allow multiple models and avoid translation if not needed

Pipfile

@@ -94,3 +94,6 @@ types-Pygments = "*"
 types-colorama = "*"
 types-psycopg2 = "*"
 types-setuptools = "*"
+
+[translation]
+bergamot = "0.4.5"

src/documents/tasks.py

@@ -13,6 +13,7 @@ from django.conf import settings
 from django.db import transaction
 from django.db.models.signals import post_save
 from filelock import FileLock
+from langdetect import detect
 from whoosh.writing import AsyncWriter
 
 from documents import index
@@ -52,10 +53,21 @@ logger = logging.getLogger("paperless.tasks")
 def translate_content(content):
     import bergamot
 
+    models = settings.TRANSLATION_MODELS.split(",")
+    original_language = detect(content)
+
+    # Avoid translating if we already have the target language
+    if original_language == settings.TRANSLATION_TARGET_LANGUAGE:
+        return ""
+
+    for model in models:
+        # Find the right model for the translation
+        # bergamot models usually end with "tiny" or "base" so we remove that
+        if original_language in model.replace("base", "").replace("tiny", ""):
             service = bergamot.Service(bergamot.ServiceConfig())
 
             model = service.modelFromConfigPath(
-        bergamot.REPOSITORY.modelConfigPath("browsermt", settings.TRANSLATION_MODEL),
+                bergamot.REPOSITORY.modelConfigPath("browsermt", model),
             )
             result = service.translate(
                 model,
@@ -63,6 +75,7 @@ def translate_content(content):
                 bergamot.ResponseOptions(),
             )
             return next(r.target.text for r in result)
+    return ""
 
 
 @shared_task