Merge pull request #38 from brandonchinn178/unsafe-lift-sql

Add unsafeLiftSql

Author: brandonchinn178

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Unreleased
 
+# 0.3.0.0
+
+* Add `unsafeLiftSql` ([#38](https://github.com/brandonchinn178/persistent-mtl/pull/38))
+
 # 0.2.2.0
 
 * Fix for persistent 2.13

package.yaml

@@ -1,5 +1,5 @@
 name: persistent-mtl
-version: 0.2.2.0
+version: 0.3.0.0
 maintainer: Brandon Chinn <[email protected]>
 synopsis: Monad transformer for the persistent API
 description: |
@@ -41,6 +41,7 @@ tests:
       - bytestring
       - conduit
       - containers
+      - esqueleto
       - monad-logger
       - persistent
       - persistent-mtl

persistent-mtl.cabal

@@ -5,7 +5,7 @@ cabal-version: 1.12
 -- see: https://github.com/sol/hpack
 
 name:           persistent-mtl
-version:        0.2.2.0
+version:        0.3.0.0
 synopsis:       Monad transformer for the persistent API
 description:    A monad transformer and mtl-style type class for using the
                 persistent API directly in your monad transformer stack.
@@ -69,6 +69,7 @@ test-suite persistent-mtl-test
       MockSqlQueryT
       SqlQueryRepTest
       TestUtils.DB
+      TestUtils.Esqueleto
       TestUtils.Match
       Paths_persistent_mtl
   hs-source-dirs:
@@ -79,6 +80,7 @@ test-suite persistent-mtl-test
     , bytestring
     , conduit
     , containers
+    , esqueleto
     , monad-logger
     , persistent
     , persistent-mtl

scripts/generate/templates/Shim.mustache

@@ -13,6 +13,7 @@ This file is autogenerated, to keep it in sync with
 {-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE GADTs #-}
 {-# LANGUAGE PatternSynonyms #-}
+{-# LANGUAGE RankNTypes #-}
 
 module Database.Persist.Monad.Shim where
 
@@ -49,6 +50,22 @@ import Database.Persist.Monad.SqlQueryRep (SqlQueryRep(..))
 {{/withCondition}}
 
 {{/functions}}
+-- | Lift an arbitrary 'SqlPersistT' action into 'MonadSqlQuery'.
+--
+-- This is unsafe because the action may be rerun. This function should
+-- primarily be used to interop with other libraries built on top of
+-- persistent.
+--
+-- Example usage:
+--
+-- @
+-- -- | Run an esqueleto select.
+-- select :: (MonadSqlQuery m, E.SqlSelect a r) => E.SqlQuery a -> m [r]
+-- select q = unsafeLiftSql "esqueleto-select" (E.select q)
+-- @
+unsafeLiftSql :: MonadSqlQuery m => Text -> (forall m2. MonadIO m2 => SqlPersistT m2 a) -> m a
+unsafeLiftSql label action = runQueryRep $ UnsafeLiftSql label action
+
 {- Helpers -}
 
 -- | A helper for functions that return a conduit.

scripts/generate/templates/SqlQueryRep.mustache

@@ -15,6 +15,7 @@ This file is autogenerated, to keep it in sync with
 {-# LANGUAGE GADTs #-}
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE PatternSynonyms #-}
+{-# LANGUAGE RankNTypes #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE TypeApplications #-}
 
@@ -31,6 +32,7 @@ import Data.Int (Int64)
 import Data.Map (Map)
 import Data.Proxy (Proxy(..))
 import Data.Text (Text)
+import qualified Data.Text as Text
 import Data.Typeable (Typeable, eqT, typeRep, (:~:)(..))
 import Data.Void (Void)
 import Database.Persist.Sql as Persist hiding (pattern Update)
@@ -57,13 +59,18 @@ data SqlQueryRep record a where
 {{/withCondition}}
 
