diff --git a/happs-tutorial.cabal b/happs-tutorial.cabal --- a/happs-tutorial.cabal +++ b/happs-tutorial.cabal @@ -1,5 +1,5 @@ Name: happs-tutorial -Version: 0.8.1 +Version: 0.9.0 Synopsis: A Happstack Tutorial that is its own web 2.0-type demo. Description: A nice way to learn how to build web sites with Happstack @@ -46,10 +46,28 @@ MiscMap ControllerStressTests View - ghc-options: -Wall - Build-Depends: base, HStringTemplate, HStringTemplateHelpers, mtl, bytestring, - happstack, containers, pretty, pureMD5, directory, filepath, hscolour, - HTTP, safe, old-time, parsec, happstack-helpers, DebugTraceHelpers, - happstack-server, happstack-data, happstack-ixset, happstack-state + ghc-options: -Wall -O2 + Build-Depends: base + , HStringTemplate >= 0.4.0 && < 0.5.0 + , HStringTemplateHelpers > 0.0.0 && < 1.0.0 + , mtl >= 1.1.0.0 && < 2.0.0.0 + , bytestring >= 0.9.0.0 && < 0.10.0.0 + , happstack >= 0.3 && < 0.4 + , containers >= 0.2.0.0 && < 0.3.0.0 + , pretty >= 1.0.1.0 && < 2 + , pureMD5 >= 1.0.0.0 && < 1.1.0.0 + , directory >= 1.0.0.0 && < 1.1.0.0 + , filepath >= 1.1.0.0 && < 1.2.0.0 + , hscolour >= 1.0 && < 2.0 + , HTTP >= 4000.0.7 && < 4000.0.8 + , safe >= 0.2 && < 0.3 + , old-time >= 1.0.0.0 && < 1.1.0.0 + , parsec >= 2.1.0.0 && < 2.2.0.0 + , happstack-helpers >= 0.30 && < 0.40 + , DebugTraceHelpers >= 0.12 && < 0.20 + , happstack-server >= 0.3 && < 0.4 + , happstack-data >= 0.3 && < 0.4 + , happstack-ixset >= 0.3 && < 0.4 + , happstack-state >= 0.3 && < 0.4 if flag(base4) Build-Depends: base >=4 && <5, syb diff --git a/src/GetExample.hs b/src/GetExample.hs new file mode 100644 --- /dev/null +++ b/src/GetExample.hs @@ -0,0 +1,83 @@ +{-# OPTIONS_GHC -F -pgmFtrhsx #-} + +import Happstack.Server +import HSP +import Happstack.Server.HSP.HTML +import Data.Monoid + +{- We define a very simple data type here to use as our + instance for FromData -} +data Foo = Foo {bar :: Int, + baz :: Int} + deriving Show + +{- Defining an instance of FromData is fundamentally simple. Primarily, you should use the helper function look +to grab the string associated with the named parameter you provide. From there, we use read to parse the string into an +int and return the final Foo. This isn't the safest construction, because the read could fail, but you can easily provide +yourself with more safety by using the MonadPlus instance of RqData and just calling mzero when an error occurs.-} +instance FromData Foo where + fromData = do + x <- read `fmap` look "bar" + y <- read `fmap` look "baz" + return $ Foo x y + +main :: IO () +main = simpleHTTP nullConf{port=8080} $ (dir "getHandler" handler) `mappend` (dir "postHandler" handler) `mappend` home + +{- Please note that we actually use the same handler for both GET & POST requests. + This is an advantage of using FromData. +-} +handler :: ServerPartT IO Response +handler = do + mfoo <- getData + case mfoo of + Nothing -> webHSP $ didn'twork + Just foo -> webHSP $ displayFoo foo + +displayFoo :: Foo -> HSP XML +displayFoo f = + + This is a Foo + + +

Here, look at a Foo: <%show f%>

+

home

+ + + +didn'twork = + + Something is wrong! + + +

Something has gone horribly wrong + go home

+ + + +home :: ServerPartT IO Response +home = webHSP $ + + Get and Post examples + + +
+

