Finish refactor of the new compressed file class support. Closes GitLab issue #7.

Signed-off-by: Roberto Rosario <roberto.rosario.gonzalez@gmail.com>

HISTORY.rst

@@ -127,6 +127,8 @@
 - Remove usage of pace.js. Would cause XMLRequest to fallback to
   synchronous mode.
 - Add custom AJAX spinner.
+- Complete refactor of the compress archive class support. Closes
+  GitLab issue #7.
 
 3.0.3 (2018-08-17)
 ==================

docs/releases/3.1.rst

@@ -424,6 +424,7 @@ must be changed::
 Bugs fixed or issues closed
 ===========================
 
+* `GitLab issue #7 <https://gitlab.com/mayan-edms/mayan-edms/issues/7>`_ Feature: other compressors than zip for compressed documents
 * `GitLab issue #259 <https://gitlab.com/mayan-edms/mayan-edms/issues/259>`_ Thumbnails: why are they created on the fly (therefore: not cached)
 
 .. _PyPI: https://pypi.python.org/pypi/mayan-edms/

mayan/apps/common/compressed_files.py

@@ -1,6 +1,7 @@
 from __future__ import unicode_literals
 
 from io import BytesIO
+import tarfile
 import zipfile
 
 try:
@@ -11,98 +12,154 @@ except ImportError:
 
 from django.core.files.uploadedfile import SimpleUploadedFile
 
+from mimetype.api import get_mimetype
 
-class NotACompressedFile(Exception):
-    pass
+from .exceptions import NoMIMETypeMatch
 
 
-class CompressedFile(object):
-    def __init__(self, file_input=None):
-        if file_input:
-            try:
-                # Is it a file like object?
-                file_input.seek(0)
-            except AttributeError:
-                # If not, try open it.
-                self._open(file_input)
-            else:
-                self.file_object = file_input
-        else:
-            self._create()
+class Archive(object):
+    _registry = {}
 
-    def _create(self):
-        self.descriptor = BytesIO()
-        self.zf = zipfile.ZipFile(self.descriptor, mode='w')
+    @classmethod
+    def register(cls, mime_types, archive_classes):
+        for mime_type in mime_types:
+            for archive_class in archive_classes:
+                cls._registry.setdefault(
+                    mime_type, []
+                ).append(archive_class)
 
-    def _open(self, file_input):
-        try:
-            # Is it a file like object?
-            file_input.seek(0)
-        except AttributeError:
-            # If not, try open it.
-            self.descriptor = open(file_input, 'r+b')
-        else:
-            self.descriptor = file_input
+    @classmethod
+    def open(cls, file_object):
+        mime_type = get_mimetype(
+            file_object=file_object, mimetype_only=True
+        )[0]
 
         try:
-            test = zipfile.ZipFile(self.descriptor, mode='r')
-        except zipfile.BadZipfile:
-            raise NotACompressedFile
-        else:
-            test.close()
-            self.descriptor.seek(0)
-            self.zf = zipfile.ZipFile(self.descriptor, mode='a')
+            for archive_class in cls._registry[mime_type]:
+                instance = archive_class()
+                instance._open(file_object=file_object)
+                return instance
+        except KeyError:
+            raise NoMIMETypeMatch
 
-    def add_file(self, file_input, arcname=None):
-        try:
-            # Is it a file like object?
-            file_input.seek(0)
-        except AttributeError:
-            # If not, keep it
-            self.zf.write(
-                file_input, arcname=arcname, compress_type=COMPRESSION
-            )
-        else:
-            self.zf.writestr(arcname, file_input.read())
+    def _open(self, file_object):
+        raise NotImplementedError
 
