[Haskell-beginners] Download a large file using Network.HTTP

[Cedric Fung]

Wow, thanks to Felipe's and Michael's quick response. Haskell community is
so kind.

I will try your suggestions right now!


On Mon, Dec 10, 2012 at 9:46 PM, Michael Snoyman <michael at snoyman.com>wrote:

> Here's an example of printing the total number of bytes consumed using
> http-conduit:
>
> import           Control.Monad.IO.Class (liftIO)
> import qualified Data.ByteString        as S
> import           Data.Conduit
> import           Data.Conduit.Binary    as CB
> import           Network.HTTP.Conduit
>
> main :: IO ()
> main = withManager $ \manager -> do
>     req <- parseUrl "http://www.yesodweb.com/"
>     res <- http req manager
>     responseBody res $$+- printProgress =$ CB.sinkFile "yesodweb.html"
>
> printProgress :: Conduit S.ByteString (ResourceT IO) S.ByteString
> printProgress =
>     loop 0
>   where
>     loop len = await >>= maybe (return ()) (\bs -> do
>         let len' = len + S.length bs
>         liftIO $ putStrLn $ "Bytes consumed: " ++ show len'
>         yield bs
>         loop len')
>
>
> HTH,
> Michael
>
>
> On Mon, Dec 10, 2012 at 3:34 PM, Cedric Fung <root at vec.io> wrote:
>
>> Hi,
>>
>> Are there any suggestions to download a large file with Haskell? I have
>> read the docs for Network, Network.HTTP and Network.HTTP.Conduit, but can't
>> find anything which fit my requirements.
>>
>> I want to download a large file from an HTTP URL, and show the progress
>> instantly. Maybe some functions which read HTTP connection and return a
>> lazy ByteString could do this work?
>>
>> Though I found a low-level socket lazy package, which seems to work, I
>> just want a more high level API.
>>
>> Thanks and regards.
>>
>> _______________________________________________
>> Beginners mailing list
>> Beginners at haskell.org
>> http://www.haskell.org/mailman/listinfo/beginners
>>
>>
>
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