The taggy-lens package

[Tags:bsd3, library, test]

Lenses, folds, traversals and prisms for taggy.

This greatly simplifies your life when dealing with the ugly world of Real Life HTML. Here's an example. It lists the date, author and package name of all the recent package uploads entries from the hackage page of the same name. Note that it uses wreq to fetch the Hackage page.

 module Main (main) where

 import Control.Lens (to, only,(^?),ix, toListOf)
 import Data.ByteString.Lazy (ByteString)
 import Data.Text (Text)
 import Data.Text.Encoding.Error (lenientDecode)
 import Data.Text.Lazy.Encoding (decodeUtf8With)
 import Network.HTTP.Client (Response)
 import Network.Wreq (responseBody, get)
 import Text.Taggy (Node)
 import Text.Taggy.Lens (html, elements, children, contents,allNamed)

 data Upload =
   Upload Text -- ^ date
          Text -- ^ author
          Text -- ^ package name
   deriving (Show)

 table :: [Node] -> Maybe Upload
 table row = do
   date    <- row ^? ix 0 . contents
   author  <- row ^? ix 1 . contents
   package <- row ^? ix 2 . elements . contents
   return $ Upload date author package

 recentPackages :: Response ByteString -> [Maybe Upload]
 recentPackages = toListOf
                $ responseBody . to (decodeUtf8With lenientDecode)
                . html . allNamed (only "tr") . children . to table

 main :: IO ()
 main = get "" >>= print `fmap` recentPackages

Report any problem on our issues page on github.


Versions 0.1, 0.1.1, 0.1.2
Dependencies base (>=4.5 && <5), lens (>=4), taggy (>=0.1), text, unordered-containers [details]
License BSD3
Copyright 2014 Alp Mestanogullari, Vikram Verma
Author Alp Mestanogullari, Vikram Verma
Category Text, Web
Home page
Uploaded Tue Jul 15 17:15:55 UTC 2014 by AlpMestanogullari
Distributions LTSHaskell:0.1.2, NixOS:0.1.2, Tumbleweed:0.1.2
Downloads 886 total (12 in the last 30 days)
0 []
Status Docs available [build log]
Successful builds reported [all 1 reports]




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