{-# options_haddock prune #-}

-- |Description: Streaming Implementation, Internal
module Polysemy.Http.Http where

import qualified Data.ByteString as ByteString

import Polysemy.Http.Data.HttpError (HttpError)
import Polysemy.Http.Data.Request (Request)
import Polysemy.Http.Data.Response (Response (Response))
import Polysemy.Http.Data.StreamChunk (StreamChunk (StreamChunk))
import qualified Polysemy.Http.Data.StreamEvent as StreamEvent
import Polysemy.Http.Data.StreamEvent (StreamEvent)
import qualified Polysemy.Http.Effect.Http as Http
import Polysemy.Http.Effect.Http (Http)

streamLoop ::
  Members [Http c, Error HttpError] r =>
  Maybe Int ->
  (∀ x . StreamEvent o c h x -> Sem r x) ->
  Response c ->
  h ->
  Sem r o
streamLoop :: forall c (r :: EffectRow) o h.
Members '[Http c, Error HttpError] r =>
Maybe Int
-> (forall x. StreamEvent o c h x -> Sem r x)
-> Response c
-> h
-> Sem r o
streamLoop Maybe Int
chunkSize forall x. StreamEvent o c h x -> Sem r x
process response :: Response c
response@(Response Status
_ c
body [Header]
_ CookieJar
_) h
handle =
  Sem r o
spin
  where
    spin :: Sem r o
spin =
      ByteString -> Sem r o
handleChunk (ByteString -> Sem r o) -> Sem r ByteString -> Sem r o
forall (m :: * -> *) a b. Monad m => (a -> m b) -> m a -> m b
=<< Either HttpError ByteString -> Sem r ByteString
forall e (r :: EffectRow) a.
Member (Error e) r =>
Either e a -> Sem r a
fromEither (Either HttpError ByteString -> Sem r ByteString)
-> Sem r (Either HttpError ByteString) -> Sem r ByteString
forall (m :: * -> *) a b. Monad m => (a -> m b) -> m a -> m b
=<< Maybe Int -> c -> Sem r (Either HttpError ByteString)
forall c (r :: EffectRow).
Member (Http c) r =>
Maybe Int -> c -> Sem r (Either HttpError ByteString)
Http.consumeChunk Maybe Int
chunkSize c
body
    handleChunk :: ByteString -> Sem r o
handleChunk (ByteString -> Bool
ByteString.null -> Bool
True) =
      StreamEvent o c h o -> Sem r o
forall x. StreamEvent o c h x -> Sem r x
process (Response c -> h -> StreamEvent o c h o
forall c h r. Response c -> h -> StreamEvent r c h r
StreamEvent.Result Response c
response h
handle)
    handleChunk !ByteString
chunk = do
      StreamEvent o c h () -> Sem r ()
forall x. StreamEvent o c h x -> Sem r x
process (h -> StreamChunk -> StreamEvent o c h ()
forall h r c. h -> StreamChunk -> StreamEvent r c h ()
StreamEvent.Chunk h
handle (ByteString -> StreamChunk
StreamChunk ByteString
chunk))
      Sem r o
spin

streamHandler ::
  ∀ o r c h .
  Members [Http c, Error HttpError, Resource] r =>
  Maybe Int ->
  (∀ x . StreamEvent o c h x -> Sem r x) ->
  Response c ->
  Sem r o
streamHandler :: forall o (r :: EffectRow) c h.
Members '[Http c, Error HttpError, Resource] r =>
Maybe Int
-> (forall x. StreamEvent o c h x -> Sem r x)
-> Response c
-> Sem r o
streamHandler Maybe Int
chunkSize forall x. StreamEvent o c h x -> Sem r x
process Response c
response = do
  Sem r h -> (h -> Sem r ()) -> (h -> Sem r o) -> Sem r o
forall (r :: EffectRow) a c b.
Member Resource r =>
Sem r a -> (a -> Sem r c) -> (a -> Sem r b) -> Sem r b
bracket Sem r h
acquire h -> Sem r ()
release (Maybe Int
-> (forall x. StreamEvent o c h x -> Sem r x)
-> Response c
-> h
-> Sem r o
forall c (r :: EffectRow) o h.
Members '[Http c, Error HttpError] r =>
Maybe Int
-> (forall x. StreamEvent o c h x -> Sem r x)
-> Response c
-> h
-> Sem r o
streamLoop Maybe Int
chunkSize forall x. StreamEvent o c h x -> Sem r x
process Response c
response)
  where
    acquire :: Sem r h
acquire =
      StreamEvent o c h h -> Sem r h
forall x. StreamEvent o c h x -> Sem r x
process (Response c -> StreamEvent o c h h
forall c r h. Response c -> StreamEvent r c h h
StreamEvent.Acquire Response c
response)
    release :: h -> Sem r ()
release h
handle =
      StreamEvent o c h () -> Sem r ()
forall x. StreamEvent o c h x -> Sem r x
process (h -> StreamEvent o c h ()
forall h r c. h -> StreamEvent r c h ()
StreamEvent.Release h
handle)

