Update Document model to use background image conversion task

mayan/apps/documents/models.py

@@ -24,6 +24,7 @@ from converter.api import (convert, get_page_count,
 from converter.exceptions import UnknownFileFormat
 from converter.literals import (DEFAULT_ZOOM_LEVEL, DEFAULT_ROTATION,
                                 DEFAULT_PAGE_NUMBER)
+from converter.tasks import task_convert
 from mimetype.api import get_mimetype
 
 from .exceptions import NewDocumentVersionNotAllowed
@@ -37,9 +38,8 @@ from .settings import (CACHE_PATH, CHECKSUM_FUNCTION, DISPLAY_SIZE,
                        UUID_FUNCTION, ZOOM_MAX_LEVEL, ZOOM_MIN_LEVEL)
 from .utils import document_save_to_temp_dir
 
-# document image cache name hash function
-HASH_FUNCTION = lambda x: hashlib.sha256(x).hexdigest()
-
+CONVERTER_TASK_TIMEOUT = 2  # In seconds
+HASH_FUNCTION = lambda x: hashlib.sha256(x).hexdigest()  # document image cache name hash function
 logger = logging.getLogger(__name__)
 
 
@@ -134,7 +134,8 @@ class Document(models.Model):
 
         logger.debug('image_cache_name: %s' % image_cache_name)
 
-        return convert(image_cache_name, cleanup_files=False, size=size, zoom=zoom, rotation=rotation)
+        task = task_convert.delay(image_cache_name, cleanup_files=False, size=size, zoom=zoom, rotation=rotation)
+        return task.get(timeout=CONVERTER_TASK_TIMEOUT)
 
     def get_image(self, size=DISPLAY_SIZE, page=DEFAULT_PAGE_NUMBER, zoom=DEFAULT_ZOOM_LEVEL, rotation=DEFAULT_ROTATION, as_base64=False, version=None):
         if zoom < ZOOM_MIN_LEVEL: