[Haskell-cafe] web-routes and forms

Corentin Dupont corentin.dupont at gmail.com
Sat Jan 22 22:19:56 CET 2011


Hello Jeremy,
Yes it would be fine to use solution 1, but I just don't figured how to mix
web routes and forms.

My forms are like that:
loginForm :: RoutedNomicServer Html
loginForm = do
   ok $ H.form ! A.method "POST" ! A.action "/postLogin" ! enctype
"multipart/form-data;charset=UTF-8"  $ do
       H.label ! for "login" $ "Login"
       input ! type_ "text" ! name "login" ! A.id "login" ! tabindex "1" !
accesskey "L"
       H.label ! for "password" $ "Password"
       input ! type_ "text" ! name "password" ! A.id "password" ! tabindex
"2" ! accesskey "P"
       input ! type_  "submit" ! tabindex "3" ! accesskey "S" ! value "Enter
Nomic!"


And are decoded using a FromData:

instance FromData LoginPass where
  fromData = do
    login  <- look "login" `mplus` (error "need login")
    password <- look "password" `mplus` (error "need password")
    return $ LoginPass login password

How this can go inside web routes? I cannot pass the parameters in the URL
(here login and password), can I?

Thanks,
Corentin

On Sat, Jan 22, 2011 at 9:49 PM, Jeremy Shaw <jeremy at n-heptane.com> wrote:

