diff --git a/CHANGELOG.md b/CHANGELOG.md new file mode 100644 --- /dev/null +++ b/CHANGELOG.md @@ -0,0 +1,11 @@ +# Changelog + +`postgresql-simple-named` uses [PVP Versioning][1]. +The changelog is available [on GitHub][2]. + +## 0.0.0.0 — Jul 11, 2019 + +* Initially created. + +[1]: https://pvp.haskell.org +[2]: https://github.com/Holmusk/postgresql-simple-named/releases diff --git a/LICENSE b/LICENSE new file mode 100644 --- /dev/null +++ b/LICENSE @@ -0,0 +1,373 @@ +Mozilla Public License Version 2.0 +================================== + +1. Definitions +-------------- + +1.1. "Contributor" + means each individual or legal entity that creates, contributes to + the creation of, or owns Covered Software. + +1.2. "Contributor Version" + means the combination of the Contributions of others (if any) used + by a Contributor and that particular Contributor's Contribution. + +1.3. "Contribution" + means Covered Software of a particular Contributor. + +1.4. "Covered Software" + means Source Code Form to which the initial Contributor has attached + the notice in Exhibit A, the Executable Form of such Source Code + Form, and Modifications of such Source Code Form, in each case + including portions thereof. + +1.5. "Incompatible With Secondary Licenses" + means + + (a) that the initial Contributor has attached the notice described + in Exhibit B to the Covered Software; or + + (b) that the Covered Software was made available under the terms of + version 1.1 or earlier of the License, but not also under the + terms of a Secondary License. + +1.6. "Executable Form" + means any form of the work other than Source Code Form. + +1.7. "Larger Work" + means a work that combines Covered Software with other material, in + a separate file or files, that is not Covered Software. + +1.8. "License" + means this document. + +1.9. "Licensable" + means having the right to grant, to the maximum extent possible, + whether at the time of the initial grant or subsequently, any and + all of the rights conveyed by this License. + +1.10. "Modifications" + means any of the following: + + (a) any file in Source Code Form that results from an addition to, + deletion from, or modification of the contents of Covered + Software; or + + (b) any new file in Source Code Form that contains any Covered + Software. + +1.11. "Patent Claims" of a Contributor + means any patent claim(s), including without limitation, method, + process, and apparatus claims, in any patent Licensable by such + Contributor that would be infringed, but for the grant of the + License, by the making, using, selling, offering for sale, having + made, import, or transfer of either its Contributions or its + Contributor Version. + +1.12. "Secondary License" + means either the GNU General Public License, Version 2.0, the GNU + Lesser General Public License, Version 2.1, the GNU Affero General + Public License, Version 3.0, or any later versions of those + licenses. + +1.13. "Source Code Form" + means the form of the work preferred for making modifications. + +1.14. "You" (or "Your") + means an individual or a legal entity exercising rights under this + License. For legal entities, "You" includes any entity that + controls, is controlled by, or is under common control with You. For + purposes of this definition, "control" means (a) the power, direct + or indirect, to cause the direction or management of such entity, + whether by contract or otherwise, or (b) ownership of more than + fifty percent (50%) of the outstanding shares or beneficial + ownership of such entity. + +2. License Grants and Conditions +-------------------------------- + +2.1. Grants + +Each Contributor hereby grants You a world-wide, royalty-free, +non-exclusive license: + +(a) under intellectual property rights (other than patent or trademark) + Licensable by such Contributor to use, reproduce, make available, + modify, display, perform, distribute, and otherwise exploit its + Contributions, either on an unmodified basis, with Modifications, or + as part of a Larger Work; and + +(b) under Patent Claims of such Contributor to make, use, sell, offer + for sale, have made, import, and otherwise transfer either its + Contributions or its Contributor Version. + +2.2. Effective Date + +The licenses granted in Section 2.1 with respect to any Contribution +become effective for each Contribution on the date the Contributor first +distributes such Contribution. + +2.3. Limitations on Grant Scope + +The licenses granted in this Section 2 are the only rights granted under +this License. No additional rights or licenses will be implied from the +distribution or licensing of Covered Software under this License. +Notwithstanding Section 2.1(b) above, no patent license is granted by a +Contributor: + +(a) for any code that a Contributor has removed from Covered Software; + or + +(b) for infringements caused by: (i) Your and any other third party's + modifications of Covered Software, or (ii) the combination of its + Contributions with other software (except as part of its Contributor + Version); or + +(c) under Patent Claims infringed by Covered Software in the absence of + its Contributions. + +This License does not grant any rights in the trademarks, service marks, +or logos of any Contributor (except as may be necessary to comply with +the notice requirements in Section 3.4). + +2.4. Subsequent Licenses + +No Contributor makes additional grants as a result of Your choice to +distribute the Covered Software under a subsequent version of this +License (see Section 10.2) or under the terms of a Secondary License (if +permitted under the terms of Section 3.3). + +2.5. Representation + +Each Contributor represents that the Contributor believes its +Contributions are its original creation(s) or it has sufficient rights +to grant the rights to its Contributions conveyed by this License. + +2.6. Fair Use + +This License is not intended to limit any rights You have under +applicable copyright doctrines of fair use, fair dealing, or other +equivalents. + +2.7. Conditions + +Sections 3.1, 3.2, 3.3, and 3.4 are conditions of the licenses granted +in Section 2.1. + +3. Responsibilities +------------------- + +3.1. Distribution of Source Form + +All distribution of Covered Software in Source Code Form, including any +Modifications that You create or to which You contribute, must be under +the terms of this License. You must inform recipients that the Source +Code Form of the Covered Software is governed by the terms of this +License, and how they can obtain a copy of this License. You may not +attempt to alter or restrict the recipients' rights in the Source Code +Form. + +3.2. Distribution of Executable Form + +If You distribute Covered Software in Executable Form then: + +(a) such Covered Software must also be made available in Source Code + Form, as described in Section 3.1, and You must inform recipients of + the Executable Form how they can obtain a copy of such Source Code + Form by reasonable means in a timely manner, at a charge no more + than the cost of distribution to the recipient; and + +(b) You may distribute such Executable Form under the terms of this + License, or sublicense it under different terms, provided that the + license for the Executable Form does not attempt to limit or alter + the recipients' rights in the Source Code Form under this License. + +3.3. Distribution of a Larger Work + +You may create and distribute a Larger Work under terms of Your choice, +provided that You also comply with the requirements of this License for +the Covered Software. If the Larger Work is a combination of Covered +Software with a work governed by one or more Secondary Licenses, and the +Covered Software is not Incompatible With Secondary Licenses, this +License permits You to additionally distribute such Covered Software +under the terms of such Secondary License(s), so that the recipient of +the Larger Work may, at their option, further distribute the Covered +Software under the terms of either this License or such Secondary +License(s). + +3.4. Notices + +You may not remove or alter the substance of any license notices +(including copyright notices, patent notices, disclaimers of warranty, +or limitations of liability) contained within the Source Code Form of +the Covered Software, except that You may alter any license notices to +the extent required to remedy known factual inaccuracies. + +3.5. Application of Additional Terms + +You may choose to offer, and to charge a fee for, warranty, support, +indemnity or liability obligations to one or more recipients of Covered +Software. However, You may do so only on Your own behalf, and not on +behalf of any Contributor. You must make it absolutely clear that any +such warranty, support, indemnity, or liability obligation is offered by +You alone, and You hereby agree to indemnify every Contributor for any +liability incurred by such Contributor as a result of warranty, support, +indemnity or liability terms You offer. You may include additional +disclaimers of warranty and limitations of liability specific to any +jurisdiction. + +4. Inability to Comply Due to Statute or Regulation +--------------------------------------------------- + +If it is impossible for You to comply with any of the terms of this +License with respect to some or all of the Covered Software due to +statute, judicial order, or regulation then You must: (a) comply with +the terms of this License to the maximum extent possible; and (b) +describe the limitations and the code they affect. Such description must +be placed in a text file included with all distributions of the Covered +Software under this License. Except to the extent prohibited by statute +or regulation, such description must be sufficiently detailed for a +recipient of ordinary skill to be able to understand it. + +5. Termination +-------------- + +5.1. The rights granted under this License will terminate automatically +if You fail to comply with any of its terms. However, if You become +compliant, then the rights granted under this License from a particular +Contributor are reinstated (a) provisionally, unless and until such +Contributor explicitly and finally terminates Your grants, and (b) on an +ongoing basis, if such Contributor fails to notify You of the +non-compliance by some reasonable means prior to 60 days after You have +come back into compliance. Moreover, Your grants from a particular +Contributor are reinstated on an ongoing basis if such Contributor +notifies You of the non-compliance by some reasonable means, this is the +first time You have received notice of non-compliance with this License +from such Contributor, and You become compliant prior to 30 days after +Your receipt of the notice. + +5.2. If You initiate litigation against any entity by asserting a patent +infringement claim (excluding declaratory judgment actions, +counter-claims, and cross-claims) alleging that a Contributor Version +directly or indirectly infringes any patent, then the rights granted to +You by any and all Contributors for the Covered Software under Section +2.1 of this License shall terminate. + +5.3. In the event of termination under Sections 5.1 or 5.2 above, all +end user license agreements (excluding distributors and resellers) which +have been validly granted by You or Your distributors under this License +prior to termination shall survive termination. + +************************************************************************ +* * +* 6. Disclaimer of Warranty * +* ------------------------- * +* * +* Covered Software is provided under this License on an "as is" * +* basis, without warranty of any kind, either expressed, implied, or * +* statutory, including, without limitation, warranties that the * +* Covered Software is free of defects, merchantable, fit for a * +* particular purpose or non-infringing. The entire risk as to the * +* quality and performance of the Covered Software is with You. * +* Should any Covered Software prove defective in any respect, You * +* (not any Contributor) assume the cost of any necessary servicing, * +* repair, or correction. This disclaimer of warranty constitutes an * +* essential part of this License. No use of any Covered Software is * +* authorized under this License except under this disclaimer. * +* * +************************************************************************ + +************************************************************************ +* * +* 7. Limitation of Liability * +* -------------------------- * +* * +* Under no circumstances and under no legal theory, whether tort * +* (including negligence), contract, or otherwise, shall any * +* Contributor, or anyone who distributes Covered Software as * +* permitted above, be liable to You for any direct, indirect, * +* special, incidental, or consequential damages of any character * +* including, without limitation, damages for lost profits, loss of * +* goodwill, work stoppage, computer failure or malfunction, or any * +* and all other commercial damages or losses, even if such party * +* shall have been informed of the possibility of such damages. This * +* limitation of liability shall not apply to liability for death or * +* personal injury resulting from such party's negligence to the * +* extent applicable law prohibits such limitation. Some * +* jurisdictions do not allow the exclusion or limitation of * +* incidental or consequential damages, so this exclusion and * +* limitation may not apply to You. * +* * +************************************************************************ + +8. Litigation +------------- + +Any litigation relating to this License may be brought only in the +courts of a jurisdiction where the defendant maintains its principal +place of business and such litigation shall be governed by laws of that +jurisdiction, without reference to its conflict-of-law provisions. +Nothing in this Section shall prevent a party's ability to bring +cross-claims or counter-claims. + +9. Miscellaneous +---------------- + +This License represents the complete agreement concerning the subject +matter hereof. If any provision of this License is held to be +unenforceable, such provision shall be reformed only to the extent +necessary to make it enforceable. Any law or regulation which provides +that the language of a contract shall be construed against the drafter +shall not be used to construe this License against a Contributor. + +10. Versions of the License +--------------------------- + +10.1. New Versions + +Mozilla Foundation is the license steward. Except as provided in Section +10.3, no one other than the license steward has the right to modify or +publish new versions of this License. Each version will be given a +distinguishing version number. + +10.2. Effect of New Versions + +You may distribute the Covered Software under the terms of the version +of the License under which You originally received the Covered Software, +or under the terms of any subsequent version published by the license +steward. + +10.3. Modified Versions + +If you create software not governed by this License, and you want to +create a new license for such software, you may create and use a +modified version of this License if you rename the license and remove +any references to the name of the license steward (except to note that +such modified license differs from this License). + +10.4. Distributing Source Code Form that is Incompatible With Secondary +Licenses + +If You choose to distribute Source Code Form that is Incompatible With +Secondary Licenses under the terms of this version of the License, the +notice described in Exhibit B of this License must be attached. + +Exhibit A - Source Code Form License Notice +------------------------------------------- + + This Source Code Form is subject to the terms of the Mozilla Public + License, v. 2.0. If a copy of the MPL was not distributed with this + file, You can obtain one at http://mozilla.org/MPL/2.0/. + +If it is not possible or desirable to put the notice in a particular +file, then You may include the notice in a location (such as a LICENSE +file in a relevant directory) where a recipient would be likely to look +for such a notice. + +You may add additional accurate notices of copyright ownership. + +Exhibit B - "Incompatible With Secondary Licenses" Notice +--------------------------------------------------------- + + This Source Code Form is "Incompatible With Secondary Licenses", as + defined by the Mozilla Public License, v. 2.0. diff --git a/README.md b/README.md new file mode 100644 --- /dev/null +++ b/README.md @@ -0,0 +1,82 @@ +# postgresql-simple-named + +[![Build status](https://img.shields.io/travis/Holmusk/postgresql-simple-named.svg?logo=travis)](https://travis-ci.org/Holmusk/postgresql-simple-named) +[![Hackage](https://img.shields.io/hackage/v/postgresql-simple-named.svg?logo=haskell)](https://hackage.haskell.org/package/postgresql-simple-named) +[![Stackage Lts](http://stackage.org/package/postgresql-simple-named/badge/lts)](http://stackage.org/lts/package/postgresql-simple-named) +[![Stackage Nightly](http://stackage.org/package/postgresql-simple-named/badge/nightly)](http://stackage.org/nightly/package/postgresql-simple-named) +[![MPL-2.0 license](https://img.shields.io/badge/license-MPL--2.0-blue.svg)](LICENSE) + +This library introduces the implementation of named parameters for the +[`postgresql-simple`][pgs] library. `postgresql-simple-named` is considered to +be used along with the [`postgresql-simple`][pgs] library, so you could refer +there for the original documentation of primary functions. This package solves +exclusively one particular problem — gives the ability to use named parameters +instead of `?` in quasi-quoter queries and offers essential functions for substituting +variables in queries (`queryNamed`, `executeNamed`). + +## Example + +Operator `=?` binds named parameters with the corresponding values. Named +parameters inside SQL query start with the '?' character and can contain +lowercase and uppercase letters, digits and underscore. Below you can find a +basic example of how query with named parameters could look like: + +```haskell +queryNamed dbConnection [sql| + SELECT + id, name, city + FROM users + WHERE name = ?nameParam + AND age = ?ageParam + +|] [ "nameParam" =? "John" + , "ageParam" =? 