implemented high-level logic for strFromConn

src/Network/Gemini/Capsule/Internal.hs

@@ -34,10 +34,16 @@ time.
 
 module Network.Gemini.Capsule.Internal (
   readURL,
-  sendResponse
+  sendResponse,
+  strFromConn,
+  readMax,
+  stripCRLF
 ) where
 
+import qualified Data.ByteString as BS
 import Data.Connection (Connection)
+import qualified Data.Text as T
+import Data.Text.Encoding (decodeUtf8')
 
 import Network.Gemini.Capsule.Encoding
 import Network.Gemini.Capsule.Types
@@ -76,6 +82,28 @@ strFromConn
   -> Connection a
   -- ^ The connection to read from
   -> IO (Maybe String)
-strFromConn = undefined
+strFromConn maxLen conn = do
+  mbs <- readMax maxLen conn
+  return $ do
+    bs  <- mbs
+    txt <- case decodeUtf8' bs of
+      Left _  -> Nothing
+      Right s -> Just s
+    stripCRLF $ T.unpack txt
+
+-- | Reads from a connection up to a maximum number of bytes,
+-- returning 'Nothing' if the limit is exceeded
+readMax
+  :: Int
+  -- ^ the maximum number of bytes
+  -> Connection a
+  -- ^ the 'Connection' to read from
+  -> IO (Maybe BS.ByteString)
+readMax = undefined
+
+-- | Strips the CR/LF characters from the end of a string, retuning
+-- Nothing if they are not present
+stripCRLF :: String -> Maybe String
+stripCRLF = undefined
 
 --jl

test/Network/Gemini/Capsule/InternalSpec.hs

@@ -38,6 +38,8 @@ spec = describe "Internal" $ do
   readURLSpec
   sendResponseSpec
   strFromConnSpec
+  readMaxSpec
+  stripCRLFSpec
 
 readURLSpec :: Spec
 readURLSpec = describe "readURL" $ mapM_
@@ -56,10 +58,10 @@ readURLSpec = describe "readURL" $ mapM_
   ]
 
   where
-    validConn   = mkConn "gemini://example.com/\r\n"
-    longConn    = mkConn longBS
-    tooLongConn = mkConn tooLongBS
-    gibConn     = mkConn "aosidjfwoeinboijwefr"
+    validConn   = mkInConn ["gemini://example.com/\r\n"]
+    longConn    = mkInConn [longBS]
+    tooLongConn = mkInConn [tooLongBS]
+    gibConn     = mkInConn ["aosidjfwoeinboijwefr"]
     longBS      = BS.pack (take 1024 bytes) <> "\r\n"
     tooLongBS   = BS.pack (take 1025 bytes) <> "\r\n"
     bytes       = BS.unpack prefix ++ repeat (fromIntegral $ ord 'A')
@@ -67,14 +69,32 @@ readURLSpec = describe "readURL" $ mapM_
     longExp     = validExp { gemPath = [longDir] }
     longDir     = replicate (1024 - BS.length prefix) 'A'
     prefix      = "gemini://example.com/"
-    mkConn bs   = do
-      s <- nullInput
-      unRead bs s
-      return sampleConnection { source = s }
 
 sendResponseSpec :: Spec
 sendResponseSpec = describe "sendResponse" $ return ()
 
+strFromConnSpec :: Spec
+strFromConnSpec = describe "strFromConn" $ mapM_
+  ( \(desc, maxLen, ioConn, expect) -> context desc $
+    xit ("should return " ++ show expect) $ do
+      conn <- ioConn
+      strFromConn maxLen conn `shouldReturn` expect
+  )
+
+  --  description,    max size, connection,                expected
+  [ ( "valid string", 100,      mkInConn ["foo\r\n"],      Just "foo"  )
+  , ( "long string",  5,        mkInConn ["too long\r\n"], Nothing     )
+  , ( "no CR/LF",     100,      mkInConn ["foo"],          Nothing     )
+  , ( "bad UTF-8",    100,      mkInConn ["foo\xff\r\n"],  Nothing     )
+  , ( "non-ASCII",    100,      mkInConn ["\xc3\xa9\r\n"], Just "\xe9" )
+  ]
+
+mkInConn :: [BS.ByteString] -> IO (Connection a)
+mkInConn bss = do
+  s <- nullInput
+  mapM_ (`unRead` s) (reverse bss)
+  return sampleConnection { source = s }
+
 sampleConnection :: Connection a
 sampleConnection = Connection
   { source        = undefined
@@ -83,7 +103,10 @@ sampleConnection = Connection
   , connExtraInfo = undefined
   }
 
-strFromConnSpec :: Spec
-strFromConnSpec = describe "strFromConn" $ return ()
+readMaxSpec :: Spec
+readMaxSpec = describe "readMax" $ return ()
+
+stripCRLFSpec :: Spec
+stripCRLFSpec = describe "stripCRLF" $ return ()
 
 --jl