 {{/sqlQueryRepConstructors}}
+  -- | Constructor for lifting an arbitrary SqlPersistT action into SqlQueryRep.
+  UnsafeLiftSql
+    :: Text -> (forall m. MonadIO m => Persist.SqlPersistT m a) -> SqlQueryRep Void a
+
 instance Typeable record => Show (SqlQueryRep record a) where
   show = \case
 {{#sqlQueryRepConstructors}}
 {{#withCondition}}
     {{{nameCapital}}}{} -> "{{{nameCapital}}}{..}" ++ record
 {{/withCondition}}
 {{/sqlQueryRepConstructors}}
+    UnsafeLiftSql label _ -> "UnsafeLiftSql{" ++ Text.unpack label ++ "}"
     where
       record = case recordTypeRep of
         Just recordType -> "<" ++ show recordType ++ ">"
@@ -81,3 +88,4 @@ runSqlQueryRep = \case
   {{{nameCapital}}} {{#args}}a{{index}} {{/args}}-> Persist.{{{name}}}{{#args}} a{{index}}{{/args}}
 {{/withCondition}}
 {{/sqlQueryRepConstructors}}
+  UnsafeLiftSql _ action -> action

src/Database/Persist/Monad/Shim.hs

@@ -13,6 +13,7 @@ This file is autogenerated, to keep it in sync with
 {-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE GADTs #-}
 {-# LANGUAGE PatternSynonyms #-}
+{-# LANGUAGE RankNTypes #-}
 
 module Database.Persist.Monad.Shim where
 
@@ -516,6 +517,22 @@ transactionUndoWithIsolation
 transactionUndoWithIsolation a1 = runQueryRep $ TransactionUndoWithIsolation a1
 #endif
 
+-- | Lift an arbitrary 'SqlPersistT' action into 'MonadSqlQuery'.
+--
+-- This is unsafe because the action may be rerun. This function should
+-- primarily be used to interop with other libraries built on top of
+-- persistent.
+--
+-- Example usage:
+--
+-- @
+-- -- | Run an esqueleto select.
+-- select :: (MonadSqlQuery m, E.SqlSelect a r) => E.SqlQuery a -> m [r]
+-- select q = unsafeLiftSql "esqueleto-select" (E.select q)
+-- @
+unsafeLiftSql :: MonadSqlQuery m => Text -> (forall m2. MonadIO m2 => SqlPersistT m2 a) -> m a
+unsafeLiftSql label action = runQueryRep $ UnsafeLiftSql label action
+
 {- Helpers -}
 
 -- | A helper for functions that return a conduit.

src/Database/Persist/Monad/SqlQueryRep.hs

@@ -15,6 +15,7 @@ This file is autogenerated, to keep it in sync with
 {-# LANGUAGE GADTs #-}
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE PatternSynonyms #-}
+{-# LANGUAGE RankNTypes #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE TypeApplications #-}
 
@@ -31,6 +32,7 @@ import Data.Int (Int64)
 import Data.Map (Map)
 import Data.Proxy (Proxy(..))
 import Data.Text (Text)
+import qualified Data.Text as Text
 import Data.Typeable (Typeable, eqT, typeRep, (:~:)(..))
 import Data.Void (Void)
 import Database.Persist.Sql as Persist hiding (pattern Update)
@@ -440,6 +442,10 @@ data SqlQueryRep record a where
     => IsolationLevel -> SqlQueryRep Void ()
 #endif
 
+  -- | Constructor for lifting an arbitrary SqlPersistT action into SqlQueryRep.
+  UnsafeLiftSql
+    :: Text -> (forall m. MonadIO m => Persist.SqlPersistT m a) -> SqlQueryRep Void a
+
 instance Typeable record => Show (SqlQueryRep record a) where
   show = \case
     Get{} -> "Get{..}" ++ record
@@ -546,6 +552,7 @@ instance Typeable record => Show (SqlQueryRep record a) where
 #if MIN_VERSION_persistent(2,9,0)
     TransactionUndoWithIsolation{} -> "TransactionUndoWithIsolation{..}" ++ record
 #endif
+    UnsafeLiftSql label _ -> "UnsafeLiftSql{" ++ Text.unpack label ++ "}"
     where
       record = case recordTypeRep of
         Just recordType -> "<" ++ show recordType ++ ">"
@@ -662,3 +669,4 @@ runSqlQueryRep = \case
 #if MIN_VERSION_persistent(2,9,0)
   TransactionUndoWithIsolation a1 -> Persist.transactionUndoWithIsolation a1
 #endif
+  UnsafeLiftSql _ action -> action