42 + ] +``` + +This feature can be extremely helpful when the query uses some parameters more than once: + +```haskell +query dbConnection [sql| + SELECT + col1, col2 + FROM my_table + WHERE id = ? + AND (? IS NULL OR id > ? ) + AND (? IS NULL OR id < ? ) + +|] (someId, minId, minId, maxId, maxId) +``` + +This is how the query looks like with the `postgresql-simple` library. You can +rewrite it the following way using the `postgresql-simple-named` library: + +```haskell +queryNamed dbConnection [sql| + SELECT + col1, col2 + FROM my_table + WHERE id = ?someId + AND (?minId IS NULL OR id > ?minId ) + AND (?maxId IS NULL OR id < ?maxId ) + +|] [ "someId" =? 42 + , "minId" =? 1 + , "maxId" =? 100 + ] +``` + +## How to build + +Build the library with either `cabal new-build` or `stack build`. + +## How to test locally + +* Run DB in a Docker in a separate terminal window using command: + ``` + docker run -p 5432\:5432 -e POSTGRES_USER=postgres -e POSTGRES_DB=pg_named postgres\:10.5-alpine + ``` +* Run tests using `cabal new-test` or `stack test` + + +[pgs]: https://hackage.haskell.org/package/postgresql-simple diff --git a/postgresql-simple-named.cabal b/postgresql-simple-named.cabal new file mode 100644 --- /dev/null +++ b/postgresql-simple-named.cabal @@ -0,0 +1,99 @@ +cabal-version: 2.4 +name: postgresql-simple-named +version: 0.0.0.0 +synopsis: Implementation of named parameters for `postgresql-simple` library +description: + Implementation of named parameters for @postgresql-simple@ library. + . + Here is an exaple of how it could be used in your code: + . + > queryNamed [sql| + > SELECT * + > FROM table + > WHERE foo = ?foo + > AND bar = ?bar + > AND baz = ?foo + > |] [ "foo" =? "fooBar" + > , "bar" =? "barVar" + > ] + +homepage: https://github.com/Holmusk/postgresql-simple-named +bug-reports: https://github.com/Holmusk/postgresql-simple-named/issues +license: MPL-2.0 +license-file: LICENSE +author: Dmitrii Kovanikov, Veronika Romashkina +maintainer: Holmusk +copyright: 2019 Holmusk +category: Database, PostgreSQL +build-type: Simple +extra-doc-files: README.md + , CHANGELOG.md +tested-with: GHC == 8.4.4 + , GHC == 8.6.5 + +source-repository head + type: git + location: https://github.com/Holmusk/postgresql-simple-named.git + +common common-options + build-depends: base >= 4.11 && < 4.13 + + ghc-options: -Wall + -Wincomplete-uni-patterns + -Wincomplete-record-updates + -Wcompat + -Widentities + -Wredundant-constraints + -fhide-source-paths + -Wmissing-export-lists + -Wpartial-fields + + default-language: Haskell2010 + default-extensions: ConstraintKinds + DeriveGeneric + GeneralizedNewtypeDeriving + InstanceSigs + KindSignatures + LambdaCase + OverloadedStrings + RecordWildCards + ScopedTypeVariables + StandaloneDeriving + TupleSections + TypeApplications + ViewPatterns + +library + import: common-options + hs-source-dirs: src + exposed-modules: PgNamed + build-depends: bytestring ^>= 0.10.8 + , mtl ^>= 2.2 + , postgresql-simple ^>= 0.6.2 + , text ^>= 1.2 + +test-suite postgresql-simple-named-test + import: common-options + type: exitcode-stdio-1.0 + hs-source-dirs: test + main-is: Spec.hs + + build-depends: bytestring + , hspec >= 2.6 && < 2.8 + , postgresql-simple-named + , postgresql-simple + , resource-pool ^>= 0.2.3.2 + , transformers + + ghc-options: -threaded -rtsopts -with-rtsopts=-N + +test-suite postgresql-simple-named-doctest + import: common-options + type: exitcode-stdio-1.0 + hs-source-dirs: test + main-is: Doctest.hs + + build-depends: doctest + , Glob + + ghc-options: -threaded diff --git a/src/PgNamed.hs b/src/PgNamed.hs new file mode 100644 --- /dev/null +++ b/src/PgNamed.hs @@ -0,0 +1,224 @@ +{-# LANGUAGE DerivingStrategies #-} +{-# LANGUAGE ExistentialQuantification #-} +{-# LANGUAGE FlexibleContexts #-} + +{- | Introduces named parameters for @postgresql-simple@ library. +It uses @?