app: Main: Add a running example of the DSL

Signed-off-by: Sanchayan Maity <maitysanchayan@gmail.com>

app/Main.hs

@@ -1,6 +1,21 @@
+{-# LANGUAGE OverloadedStrings #-}
+
 module Main where
 
+import Database.PostgreSQL.Simple
+import Data.Text (pack)
 import Lib
 
+dslOperations :: Connection -> DSL ()
+dslOperations conn = do
+  logMsg "Logging from inside the DSL"
+  xs <- runQuery conn "select 2 + 2"
+  logMsg $ pack $ show (xs :: [Only Int])
+
 main :: IO ()
-main = putStrLn "Free monad example"
+main = do
+  putStrLn "Free monad example"
+  conn <- connect defaultConnectInfo {
+    connectDatabase = "postgres"
+  }
+  runDSL $ dslOperations conn