DescribeStacks.hs

{-# LANGUAGE DataKinds                   #-}
{-# LANGUAGE DeriveGeneric               #-}
{-# LANGUAGE FlexibleInstances           #-}
{-# LANGUAGE GeneralizedNewtypeDeriving  #-}
{-# LANGUAGE LambdaCase                  #-}
{-# LANGUAGE NoImplicitPrelude           #-}
{-# LANGUAGE OverloadedStrings           #-}
{-# LANGUAGE RecordWildCards             #-}
{-# LANGUAGE TypeFamilies                #-}

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

-- Module      : Network.AWS.CloudFormation.DescribeStacks
-- Copyright   : (c) 2013-2014 Brendan Hay <brendan.g.hay@gmail.com>
-- License     : This Source Code Form is subject to the terms of
--               the Mozilla Public License, v. 2.0.
--               A copy of the MPL can be found in the LICENSE file or
--               you can obtain it at http://mozilla.org/MPL/2.0/.
-- Maintainer  : Brendan Hay <brendan.g.hay@gmail.com>
-- Stability   : experimental
-- Portability : non-portable (GHC extensions)
--
-- Derived from AWS service descriptions, licensed under Apache 2.0.

-- | Returns the description for the specified stack; if no stack name was
-- specified, then it returns the description for all the stacks created.
--
-- <http://docs.aws.amazon.com/AWSCloudFormation/latest/APIReference/API_DescribeStacks.html>
module Network.AWS.CloudFormation.DescribeStacks
    (
    -- * Request
      DescribeStacks
    -- ** Request constructor
    , describeStacks
    -- ** Request lenses
    , ds1NextToken
    , ds1StackName

    -- * Response
    , DescribeStacksResponse
    -- ** Response constructor
    , describeStacksResponse
    -- ** Response lenses
    , dsrNextToken
    , dsrStacks
    ) where

import Network.AWS.Prelude
import Network.AWS.Request.Query
import Network.AWS.CloudFormation.Types
import qualified GHC.Exts

data DescribeStacks = DescribeStacks
    { _ds1NextToken :: Maybe Text
    , _ds1StackName :: Maybe Text
    } deriving (Eq, Ord, Read, Show)

-- | 'DescribeStacks' constructor.
--
-- The fields accessible through corresponding lenses are:
--
-- * 'ds1NextToken' @::@ 'Maybe' 'Text'
--
-- * 'ds1StackName' @::@ 'Maybe' 'Text'
--
describeStacks :: DescribeStacks
describeStacks = DescribeStacks
    { _ds1StackName = Nothing
    , _ds1NextToken = Nothing
    }

-- | String that identifies the start of the next list of stacks, if there is one.
ds1NextToken :: Lens' DescribeStacks (Maybe Text)
ds1NextToken = lens _ds1NextToken (\s a -> s { _ds1NextToken = a })

-- | The name or the unique identifier associated with the stack, which are not
-- always interchangeable:
--
-- Running stacks: You can specify either the stack's name or its unique stack
-- ID. Deleted stacks: You must specify the unique stack ID.  Default: There is
-- no default value.
ds1StackName :: Lens' DescribeStacks (Maybe Text)
ds1StackName = lens _ds1StackName (\s a -> s { _ds1StackName = a })

data DescribeStacksResponse = DescribeStacksResponse
    { _dsrNextToken :: Maybe Text
    , _dsrStacks    :: List "member" Stack
    } deriving (Eq, Read, Show)

-- | 'DescribeStacksResponse' constructor.
--
-- The fields accessible through corresponding lenses are:
--
-- * 'dsrNextToken' @::@ 'Maybe' 'Text'
--
-- * 'dsrStacks' @::@ ['Stack']
--
describeStacksResponse :: DescribeStacksResponse
describeStacksResponse = DescribeStacksResponse
    { _dsrStacks    = mempty
    , _dsrNextToken = Nothing
    }

-- | String that identifies the start of the next list of stacks, if there is one.
dsrNextToken :: Lens' DescribeStacksResponse (Maybe Text)
dsrNextToken = lens _dsrNextToken (\s a -> s { _dsrNextToken = a })

-- | A list of stack structures.
dsrStacks :: Lens' DescribeStacksResponse [Stack]
dsrStacks = lens _dsrStacks (\s a -> s { _dsrStacks = a }) . _List

instance ToPath DescribeStacks where
    toPath = const "/"

instance ToQuery DescribeStacks where
    toQuery DescribeStacks{..} = mconcat
        [ "NextToken" =? _ds1NextToken
        , "StackName" =? _ds1StackName
        ]

instance ToHeaders DescribeStacks

instance AWSRequest DescribeStacks where
    type Sv DescribeStacks = CloudFormation
    type Rs DescribeStacks = DescribeStacksResponse

    request  = post "DescribeStacks"
    response = xmlResponse

instance FromXML DescribeStacksResponse where
    parseXML = withElement "DescribeStacksResult" $ \x -> DescribeStacksResponse
        <$> x .@? "NextToken"
        <*> x .@? "Stacks" .!@ mempty

instance AWSPager DescribeStacks where
    page rq rs
        | stop (rq ^. ds1NextToken) = Nothing
        | otherwise = (\x -> rq & ds1NextToken ?~ x)
            <$> (rs ^. dsrNextToken)