@ question mark symbol as the indicator of the named parameter which +is replaced with the standard syntax with question marks. + +Check out the example of usage: + +@ +'queryNamed' [sql| + SELECT * + FROM users + WHERE foo = ?foo + AND bar = ?bar + AND baz = ?foo +|] [ "foo" '=?' "fooBar" + , "bar" '=?' "barVar" + ] +@ +-} + +module PgNamed + ( -- * Named data types and smart constructors + NamedParam (..) + , Name (..) + , (=?) + + -- * Errors + , PgNamedError (..) + , WithNamedError + + -- * Functions to deal with named parameters + , extractNames + , namesToRow + + -- * Database querying functions with named parameters + , queryNamed + , executeNamed + ) where + +import Control.Monad.Except (MonadError (throwError)) +import Control.Monad.IO.Class (MonadIO (liftIO)) +import Data.Bifunctor (bimap) +import Data.ByteString (ByteString) +import Data.Char (isAlphaNum) +import Data.Int (Int64) +import Data.List (lookup) +import Data.List.NonEmpty (NonEmpty (..), toList) +import Data.Text (Text) +import Data.Text.Encoding (decodeUtf8) +import GHC.Exts (IsString) + +import qualified Data.ByteString.Char8 as BS +import qualified Database.PostgreSQL.Simple as PG +import qualified Database.PostgreSQL.Simple.ToField as PG +import qualified Database.PostgreSQL.Simple.Types as PG + + +-- | Wrapper over name of the argument. +newtype Name = Name + { unName :: Text + } deriving newtype (Show, Eq, Ord, IsString) + +-- | Data type to represent each named parameter. +data NamedParam = NamedParam + { namedParamName :: !Name + , namedParamParam :: !PG.Action + } deriving (Show) + +-- | @PostgreSQL@ error type for named parameters. +data PgNamedError + -- | Named parameter is not specified. + = PgNamedParam Name + -- | Query has no names inside but was called with named functions. + | PgNoNames PG.Query + -- | Query contains an empty name. + | PgEmptyName PG.Query + deriving (Eq) + + +-- | Type alias for monads that can throw errors of the 'PgNamedError' type. +type WithNamedError = MonadError PgNamedError + +instance Show PgNamedError where + show e = "PostgreSQL named parameter error: " ++ case e of + PgNamedParam n -> "Named parameter '" ++ show n ++ "' is not specified" + PgNoNames (PG.Query q) -> + "Query has no names but was called with named functions: " ++ BS.unpack q + PgEmptyName (PG.Query q) -> + "Query contains an empty name: " ++ BS.unpack q + +-- | Checks whether the 'Name' is in the list and returns its parameter. +lookupName :: Name -> [NamedParam] -> Maybe PG.Action +lookupName n = lookup n . map (\NamedParam{..} -> (namedParamName, namedParamParam)) + +{- | This function takes query with named parameters specified like this: + +@ +SELECT name, user FROM users WHERE id = ?id +@ + +and returns either the error or the query with all names replaced by +question marks @?@ with the list of the names in the order of their appearance. + +For example: + +>>> extractNames "SELECT * FROM users WHERE foo = ?foo AND bar = ?bar AND baz = ?foo" +Right ("SELECT * FROM users WHERE foo = ? AND bar = ? AND baz = ?","foo" :| ["bar","foo"]) +-} +extractNames + :: PG.Query + -> Either PgNamedError (PG.Query, NonEmpty Name) +extractNames qr = go (PG.fromQuery qr) >>= \case + (_, []) -> Left $ PgNoNames qr + (q, name:names) -> Right (PG.Query q, name :| names) + where + go :: ByteString -> Either PgNamedError (ByteString, [Name]) + go str + | BS.null str = Right ("", []) + | otherwise = let (before, after) = BS.break (== '?') str in + case BS.uncons after of + Nothing -> Right (before, []) + Just ('?', nameStart) -> + let (name, remainingQuery) = BS.span isNameChar nameStart + in if BS.null name + then Left $ PgEmptyName qr + else fmap (bimap ((before <> "?") <>) (Name (decodeUtf8 name) :)) + (go remainingQuery) + Just _ -> error "'break (== '?')' doesn't return string started with the question mark" + + isNameChar :: Char -> Bool + isNameChar c = isAlphaNum c || c == '_' + + +{- | Returns the list of values to use in query by given list of 'Name's. +Throws 'PgNamedError' if any named parameter is not specified. +-} +namesToRow + :: forall m . WithNamedError m + => NonEmpty Name -- ^ List of the names used in query + -> [NamedParam] -- ^ List of the named parameters + -> m (NonEmpty PG.Action) +namesToRow names params = traverse magicLookup names + where + magicLookup :: Name -> m PG.Action + magicLookup n = case lookupName n params of + Just x -> pure x + Nothing -> throwError $ PgNamedParam n + +{- | Operator to create 'NamedParam's. + +>>> "foo" =? (1 :: Int) +NamedParam {namedParamName = "foo", namedParamParam = Plain "1"} + +So it can be used in creating the list of the named arguments: + +@ +queryNamed [sql| + SELECT * FROM users WHERE foo = ?foo AND bar = ?bar AND baz = ?foo" +|] [ "foo" =? "fooBar" + , "bar" =? "barVar" + ] +@ +-} +infix 1 =? +(=?) :: (PG.ToField a) => Name -> a -> NamedParam +n =? a = NamedParam n $ PG.toField a +{-# INLINE (=?) #-} + +{- | Queries the database with a given query and named