> Hello,
>
> I believe you problem is because you are trying to use 'dir' inside
> RouteT after you have already consumed and decode the path info using
> implSite.
>
> There are two solutions here:
>
>  1. just use web-routes for all your URLs instead of using a mixture
> of type-safe routes and 'dir'.
>  2. put the calls to dir outside the call to implSite.
>
> For example, something like,
>
>   simpleHTTP nullConf $ msum [ dir "Login" $ loginPage,
>                                                , dir "postLogin" $
> postLogin
>                                                 , implSite
> "http://localhost:8000/" "" (nomicSite sh)
>                                                 ]
>
> You to do that, you would also need to modified loginPage and
> postLogin to not be in the RoutedNomicServer monad. Since they do not
> appear to use the RouteT stuff anyway, that should not be hard ?
>
> But, personally, I would just choose option #1. Can you explain why
> you thought it was better to mix the web-routes stuff with the 'dir'
> style guards? Maybe there is a short coming in web-routes that needs
> to be addressed ?
>
> - jeremy
>
> On Fri, Jan 21, 2011 at 2:33 PM, Corentin Dupont
> <corentin.dupont at gmail.com> wrote:
> > Hello Jeremy,
> > I'm still trying to integrate web routes, but there is one thing I don't
> > understand:
> > how to deal with multiple forms?
> >
> > In my former application, each forms used to redirect to a subdirectory
> of
> > the web site, and an appropriate handler was waiting there.
> > But now with web routes I don't see how to do that.
> > I've tried to push down the decision over subdirectories (with the guard
> > "dir") inside the RouteT monad:
> >
> > type NomicServer       = ServerPartT IO
> > type RoutedNomicServer = RouteT PlayerCommand NomicServer
> >
> > nomicSite :: ServerHandle -> Site PlayerCommand (NomicServer Html)
> > nomicSite sh = setDefault (Noop 0) Site {
> >       handleSite         = \f url -> unRouteT (routedNomicHandle sh url)
> f
> >     , formatPathSegments = \u -> (toPathSegments u, [])
> >     , parsePathSegments  = parseSegments fromPathSegments
> > }
> >
> > routedNomicHandle :: ServerHandle -> PlayerCommand -> RoutedNomicServer
> Html
> > routedNomicHandle sh pc = do
> >    d <- liftRouteT $ liftIO getDataDir
> >    msum [dir "Login" $ loginPage,
> >          dir "postLogin" $ postLogin,
> >          --nullDir >> fileServe [] d,
> >          dir "NewRule" $ newRule sh,
> >          dir "NewGame" $ newGameWeb sh,
> >          dir "Nomic" $ routedNomicCommands sh pc]
> >
> >
> > routedNomicCommands :: ServerHandle -> PlayerCommand -> RoutedNomicServer
> > Html
> > routedNomicCommands sh (Noop pn)                   = nomicPageComm pn sh
> > (return ())
> > routedNomicCommands sh (JoinGame pn game)          = nomicPageComm pn sh
> > (joinGame game pn)
> > routedNomicCommands sh (LeaveGame pn)              = nomicPageComm pn sh
> > (leaveGame pn)
> > routedNomicCommands sh (SubscribeGame pn game)     = nomicPageComm pn sh
> > (subscribeGame game pn)
> > routedNomicCommands sh (UnsubscribeGame pn game)   = nomicPageComm pn sh
> > (unsubscribeGame game pn)
> > routedNomicCommands sh (Amend pn)                  = nomicPageComm pn sh
> > (amendConstitution pn)
> > routedNomicCommands sh (DoAction pn an ar)         = nomicPageComm pn sh
> > (doAction' an ar pn)
> > routedNomicCommands sh (NewRule pn name text code) = nomicPageComm pn sh
> > (submitRule name text code pn)
> > routedNomicCommands sh (NewGame pn game)           = nomicPageComm pn sh
> > (newGame game pn)
> >
> >
> > loginPage :: RoutedNomicServer Html
> > loginPage = do
> >    l <- loginForm
> >    ok $ H.html $ do
> >       H.head $ do
> >         H.title (H.string "Login to Nomic")
> >         H.link ! rel "stylesheet" ! type_ "text/css" ! href
> > "/static/css/nomic.css"
> >         H.meta ! A.httpEquiv "Content-Type" ! content
> > "text/html;charset=utf-8"
> >         H.meta ! A.name "keywords" ! A.content "Nomic, game, rules,
> Haskell,
> > auto-reference"
> >       H.body $ do
> >         H.div ! A.id "container" $ do
> >            H.div ! A.id "header" $ "Login to Nomic"
> >            H.div ! A.id "login" $ l
> >            H.div ! A.id "footer" $ "footer"
> >
> > loginForm :: RoutedNomicServer Html
> > loginForm = do
> >    ok $ H.form ! A.method "POST" ! A.action "/postLogin" ! enctype
> > "multipart/form-data;charset=UTF-8"  $ do
> >       H.label ! for "login" $ "Login"
> >       input ! type_ "text" ! name "login" ! A.id "login" ! tabindex "1" !
> > accesskey "L"
> >       H.label ! for "password" $ "Password"
> >       input ! type_ "text" ! name "password" ! A.id "password" ! tabindex
> > "2" ! accesskey "P"
> >       input ! type_  "submit" ! tabindex "3" ! accesskey "S" ! value
> "Enter
> > Nomic!"
> >
> > postLogin :: RoutedNomicServer Html
> > postLogin = do
> >   methodM POST -- only accept a post method
> >   mbEntry <- getData -- get the data
