How can I execute a GET with Haskell's Network.HTTP.Req library?

Question

I am trying to execute a simple HTTP GET request but I get back a 404. I assume there is an issue on the URL but I can't find it.

Here is the function that executes the request:

getMockResource :: (MonadHttp m) =>  m BsResponse 
getMockResource = req
  GET
  (http "www.mocky.io" /: "/v2/5da208d92f00007900f418ff")
  NoReqBody
  bsResponse
  mempty

my main:

main :: IO ()
main = runReq defaultHttpConfig $ do
  r <- getMockResource
  liftIO $ B.putStrLn (responseBody r)

and here is the output:

VanillaHttpException (HttpExceptionRequest Request {
  host                 = "www.mocky.io"
  port                 = 80
  secure               = False
  requestHeaders       = []
  path                 = "/%2Fv2%2F5da208d92f00007900f418ff"
  queryString          = ""
  method               = "GET"
  proxy                = Nothing
  rawBody              = False
  redirectCount        = 10
  responseTimeout      = ResponseTimeoutDefault
  requestVersion       = HTTP/1.1
}
 (StatusCodeException (Response {responseStatus = Status {statusCode = 404, statusMessage = "Not Found"}, responseVersion = HTTP/1.1, responseHeaders = [("Server","Cowboy"),("Connection","keep-alive
"),("Date","Sat, 12 Oct 2019 21:09:09 GMT"),("Content-Type","text/html; charset=UTF-8"),("Content-Length","2137"),("Via","1.1 vegur")], responseBody = (), responseCookieJar = CJ {expose = []}, respo
nseClose' = ResponseClose}) "



    
        Not Found



The resource is avaliable at http://www.mocky.io/v2/5da208d92f00007900f418ff

Any ideas of where the problem lies? Thank you!

user_67579 · Answer

The path is escaped here. In order to use a slash, you can make use of the (/~) :: ToHttpApiData a => Url scheme -> a -> Url scheme function:

getMockResource :: MonadHttp m =>  m BsResponse 
getMockResource = req
  GET
  (http "www.mocky.io" /: "v2" /~ "5da208d92f00007900f418ff")
  NoReqBody
  bsResponse
  mempty

user_2352866 · Answer

Thanks to https://stackoverflow.com/users/67579/willem-van-onsem 's hint I took a closer look on the URL creation and I needed

http "www.mocky.io" /: "v2" /: "5da208d92f00007900f418ff"

instead of:

(http "www.mocky.io" /: "/v2/5da208d92f00007900f418ff")

How can I execute a GET with Haskell's Network.HTTP.Req library?

2 Answers