parameters +and expects a list of rows in return. + +@ +queryNamed dbConnection [sql| + SELECT id FROM table + WHERE foo = ?foo +|] [ "foo" '=?' "bar" ] +@ +-} +queryNamed + :: (MonadIO m, WithNamedError m, PG.FromRow res) + => PG.Connection -- ^ Database connection + -> PG.Query -- ^ Query with named parameters inside + -> [NamedParam] -- ^ The list of named parameters to be used in the query + -> m [res] -- ^ Resulting rows +queryNamed conn qNamed params = + withNamedArgs qNamed params >>= \(q, actions) -> + liftIO $ PG.query conn q (toList actions) + +{- | Modifies the database with a given query and named parameters +and expects a number of the rows affected. + +@ +executeNamed dbConnection [sql| + UPDATE table + SET foo = 'bar' + WHERE id = ?id +|] [ "id" '=?' someId ] +@ +-} +executeNamed + :: (MonadIO m, WithNamedError m) + => PG.Connection -- ^ Database connection + -> PG.Query -- ^ Query with named parameters inside + -> [NamedParam] -- ^ The list of named parameters to be used in the query + -> m Int64 -- ^ Number of the rows affected by the given query +executeNamed conn qNamed params = + withNamedArgs qNamed params >>= \(q, actions) -> + liftIO $ PG.execute conn q (toList actions) + +-- | Helper to use named parameters. +withNamedArgs + :: WithNamedError m + => PG.Query + -> [NamedParam] + -> m (PG.Query, NonEmpty PG.Action) +withNamedArgs qNamed namedArgs = do + (q, names) <- case extractNames qNamed of + Left errType -> throwError errType + Right r -> pure r + args <- namesToRow names namedArgs + pure (q, args) diff --git a/test/Doctest.hs b/test/Doctest.hs new file mode 100644 --- /dev/null +++ b/test/Doctest.hs @@ -0,0 +1,16 @@ +module Main (main) where + +import System.FilePath.Glob (glob) +import Test.DocTest (doctest) + +main :: IO () +main = do + sourceFiles <- glob "src/**/*.hs" + doctest + $ "-XConstraintKinds" + : "-XGeneralizedNewtypeDeriving" + : "-XLambdaCase" + : "-XOverloadedStrings" + : "-XRecordWildCards" + : "-XScopedTypeVariables" + : sourceFiles diff --git a/test/Spec.hs b/test/Spec.hs new file mode 100644 --- /dev/null +++ b/test/Spec.hs @@ -0,0 +1,66 @@ +{-# LANGUAGE DeriveAnyClass #-} +{-# LANGUAGE DerivingStrategies #-} + +module Main (main) where + +import Control.Monad.Trans.Except (ExceptT, runExceptT) +import Data.Bifunctor (second) +import Data.ByteString (ByteString) +import GHC.Generics (Generic) +import System.IO (hSetEncoding, stderr, stdout, utf8) +import Test.Hspec (Spec, describe, hspec, it, shouldReturn) + +import PgNamed (NamedParam, PgNamedError (..), queryNamed, (=?)) + +import qualified Data.Pool as Pool +import qualified Database.PostgreSQL.Simple as Sql + + +connectionSettings :: ByteString +connectionSettings = "host=localhost port=5432 user=postgres dbname=pg_named" + +main :: IO () +main = do + hSetEncoding stdout utf8 + hSetEncoding stderr utf8 + dbPool <- Pool.createPool (Sql.connectPostgreSQL connectionSettings) Sql.close 10 5 10 + hspec $ unitTests dbPool + +unitTests :: Pool.Pool Sql.Connection -> Spec +unitTests dbPool = describe "Testing: postgresql-simple-named" $ do + it "returns error when named parameter is not specified" $ + missingNamedParam `shouldReturn` Left (PgNamedParam "bar") + it "no named parameters in a query" $ + noNamedParams `shouldReturn` Left (PgNoNames "SELECT 42") + it "empty name in a query with named parameters" $ + emptyName `shouldReturn` Left (PgEmptyName "SELECT ?foo, ?") + it "named parameters are parsed and passed correctly" $ + queryTestValue `shouldReturn` Right (TestValue 42 42 "baz") + where + missingNamedParam :: IO (Either PgNamedError TestValue) + missingNamedParam = run "SELECT ?foo, ?bar" ["foo" =? True] + + noNamedParams :: IO (Either PgNamedError TestValue) + noNamedParams = run "SELECT 42" [] + + emptyName :: IO (Either PgNamedError TestValue) + emptyName = run "SELECT ?foo, ?" ["foo" =? True] + + queryTestValue :: IO (Either PgNamedError TestValue) + queryTestValue = run "SELECT ?intVal, ?intVal, ?txtVal" + [ "intVal" =? (42 :: Int) + , "txtVal" =? ("baz" :: ByteString) + ] + + run :: Sql.Query -> [NamedParam] -> IO (Either PgNamedError TestValue) + run q params = runNamedQuery $ Pool.withResource dbPool (\conn -> queryNamed conn q params) + +runNamedQuery :: ExceptT PgNamedError IO [TestValue] -> IO (Either PgNamedError TestValue) +runNamedQuery = fmap (second head) . runExceptT + +data TestValue = TestValue + { intVal1 :: !Int + , intVal2 :: !Int + , txtVal :: !ByteString + } deriving stock (Show, Eq, Generic) + deriving anyclass (Sql.FromRow, Sql.ToRow)