using haskelldb with chrisdone's template haskell lib

Main.hs

module Main where

import qualified Model.BookField as F
import qualified Model.BookTable as T

import           Database.HaskellDB
import           Database.HaskellDB.HDBRec
import           Database.HaskellDB.Extra

import           Database.HaskellDB.HDBC
import           Database.HaskellDB.Sql.PostgreSQL
import           Database.HaskellDB.PostgreSQL
import           Database.HDBC.PostgreSQL          (connectPostgreSQL)

import           Data.Pagination
import           Data.Default

import System.IO
import Control.Exception

getPassword :: IO String
getPassword = do
    putStr "Password: "
    hFlush stdout
    pass <- withEcho False getLine
    putChar '\n'
    return pass
                    
withEcho :: Bool -> IO a -> IO a
withEcho echo action = do
    old <- hGetEcho stdin
    bracket_ (hSetEcho stdin echo) (hSetEcho stdin old) action


simpleSelection = do
  table T.books

simpleInsert conn = do 
  insert conn 
         T.books 
         ( F.id << val 1
         # F.title << val "hello world")


withDB opts = hdbcConnect generator (connectPostgreSQL conninfo)
  where conninfo = unwords [ k ++ "=" ++ v | (k,v) <- opts]

opts username password dbname = 
  [("host","localhost")
  ,("user",username)
  ,("password",password)
  ,("dbname",dbname)]

main = do
  username <- putStr "username : " >> hFlush stdout >> getLine
  password <- getPassword
  dbname <- putStr "dbname : " >> hFlush stdout >> getLine
  
  r <- withDB (opts username password dbname) 
              (\db-> -- simpleInsert db)
                      query db simpleSelection)
              
  print $ r 
  

Model.BookField.hs

{-# LANGUAGE TemplateHaskell #-}

-- | All database fields.

module Model.BookField where

import Database.HaskellDB.PostgreSQL
import Database.HaskellDB.TH

field "Id" "id" "id" [t|Int|]
field "Title" "title" "title" [t|String|]

Model.BookTable.hs

{-# LANGUAGE TemplateHaskell #-}

-- | Database tables and entities.

module Model.BookTable where

import Model.BookField as Field

import Database.HaskellDB.TH
import Prelude ()

-- | Content table.
table "books" "books"
  ['id
  ,'title
  ]