Alright, after doing some code cleanup I have something that I can run
on Heroku and locally with `yesod --dev devel`.  Any comments or
suggestions are welcome!  I was thinking about making a little self
hosting tutorial and putting the code on github and hosting it on
Heroku.  Is this something that would be helpful or would that be
duplicating additions changes to be made to the Procfile?

Thanks for the help,
Andrew

canonicalizeKey :: (Text, val) -> (Text, val)
canonicalizeKey ("dbname", val) = ("database", val)
canonicalizeKey pair = pair

toMapping :: [(key, val)] -> DO.Object key val
toMapping = DO.Mapping . map (\(key, val) -> (key, DO.Scalar val))

combineMappings :: DO.Object key val -> DO.Object key val -> DO.Object
key val
combineMappings (DO.Mapping m1) (DO.Mapping m2) = DO.Mapping $ m1 ++
m2
combineMappings _ _ = error "Data.Object is not a Mapping."

loadHerokuConfig :: DO.TextObject -> IO Settings.PersistConfig
loadHerokuConfig ymlenv = do
#if DEVELOPMENT
 let urlMap = DO.Mapping []
#else
 urlMap <- Web.Heroku.dbConnParams >>= return . toMapping . map
canonicalizeKey
#endif
 either error return $ Database.Persist.Base.loadConfig
(combineMappings urlMap ymlenv)

-- This function allocates resources (such as a database connection
pool),
-- performs initialization and creates a WAI application. This is also
the
-- place to put your migrate statements to have automatic database
-- migrations handled by Yesod.

withYesodHeroku :: AppConfig DefaultEnv () -> Logger -> (Application -
> IO ()) -> IO ()
withYesodHeroku conf logger f = do
   s <- staticSite

   dbconf <- withYamlEnvironment "config/postgresql.yml" (appEnv

conf) loadHerokuConfig

   Database.Persist.Base.withPool (dbconf :: Settings.PersistConfig)
$ \p -> do
       Database.Persist.Base.runPool dbconf (runMigration migrateAll)
p
       let h = YesodHeroku conf logger s p
       defaultRunner (f . logWare) h
 where
#ifdef DEVELOPMENT
   logWare = logHandleDev (\msg -> logBS logger msg >> flushLogger
logger)
#else
   logWare = logStdout
#endif

