Add server-unix-socket config option (#1303)

Add ncat workaround to test socket connection on CircleCI

.circleci/config.yml

@@ -66,6 +66,11 @@ jobs:
       - restore_cache:
           keys:
           - v1-stack-dependencies-{{ checksum "postgrest.cabal" }}-{{ checksum "stack.yaml" }}
+      - run:
+          name: install ncat
+          command: |
+            # utility needed to test socket connection with curl <  7.40
+            sudo apt-get install nmap
       - run:
           name: install stack & dependencies
           command: |

CHANGELOG.md

@@ -7,6 +7,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Added
 
+- #1186, Add support for user defined unix socket via `server-unix-socket` config option
 - #690, Add `?columns` query parameter for faster bulk inserts, also ignores unspecified json keys in a payload - @steve-chavez
 - #1239, Add support for resource embedding on materialized views - @vitorbaptista
 - #1264, Add support for bulk RPC call - @steve-chavez

main/Main.hs

@@ -15,13 +15,22 @@ import Control.Retry            (RetryStatus, capDelay,
 import Data.IORef               (IORef, atomicWriteIORef, newIORef,
                                  readIORef)
 import Data.String              (IsString (..))
-import Data.Text                (pack, replace, strip, stripPrefix)
+import Data.Text                (pack, replace, strip, stripPrefix,
+                                 unpack)
 import Data.Text.Encoding       (decodeUtf8, encodeUtf8)
 import Data.Text.IO             (hPutStrLn, readFile)
 import Data.Time.Clock          (getCurrentTime)
+import Network.Socket           (Family (AF_UNIX),
+                                 SockAddr (SockAddrUnix), Socket,
+                                 SocketType (Stream), bind, close,
+                                 defaultProtocol, listen,
+                                 maxListenQueue, socket)
 import Network.Wai.Handler.Warp (defaultSettings, runSettings,
-                                 setHost, setPort, setServerName)
+                                 runSettingsSocket, setHost, setPort,
+                                 setServerName)
+import System.Directory         (removeFile)
 import System.IO                (BufferMode (..), hSetBuffering)
+import System.IO.Error          (isDoesNotExistError)
 
 import PostgREST.App         (postgrest)
 import PostgREST.Config      (AppConfig (..), configPoolTimeout',
@@ -153,6 +162,7 @@ main = do
   let host = configHost conf
       port = configPort conf
       proxy = configProxyUri conf
+      maybeSocketAddr = configSocket conf
       pgSettings = toS (configDatabase conf) -- is the db-uri
       roleClaimKey = configRoleClaimKey conf
       appSettings =
@@ -170,7 +180,6 @@ main = do
   when (isLeft roleClaimKey) $
     panic $ show roleClaimKey
 
-  putStrLn $ ("Listening on port " :: Text) <> show (configPort conf)
   --
   -- create connection pool with the provided settings, returns either
   -- a 'Connection' or a 'ConnectionError'. Does not throw.
@@ -222,19 +231,31 @@ main = do
   -- ask for the OS time at most once per second
   getTime <- mkAutoUpdate defaultUpdateSettings {updateAction = getCurrentTime}
 
-  -- run the postgrest application
-  runSettings appSettings $
-    postgrest
-      conf
-      refDbStructure
-      pool
-      getTime
-      (connectionWorker
-         mainTid
-         pool
-         (configSchema conf)
-         refDbStructure
-         refIsWorkerOn)
+  let postgrestApplication =
+        postgrest
+          conf
+          refDbStructure
+          pool
+          getTime
+          (connectionWorker
+             mainTid
+             pool
+             (configSchema conf)
+             refDbStructure
+             refIsWorkerOn)
+    in case maybeSocketAddr of
+         Nothing -> do
+             -- run the postgrest application
+             putStrLn $ ("Listening on port " :: Text) <> show (configPort conf)
+             runSettings appSettings postgrestApplication
+         Just socketAddr -> do
+             -- run postgrest application with user defined socket
+             sock <- createAndBindSocket (unpack socketAddr)
+             listen sock maxListenQueue
+             putStrLn $ ("Listening on unix socket " :: Text) <> show socketAddr
+             runSettingsSocket appSettings sock postgrestApplication
+             -- clean socket up when done
+             close sock
 