-    def contents(self):
+    def add_file(self, file_object, filename):
+        """
+        Add a file as a member of an archive
+        """
+        raise NotImplementedError
+
+    def close(self):
+        self._archive.close()
+
+    def create(self):
+        """
+        Create an empty archive
+        """
+        raise NotImplementedError
+
+    def get_members(self):
+        return (
+            SimpleUploadedFile(
+                name=filename, content=self.member_contents(filename)
+            ) for filename in self.members()
+        )
+
+    def member_contents(self, filename):
+        """
+        Return the content of a member
+        """
+        raise NotImplementedError
+
+    def members(self):
+        """
+        Return a list of all the elements inside the archive
+        """
+        raise NotImplementedError
+
+    def open_member(self, filename):
+        """
+        Return a file-like object to a member of the archive
+        """
+        raise NotImplemented
+
+
+class TarArchive(Archive):
+    def _open(self, file_object):
+        self._archive = tarfile.open(fileobj=file_object)
+
+    def add_file(self, file_object, filename):
+        self._archive.addfile(
+            tarfile.TarInfo(), fileobj=file_object
+        )
+
+    def create(self):
+        self.string_buffer = BytesIO()
+        self._archive = tarfile.TarFile(fileobj=self.string_buffer, mode='w')
+
+    def member_contents(self, filename):
+        return self._archive.extractfile(filename).read()
+
+    def members(self):
+        return self._archive.getnames()
+
+    def open_member(self, filename):
+        return self._archive.extractfile(filename)
+
+
+class ZipArchive(Archive):
+    def _open(self, file_object):
+        self._archive = zipfile.ZipFile(file_object)
+
+    def add_file(self, file_object, filename):
+        self._archive.writestr(
+            zinfo_or_arcname=filename, bytes=file_object.read(),
+            compress_type=COMPRESSION
+        )
+
+    def create(self):
+        self.string_buffer = BytesIO()
+        self._archive = zipfile.ZipFile(self.string_buffer, mode='w')
+
+    def member_contents(self, filename):
+        return self._archive.read(filename)
+
+    def members(self):
         return [
-            filename for filename in self.zf.namelist() if not filename.endswith('/')
+            filename for filename in self._archive.namelist() if not filename.endswith('/')
         ]
 
-    def get_content(self, filename):
-        return self.zf.read(filename)
+    def open_member(self, filename):
+        return self._archive.open(filename)
 
     def write(self, filename=None):
         # fix for Linux zip files read in Windows
-        for file in self.zf.filelist:
-            file.create_system = 0
+        for entry in self._archive.filelist:
+            entry.create_system = 0
 
-        self.descriptor.seek(0)
+        self.string_buffer.seek(0)
 
         if filename:
-            descriptor = open(filename, 'w')
-            descriptor.write(self.descriptor.read())
+            with open(filename, 'w') as file_object:
+                file_object.write(self.string_buffer.read())
         else:
-            return self.descriptor
+            return self.string_buffer
 
     def as_file(self, filename):
         return SimpleUploadedFile(name=filename, content=self.write().read())
 
-    def children(self):
-        try:
-            # Try for a ZIP file
-            zfobj = zipfile.ZipFile(self.file_object)
-            filenames = [
-                filename for filename in zfobj.namelist() if not filename.endswith('/')
-            ]
-            return (
-                SimpleUploadedFile(
-                    name=filename, content=zfobj.read(filename)
-                ) for filename in filenames
-            )
-        except zipfile.BadZipfile:
-            raise NotACompressedFile
 
-    def close(self):
-        self.zf.close()
+Archive.register(
+    mime_types=('application/zip',), archive_classes=(ZipArchive,)
+)
+Archive.register(
+    mime_types=('application/x-tar',), archive_classes=(TarArchive,)
+)
+Archive.register(
+    mime_types=('application/gzip',), archive_classes=(TarArchive,)
+)
+Archive.register(
+    mime_types=('application/x-bzip2',), archive_classes=(TarArchive,)
+)

mayan/apps/common/exceptions.py

@@ -15,6 +15,19 @@ class ActionError(BaseCommonException):
     it is used to announce that one item in the queryset failed to process.
     """
 