On Dec 29, 9:51 pm, Andrew Myers <asm...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> Thanks for bearing with me Greg, I've got something that hosts the
> default hello page on Heroku now.  I'm quite sure it's not at all
> kosher though :p Maybe you can give me some pointers on a sane way to
> do it.
>
> All the code changes were in Application.hs generated by the
> scaffolding.
> Created this function for making keys that the
> `Database.Persist.Base.loadConfig` expects.  There's only one
> different from what `Web.Heroku.dbConnParams` does so it doesn't
> actually do much.
>
> canonicalizeKey :: Text -> Text
> canonicalizeKey "dbname" = "database"
> canonicalizeKey key = key
>
> I then modified withYesodHeroku as follows.
>
> withYesodHeroku :: AppConfig DefaultEnv () -> Logger -> (Application -> IO ()) -> IO ()
>
> withYesodHeroku conf logger f = do
>     s <- staticSite
> -- This line is pretty heinous.  It seems like I should somehow get
> the port and poolsize from the yaml
> -- configs and then combine that with the parameters from
> `Web.Heroku.dbConnParams`
> -- This takes the parameters from the DATABASE_URL and puts them in
> the form that `loadConfig`
> -- expects, adding port and poolsize.
>     dbparams <- Web.Heroku.dbConnParams >>= return . DO.Mapping .
> ([("port", DO.Scalar "5432"), ("poolsize", DO.Scalar "10")] ++) . map
> (\(key, val) -> (canonicalizeKey key, DO.Scalar val))
> -- Create the Database.Persist.PersistConfig with loadConfig of
> dbparams
>     let dbconf = either error id $ Database.Persist.Base.loadConfig
> dbparams
>     -- These two lines are how the original config was loaded.
>     -- dbconf <- withYamlEnvironment "config/postgresql.yml" (appEnv
> conf)
>     --         $ either error return .
> Database.Persist.Base.loadConfig
>     Database.Persist.Base.withPool (dbconf :: Settings.PersistConfig)
> $ \p -> do
>         Database.Persist.Base.runPool dbconf (runMigration migrateAll)
> p
>         let h = YesodHeroku conf logger s p
>         defaultRunner (f . logWare) h
>   where
> #ifdef DEVELOPMENT
>     logWare = logHandleDev (\msg -> logBS logger msg >> flushLogger
> logger)
> #else
>     logWare = logStdout
> #endif
>
> As I said, it's pretty grotesque :p, but it at least allows me to see
> a webpage on my heroku site.  I'm going to look at withYamlEnvironment
> and see if I can combine the parameters from the database variable and
> the yaml configs.  Do you have any suggestions?  Am I at least on the
> right track or am I doing something crazy?
>
> Thanks again,
> Andrew
>
> On Dec 29, 8:05 pm, Greg Weber <g...-6Rig8Yl2aw4Die4ONvY22w@public.gmane.org> wrote:
>
>
>
>
>
>
>
> > On Thu, Dec 29, 2011 at 3:02 PM, Andrew Myers <asm...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> > > Some pointers on the postgre setup might be helpful if you don't
> > > mind.  Not knowing anything about Yesod beyond what I've read in the
> > > book I don't really understand the instructions in the Procfile.
>
> > > From the instructions (pasted below) I have the following questions:
>
> > > - Why do I have to parse the DATABASE_URL variable in main?
>
> > You need to parse it and then used it to make the database connection.
>
> > I can't find any references to 'withConnectionPool' or 'loadConnStr' except
>
> > > inside Yesod itself.  In the Scaffold generated Settings.hs there's a
> > > reference to Database.Persist.Base.withPool inside 'withYesodHeroku',
> > > is this what I want to pass arguments to?  Right now they're read from
> > > the "config/postgresql.yml" file which of course is wrong when
> > > deployed to heroku with a free shared db.
>
> > > - Where does the `dbConnParams _ = Web.Heroku.dbConnParams` bit of
> > > code from the ProcFile fit?  I can't find any references to it
> > > anywhere so adding that code to Settings.hs doesn't do anything.
> > > Web.Heroku.dbConnParams parses the DATABASE_URL variable itself, how
> > > does this relate to the parsing that's supposed to be done in main?
>
> > > - Looking at The Database.Persist.Postgresql [1] package docs it looks
> > > like a PersistConf is just a url and a pool size for PostGres, should
> > > I just create one of these in `withYesodHeroku?
>
> > Oh, the Procfile instructions are now out of date with the new scaffolding
> > changes. We need to override how Yesod connects to the database so that it
> > uses the parsed DATABASE_URL. I am busy at the moment, but will get back to
> > you soon.
>
> > > Thanks again for the help Greg!
>
> > > [1]
> > >http://hackage.haskell.org/packages/archive/persistent-postgresql/0.6...
>
> > > # Postgresql Yesod setup:
> > > #
> > > # * add code to read DATABASE_URL environment variable.
> > > #
> > > #   import System.Environment
> > > #   main = do
> > > #     durl <- getEnv "DATABASE_URL"
> > > #     # parse env variable
> > > #     # pass settings to withConnectionPool instead of directly using
> > > loadConnStr
> > > #
> > > # * add a dependency on the "heroku" package in your cabal file
> > > #
> > > # * add code in Settings.hs to turn that url into connection
> > > parameters. The below works for Postgresql.
> > > #
> > > #     #ifdef !DEVELOPMENT
> > > #     import qualified Web.Heroku
> > > #     #endif
> > > #
