Add Bulgarian language support (#13147)

### What problem does this PR solve?

RAGFlow supports 12 UI languages but does not include Bulgarian. This PR
adds Bulgarian (`bg` / `Български`) as the 13th supported language,
covering the full UI translation (2001 keys across all 26 sections) and
OCR/PDF parser language mapping.

### Type of change

- [x] New Feature (non-breaking change which adds functionality)

### Changes

- **`web/src/constants/common.ts`** — Registered Bulgarian in all 5
language data structures (`LanguageList`, `LanguageMap`,
`LanguageAbbreviation` enum, `LanguageAbbreviationMap`,
`LanguageTranslationMap`)
- **`web/src/locales/config.ts`** — Added lazy-loading dynamic import
for the `bg` locale
- **`web/src/locales/bg.ts`** *(new)* — Full Bulgarian translation file
with all 26 sections, matching the English source (`en.ts`). All
interpolation placeholders, HTML tags, and technical terms are preserved
as-is
- **`deepdoc/parser/mineru_parser.py`** — Mapped `'Bulgarian'` to
`'cyrillic'` in `LANGUAGE_TO_MINERU_MAP` for OCR/PDF parser support

### How it works

The language selector automatically picks up the new entry. When a user
selects "Български", the translation bundle is lazy-loaded on demand.
The preference is persisted to the database and localStorage across
sessions.

deepdoc/parser/mineru_parser.py

@@ -73,6 +73,7 @@ LANGUAGE_TO_MINERU_MAP = {
     'Thai': 'th',
     'Greek': 'el',
     'Hindi': 'devanagari',
+    'Bulgarian': 'cyrillic',
 }
 
 

web/src/constants/common.ts

@@ -54,6 +54,7 @@ export const LanguageList = [
   'German',
   'French',
   'Italian',
+  'Bulgarian',
 ];
 export const LanguageMap = {
   English: 'English',
@@ -68,6 +69,7 @@ export const LanguageMap = {
   German: 'German',
   French: 'Français',
   Italian: 'Italiano',
+  Bulgarian: 'Български',
 };
 
 export enum LanguageAbbreviation {
@@ -83,6 +85,7 @@ export enum LanguageAbbreviation {
   De = 'de',
   Fr = 'fr',
   It = 'it',
+  Bg = 'bg',
 }
 
 export const LanguageAbbreviationMap = {
@@ -98,6 +101,7 @@ export const LanguageAbbreviationMap = {
   [LanguageAbbreviation.De]: 'Deutsch',
   [LanguageAbbreviation.Fr]: 'Français',
   [LanguageAbbreviation.It]: 'Italiano',
+  [LanguageAbbreviation.Bg]: 'Български',
 };
 
 export const LanguageTranslationMap = {
@@ -121,6 +125,7 @@ export const LanguageTranslationMap = {
   Greek: 'el',
   Hindi: 'hi',
   Ukrainian: 'uk',
+  Bulgarian: 'bg',
 };
 
