import java.io.IOException;
import java.io.PrintWriter;
+import java.util.HashMap;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import org.cacert.gigi.GigiApiException;
import org.cacert.gigi.localisation.Language;
+import org.cacert.gigi.pages.Page;
import org.cacert.gigi.util.RandomToken;
/**
*/
public abstract class Form implements Outputable {
+ public static class PermamentFormException extends RuntimeException {
+
+ public PermamentFormException(GigiApiException cause) {
+ super(cause);
+ }
+
+ @Override
+ public synchronized GigiApiException getCause() {
+ return (GigiApiException) super.getCause();
+ }
+ }
+
+ /**
+ * Encapsulates a (non-failure) outcome of a form.
+ */
+ public static abstract class SubmissionResult {
+
+ public abstract boolean endsForm();
+ }
+
+ /**
+ * The form has finished and the user should see the successful completion
+ * on a regular page.
+ */
+ public static class RedirectResult extends SubmissionResult {
+
+ private final String target;
+
+ public RedirectResult(String target) {
+ this.target = target;
+ }
+
+ @Override
+ public boolean endsForm() {
+ return true;
+ }
+
+ }
+
+ /**
+ * The form has not finished and should be re-emitted, however no error
+ * occurred.
+ */
+ public static class FormContinue extends SubmissionResult {
+
+ @Override
+ public boolean endsForm() {
+ return false;
+ }
+ }
+
+ /**
+ * The form has successfully finished and a message should be emitted on a
+ * stateful page.
+ */
+ public static class SuccessMessageResult extends SubmissionResult {
+
+ private final Outputable message;
+
+ public SuccessMessageResult(Outputable message) {
+ this.message = message;
+ }
+
+ @Override
+ public boolean endsForm() {
+ return true;
+ }
+ }
+
public static final String CSRF_FIELD = "csrf";
+ public static final String SUBMIT_RESULT = "form-submit-result";
+
private final String csrf;
private final String action;
/**
* Update the forms internal state based on submitted data.
*
- * @param out
- * the stream to the user.
* @param req
* the request to take the initial data from.
* @return true, iff the form succeeded and the user should be redirected.
* @throws GigiApiException
- * if internal operations went wrong.
+ * if form data had problems or operations went wrong.
+ */
+ public abstract SubmissionResult submit(HttpServletRequest req) throws GigiApiException;
+
+ public boolean submitExceptionProtected(HttpServletRequest req, HttpServletResponse resp) throws IOException {
+ try {
+ SubmissionResult res = submit(req);
+ req.setAttribute(SUBMIT_RESULT, res);
+ if (res instanceof RedirectResult) {
+ resp.sendRedirect(((RedirectResult) res).target);
+ return true;
+ }
+ if (res.endsForm()) {
+ HttpSession hs = req.getSession();
+ hs.removeAttribute("form/" + getClass().getName() + "/" + csrf);
+ }
+ return false;
+ } catch (PermamentFormException e) {
+ req.setAttribute(SUBMIT_RESULT, e);
+ return false;
+ } catch (GigiApiException e) {
+ req.setAttribute(SUBMIT_RESULT, e);
+ return false;
+ }
+ }
+
+ /**
+ * Prints any errors in any form submits on this request.
+ *
+ * @param req
+ * The request to extract the errors from.
+ * @param out
+ * the output stream to the user to write the errors to.
+ * @return true if no permanent errors occurred and the form should be
+ * reprinted (and it has not already been successfully submitted)
*/
- public abstract boolean submit(PrintWriter out, HttpServletRequest req) throws GigiApiException;
+ public static boolean printFormErrors(HttpServletRequest req, PrintWriter out) {
+ Object o = req.getAttribute(SUBMIT_RESULT);
+ if (o != null && (o instanceof PermamentFormException)) {
+ ((PermamentFormException) o).getCause().format(out, Page.getLanguage(req));
+ return false;
+ }
+ if (o != null && (o instanceof GigiApiException)) {
+ ((GigiApiException) o).format(out, Page.getLanguage(req));
+ return true;
+ }
+ if (o != null && (o instanceof FormContinue)) {
+ return true;
+ }
+ if (o != null && (o instanceof SuccessMessageResult)) {
+ Outputable message = ((SuccessMessageResult) o).message;
+ if (message != null) {
+ out.println("<div class='alert alert-success'>");
+ message.output(out, Page.getLanguage(req), new HashMap<String, Object>());
+ out.println("</div>");
+ }
+ return false;
+ }
+ return true;
+ }
protected String getCsrfFieldName() {
return CSRF_FIELD;