Dev Server now ensure that build/ihp-lib exists

IHP/FrameworkConfig.hs

@@ -219,27 +219,6 @@ defaultDatabaseUrl = do
     let defaultDatabaseUrl = "postgresql:///app?host=" <> cs currentDirectory <> "/build/db"
     (Environment.lookupEnv "DATABASE_URL") >>= (pure . maybe defaultDatabaseUrl cs )
 
--- | Finds the lib
---
--- The location depends on whether the framework is installed through nix
--- or checked out from git inside the current project directory.
---
--- When it's installed with nix, the lib dir is located at @lib/ihp@
--- while the dev server binary is located at @bin/RunDevServer@.
-findLibDirectory :: IO Text
-findLibDirectory = do
-    frameworkMountedLocally <- Directory.doesDirectoryExist "IHP"
-    ihpLibSymlinkAvailable <- Directory.doesDirectoryExist "build/ihp-lib"
-    if frameworkMountedLocally
-        then pure "IHP/lib/IHP/"
-        else if ihpLibSymlinkAvailable
-            then do
-                pure "build/ihp-lib/"
-            else do
-                binDir <- cs <$> Process.readCreateProcess (Process.shell "dirname $(which RunDevServer)") ""
-                pure (Text.strip binDir <> "/../lib/IHP/")
-
-
 -- Returns 'True' when the application is running in a given environment
 isEnvironment :: (?context :: context, ConfigProvider context) => Environment -> Bool
 isEnvironment environment = (getFrameworkConfig ?context |> get #environment) == environment

IHP/IDE/ToolServer.hs

@@ -50,6 +50,7 @@ import qualified IHP.AutoRefresh.Types as AutoRefresh
 import IHP.Controller.Context
 import qualified IHP.IDE.ToolServer.Layout as Layout
 import IHP.Controller.Layout
+import qualified IHP.LibDir as LibDir
 
 startToolServer :: (?context :: Context) => IO ()
 startToolServer = do
@@ -83,7 +84,7 @@ startToolServer' port isDebugMode = do
             let ?context = requestContext
             frontControllerToWAIApp toolServerApplication ErrorController.handleNotFound
 
-    libDirectory <- cs <$> Config.findLibDirectory
+    libDirectory <- cs <$> LibDir.findLibDirectory
     let staticMiddleware :: Wai.Middleware = staticPolicy (addBase (libDirectory <> "static/"))
 
     let openAppUrl = openUrl ("http://localhost:" <> tshow port <> "/")

IHP/LibDir.hs

@@ -0,0 +1,55 @@
+{-|
+Module: IHP.LibDir
+Description: Functions to access the IHP lib/ directory at runtime
+Copyright: (c) digitally induced GmbH, 2020
+-}
+module IHP.LibDir (findLibDirectory, ensureSymlink) where
+
+import IHP.Prelude
+import qualified System.Directory as Directory
+import qualified Data.Text as Text
+import qualified System.Process as Process
+import qualified System.Posix.Files as Files
+
+-- | Finds the lib
+--
+-- The location depends on whether the framework is installed through nix
+-- or checked out from git inside the current project directory.
+--
+-- When it's installed with nix, the lib dir is located at @lib/ihp@
+-- while the dev server binary is located at @bin/RunDevServer@.
+findLibDirectory :: IO Text
+findLibDirectory = do
+    frameworkMountedLocally <- Directory.doesDirectoryExist "IHP"
+    ihpLibSymlinkAvailable <- Directory.doesDirectoryExist "build/ihp-lib"
+    if frameworkMountedLocally
+        then pure "IHP/lib/IHP/"
+        else if ihpLibSymlinkAvailable
+            then do
+                pure "build/ihp-lib/"
+            else do
+                binDir <- cs <$> Process.readCreateProcess (Process.shell "dirname $(which RunDevServer)") ""
+                pure (Text.strip binDir <> "/../lib/IHP/")
+
+-- | Creates the build/ihp-lib symlink if missing
+--
+-- This is called in dev mode to make sure that build/ihp-lib points to the right IHP version.
+-- Otherwise the CLI tools might not work as expected, e.g. @make db@ might fail.
+--
+-- If the symlink is missing, it tries to fix this by starting a new nix-shell and pinpointing the framework lib dir in there
+ensureSymlink :: IO ()
+ensureSymlink = do
+    frameworkMountedLocally <- pure False
+    ihpLibSymlinkAvailable <- Directory.doesDirectoryExist "build/ihp-lib"
+
+    unless ihpLibSymlinkAvailable do
+        -- Make sure the build directory exists, otherwise we cannot add the symlink
+        Directory.createDirectoryIfMissing False "build"
+
+        libDir <- if frameworkMountedLocally
+            then pure "../IHP/lib/IHP/"
+            else do
+                putStrLn "Building build/ihp-lib. This might take a few seconds"
+                binDir <- cs <$> Process.readCreateProcess (Process.shell "nix-shell --run 'dirname $(which RunDevServer)'") ""
+                pure (Text.strip binDir <> "/../lib/IHP/")
+        Files.createSymbolicLink (cs libDir) "build/ihp-lib"

IHP/Server.hs

@@ -28,6 +28,7 @@ import qualified Control.Concurrent as Concurrent
 import qualified IHP.AutoRefresh as AutoRefresh
 import qualified IHP.AutoRefresh.Types as AutoRefresh
 import qualified IHP.WebSocket as WS
+import IHP.LibDir
 
 run :: (FrontController RootApplication) => ConfigBuilder -> IO ()
 run configBuilder = do

exe/IHP/IDE/DevServer.hs

@@ -21,12 +21,14 @@ import System.Info
 import Data.String.Conversions (cs)
 import qualified IHP.FrameworkConfig as Config
 import IHP.Environment
+import qualified IHP.LibDir as LibDir
 
 main :: IO ()
 main = do
     actionVar <- newEmptyMVar
     appStateRef <- newIORef emptyAppState
     portConfig <- findAvailablePortConfig
+    LibDir.ensureSymlink
 
     -- Start the dev server in Debug mode by setting the env var DEBUG=1
     -- Like: $ DEBUG=1 ./start
@@ -230,7 +232,7 @@ startAppGHCI = do
 
     let ManagedProcess { outputHandle, errorHandle } = process
 
-    libDirectory <- Config.findLibDirectory
+    libDirectory <- LibDir.findLibDirectory
 
     let loadAppCommands = 
             [ ":script " <> cs libDirectory <> "/applicationGhciConfig"

ihp.cabal

@@ -247,6 +247,7 @@ library IHPFramework
         , IHP.FlashMessages.ControllerFunctions
         , IHP.FlashMessages.ViewFunctions
         , IHP.SchemaMigration
+        , IHP.LibDir
 
 executable RunDevServer
     import: shared-properties