+class CompressionFileError(BaseCommonException):
+    """
+    Base exception for file decompression class
+    """
+    pass
+
+
+class NoMIMETypeMatch(CompressionFileError):
+    """
+    There is no decompressor registered for the specified MIME type
+    """
+    pass
+
 
 class NotLatestVersion(BaseCommonException):
     """

mayan/apps/common/tests/contrib/test_file1.txt

@@ -0,0 +1 @@
+TEST FILE 1

mayan/apps/common/tests/contrib/test_file2.txt

@@ -0,0 +1 @@
+TEST FILE 2

mayan/apps/common/tests/contrib/test_file3.txt

@@ -0,0 +1 @@
+TEST FILE 3

mayan/apps/common/tests/literals.py

@@ -1,5 +1,38 @@
 from __future__ import unicode_literals
 
+import os
+
+from django.conf import settings
+
 TEST_ERROR_LOG_ENTRY_RESULT = 'test_error_log_entry_result_text'
 TEST_VIEW_NAME = 'test view name'
 TEST_VIEW_URL = 'test-view-url'
+
+# Filenames
+TEST_FILENAME1 = 'test_file1.txt'
+TEST_FILENAME2 = 'test_file2.txt'
+TEST_FILENAME3 = 'test_file3.txt'
+TEST_FILE_CONTENTS_1 = 'TEST FILE 1\n'
+TEST_FILE_CONTENTS_2 = 'TEST FILE 2\n'
+TEST_TAR_BZ2_FILE = 'test_file.tar.bz2'
+TEST_TAR_FILE = 'test_file.tar'
+TEST_TAR_GZ_FILE = 'test_file.tar.gz'
+TEST_ZIP_FILE = 'test_file.zip'
+TEST_COMPRESSED_FILE_CONTENTS = [TEST_FILENAME1, TEST_FILENAME2]
+
+# File paths
+TEST_FILE3_PATH = os.path.join(
+    settings.BASE_DIR, 'apps', 'common', 'tests', 'contrib', TEST_FILENAME3
+)
+TEST_TAR_BZ2_FILE_PATH = os.path.join(
+    settings.BASE_DIR, 'apps', 'common', 'tests', 'contrib', TEST_TAR_BZ2_FILE
+)
+TEST_TAR_FILE_PATH = os.path.join(
+    settings.BASE_DIR, 'apps', 'common', 'tests', 'contrib', TEST_TAR_FILE
+)
+TEST_TAR_GZ_FILE_PATH = os.path.join(
+    settings.BASE_DIR, 'apps', 'common', 'tests', 'contrib', TEST_TAR_GZ_FILE
+)
+TEST_ZIP_FILE_PATH = os.path.join(
+    settings.BASE_DIR, 'apps', 'common', 'tests', 'contrib', TEST_ZIP_FILE
+)

mayan/apps/common/tests/test_compressed_files.py

@@ -0,0 +1,70 @@
+from __future__ import unicode_literals
+
+from common.tests import BaseTestCase
+from django.test import override_settings
+
+from ..compressed_files import Archive, TarArchive, ZipArchive
+
+from .literals import (
+    TEST_COMPRESSED_FILE_CONTENTS, TEST_FILE_CONTENTS_1, TEST_FILE_CONTENTS_2,
+    TEST_FILE3_PATH, TEST_FILENAME1, TEST_FILENAME2, TEST_FILENAME3,
+    TEST_TAR_BZ2_FILE_PATH, TEST_TAR_FILE_PATH, TEST_TAR_GZ_FILE_PATH,
+    TEST_ZIP_FILE_PATH
+)
+
+
+class TarArchiveClassTestCase(BaseTestCase):
+    archive_path = TEST_TAR_FILE_PATH
+    cls = TarArchive
+    filename = TEST_FILENAME3
+    file_path = TEST_FILE3_PATH
+    members_list = TEST_COMPRESSED_FILE_CONTENTS
+    member_name = TEST_FILENAME1
+    member_contents = TEST_FILE_CONTENTS_1
+
+    def test_add_file(self):
+        archive = self.cls()
+        archive.create()
+        with open(self.file_path) as file_object:
+            archive.add_file(file_object=file_object, filename=self.filename)
+            self.assertTrue(archive.members(), [self.filename])
+
+    def test_open(self):
+        with open(self.archive_path) as file_object:
+            archive = Archive.open(file_object=file_object)
+            self.assertTrue(isinstance(archive, self.cls))
+
+    def test_members(self):
+        with open(self.archive_path) as file_object:
+            archive = Archive.open(file_object=file_object)
+            self.assertEqual(archive.members(), self.members_list)
+
+    def test_member_contents(self):
+        with open(self.archive_path) as file_object:
+            archive = Archive.open(file_object=file_object)
+            self.assertEqual(
+                archive.member_contents(filename=self.member_name), self.member_contents
+            )
+
+    def test_open_member(self):
+        with open(self.archive_path) as file_object:
+            archive = Archive.open(file_object=file_object)
+            file_object = archive.open_member(filename=self.member_name)
+            self.assertEqual(
+                file_object.read(), self.member_contents
+            )
+
+
+class ZipArchiveClassTestCase(TarArchiveClassTestCase):
+    archive_path = TEST_ZIP_FILE_PATH
+    cls = ZipArchive
+
+
+class TarGzArchiveClassTestCase(TarArchiveClassTestCase):
+    archive_path = TEST_TAR_GZ_FILE_PATH
+    cls = TarArchive
+
+
+class TarBz2ArchiveClassTestCase(TarArchiveClassTestCase):
+    archive_path = TEST_TAR_BZ2_FILE_PATH
+    cls = TarArchive

