Migration path Env Var. (#2015)

* changed migrations path to detect an environemnt variable or use default.

* updated docs.

* updated options and migrate.nix.

* fix lifting cs into IO.

* updates to ihp.nix

* recommenting testing flags in ihp.nix

Guide/database-migrations.markdown

@@ -73,6 +73,20 @@ migrate
 
 A good value for `MINIMUM_REVISION` is typically the unix timestamp of the time when the database was initially created.
 
+
+### IHP MIGRATIONS DIR
+
+In production when running the migrations binary it is sometimes convenient to have all your Migrations in a non-standard place:
+e.g. if you need to push migrations onto production server without rebuilding the application. There is an Environment variable
+`IHP_MIGRATION_DIR` to accomplish this.
+
+```
+IHP_MIGRATION_DIR=path/to/my/migration/dir
+```
+
+This can be set in the environment attribute set of your IHP app flake.
+
+
 ## Common Issues
 
 ### ALTER TYPE ... ADD cannot run inside a transaction block

IHP/SchemaMigration.hs

@@ -12,6 +12,7 @@ import qualified Data.Text.IO as Text
 import IHP.ModelSupport hiding (withTransaction)
 import qualified Data.Char as Char
 import IHP.Log.Types
+import IHP.EnvVar
 
 data Migration = Migration
     { revision :: Int
@@ -37,7 +38,9 @@ migrate options = do
 -- All queries are executed inside a database transaction to make sure that it can be restored when something goes wrong.
 runMigration :: (?modelContext :: ModelContext) => Migration -> IO ()
 runMigration migration@Migration { revision, migrationFile } = do
-    migrationSql <- Text.readFile (cs $ migrationPath migration)
+    -- | User can specify migrations directory as environment variable (defaults to /Application/Migrations/...)
+    migrationFilePath <- migrationPath migration
+    migrationSql <- Text.readFile (cs migrationFilePath)
 
     let fullSql = [trimming|
         BEGIN;
@@ -123,5 +126,7 @@ pathToMigration fileName = case revision of
                 |> fmap textToInt
                 |> join
 
-migrationPath :: Migration -> Text
-migrationPath Migration { migrationFile } = "Application/Migration/" <> migrationFile
+migrationPath :: Migration -> IO Text
+migrationPath Migration { migrationFile } = do
+    migrationDir <- envOrDefault "IHP_MIGRATION_DIR" "Application/Migration/"
+    pure (migrationDir <> migrationFile)

NixSupport/nixosModules/options.nix

@@ -13,63 +13,70 @@ with lib;
             type = types.str;
             default = "https://${config.services.ihp.domain}";
         };
-        
+
         migrations = mkOption {
             type = types.path;
         };
-        
+
         schema = mkOption {
             type = types.path;
         };
-        
+
         fixtures = mkOption {
             type = types.path;
         };
-        
+
         httpsEnabled = mkOption {
             type = types.bool;
             default = true;
         };
-        
+
         databaseName = mkOption {
             type = types.str;
             default = "app";
         };
-        
+
         databaseUser = mkOption {
             type = types.str;
             default = "ihp";
         };
-        
+
         databaseUrl = mkOption {
             type = types.str;
         };
-        
+
         # https://ihp.digitallyinduced.com/Guide/database-migrations.html#skipping-old-migrations
         minimumRevision = mkOption {
             type = types.int;
             default = 0;
         };
-
+
+        # https://ihp.digitallyinduced.com/Guide/database-migrations.html#ihp-migrations-dir
+        ihpMigrationDir = mkOption {
+            type = types.str;
+            default = "Application/Migration/";
+        };
+
+
         ihpEnv = mkOption {
             type = types.str;
             default = "Production";
         };
-        
+
         appPort = mkOption {
             type = types.int;
             default = 8000;
         };
-        
+
         requestLoggerIPAddrSource = mkOption {
             type = types.str;
             default = "FromHeader";
         };
-        
+
         sessionSecret = mkOption {
             type = types.str;
         };
-        
+
         additionalEnvVars = mkOption {
             type = types.attrs;
             default = {};
@@ -79,7 +86,7 @@ with lib;
             type = types.package;
             default = if config.services.ihp.optimized then self.packages."${pkgs.system}".optimized-prod-server else self.packages."${pkgs.system}".default;
         };
-        
+
         optimized = mkOption {
             type = types.bool;
             default = false;
@@ -91,4 +98,3 @@ with lib;
         };
     };
 }
-

NixSupport/nixosModules/services/migrate.nix

@@ -22,6 +22,7 @@ in
             environment = {
                 DATABASE_URL = cfg.databaseUrl;
                 MINIMUM_REVISION = "${toString cfg.minimumRevision}";
+                IHP_MIGRATION_DIR = cfg.ihpMigrationDir;
             };
     };
-}
+}

ihp-ide/IHP/IDE/SchemaDesigner/Controller/Migrations.hs

@@ -61,7 +61,7 @@ instance Controller MigrationsController where
                         let errorMessage = case fromException exception of
                                 Just (exception :: EnhancedSqlError) -> cs exception.sqlError.sqlErrorMsg
                                 Nothing -> tshow exception
-                        
+
                         setErrorMessage errorMessage
                         redirectTo MigrationsAction
                     Right _ -> do
@@ -79,14 +79,14 @@ instance Controller MigrationsController where
     action UpdateMigrationAction { migrationId } = do
         migration <- findMigrationByRevision migrationId
         let sqlStatements = param "sqlStatements"
-
-        Text.writeFile (cs $ SchemaMigration.migrationPath migration) sqlStatements
+        migrationFilePath <- SchemaMigration.migrationPath migration
+        Text.writeFile (cs migrationFilePath) sqlStatements
 
         redirectTo MigrationsAction
 
     action DeleteMigrationAction { migrationId } = do
         migration <- findMigrationByRevision migrationId
-        let path = cs $ SchemaMigration.migrationPath migration
+        path <- cs <$> SchemaMigration.migrationPath migration
 
         Directory.removeFile path
 
@@ -101,15 +101,17 @@ instance Controller MigrationsController where
                 let errorMessage = case fromException exception of
                         Just (exception :: EnhancedSqlError) -> cs exception.sqlError.sqlErrorMsg
                         Nothing -> tshow exception
-                
+
                 setErrorMessage errorMessage
                 redirectTo MigrationsAction
             Right _ -> do
                 clearDatabaseNeedsMigration
                 redirectTo MigrationsAction
 
 readSqlStatements :: SchemaMigration.Migration -> IO Text
-readSqlStatements migration = Text.readFile (cs $ SchemaMigration.migrationPath migration)
+readSqlStatements migration = do
+    migrationFilePath <- (SchemaMigration.migrationPath migration)
+    pure Text.readFile (migrationFilePath)
 
 findRecentMigrations :: IO [SchemaMigration.Migration]
 findRecentMigrations = take 20 . reverse <$> SchemaMigration.findAllMigrations