stack-ghc-8.10.yaml

@@ -1,4 +1,4 @@
-resolver: nightly-2021-06-01
+resolver: lts-18.4
 
 extra-deps:
 - persistent-postgresql-2.13.0.2

stack-ghc-8.2.yaml

@@ -3,6 +3,7 @@ resolver: lts-11.22
 extra-deps:
   - unliftio-core-0.1.2.0
   - unliftio-pool-0.2.0.0
+  - esqueleto-3.0.0
 
 ghc-options:
   "$locals": -Werror

stack-ghc-8.4.yaml

@@ -2,6 +2,7 @@ resolver: lts-12.26
 
 extra-deps:
   - unliftio-pool-0.2.1.0
+  - esqueleto-3.0.0
 
 ghc-options:
   "$locals": -Werror

stack-ghc-8.6.yaml

@@ -1,4 +1,7 @@
 resolver: lts-14.27
 
+extra-deps:
+  - esqueleto-3.0.0
+
 ghc-options:
   "$locals": -Werror

test/Integration.hs

@@ -15,6 +15,11 @@ import qualified Data.Map.Strict as Map
 import Data.Text (Text)
 import qualified Data.Text as Text
 import Data.Typeable (Typeable)
+#if MIN_VERSION_esqueleto(3,5,0)
+import qualified Database.Esqueleto.Experimental as E
+#else
+import qualified Database.Esqueleto as E
+#endif
 import Database.Persist.Sql
     ( Entity(..)
     , Migration
@@ -48,6 +53,7 @@ import Control.Monad.IO.Rerunnable (MonadRerunnableIO, rerunnableIO)
 import Database.Persist.Monad
 import Example
 import TestUtils.DB (BackendType(..), allBackendTypes)
+import TestUtils.Esqueleto (esqueletoSelect)
 import TestUtils.Match (Match(..), (@?~))
 
 tests :: TestTree
@@ -59,6 +65,7 @@ testsWithBackend backendType = testGroup (show backendType)
   [ testWithTransaction backendType
   , testComposability backendType
   , testPersistentAPI backendType
+  , testInterop backendType
   ]
 
 testWithTransaction :: BackendType -> TestTree
@@ -822,6 +829,21 @@ testPersistentAPI backendType = testGroup "Persistent API"
 #endif
   ]
 
+testInterop :: BackendType -> TestTree
+testInterop backendType = testGroup "Interop with third-party Persistent libraries"
+  [ testCase "unsafeLiftSql" $ do
+      let alice = person "Alice"
+      result <- runTestApp backendType $ do
+        insert_ alice
+        esqueletoSelect $
+#if MIN_VERSION_esqueleto(3,5,0)
+          E.from $ E.table @Person
+#else
+          E.from $ \p -> return p
+#endif
+      result @?= [Entity 1 alice]
+  ]
+
 {- Persistent helpers -}
 
 fromPersistValue' :: PersistField a => PersistValue -> a

test/TestUtils/Esqueleto.hs

@@ -0,0 +1,19 @@
+{-# LANGUAGE CPP #-}
+{-# LANGUAGE OverloadedStrings #-}
+
+module TestUtils.Esqueleto
+  ( esqueletoSelect
+  ) where
+
+#if MIN_VERSION_esqueleto(3,5,0)
+import qualified Database.Esqueleto.Experimental as E
+import qualified Database.Esqueleto.Internal.Internal as E
+#else
+import qualified Database.Esqueleto as E
+import qualified Database.Esqueleto.Internal.Sql as E
+#endif
+
+import Database.Persist.Monad (MonadSqlQuery, unsafeLiftSql)
+
+esqueletoSelect :: (MonadSqlQuery m, E.SqlSelect a r) => E.SqlQuery a -> m [r]
+esqueletoSelect q = unsafeLiftSql "esqueleto-select" (E.select q)