 export enum FileMimeType {

web/src/locales/BULGARIAN_LANGUAGE_CHANGES.md

@@ -0,0 +1,54 @@
+# Add Bulgarian Language Support
+
+**Repository:** https://github.com/trifonnt/ragflow
+
+## Overview
+
+Added Bulgarian (`bg` / `Български`) as the 13th supported UI language in RAGFlow.
+
+## Changed Files
+
+### `web/src/constants/common.ts`
+
+Registered Bulgarian in all 5 language data structures:
+
+- **`LanguageList`** — Added `'Bulgarian'` to the array of available languages
+- **`LanguageMap`** — Added `Bulgarian: 'Български'` mapping English name to native name
+- **`LanguageAbbreviation`** enum — Added `Bg = 'bg'` using ISO 639-1 code
+- **`LanguageAbbreviationMap`** — Added `[LanguageAbbreviation.Bg]: 'Български'` for the language selector display
+- **`LanguageTranslationMap`** — Added `Bulgarian: 'bg'` for language code resolution
+
+### `web/src/locales/config.ts`
+
+Added a lazy-loading dynamic import entry for the Bulgarian locale file:
+
+```typescript
+[LanguageAbbreviation.Bg]: () => import('./bg'),
+```
+
+This ensures the Bulgarian translation bundle is only loaded on demand when a user selects it.
+
+### `web/src/locales/bg.ts` (new file)
+
+Created the full Bulgarian translation file containing all 26 sections and 2001 translation keys, matching the English source (`en.ts`) exactly:
+
+`common`, `login`, `header`, `memories`, `memory`, `knowledgeList`, `knowledgeDetails`, `knowledgeConfiguration`, `chunk`, `chat`, `setting`, `message`, `fileManager`, `flow`, `llmTools`, `modal`, `mcp`, `search`, `language`, `pagination`, `dataflowParser`, `datasetOverview`, `deleteModal`, `empty`, `admin`, `explore`
+
+All interpolation placeholders (`{{variable}}`), HTML tags, and technical terms (model names, URLs, API references) are preserved as-is.
+
+### `deepdoc/parser/mineru_parser.py`
+
+Added Bulgarian to the `LANGUAGE_TO_MINERU_MAP` dictionary for OCR/PDF parser language support:
+
+```python
+'Bulgarian': 'cyrillic',
+```
+
+Bulgarian uses the Cyrillic script, so the `'cyrillic'` MinerU language code is used.
+
+## How It Works
+
+- The language selector in the header automatically picks up the new entry from `LanguageList` and `LanguageMap`
+- When a user selects "Български", `changeLanguageAsync('bg')` lazy-loads `bg.ts` and switches the UI
+- The user's preference is saved to the database and localStorage for persistence across sessions
+- `supportedLngs` in i18next is derived from `Object.values(LanguageAbbreviation)`, so adding `Bg` to the enum automatically registers it

web/src/locales/config.ts

@@ -19,6 +19,7 @@ const languageImports: Record<string, () => Promise<{ default: any }>> = {
   [LanguageAbbreviation.De]: () => import('./de'),
   [LanguageAbbreviation.Fr]: () => import('./fr'),
   [LanguageAbbreviation.It]: () => import('./it'),
+  [LanguageAbbreviation.Bg]: () => import('./bg'),
 };
 
 const enFlattened = flattenObject(translation_en);

web/src/locales/de.ts

@@ -28,6 +28,7 @@ export default {
       chinese: 'Vereinfachtes Chinesisch',
       traditionalChinese: 'Traditionelles Chinesisch',
       russian: 'Russisch',
+      bulgarian: 'Bulgarisch',
       german: 'Deutsch',
       language: 'Sprache',
       languageMessage: 'Bitte geben Sie Ihre Sprache ein!',
@@ -2388,6 +2389,7 @@ Wichtige strukturierte Informationen können sein: Namen, Daten, Orte, Ereigniss
       korean: 'Koreanisch',
       vietnamese: 'Vietnamesisch',
       russian: 'Russisch',
+      bulgarian: 'Bulgarisch',
     },
     pagination: {
       total: 'Gesamt {{total}}',

web/src/locales/en.ts

@@ -27,6 +27,7 @@ export default {
       chinese: 'Simplified Chinese',
       traditionalChinese: 'Traditional Chinese',
       russian: 'Russian',
+      bulgarian: 'Bulgarian',
       language: 'Language',
       languageMessage: 'Please input your language!',
       languagePlaceholder: 'select your language',
@@ -2363,6 +2364,7 @@ Important structured information may include: names, dates, locations, events, k
       korean: 'Korean',
       vietnamese: 'Vietnamese',
       russian: 'Russian',
+      bulgarian: 'Bulgarian',
     },
     pagination: {
       total: 'Total {{total}}',

web/src/locales/es.ts

@@ -19,6 +19,7 @@ export default {
       portugueseBr: 'Portugués (Brasil)',
       chinese: 'Chino simplificado',
       traditionalChinese: 'Chino tradicional',
+      bulgarian: 'Búlgaro',
       language: 'Idioma',
       languageMessage: '¡Por favor ingresa tu idioma!',
       languagePlaceholder: 'Selecciona tu idioma',

web/src/locales/fr.ts

@@ -19,6 +19,7 @@ export default {
       portugueseBr: 'Portugais (Brésil)',
       chinese: 'Chinois simplifié',
       traditionalChinese: 'Chinois traditionnel',
+      bulgarian: 'Bulgare',
       language: 'Langue',
       languageMessage: 'Veuillez saisir votre langue !',
       languagePlaceholder: 'Sélectionnez votre langue',