> > > #     dbConnParams :: AppEnvironment -> IO [(Text, Text)]
> > > #     #ifdef !DEVELOPMENT
> > > #     dbConnParams _ = Web.Heroku.dbConnParams
> > > #     #else
> > > #     dbConnParams env = do
> > > #       ...
>
> > > On Dec 29, 11:58 am, Greg Weber <g...-6Rig8Yl2aw4Die4ONvY22w@public.gmane.org> wrote:
> > > > yes that looks correct. I just modified the scaffolding Procfile to
> > > include
> > > > the environment argument. There is detailed information in the Procfile
> > > for
> > > > setting up the heroku port. Let us know if anything else needs to be
> > > > changed.
>
> > > > On Thu, Dec 29, 2011 at 1:25 PM, Andrew Myers <asm...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> > > > > I see, I now have
> > > > > web: ./dist/build/yesod-heroku/yesod-heroku -p $PORT production
> > > > > in my Procfile.  This seems to work (in as much as the application now
> > > > > starts, need to point it at the right postgres db now) is this the
> > > > > correct way to do this?
> > > > > Thanks Greg
>
> > > > > On Dec 29, 11:01 am, Greg Weber <g...-6Rig8Yl2aw4Die4ONvY22w@public.gmane.org> wrote:
> > > > > > yesod devel is somewhat magical. You should be able to compile your
> > > > > > application and run it without it though. It is `cabal install
> > > -fdev`.
> > > > > Then
> > > > > > run the binary created in the dist folder and give an environment
> > > > > argument
> > > > > > of "development". for production compile with no flags and give an
> > > > > > environment argument of "production". This definitely needs to be
> > > > > > incorporated into the book now.
>
> > > > > > On Thu, Dec 29, 2011 at 12:43 PM, Andrew Myers <asm...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> > > wrote:
> > > > > > > Sorry if I'm being dense but could you clarify that or point me to
> > > > > > > some documentation?  I've been looking for documentation on that
> > > and
> > > > > > > trying to figure out how `yesod devel` starts the application but
> > > it
> > > > > > > hasn't been very fruitful so far.
> > > > > > > Thanks,
> > > > > > > Andrew
>
> > > > > > > On Dec 28, 6:23 pm, Greg Weber <g...-6Rig8Yl2aw4Die4ONvY22w@public.gmane.org> wrote:
> > > > > > > > Glad SO could help you out. We now require an environment
> > > argument
> > > > > for
> > > > > > > the
> > > > > > > > executable. I think the poor error message is a limitation of
> > > > > cmdargs.
>
> > > > > > > > On Wed, Dec 28, 2011 at 8:04 PM, Andrew Myers <asm...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> > > > > wrote:
> > > > > > > > > Thanks Greg,
>
> > > > > > > > > I posted on SO as suggested and someone helped me out.
> > > > > > > > > Turned out the problem was that by libc is newer than the libc
> > > on
> > > > > > > > > Heroku hosts (Archlinux is a rolling release distro).  I
> > > solved the
> > > > > > > > > problem
> > > > > > > > > by creating an ubuntu virtual machine and building/deploying
> > > from
> > > > > > > > > there.
>
> > > > > > > > > The relevant answer is herehttp://
> > > > > stackoverflow.com/a/8658468/166732
>
> > > > > > > > > Now I'm getting an error from the application processing
> > > arguments,
> > > > > > > > > not sure what it means or why yet.
>
> > > > > > > > > 2011-12-28T22:51:49+00:00 heroku[web.1]: Starting process with
> > > > > command
> > > > > > > > > `./dist/build/yesod-heroku/yesod-heroku -p 23748`
> > > > > > > > > 2011-12-28T22:51:49+00:00 app[web.1]: Requires at least 1
> > > > > arguments,
> > > > > > > > > got 0
>
> > > > > > > > > Has anyone seen that?  I haven't figured out what code I'm
> > > > > supposed to
> > > > > > > > > modify from
> > > > > > > > > the directions in the Procfile yet.  The indicated changes in
> > > > > > > > > Settings.hs don't seem
> > > > > > > > > to be relevant to what's actually there and I'm not sure what
> > > file
> > > > > the
> > > > > > > > > other code
> > > > > > > > > block is referencing.  It could be that though.
>
> > > > > > > > > Thanks,
> > > > > > > > > Andrew
>
> > > > > > > > > On Dec 28, 6:11 am, Greg Weber <g...-6Rig8Yl2aw4Die4ONvY22w@public.gmane.org> wrote:
> > > > > > > > > > Hi Andrew,
>
> > > > > > > > > > For my deployment I used a very simple application, and
> > > building
> > > > > with
> > > > > > > > > > -static just worked for me. I have definitely heard that it
> > > > > tends to
> > > > > > > be
> > > > > > > > > > much harder. I think you will be better off engaging the
> > > wider
> > > > > > > Haskell
> > > > > > > > > > community more experienced with static builds, perhaps by
> > > posting
> > > > > > > your
> > > > > > > > > > question to StackOverflow. Let us know how it turns out - we
> > > > > should
> > > > > > > be
> > > > > > > > > able
> > > > > > > > > > to point people to documentation on how to perform a static
> > > > > build.
>
> > > > > > > > > > Greg Weber
>
> > > > > > > > > > On Tue, Dec 27, 2011 at 11:21 PM, Andrew Myers <
> > > asm...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org
>
> > > > > > > wrote:
> > > > > > > > > > > I'm very new to Yesod and I'm having trouble building Yesod
> > > > > > > statically
> > > > > > > > > > > so I can deploy to Heroku.
>
> > > > > > > > > > > I have changed the default .cabal file to reflect static
>

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