> >   case mbEntry of
> >     Nothing -> error $ "error: postLogin"
> >     Just (LoginPass login password)  -> do
> >       mpn <- liftRouteT $ liftIO $ newPlayerWeb login password
> >       case mpn of
> >          Just pn -> do
> >             link <- showURL $ Noop pn
> >             seeOther link $ string "Redirecting..."
> >          Nothing -> seeOther ("/Login?status=fail" :: String) $ string
> > "Redirecting..."
> >
> > launchWebServer :: ServerHandle -> IO ()
> > launchWebServer sh = do
> >    putStrLn "Starting web server...\nTo connect, drive your browser to
> > \"http://localhost:8000/Login\ <http://localhost:8000/Login%5C>""
> >    simpleHTTP nullConf $ implSite "http://localhost:8000/" "" (nomicSite
> sh)
> >
> >
> > But when I drive my browser to "http://localhost:8000/Login/", happstack
> > tell me there is nothing here.
> > Am I doing it right? If yes, I must have made a mistake.
> > (as you can see I'm still far from putting in disgestive functors ;)
> >
> > If you need, the complete application can be found here (see file
> Web.hs):
> > https://github.com/cdupont/Nomic
> >
> > Thanks,
> > Corentin
> >
> > On Wed, Jan 19, 2011 at 5:12 PM, Corentin Dupont <
> corentin.dupont at gmail.com>
> > wrote:
> >>
> >> Thanks Jeremy.
> >> I had it to work now ;)
> >>
> >> Corentin
> >>
> >> On Tue, Jan 18, 2011 at 6:01 PM, Jeremy Shaw <jeremy at n-heptane.com>
> wrote:
> >>>
> >>> Hello,
> >>>
> >>> trhsx will be installed in ~/.cabal/bin, so you will need to add that
> >>> to your PATH.
> >>>
> >>> In order to use the demo code I provided you would need the latest
> >>> happstack from darcs because it contains a few differences in the API.
> >>> The code can be made to work with what is on hackage though.
> >>>
> >>> The submit issue is actually a bug in digestive-functors-blaze. The
> >>> return type should be, Form m i e BlazeFormHtml (). jaspervdj is going
> >>> to patch it and upload a new version.
> >>>
> >>> - jeremy
> >>>
> >>>
> >>> On Thu, Jan 13, 2011 at 2:40 PM, Corentin Dupont
> >>> <corentin.dupont at gmail.com> wrote:
> >>> > Hello,
> >>> >
> >>> > I'm using the combination happstack + digestive-functors + web-routes
> +
> >>> > blazeHTML.
> >>> > I'm not finding any examples on the net...
> >>> >
> >>> > I've tried to adapt your example (thanks):
> >>> >
> >>> > type NomicForm a = HappstackForm IO String BlazeFormHtml a
> >>> >
> >>> > demoForm :: NomicForm (Text, Text)
> >>> > demoForm =
> >>> >     (,) <$> ((TDB.label "greeting: " ++> inputNonEmpty Nothing) <*
> br)
> >>> >         <*> ((TDB.label "noun: "     ++> inputNonEmpty Nothing) <*
> br)
> >>> >         <*  (submit "submit")
> >>> >     where
> >>> >       br :: NomicForm ()
> >>> >       br = view H.br
> >>> >       -- make sure the fields are not blank, show errors in line if
> >>> > they are
> >>> >       inputNonEmpty :: Maybe Text -> NomicForm Text
> >>> >       inputNonEmpty v =
> >>> >           (inputText v `validate` (TD.check "You can not leave this
> >>> > field
> >>> > blank." (not . T.null)) <++ errors)
> >>> >
> >>> >
> >>> > But I've got a problem on submit and inputText. I don't see how they
> >>> > are
> >>> > compatible with HappstackForm.
> >>> > NomicForm a reduces to:
> >>> > Form (ServerPartT IO) Input String BlazeFormHtml a
> >>> >
> >>> > whereas the type of submit is:
> >>> >
> >>> > submit :: Monad m
> >>> >
> >>> >        => String                            -- ^ Text on the submit
> >>> > button
> >>> >
> >>> >        -> Form m String e BlazeFormHtml ()  -- ^ Submit button
> >>> >
> >>> >
> >>> > Maybe I miss some instance?
> >>> >
> >>> > BTW, I also tried to execute your exemple, but I can't install some
> >>> > packages.
> >>> >
> >>> >> cabal install digestive-functors-hsp
> >>> >
> >>> > cabal: Unknown build tool trhsx
> >>> >
> >>> > Whereas trhsx is in my PATH (under linux).
> >>> >
> >>> > You said I need the latest happstack from darcs, why?
> >>> >
> >>> > Cheers,
> >>> > Corentin
> >>> >
> >>> > On Sun, Jan 9, 2011 at 8:36 PM, Jeremy Shaw <jeremy at n-heptane.com>
> >>> > wrote:
> >>> >>
> >>> >> Hello,
> >>> >>
> >>> >> newRule also needs to have the type, RoutedNomicServer. The
> >>> >> transformation of RoutedNomicServer into NomicServer is done in the
> >>> >> handleSite function. Something like this:
> >>> >>
> >>> >>
> >>> >> nomicSpec :: ServerHandle -> Site Route (ServerPartT IO Response)
> >>> >> nomicSpec sh =
> >>> >>      Site { handleSite          = \f url -> unRouteT (nomicSite sh
> >>> >> url) f
> >>> >>             ...
> >>> >>
> >>> >> main =
> >>> >>    do ...
> >>> >>      simpleHTTP nullConf $ siteImpl (nomicSpec sh)
> >>> >>
> >>> >> Or something like that -- it's hard to tell exactly what is going on
> >>> >> in your app based on the snippets you provided.
> >>> >>
> >>> >> Also, I highly recommend using digestive functors instead of
> formlets.
> >>> >> It is the successor to formlets. Same core idea, better
> implementation
