Make download work in different formats

Signed-off-by: Michal Čihař <michal@cihar.com>

weblate/api/tests.py

@@ -116,3 +116,16 @@ class TranslationAPITest(APIBaseTest):
         self.assertContains(
             response, 'Project-Id-Version: Weblate Hello World 2012'
         )
+
+    def test_download_format(self):
+        args = {'format': 'xliff'}
+        args.update(self.translation_kwargs)
+        response = self.client.get(
+            reverse(
+                'api:translation-download',
+                kwargs=args
+            )
+        )
+        self.assertContains(
+            response, '<xliff'
+        )

weblate/api/views.py

@@ -19,6 +19,7 @@
 #
 
 from django.shortcuts import get_object_or_404
+from django.http import Http404
 
 from rest_framework import viewsets
 from rest_framework.decorators import detail_route
@@ -27,6 +28,7 @@ from weblate.api.serializers import (
     ProjectSerializer, ComponentSerializer, TranslationSerializer,
     LanguageSerializer,
 )
+from weblate.trans.exporters import EXPORTERS
 from weblate.trans.models import Project, SubProject, Translation
 from weblate.lang.models import Language
 from weblate.trans.views.helper import download_translation_file
@@ -50,6 +52,25 @@ class MultipleFieldMixin(object):
         return get_object_or_404(queryset, **lookup)
 
 
+class RawFileMixin(object):
+    """
+    Allows to skip content negotiation for certain requests.
+    """
+    raw_urls = ()
+
+    def perform_content_negotiation(self, request, force=False):
+        """Custom content negotiation"""
+        if request.resolver_match.url_name in self.raw_urls:
+            fmt = self.format_kwarg or request.query_params.get('format')
+            if fmt is None or fmt in EXPORTERS:
+                renderers = self.get_renderers()
+                return (renderers[0], renderers[0].media_type)
+            raise Http404('Not supported exporter')
+        return super(TranslationViewSet, self).perform_content_negotiation(
+            request, force
+        )
+
+
 class ProjectViewSet(viewsets.ReadOnlyModelViewSet):
     """Translation projects API.
     """
@@ -84,7 +105,7 @@ class ComponentViewSet(MultipleFieldMixin, viewsets.ReadOnlyModelViewSet):
         )
 
 
-class TranslationViewSet(MultipleFieldMixin, viewsets.ReadOnlyModelViewSet):
+class TranslationViewSet(RawFileMixin, MultipleFieldMixin, viewsets.ReadOnlyModelViewSet):
     """Translation components API.
     """
     queryset = Translation.objects.none()
@@ -92,6 +113,9 @@ class TranslationViewSet(MultipleFieldMixin, viewsets.ReadOnlyModelViewSet):
     lookup_fields = (
         'subproject__project__slug', 'subproject__slug', 'language__code',
     )
+    raw_urls = (
+        'translation-download',
+    )
 
     def get_queryset(self):
         acl_projects, filtered = Project.objects.get_acl_status(
@@ -116,9 +140,7 @@ class TranslationViewSet(MultipleFieldMixin, viewsets.ReadOnlyModelViewSet):
     @detail_route(methods=['get'])
     def download(self, request, **kwargs):
         obj = self.get_object()
-        fmt = None
-        if 'format' in request.GET:
-            fmt = request.GET['format']
+        fmt = self.format_kwarg or request.query_params.get('format')
         return download_translation_file(obj, fmt)