+ +
+ +
+ +

+
+
+

+ +
+ +
+ +

+
+ + diff --git a/src/HSPExample.hs b/src/HSPExample.hs new file mode 100644 --- /dev/null +++ b/src/HSPExample.hs @@ -0,0 +1,31 @@ +{-# OPTIONS_GHC -F -pgmFtrhsx #-} +-- You might be wondering what's the point of this options declaration. +-- It enables a particular preprocessor that allows the literal HTML syntax +-- for HSP. Without it this example cannot compile. + +import Happstack.Server +import Happstack.Server.HSP.HTML +import HSP +import System.Random + +main :: IO () +main = simpleHTTP nullConf{port=8080} home + +{- Integrating HSP into Happstack is very simple. One just lifts the HSP value into a ServerPartT with webHSP from + Happstack.Server.HSP.HTML -} +home :: ServerPartT IO Response +home = webHSP $ + + Simple HSP w/ Happstack Example + + +

HSP can be convenient

+
    +
  1. You can include your html in your Haskell file exactly as you'd expect.
    2. +
  2. You can include <%"haskell values"%> very easily in your code.
    3. +
  3. Or even IO actions: <%aux%>.
    4. +
  4. Your HTML is parsed and built at compile time, so that is where mistakes are caught
    5. +
+ + + where aux = doIO $ show `fmap` randomRIO (0,100 :: Int) diff --git a/templates/formsanddata.st b/templates/formsanddata.st new file mode 100644 --- /dev/null +++ b/templates/formsanddata.st @@ -0,0 +1,23 @@ +

GET, POST, and FromData

+

We've covered how to serve basic HTML with Happstack, in a number of different ways. What we haven't yet covered +is what to do with form data. In principle, you could dig into the request and try to pull out the parameters. That's +not the Happstack way, though.

+

Instead, you can use the type class FromData and the functions getData and withData. +A simple example can be found in GetExample.hs. This example uses HSP to build +the forms, for simple convenience.

+

ghci>:i FromData +
class FromData a where fromData :: RqData a +
-- Defined in Happstack.Server.SimpleHTTP +
instance [overlap ok] (FromData a, FromData b) => FromData (a, b) +
-- Defined in Happstack.Server.SimpleHTTP +
instance [overlap ok] (FromData a, FromData b, FromData c) => FromData (a, b, c) +
-- Defined in Happstack.Server.SimpleHTTP +
instance [overlap ok] (FromData a,FromData b,FromData c,FromData d) => FromData (a, b, c, d) +
-- Defined in Happstack.Server.SimpleHTTP +
instance [overlap ok] (FromData a) => FromData (Maybe a) +
-- Defined in Happstack.Server.SimpleHTTP +

+

An important note about RqData is that it is a Monad and a MonadPlus, so between this type class machinery and +the helper function look, you should be able to define your own instances of FromData for your own types. +Again, the simple example up above should provide some guidance for this.

+

Next we cover uploading files

diff --git a/templates/getandpost.st b/templates/getandpost.st --- a/templates/getandpost.st +++ b/templates/getandpost.st @@ -2,18 +2,18 @@

GET data is data attached to an http request via the url string. In the job board app, an example of this is tphyahoo's profile, where the user is specified on the url string. - Another example is fetching a particular job. + Another example is fetching a particular job.

POST data is data attached to a request after submitting a form. One place this is used is in the registration process. - Once you have a user created, you can also see POST in action by editing your profile or creating jobs. + Once you have a user created, you can also see POST in action by editing your profile or creating jobs.

-

Happstack deals with GET and POST data similarly. +

Happstack deals with GET and POST data similarly.

Let's look at how - tphyahoo's profile gets displayed. + tphyahoo's profile gets displayed.

-

Controller.hs: ... , dir "viewprofile" [ methodSP GET \$ userProfile rglobs ] ... +

Controller.hs: ... , dir "viewprofile" [ methodSP GET \$ userProfile rglobs ] ...

using dir and methodSP as above is a common pattern. dir pops the head element of the path array ["viewprofile"], resulting in an empty array. methodSP checks that the path array is empty and that diff --git a/templates/whatsnew.st b/templates/whatsnew.st --- a/templates/whatsnew.st +++ b/templates/whatsnew.st @@ -1,7 +1,4 @@ -

What's new in version 0.8.1

+

What's new in version 0.9.0