Version endpoint

default.nix

@@ -1,9 +1,9 @@
 { mkDerivation, aeson, annotated-exception, base, bytestring
 , containers, directory, ekg-core, exceptions, filepath
-, generic-lens, http-client, http-types, katip, lens, lens-aeson
-, lib, monad-control, mtl, optparse-generic, pandoc, pipes
-, pipes-concurrency, retry, servant, servant-server, stm, streamly
-, streamly-core, text, time, transformers-base, unliftio
+, generic-lens, githash, http-client, http-types, katip, lens
+, lens-aeson, lib, monad-control, mtl, optparse-generic, pandoc
+, pipes, pipes-concurrency, retry, servant, servant-server, stm
+, streamly, streamly-core, text, time, transformers-base, unliftio
 , unordered-containers, wai, warp, wreq
 }:
 mkDerivation {
@@ -14,14 +14,14 @@ mkDerivation {
   isExecutable = true;
   libraryHaskellDepends = [
     aeson annotated-exception base bytestring containers directory
-    ekg-core exceptions filepath generic-lens http-client http-types
-    katip lens lens-aeson monad-control mtl optparse-generic pandoc
-    pipes pipes-concurrency retry servant servant-server stm streamly
-    streamly-core text time transformers-base unliftio
+    ekg-core exceptions filepath generic-lens githash http-client
+    http-types katip lens lens-aeson monad-control mtl optparse-generic
+    pandoc pipes pipes-concurrency retry servant servant-server stm
+    streamly streamly-core text time transformers-base unliftio
     unordered-containers wai warp wreq
   ];
   executableHaskellDepends = [ base ];
   testHaskellDepends = [ base ];
-  license = lib.licenses.bsd3;
+  license = lib.meta.getLicenseFromSpdxId "BSD-3-Clause";
   mainProgram = "wallabag-tagger";
 }

src/Server.hs

@@ -21,6 +21,7 @@ import System.Metrics.Distribution qualified as D
 import UnliftIO (liftIO)
 import UnliftIO.IORef (readIORef)
 import Data.Coerce (coerce)
+import Version (Version, version)
 
 data Health
   = OK
@@ -57,7 +58,8 @@ newtype Metrics = Metrics (HashMap Text SampleValue)
 
 data WallabagRoutes mode = WallabagRoutes
   { _getHealth :: mode :- "health" :> Get '[PlainText, JSON] Health,
-    _getMetrics :: mode :- "metrics" :> Get '[JSON] Metrics
+    _getMetrics :: mode :- "metrics" :> Get '[JSON] Metrics,
+    _getVersion :: mode :- "metrics" :> Get '[JSON] Version
   }
   deriving (Generic)
 
@@ -67,12 +69,16 @@ wallabagServer :: IORef Health -> WallabagRoutes (AsServerT M)
 wallabagServer health =
   WallabagRoutes
     { _getHealth = getHealth health,
-      _getMetrics = getMetrics
+      _getMetrics = getMetrics,
+      _getVersion = getVersion
     }
 
 getHealth :: IORef Health -> M Health
 getHealth = readIORef
 
+getVersion :: M Version
+getVersion = pure version -- Comes from TH during compile time
+
 getMetrics :: M Metrics
 getMetrics = do
   sample <- view metricsStore >>= liftIO . EKG.sampleAll

src/Version.hs

@@ -0,0 +1,34 @@
+{-# LANGUAGE TemplateHaskell #-}
+{-# OPTIONS_GHC -Wno-unrecognised-pragmas #-}
+{-# HLINT ignore "Unused LANGUAGE pragma" #-}
+module Version where
+
+import GitHash (tGitInfoCwd, giHash, giDirty, giCommitDate, giCommitMessage)
+import qualified Data.Aeson as A
+import qualified Data.ByteString.Lazy.Char8 as BL
+import GHC.Generics (Generic)
+
+
+-- Populate the version via the 'githash' package
+data Version = Version
+  { versionCommit :: String
+  , versionDirty :: Bool
+  , versionCommitDate :: String
+  , versionCommitMessage :: String
+  }
+  deriving (Show, Generic)
+
+instance A.ToJSON Version
+
+version :: Version
+version = Version
+  { versionCommit = giHash gi
+  , versionDirty = giDirty gi
+  , versionCommitDate = giCommitDate gi
+  , versionCommitMessage = giCommitMessage gi
+  }
+  where
+    gi = $$tGitInfoCwd
+
+test :: IO ()
+test = BL.putStrLn $ A.encode version

wallabag-tagger.cabal

@@ -27,6 +27,7 @@ library
                       HTTP
                       Server
                       Tracer
+                      Version
     -- other-modules:
     -- other-extensions:
     build-depends:    base ^>=4.18.2.1
@@ -64,6 +65,7 @@ library
                     , generic-lens
                     , optparse-generic
                     , containers
+                    , githash
     hs-source-dirs:   src
     default-language: GHC2021