rails: Add options for database pool size and connection timeout

Improvements:

  * Added new database options

  * Added first test file

README.md

@@ -44,6 +44,12 @@ Module List
      Simple way to configure a whole network of WireGuard machines.
 
 
+Running Tests
+-------------
+
+    $ nix-build test
+
+
 [nixos]: https://nixos.org/
 [nixpkgs]: https://nixos.org/nixpkgs/
 [phoebe]: https://en.wikipedia.org/wiki/Phoebe_(moon)

modules/services/web/rails/database.yml

@@ -1,8 +1,8 @@
 <%= ENV['RAILS_ENV'] %>:
   adapter: postgresql
   encoding: unicode
-  pool: 5
-  timeout: 5000
+  pool: <%= ENV['DATABASE_POOL_SIZE'] %>
+  timeout: <%= ENV['DATABASE_TIMEOUT'] %>
   host: <%= ENV['DATABASE_HOST'] %>
   port: <%= ENV['DATABASE_PORT'] %>
   database: <%= ENV['DATABASE_NAME'] %>

modules/services/web/rails/functions.nix

@@ -21,6 +21,8 @@ rec {
     DATABASE_PORT = toString app.database.port;
     DATABASE_NAME = app.database.name;
     DATABASE_USER = app.database.user;
+    DATABASE_POOL_SIZE = toString app.database.pool;
+    DATABASE_TIMEOUT = toString app.database.timeout;
     DATABASE_PASSWORD_FILE = "${app.home}/state/database.password";
   } // app.environment;
 

modules/services/web/rails/options.nix

@@ -45,10 +45,24 @@ let
       };
 
       port = mkOption {
-        type = types.int;
+        type = types.ints.positive;
         default = config.services.postgresql.port;
         description = "Port number for the database server";
       };
+
+      pool = mkOption {
+        type = types.ints.positive;
+        default = 10;
+        example = 5;
+        description = "Size of connection pool.";
+      };
+
+      timeout = mkOption {
+        type = types.ints.positive;
+        default = 1000;
+        example = 5000;
+        description = "Database timeout in milliseconds.";
+      };
     };
   };
 

modules/services/web/rails/systemd.nix

@@ -74,7 +74,7 @@ let
 
       preStart = optionalString (service.isMain || service.isMigration) ''
         # Link the package into the application's home directory:
-        if [ ! -e "${funcs.appLink app}" ] || [ "${toString app.deployedExternally}" -ne 1 ]; then
+        if [ ! -e "${funcs.appLink app}" ] || [ -z "${toString app.deployedExternally}" ]; then
           ln -nfs "${app.package}" "${funcs.appLink app}"
         fi
 
@@ -82,9 +82,9 @@ let
         rm -rf ${app.home}/config
         mkdir -p ${app.home}/{config,log,tmp,db,state}
         cp -rf ${funcs.appLink app}/share/${app.name}/config.dist/* ${app.home}/config/
-        cp ${funcs.appLink app}/share/${app.name}/db/schema.rb.dist ${app.home}/db/schema.rb
-        cp ${./database.yml} ${app.home}/config/database.yml
-        cp ${app.database.passwordFile} ${app.home}/state/database.password
+        cp -f ${funcs.appLink app}/share/${app.name}/db/schema.rb.dist ${app.home}/db/schema.rb
+        cp -f ${./database.yml} ${app.home}/config/database.yml
+        cp -f ${app.database.passwordFile} ${app.home}/state/database.password
 
         # Additional set up for the home directory:
         mkdir -p ${app.home}/home
@@ -96,7 +96,7 @@ let
 
         # Copy the sourcedFile if necessary:
         ${optionalString (app.sourcedFile != null) ''
-          cp ${app.sourcedFile} ${app.home}/state/sourcedFile.sh
+          cp -f ${app.sourcedFile} ${app.home}/state/sourcedFile.sh
         ''}
 
         # Fix permissions:

test/default.nix

@@ -0,0 +1,8 @@
+{ pkgs ? import <nixpkgs> {}
+}:
+
+with pkgs;
+
+{
+  rails = (callPackage ./services/web/rails/test.nix {}).test;
+}

test/services/web/rails/app/Gemfile

@@ -0,0 +1,2 @@
+source 'https://rubygems.org'
+gem('rake')

test/services/web/rails/app/Gemfile.lock

@@ -0,0 +1,13 @@
+GEM
+  remote: https://rubygems.org/
+  specs:
+    rake (12.3.3)
+
+PLATFORMS
+  ruby
+
+DEPENDENCIES
+  rake
+
+BUNDLED WITH
+   1.17.2

test/services/web/rails/app/README.md

@@ -0,0 +1 @@
+This is a fake Ruby on Rails application for testing.

test/services/web/rails/app/Rakefile

@@ -0,0 +1,19 @@
+# A bunch of dummy rake tasks:
+
+namespace :db do
+  task :migrate do
+    puts "db:migrate"
+  end
+
+  namespace :schema do
+    task :load do
+      puts "db:schema:load"
+    end
+  end
+end
+
+namespace :assets do
+  task :precompile do
+    puts "assets:precompile"
+  end
+end

test/services/web/rails/app/default.nix

@@ -0,0 +1,27 @@
+{ pkgs ? import <nixpkgs> { }
+}:
+
+let
+  phoebe = import ../../../../../helpers.nix { inherit pkgs; };
+
+  puma = pkgs.writeShellScriptBin "puma" ''
+    # Loop forever:
+    while :; do :; done
+  '';
+
+  env = pkgs.bundlerEnv {
+    name = "app-env";
+    ruby = pkgs.ruby;
+    gemfile  = ./Gemfile;
+    lockfile = ./Gemfile.lock;
+    gemset   = ./nix/gemset.nix;
+  };
+
+in
+
+phoebe.mkRailsDerivation {
+  inherit env;
+  name = "app";
+  src = ./.;
+  extraPackages = [ puma ];
+}

test/services/web/rails/app/nix/gemset.nix

@@ -0,0 +1,12 @@
+{
+  rake = {
+    groups = ["default"];
+    platforms = [];
+    source = {
+      remotes = ["https://rubygems.org"];
+      sha256 = "1cvaqarr1m84mhc006g3l1vw7sa5qpkcw0138lsxlf769zdllsgp";
+      type = "gem";
+    };
+    version = "12.3.3";
+  };
+}

test/services/web/rails/test.nix

@@ -0,0 +1,29 @@
+{ pkgs ? import <nixpkgs> {}
+}:
+
+pkgs.nixosTest {
+  name = "rails-test";
+
+  nodes = {
+    simple = {config, pkgs, ...}: {
+      imports = [ ../../../../modules ];
+      phoebe.security.enable = false;
+      phoebe.services.rails.apps.app = {
+        package = import ./app/default.nix { inherit pkgs; };
+        domain = "foo.example.com";
+        port = 3000;
+        database.name = "app";
+        database.user = "app";
+        database.passwordFile = "/dev/null";
+      };
+    };
+  };
+
+
+  testScript = ''
+    $simple->start;
+    $simple->waitForUnit("rails-app-main.service");
+    $simple->succeed("railsdo app rake -T");
+    $simple->succeed("test -L /var/lib/rails/app/package");
+  '';
+}