-- |Initiate a request and stream the response, calling @process@ after connecting, for every chunk, after closing the
-- connection, and for the return value.
-- 'StreamEvent' is used to indicate the stage of the request cycle.
-- The optional 'Int' argument defines the minimal chunk size that is read for each callback. If it is 'Nothing', the
-- stream reads what is available.
--
-- @
-- handle ::
--   StreamEvent Double (IO ByteString) Int a ->
--   Sem r a
-- handle = \\case
--   StreamEvent.Acquire (Response status body headers) ->
--     pure 1
--   StreamEvent.Chunk handle (StreamChunk c) ->
--     pure ()
--   StreamEvent.Result (Response status body headers) handle ->
--     pure 5.5
--   StreamEvent.Release handle ->
--     pure ()
-- @
-- >>> runInterpreters $ streamResponse (Http.get "host.com" "path/to/file") handle
-- 5.5
streamResponse ::
  Members [Http c, Error HttpError, Resource] r =>
  Request ->
  Maybe Int ->
  (∀ x . StreamEvent o c h x -> Sem r x) ->
  Sem r o
streamResponse :: forall c (r :: EffectRow) o h.
Members '[Http c, Error HttpError, Resource] r =>
Request
-> Maybe Int
-> (forall x. StreamEvent o c h x -> Sem r x)
-> Sem r o
streamResponse Request
request Maybe Int
chunkSize forall x. StreamEvent o c h x -> Sem r x
process =
  Either HttpError o -> Sem r o
forall e (r :: EffectRow) a.
Member (Error e) r =>
Either e a -> Sem r a
fromEither (Either HttpError o -> Sem r o)
-> (Either HttpError (Either HttpError o) -> Either HttpError o)
-> Either HttpError (Either HttpError o)
-> Sem r o
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Either HttpError (Either HttpError o) -> Either HttpError o
forall (m :: * -> *) a. Monad m => m (m a) -> m a
join (Either HttpError (Either HttpError o) -> Sem r o)
-> Sem r (Either HttpError (Either HttpError o)) -> Sem r o
forall (m :: * -> *) a b. Monad m => (a -> m b) -> m a -> m b
=<< Request
-> (Response c -> Sem r (Either HttpError o))
-> Sem r (Either HttpError (Either HttpError o))
forall c (r :: EffectRow) a.
Member (Http c) r =>
Request -> (Response c -> Sem r a) -> Sem r (Either HttpError a)
Http.response Request
request (Sem (Error HttpError : r) o -> Sem r (Either HttpError o)
forall e (r :: EffectRow) a.
Sem (Error e : r) a -> Sem r (Either e a)
runError (Sem (Error HttpError : r) o -> Sem r (Either HttpError o))
-> (Response c -> Sem (Error HttpError : r) o)
-> Response c
-> Sem r (Either HttpError o)
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Maybe Int
-> (forall x. StreamEvent o c h x -> Sem (Error HttpError : r) x)
-> Response c
-> Sem (Error HttpError : r) o
forall o (r :: EffectRow) c h.
Members '[Http c, Error HttpError, Resource] r =>
Maybe Int
-> (forall x. StreamEvent o c h x -> Sem r x)
-> Response c
-> Sem r o
streamHandler Maybe Int
chunkSize (Sem r x -> Sem (Error HttpError : r) x
forall (e :: (* -> *) -> * -> *) (r :: EffectRow) a.
Sem r a -> Sem (e : r) a
raise (Sem r x -> Sem (Error HttpError : r) x)
-> (StreamEvent o c h x -> Sem r x)
-> StreamEvent o c h x
-> Sem (Error HttpError : r) x
forall b c a. (b -> c) -> (a -> b) -> a -> c
. StreamEvent o c h x -> Sem r x
forall x. StreamEvent o c h x -> Sem r x
process))