web/src/locales/id.ts

@@ -19,6 +19,7 @@ export default {
       portugueseBr: 'Portugis (Brasil)',
       chinese: 'Cina',
       traditionalChinese: 'Cina Tradisional',
+      bulgarian: 'Bulgaria',
       language: 'Bahasa',
       languageMessage: 'Silakan masukkan bahasa Anda!',
       languagePlaceholder: 'Pilih bahasa Anda',

web/src/locales/it.ts

@@ -27,6 +27,7 @@ export default {
       chinese: 'Cinese semplificato',
       traditionalChinese: 'Cinese tradizionale',
       russian: 'Russo',
+      bulgarian: 'Bulgaro',
       italian: 'Italiano',
       german: 'Tedesco',
       french: 'Francese',
@@ -1190,6 +1191,7 @@ Quanto sopra è il contenuto che devi riassumere.`,
       korean: 'Coreano',
       vietnamese: 'Vietnamita',
       russian: 'Russo',
+      bulgarian: 'Bulgaro',
     },
     pagination: {
       total: 'Totale {{total}}',

web/src/locales/ja.ts

@@ -19,6 +19,7 @@ export default {
       portugueseBr: 'ポルトガル語 (ブラジル)',
       chinese: '中国語（簡体字）',
       traditionalChinese: '中国語（繁体字）',
+      bulgarian: 'ブルガリア語',
       language: '言語',
       languageMessage: 'あなたの言語を入力してください！',
       languagePlaceholder: 'あなたの言語を選択してください',

web/src/locales/pt-br.ts

@@ -18,6 +18,7 @@ export default {
       portugueseBr: 'Português (Brasil)',
       chinese: 'Chinês Simplificado',
       traditionalChinese: 'Chinês Tradicional',
+      bulgarian: 'Búlgaro',
       language: 'Idioma',
       languageMessage: 'Por favor, insira seu idioma!',
       languagePlaceholder: 'selecione seu idioma',

web/src/locales/ru.ts

@@ -26,6 +26,7 @@ export default {
       chinese: 'Китайский упрощенный',
       traditionalChinese: 'Китайский традиционный',
       russian: 'Русский',
+      bulgarian: 'Болгарский',
       language: 'Язык',
       languageMessage: 'Пожалуйста, укажите ваш язык!',
       languagePlaceholder: 'выберите ваш язык',
@@ -2036,6 +2037,7 @@ export default {
       korean: 'Корейский',
       vietnamese: 'Вьетнамский',
       russian: 'Русский',
+      bulgarian: 'Болгарский',
     },
     pagination: {
       total: 'Всего {{total}}',

web/src/locales/vi.ts

@@ -18,6 +18,7 @@ export default {
       portugueseBr: 'Tiếng Bồ Đào Nha (Brazil)',
       chinese: 'Tiếng Trung giản thể',
       traditionalChinese: 'Tiếng Trung phồn thể',
+      bulgarian: 'Tiếng Bulgaria',
       language: 'Ngôn ngữ',
       languageMessage: 'Vui lòng chọn ngôn ngữ của bạn!',
       languagePlaceholder: 'chọn ngôn ngữ của bạn',

web/src/locales/zh-traditional.ts

@@ -18,6 +18,7 @@ export default {
       portugueseBr: '葡萄牙語 (巴西)',
       chinese: '簡體中文',
       traditionalChinese: '繁體中文',
+      bulgarian: '保加利亞語',
       language: '語言',
       languageMessage: '請輸入語言',
       languagePlaceholder: '請選擇語言',

web/src/locales/zh.ts

@@ -26,6 +26,7 @@ export default {
       portugueseBr: '葡萄牙语 (巴西)',
       chinese: '简体中文',
       traditionalChinese: '繁体中文',
+      bulgarian: '保加利亚语',
       language: '语言',
       languageMessage: '请输入语言',
       languagePlaceholder: '请选择语言',
@@ -2107,6 +2108,7 @@ Tokenizer 会根据所选方式将内容存储为对应的数据结构。`,
       japanese: '日语',
       korean: '韩语',
       vietnamese: '越南语',
+      bulgarian: '保加利亚语',
     },
     pagination: {
       total: '总共 {{total}} 条',