 {-|
   The purpose of this function is to load the JWT secret from a file if
@@ -302,3 +323,15 @@ loadDbUriFile conf = extractDbUri mDbUri
         Nothing       -> return dbUri
         Just filename -> strip <$> readFile (toS filename)
     setDbUri dbUri = conf {configDatabase = dbUri}
+
+createAndBindSocket :: FilePath -> IO Socket
+createAndBindSocket filePath = do
+  deleteSocketFileIfExist filePath
+  sock <- socket AF_UNIX Stream defaultProtocol
+  bind sock $ SockAddrUnix filePath
+  return sock
+  where
+    deleteSocketFileIfExist path = removeFile path `catch` handleDoesNotExist
+    handleDoesNotExist e
+      | isDoesNotExistError e = return ()
+      | otherwise = throwIO e

postgrest.cabal

@@ -33,17 +33,20 @@ executable postgrest
   default-language:    Haskell2010
   build-depends:       auto-update
                      , base >= 4.8 && < 4.10
-                     , base64-bytestring
-                     , bytestring
                      , hasql >= 1.3 && < 1.4
                      , hasql-pool >= 0.5 && < 0.6
                      , hasql-transaction >= 0.7 && < 0.8
+                     , network == 2.6.3.2
                      , postgrest
                      , protolude == 0.2.2
                      , retry
                      , text
                      , time
                      , warp
+                     , bytestring
+                     , base64-bytestring
+                     , retry
+                     , directory
   if !os(windows)
     build-depends:     unix
 

src/PostgREST/Config.hs

@@ -70,6 +70,7 @@ data AppConfig = AppConfig {
   , configSchema            :: Text
   , configHost              :: Text
   , configPort              :: Int
+  , configSocket            :: Maybe Text
 
   , configJwtSecret         :: Maybe B.ByteString
   , configJwtSecretIsBase64 :: Bool
@@ -149,6 +150,7 @@ readOptions = do
         <*> reqString "db-schema"
         <*> (fromMaybe "!4" . mfilter (/= "") <$> optString "server-host")
         <*> (fromMaybe 3000 . join . fmap coerceInt <$> optValue "server-port")
+        <*> optString "server-unix-socket"
         <*> (fmap encodeUtf8 . mfilter (/= "") <$> optString "jwt-secret")
         <*> (fromMaybe False . join . fmap coerceBool <$> optValue "secret-is-base64")
         <*> parseJwtAudience "jwt-aud"
@@ -231,6 +233,10 @@ readOptions = do
           |server-host = "!4"
           |server-port = 3000
           |
+          |## unix socket location
+          |## if specified it takes precedence over server-port
+          |# server-unix-socket = "/tmp/pgrst.sock"
+          |
           |## base url for swagger output
           |# server-proxy-uri = ""
           |

test/SpecHelper.hs

@@ -64,6 +64,8 @@ getEnvVarWithDefault var def = toS <$>
 _baseCfg :: AppConfig
 _baseCfg =  -- Connection Settings
   AppConfig mempty "postgrest_test_anonymous" Nothing "test" "localhost" 3000
+            -- No user configured Unix Socket
+            Nothing
             -- Jwt settings
             (Just $ encodeUtf8 "reallyreallyreallyreallyverysafe") False Nothing
             -- Connection Modifiers

test/io-tests.sh

@@ -181,6 +181,30 @@ ensureAppSettings(){
   pgrStop
 }
 
+getSocketStatus() {
+  curl -sL -w "%{http_code}\\n" -o /dev/null localhost:54321
+}
+
+socketConnection(){
+  # map port 54321 traffic to unix socket as workaround for curl below 7.40
+  # not supporting --unix-socket flag
+  ncat -vlk 54321 -c 'ncat -U /tmp/postgrest.sock' &
+  pgrStart "./configs/unix-socket.config"
+  while pgrStarted && test "$( getSocketStatus )" -ne 200
+  do
+    # wait for the server to start
+    sleep 0.1 \
+    || sleep 1 # fallback: subsecond sleep is not standard and may fail
+  done
+  if test $( getSocketStatus ) -eq 200
+  then
+    ok "Succesfully connected through unix socket"
+  else
+    ko "Failed to connect through unix socket"
+  fi
+  pgrStop
+}
+
 # PRE: curl must be available
 test -n "$(command -v curl)" || bailOut 'curl is not available'
 
@@ -191,6 +215,8 @@ setUp
 
 echo "Running IO tests.."
 
+socketConnection
+
 readSecretFromFile word.noeol 'simple (no EOL)'
 readSecretFromFile word.txt 'simple'
 readSecretFromFile ascii.noeol 'ASCII (no EOL)'
@@ -224,6 +250,7 @@ invalidRoleClaimKey 1234
 ensureIatClaimWorks
 ensureAppSettings
 
+
 cleanUp
 
 exit $failedTests

test/io-tests/configs/unix-socket.config

@@ -0,0 +1,7 @@
+db-uri = "postgres:///postgrest_test"
+db-schema = "test"
+db-anon-role = "postgrest_test_anonymous"
+db-pool = 1
+server-host = "127.0.0.1"
+server-unix-socket = "/tmp/postgrest.sock"
+jwt-secret = "reallyreallyreallyreallyverysafe"