> >>> >> and actively maintained.
> >>> >>
> >>> >> I have attached a quick demo of using:
> >>> >>
> >>> >> happstack+digestive-functors+web-routes+HSP
> >>> >>
> >>> >> To use it you will need the latest happstack from darcs plus:
> >>> >>
> >>> >>  hsp
> >>> >>  web-routes
> >>> >>  web-routes-hsp
> >>> >>  web-routes-happstack
> >>> >>  web-routes-mtl
> >>> >>  digestive-functors
> >>> >>  digestive-functors-hsp
> >>> >>
> >>> >> I plan to clean up this example and document it better in the crash
> >>> >> course for the upcoming release. Clearly things like the FormInput
> >>> >> instance and the formPart function belong a library.
> >>> >>
> >>> >> let me know if you have more questions.
> >>> >> - jeremy
> >>> >>
> >>> >> On Sat, Jan 8, 2011 at 6:44 PM, Corentin Dupont
> >>> >> <corentin.dupont at gmail.com> wrote:
> >>> >> > Hello,
> >>> >> >
> >>> >> > I have difficulties mixing web-routes and forms:
> >>> >> > I have put routes in all my site, except for forms which remains
> >>> >> > with
> >>> >> > the
> >>> >> > type ServerPartT IO Response.
> >>> >> > How to make them work together?
> >>> >> >
> >>> >> > I have:
> >>> >> > type NomicServer             = ServerPartT IO
> >>> >> > type RoutedNomicServer = RouteT PlayerCommand NomicServer
> >>> >> >
> >>> >> > newRule :: ServerHandle -> NomicServer Response
> >>> >> > newRule sh = do
> >>> >> >    methodM POST -- only accept a post method
> >>> >> >    mbEntry <- getData -- get the data
> >>> >> >    case mbEntry of
> >>> >> >       Nothing -> error $ "error: newRule"
> >>> >> >       Just (NewRule name text code pn) -> do
> >>> >> >          html <- nomicPageComm pn sh (submitRule name text code
> pn))
> >>> >> >          ok $ toResponse html
> >>> >> >
> >>> >> >
> >>> >> > nomicPageComm :: PlayerNumber -> ServerHandle -> Comm () ->
> >>> >> > RoutedNomicServer Html
> >>> >> > nomicPageComm pn sh comm =
> >>> >> > (..)
> >>> >> >
> >>> >> >
> >>> >> > launchWebServer :: ServerHandle -> IO ()
> >>> >> > launchWebServer sh = do
> >>> >> >    putStrLn "Starting web server...\nTo connect, drive your
> browser
> >>> >> > to
> >>> >> > \"http://localhost:8000/Login\ <http://localhost:8000/Login%5C>""
> >>> >> >    d <- liftIO getDataDir
> >>> >> >    simpleHTTP nullConf $ mconcat [dir "postLogin" $ postLogin,
> >>> >> >                                   fileServe [] d,
> >>> >> >                                   dir "Login" $ ok $ toResponse $
> >>> >> > loginPage,
> >>> >> >                                   dir "NewRule" $ newRule sh,
> >>> >> >                                   dir "NewGame" $ newGameWeb sh,
> >>> >> >                                   dir "Nomic" $ do
> >>> >> >                                      html <- implSite
> >>> >> > "http://localhost:8000/Nomic/" "" (nomicSite sh)
> >>> >> >                                      ok $ toResponse html
> >>> >> >                                   ]
> >>> >> >
> >>> >> >
> >>> >> > The red line doesn't compile. I don't know how to transform a
> >>> >> > RoutedNomicServer into a NomicServer.
> >>> >> >
> >>> >> > For the future I intend to use formlets: is these some examples of
> >>> >> > programs
> >>> >> > using happstack + web-routes + formlets?
> >>> >> >
> >>> >> > Thanks,
> >>> >> > Corentin
> >>> >> >
> >>> >> >
> >>> >> >
> >>> >> >
> >>> >> > On Fri, Jan 7, 2011 at 5:10 PM, Jeremy Shaw <jeremy at n-heptane.com
> >
> >>> >> > wrote:
> >>> >> >>
> >>> >> >> Hello,
> >>> >> >>
> >>> >> >> The [(String, String)] argument is for adding query parameters.
> >>> >> >>
> >>> >> >> > encodePathInfo ["foo", "bar", "baz"] [("key","value")]
> >>> >> >>
> >>> >> >> "foo/bar/baz?key=value"
> >>> >> >>
> >>> >> >> Instead of showURL you would use showURLParams.
> >>> >> >>
> >>> >> >> hope this helps!d
> >>> >> >> - jeremy
> >>> >> >>
> >>> >> >> On Fri, Jan 7, 2011 at 8:12 AM, Corentin Dupont
> >>> >> >> <corentin.dupont at gmail.com> wrote:
> >>> >> >> > Hello Jeremy,
> >>> >> >> > I'm using Web routes with happstack.
> >>> >> >> > I'm following this tutorial:
> >>> >> >> >
> http://tutorialpedia.org/tutorials/Happstack+type+safe+URLs.html
> >>> >> >> >
> >>> >> >> > But It seems out of synch with the latest version of
> web-routes:
> >>> >> >> > 0.23.2.
> >>> >> >> > The haddock documentation seems out of date also:
> >>> >> >> >
> >>> >> >> > encodePathInfo :: [String] -> [(String, String)] -> String
> >>> >> >> >
> >>> >> >> > For example:
> >>> >> >> >
> >>> >> >> >  encodePathInfo [\"foo\", \"bar\", \"baz\"]
> >>> >> >> >
> >>> >> >> > "foo/bar/baz"
> >>> >> >> >
> >>> >> >> > And I can't figure out what this [(String, String)] is for ;)
> >>> >> >> >
> >>> >> >> > Thanks,
> >>> >> >> >
> >>> >> >> > Corentin
> >>> >> >> >
> >>> >> >
> >>> >> >
> >>> >
> >>> >
> >>
> >
> >
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.haskell.org/pipermail/haskell-cafe/attachments/20110122/c1b08dea/attachment.htm>


More information about the Haskell-Cafe mailing list