Add serviceStatus and serviceSendAction admin APIs (#100)

.gitignore

@@ -17,3 +17,4 @@ cabal.sandbox.config
 *.eventlog
 .stack-work/
 cabal.project.local
+*~

examples/ServiceSendRestart.hs

@@ -0,0 +1,30 @@
+#!/usr/bin/env stack
+-- stack --resolver lts-11.1 runghc --package minio-hs
+
+--
+-- Minio Haskell SDK, (C) 2017, 2018 Minio, Inc.
+--
+-- Licensed under the Apache License, Version 2.0 (the "License");
+-- you may not use this file except in compliance with the License.
+-- You may obtain a copy of the License at
+--
+--     http://www.apache.org/licenses/LICENSE-2.0
+--
+-- Unless required by applicable law or agreed to in writing, software
+-- distributed under the License is distributed on an "AS IS" BASIS,
+-- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+-- See the License for the specific language governing permissions and
+-- limitations under the License.
+--
+
+{-# LANGUAGE OverloadedStrings #-}
+import           Network.Minio
+import           Network.Minio.AdminAPI
+
+import           Prelude
+
+main :: IO ()
+main = do
+  res <- runMinio def $
+    serviceSendAction ServiceActionRestart
+  print res

examples/ServiceSendStop.hs

@@ -0,0 +1,30 @@
+#!/usr/bin/env stack
+-- stack --resolver lts-11.1 runghc --package minio-hs
+
+--
+-- Minio Haskell SDK, (C) 2017, 2018 Minio, Inc.
+--
+-- Licensed under the Apache License, Version 2.0 (the "License");
+-- you may not use this file except in compliance with the License.
+-- You may obtain a copy of the License at
+--
+--     http://www.apache.org/licenses/LICENSE-2.0
+--
+-- Unless required by applicable law or agreed to in writing, software
+-- distributed under the License is distributed on an "AS IS" BASIS,
+-- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+-- See the License for the specific language governing permissions and
+-- limitations under the License.
+--
+
+{-# LANGUAGE OverloadedStrings #-}
+import           Network.Minio
+import           Network.Minio.AdminAPI
+
+import           Prelude
+
+main :: IO ()
+main = do
+  res <- runMinio def $
+    serviceSendAction ServiceActionStop
+  print res

examples/ServiceStatus.hs

@@ -0,0 +1,30 @@
+#!/usr/bin/env stack
+-- stack --resolver lts-11.1 runghc --package minio-hs
+
+--
+-- Minio Haskell SDK, (C) 2017, 2018 Minio, Inc.
+--
+-- Licensed under the Apache License, Version 2.0 (the "License");
+-- you may not use this file except in compliance with the License.
+-- You may obtain a copy of the License at
+--
+--     http://www.apache.org/licenses/LICENSE-2.0
+--
+-- Unless required by applicable law or agreed to in writing, software
+-- distributed under the License is distributed on an "AS IS" BASIS,
+-- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+-- See the License for the specific language governing permissions and
+-- limitations under the License.
+--
+
+{-# LANGUAGE OverloadedStrings #-}
+import           Network.Minio
+import           Network.Minio.AdminAPI
+
+import           Prelude
+
+main :: IO ()
+main = do
+  res <- runMinio def $
+    serviceStatus
+  print res

src/Network/Minio/AdminAPI.hs

@@ -44,6 +44,13 @@ module Network.Minio.AdminAPI
   , NodeSummary(..)
   , setConfig
   , getConfig
+
+  , ServerVersion(..)
+  , ServiceStatus(..)
+  , serviceStatus
+
+  , ServiceAction(..)
+  , serviceSendAction
   ) where
 
 import           Data.Aeson                (FromJSON, ToJSON, Value (Object),
@@ -220,6 +227,40 @@ instance FromJSON ServerInfo where
         <*> v .: "addr"
         <*> v .: "data"
 
+data ServerVersion = ServerVersion
+  { svVersion  :: Text
+  , svCommitId :: Text
+  } deriving (Eq, Show)
+
+instance FromJSON ServerVersion where
+    parseJSON = withObject "ServerVersion" $ \v -> ServerVersion
+      <$> v .: "version"
+      <*> v .: "commitID"
+
+data ServiceStatus = ServiceStatus
+  { ssVersion :: ServerVersion
+  , ssUptime  :: NominalDiffTime
+  } deriving (Eq, Show)
+
+instance FromJSON ServiceStatus where
+    parseJSON = withObject "ServiceStatus" $ \v -> do
+      serverVersion <- v .: "serverVersion"
+      uptimeNs <- v .: "uptime"
+      let uptime = uptimeNs / 1e9
+      return $ ServiceStatus serverVersion uptime
+
+data ServiceAction = ServiceActionRestart
+                   | ServiceActionStop
+                   deriving (Eq, Show)
+
+instance ToJSON ServiceAction where
+    toJSON a = object [ "action" .= serviceActionToText a ]
+
+serviceActionToText :: ServiceAction -> Text
+serviceActionToText a = case a of
+  ServiceActionRestart -> "restart"
+  ServiceActionStop    -> "stop"
+
 adminPath :: ByteString
 adminPath = "/minio/admin"
 
@@ -344,6 +385,34 @@ healPath bucket prefix = do
          <> fromMaybe "" prefix
     else encodeUtf8 $ "v1/heal/"
 
+-- | Get server version and uptime.
+serviceStatus :: Minio ServiceStatus
+serviceStatus = do
+    rsp <- executeAdminRequest AdminReqInfo { ariMethod = HT.methodGet
+                                            , ariPayload = PayloadBS B.empty
+                                            , ariPayloadHash = Nothing
+                                            , ariPath = "v1/service"
+                                            , ariHeaders = []
+                                            , ariQueryParams = []
+                                            }
+
+    let rspBS = NC.responseBody rsp
+    case eitherDecode rspBS of
+        Right ss -> return ss
+        Left err -> throwIO $ MErrVJsonParse $ T.pack err
+
+-- | Send service restart or stop action to Minio server.
+serviceSendAction :: ServiceAction -> Minio ()
+serviceSendAction action = do
+    let payload = PayloadBS $ LBS.toStrict $ A.encode action
+    void $ executeAdminRequest AdminReqInfo { ariMethod = HT.methodPost
+                                            , ariPayload = payload
+                                            , ariPayloadHash = Nothing
+                                            , ariPath = "v1/service"
+                                            , ariHeaders = []
+                                            , ariQueryParams = []
+                                            }
+
 -- | Get the current config file from server.
 getConfig :: Minio ByteString
 getConfig = do