,7 @@ class App extends EventEmitter {
 		this.isNavigationPending = false;
 		this.pendingNavigate = null;
 		globals.capturedFormElement = null;
+		globals.capturedFormButtonElement = null;
 		console.log('Navigation done');
 	}
 
@@ -653,6 +654,7 @@ class App extends EventEmitter {
 		}
 
 		globals.capturedFormElement = event.capturedFormElement;
+		globals.capturedFormButtonElement = event.capturedFormButtonElement;
 
 		var navigateFailed = false;
 		try {
@@ -804,6 +806,12 @@ class App extends EventEmitter {
 			return;
 		}
 		event.capturedFormElement = form;
+		const buttonSelector = 'button:not([type]),button[type=submit],input[type=submit]';
+		if (dom.match(globals.document.activeElement, buttonSelector)) {
+			event.capturedFormButtonElement = globals.document.activeElement;
+		} else {
+			event.capturedFormButtonElement = form.querySelector(buttonSelector);
+		}
 		this.maybeNavigate_(form.action, event);
 	}
 

src/screen/RequestScreen.js

@@ -193,26 +193,23 @@ class RequestScreen extends Screen {
 	 * @inheritDoc
 	 */
 	load(path) {
-		var cache = this.getCache();
+		const cache = this.getCache();
 		if (core.isDefAndNotNull(cache)) {
 			return CancellablePromise.resolve(cache);
 		}
-
-		var body = null;
-		var httpMethod = this.httpMethod;
-
-		var headers = new MultiMap();
+		let body = null;
+		let httpMethod = this.httpMethod;
+		const headers = new MultiMap();
 		Object.keys(this.httpHeaders).forEach(header => headers.add(header, this.httpHeaders[header]));
-
 		if (globals.capturedFormElement) {
 			body = new FormData(globals.capturedFormElement);
 			httpMethod = RequestScreen.POST;
 			if (UA.isIeOrEdge) {
 				headers.add('If-None-Match', '"0"');
 			}
 		}
-
-		var requestPath = this.formatLoadPath(path);
+		this.maybeAppendSubmitButtonValue_(body);
+		const requestPath = this.formatLoadPath(path);
 		return Ajax
 			.request(requestPath, httpMethod, body, headers, null, this.timeout)
 			.then(xhr => {
@@ -237,6 +234,18 @@ class RequestScreen extends Screen {
 			});
 	}
 
+	/**
+	 * Adds aditional data to the body of the request in case a submit button
+	 * is captured during form submission.
+	 * @param {!FormData} body The FormData containing the request body.
+	 */
+	maybeAppendSubmitButtonValue_(body) {
+		const button = globals.capturedFormButtonElement;
+		if (body && button && button.name && !button.disabled) {
+			body.append(button.name, button.value);
+		}
+	}
+
 	/**
 	 * The following method tries to extract the response url value by checking
 	 * the custom response header 'X-Request-URL' if proper value is not present

test/screen/RequestScreen.js

@@ -221,6 +221,49 @@ describe('RequestScreen', function() {
 		this.requests[0].respond(200);
 	});
 
+	it('should add submit input button value into request FormData', (done) => {
+		globals.capturedFormElement = globals.document.createElement('form');
+		const submitButton = globals.document.createElement('input');
+		submitButton.name = 'submitButton';
+		submitButton.value = 'Send';
+		globals.capturedFormElement.appendChild(submitButton);
+		var screen = new RequestScreen();
+		screen.load('/url').then(() => {
+			let submitButtonValue;
+			for (let pair of screen.getRequest().requestBody) {
+				if (pair[0] === submitButton.name) {
+					submitButtonValue = pair[1];
+				}
+			}
+			assert.strictEqual(submitButton.value, submitButtonValue);
+			globals.capturedFormElement = null;
+			done();
+		});
+		this.requests[0].respond(200);
+	});
+
+	it('should not add disabled submit input button value into request FormData', (done) => {
+		globals.capturedFormElement = globals.document.createElement('form');
+		const submitButton = globals.document.createElement('input');
+		submitButton.name = 'submitButton';
+		submitButton.value = 'Send';
+		submitButton.disabled = true;
+		globals.capturedFormElement.appendChild(submitButton);
+		var screen = new RequestScreen();
+		screen.load('/url').then(() => {
+			let submitButtonValue;
+			for (let pair of screen.getRequest().requestBody) {
+				if (pair[0] === submitButton.name) {
+					submitButtonValue = pair[1];
+				}
+			}
+			assert.notOk(null, submitButtonValue);
+			globals.capturedFormElement = null;
+			done();
+		});
+		this.requests[0].respond(200);
+	});
+
 	it('should not cache get requests on ie browsers', (done) => {
 		UA.testUserAgent('MSIE'); // Simulates ie user agent
 		var url = '/url';