Specify a locale

main.rb

@@ -22,7 +22,7 @@ before do
 end
 
 get '/words/:id' do
-  Context.call db_pool: $DB_POOL, user_lang_id: 2 do |context|
+  Context.call db_pool: $DB_POOL, locale: params[:locale] do |context|
     word_id = Integer params[:id]
 
     word_info = context.word_info(word_id)
@@ -45,30 +45,40 @@ class Context
     new(**kwargs).send :call, db_pool: db_pool, &block
   end
 
-  def initialize(user_lang_id:)
-    self.user_lang_id = user_lang_id
+  def initialize(locale:)
+    self.locale = locale
   end
 
 private
 
-  attr_reader :user_lang_id
+  attr_reader :locale, :locale_id
 
   def call(db_pool:)
     db_pool.with do |db_conn|
+      @locale_id = db_conn.exec_params(
+        (
+          <<~SQL
+            SELECT id
+            FROM languages
+            WHERE code = $1
+            ORDER BY
+              (CASE WHEN code != 'en' THEN 1 ELSE 2 END) ASC
+            LIMIT 1
+          SQL
+        ),
+        [locale],
+      ).values.first&.first
+
       @db_conn = db_conn
       result = yield self
       @db_conn = nil
+
       result
     end
   end
 
-  def user_lang_id=(user_lang_id)
-    return @user_lang_id = nil if user_lang_id.nil?
-
-    user_lang_id = Integer user_lang_id
-    raise unless user_lang_id.positive?
-
-    @user_lang_id = user_lang_id
+  def locale=(locale)
+    @locale = String(locale).strip.freeze
   end
 
 public
@@ -121,7 +131,7 @@ public
           LIMIT 1
         SQL
       ),
-      [word_id, user_lang_id],
+      [word_id, locale_id],
     ).values.first&.first
 
     str = String(column).strip.freeze
@@ -149,7 +159,7 @@ public
           ORDER BY translations.index ASC
         SQL
       ),
-      [word_id, user_lang_id],
+      [word_id, locale_id],
     ).to_a
 
     values.map.with_index do |row, index|