On Mon, 25 Sep 2017 14:30:54 GMT, Erdem wrote:

I have a post create method: 

void gönderiyiOluştur(HTTPServerRequest istek, HTTPServerResponse yanıt)
{
    render!("gönderiler/oluştur.dt")(yanıt);
}

and a post store method like this: 

void gönderiyiKaydet(HTTPServerRequest istek, HTTPServerResponse yanıt)
{
    auto başlık = istek.form["baslik"];
    auto içerik = istek.form["icerik"];

    bool yayınla = false;

    if (başlık.length > 0)
    {

        Gönderi gönderi = Gönderi(başlık, içerik);

        gönderi.kaydet();
        yanıt.redirect("/");
    }
    else
    {
        yanıt.redirect("/gönderiler/oluştur");
    }
}

I'd like to make basic form validation. For example if input fields are empty it redirects to previous page.

I suppose I should pass some error message to the create method like "baslik field should not be empty" etc..

But since I am quite new to framework I shouldn't figure out. Are there any facilities does the framework offer for form validation.

Erdem

This is the realm of the vibe.web.web module. Using form parameters and the @errorDisplay annotation, the example can be reduced to this: 

import vibe.http.router;
import vibe.http.server;
import vibe.web.web;

class MyWebApp {
    @method(HTTPMethod.get)
    void gönderiyiOluştur(string _error = "")
    {
        // should display _error's contents appropriately if not empty
        render!("gönderiler/oluştur.dt", _error);
    }

    // this causes any exception or parameter validation error to get rendered using gönderiyiOluştur, setting _error appropriately
    @errorDisplay!gönderiyiOluştur
    // "baslik" and "icerik" are automatically read from req.form. They can also be other types, such as integers, and will be validated and converted automatically.
    // Note: the HTTP method defaults to POST here. @method or one of the prefixes like "get" can be used to change this.
    void gönderiyiKaydet(NonEmptyString baslik, string icerik)
    {
        Gönderi gönderi = Gönderi(başlık, içerik);
        gönderi.kaydet();
        yanıt.redirect("/");
    }
}

auto router = new URLRouter;
router.registerWebInterface(new MyWebApp);
listenHTTP(":8080", router);

The validation logic is in the type NonEmptyString, which does not exist in vibe.d itself (there are some predefined validation schemes in vibe.web.validation, though), but can be user defined: 

struct NonEmptyString {
pure nothrow @safe:
    private string m_value;
    private this(string value) { m_value = value; }
    string toString() const { return m_value; }
    alias toString this;

    static Nullable!NonEmptyString fromStringValidate(string str, string* error)
    {
        Nullable!ValidPassword ret;
        if (str.length == 0) *error = "Input must not be empty.";
        else ret = NonEmptyString(str);
        return ret;
    }
}

Disclaimer: This was written off the top of my head. If anything doesn't work, please let me know.