{-# LANGUAGE DeriveDataTypeable #-}
{-# LANGUAGE DeriveGeneric      #-}
{-# LANGUAGE OverloadedStrings  #-}
{-# LANGUAGE RecordWildCards    #-}
{-# LANGUAGE TypeFamilies       #-}

{-# OPTIONS_GHC -fno-warn-unused-imports #-}
{-# OPTIONS_GHC -fno-warn-unused-binds   #-}
{-# OPTIONS_GHC -fno-warn-unused-matches #-}

-- Derived from AWS service descriptions, licensed under Apache 2.0.

-- |
-- Module      : Network.AWS.DMS.DescribeSchemas
-- Copyright   : (c) 2013-2018 Brendan Hay
-- License     : Mozilla Public License, v. 2.0.
-- Maintainer  : Brendan Hay <brendan.g.hay+amazonka@gmail.com>
-- Stability   : auto-generated
-- Portability : non-portable (GHC extensions)
--
-- Returns information about the schema for the specified endpoint.
--
--
--
--
--
-- This operation returns paginated results.
module Network.AWS.DMS.DescribeSchemas
    (
    -- * Creating a Request
      describeSchemas
    , DescribeSchemas
    -- * Request Lenses
    , dsMarker
    , dsMaxRecords
    , dsEndpointARN

    -- * Destructuring the Response
    , describeSchemasResponse
    , DescribeSchemasResponse
    -- * Response Lenses
    , dsrsSchemas
    , dsrsMarker
    , dsrsResponseStatus
    ) where

import Network.AWS.DMS.Types
import Network.AWS.DMS.Types.Product
import Network.AWS.Lens
import Network.AWS.Pager
import Network.AWS.Prelude
import Network.AWS.Request
import Network.AWS.Response

-- |
--
--
--
-- /See:/ 'describeSchemas' smart constructor.
data DescribeSchemas = DescribeSchemas'
  { _dsMarker      :: !(Maybe Text)
  , _dsMaxRecords  :: !(Maybe Int)
  , _dsEndpointARN :: !Text
  } deriving (Eq, Read, Show, Data, Typeable, Generic)


-- | Creates a value of 'DescribeSchemas' with the minimum fields required to make a request.
--
-- Use one of the following lenses to modify other fields as desired:
--
-- * 'dsMarker' - An optional pagination token provided by a previous request. If this parameter is specified, the response includes only records beyond the marker, up to the value specified by @MaxRecords@ .
--
-- * 'dsMaxRecords' - The maximum number of records to include in the response. If more records exist than the specified @MaxRecords@ value, a pagination token called a marker is included in the response so that the remaining results can be retrieved.  Default: 100 Constraints: Minimum 20, maximum 100.
--
-- * 'dsEndpointARN' - The Amazon Resource Name (ARN) string that uniquely identifies the endpoint.
describeSchemas
    :: Text -- ^ 'dsEndpointARN'
    -> DescribeSchemas
describeSchemas pEndpointARN_ =
  DescribeSchemas'
    { _dsMarker = Nothing
    , _dsMaxRecords = Nothing
    , _dsEndpointARN = pEndpointARN_
    }


-- | An optional pagination token provided by a previous request. If this parameter is specified, the response includes only records beyond the marker, up to the value specified by @MaxRecords@ .
dsMarker :: Lens' DescribeSchemas (Maybe Text)
dsMarker = lens _dsMarker (\ s a -> s{_dsMarker = a})

-- | The maximum number of records to include in the response. If more records exist than the specified @MaxRecords@ value, a pagination token called a marker is included in the response so that the remaining results can be retrieved.  Default: 100 Constraints: Minimum 20, maximum 100.
dsMaxRecords :: Lens' DescribeSchemas (Maybe Int)
dsMaxRecords = lens _dsMaxRecords (\ s a -> s{_dsMaxRecords = a})

-- | The Amazon Resource Name (ARN) string that uniquely identifies the endpoint.
dsEndpointARN :: Lens' DescribeSchemas Text
dsEndpointARN = lens _dsEndpointARN (\ s a -> s{_dsEndpointARN = a})

instance AWSPager DescribeSchemas where
        page rq rs
          | stop (rs ^. dsrsMarker) = Nothing
          | stop (rs ^. dsrsSchemas) = Nothing
          | otherwise =
            Just $ rq & dsMarker .~ rs ^. dsrsMarker

instance AWSRequest DescribeSchemas where
        type Rs DescribeSchemas = DescribeSchemasResponse
        request = postJSON dms
        response
          = receiveJSON
              (\ s h x ->
                 DescribeSchemasResponse' <$>
                   (x .?> "Schemas" .!@ mempty) <*> (x .?> "Marker") <*>
                     (pure (fromEnum s)))

instance Hashable DescribeSchemas where

instance NFData DescribeSchemas where

instance ToHeaders DescribeSchemas where
        toHeaders
          = const
              (mconcat
                 ["X-Amz-Target" =#
                    ("AmazonDMSv20160101.DescribeSchemas" :: ByteString),
                  "Content-Type" =#
                    ("application/x-amz-json-1.1" :: ByteString)])

instance ToJSON DescribeSchemas where
        toJSON DescribeSchemas'{..}
          = object
              (catMaybes
                 [("Marker" .=) <$> _dsMarker,
                  ("MaxRecords" .=) <$> _dsMaxRecords,
                  Just ("EndpointArn" .= _dsEndpointARN)])

instance ToPath DescribeSchemas where
        toPath = const "/"

instance ToQuery DescribeSchemas where
        toQuery = const mempty

-- |
--
--
--
-- /See:/ 'describeSchemasResponse' smart constructor.
data DescribeSchemasResponse = DescribeSchemasResponse'
  { _dsrsSchemas        :: !(Maybe [Text])
  , _dsrsMarker         :: !(Maybe Text)
  , _dsrsResponseStatus :: !Int
  } deriving (Eq, Read, Show, Data, Typeable, Generic)


-- | Creates a value of 'DescribeSchemasResponse' with the minimum fields required to make a request.
--
-- Use one of the following lenses to modify other fields as desired:
--
-- * 'dsrsSchemas' - The described schema.
--
-- * 'dsrsMarker' - An optional pagination token provided by a previous request. If this parameter is specified, the response includes only records beyond the marker, up to the value specified by @MaxRecords@ .
--
-- * 'dsrsResponseStatus' - -- | The response status code.
describeSchemasResponse
    :: Int -- ^ 'dsrsResponseStatus'
    -> DescribeSchemasResponse
describeSchemasResponse pResponseStatus_ =
  DescribeSchemasResponse'
    { _dsrsSchemas = Nothing
    , _dsrsMarker = Nothing
    , _dsrsResponseStatus = pResponseStatus_
    }


-- | The described schema.
dsrsSchemas :: Lens' DescribeSchemasResponse [Text]
dsrsSchemas = lens _dsrsSchemas (\ s a -> s{_dsrsSchemas = a}) . _Default . _Coerce

-- | An optional pagination token provided by a previous request. If this parameter is specified, the response includes only records beyond the marker, up to the value specified by @MaxRecords@ .
dsrsMarker :: Lens' DescribeSchemasResponse (Maybe Text)
dsrsMarker = lens _dsrsMarker (\ s a -> s{_dsrsMarker = a})

-- | -- | The response status code.
dsrsResponseStatus :: Lens' DescribeSchemasResponse Int
dsrsResponseStatus = lens _dsrsResponseStatus (\ s a -> s{_dsrsResponseStatus = a})

instance NFData DescribeSchemasResponse where