mayan/apps/documents/views/document_views.py

@@ -11,7 +11,7 @@ from django.utils.http import urlencode
 from django.utils.translation import ugettext_lazy as _, ungettext
 
 from acls.models import AccessControlList
-from common.compressed_files import CompressedFile
+from common.compressed_files import ZipArchive
 from common.exceptions import ActionError
 from common.generics import (
     ConfirmView, FormView, MultipleObjectConfirmActionView,
@@ -553,22 +553,22 @@ class DocumentDownloadView(SingleObjectDownloadView):
         )
 
         if self.request.GET.get('compressed') == 'True' or queryset.count() > 1:
-            compressed_file = CompressedFile()
+            compressed_file = ZipArchive()
+            compressed_file.create()
             for item in queryset:
-                descriptor = DocumentDownloadView.get_item_file(item=item)
-                compressed_file.add_file(
-                    descriptor, arcname=self.get_item_label(item=item)
-                )
-                descriptor.close()
-                DocumentDownloadView.commit_event(
-                    item=item, request=self.request
-                )
+                with DocumentDownloadView.get_item_file(item=item) as file_object:
+                    compressed_file.add_file(
+                        file_object=file_object,
+                        filename=self.get_item_label(item=item)
+                    )
+                    DocumentDownloadView.commit_event(
+                        item=item, request=self.request
+                    )
 
             compressed_file.close()
 
             return DocumentDownloadView.VirtualFile(
-                compressed_file.as_file(zip_filename),
-                name=zip_filename
+                compressed_file.as_file(zip_filename), name=zip_filename
             )
         else:
             item = queryset.first()

mayan/apps/sources/models.py

@@ -21,7 +21,8 @@ from django.utils.translation import ugettext_lazy as _
 
 from model_utils.managers import InheritanceManager
 
-from common.compressed_files import CompressedFile, NotACompressedFile
+from common.compressed_files import Archive
+from common.exceptions import NoMIMETypeMatch
 from common.utils import TemporaryFile
 from converter.models import Transformation
 from djcelery.models import PeriodicTask, IntervalSchedule
@@ -88,24 +89,24 @@ class Source(models.Model):
 
         kwargs = {
             'description': description, 'document_type': document_type,
-            'label': label, 'language': language,
-            'user': user
+            'label': label, 'language': language, 'user': user
         }
 
         if expand:
             try:
-                compressed_file = CompressedFile(file_object)
-                for compressed_file_child in compressed_file.children():
-                    kwargs.update({'label': force_text(compressed_file_child)})
-                    documents.append(
-                        self.upload_document(
-                            file_object=File(compressed_file_child), **kwargs
+                compressed_file = Archive.open(file_object=file_object)
+                for compressed_file_child in compressed_file.members():
+                    with compressed_file.open_member(filename=compressed_file_child) as file_object:
+                        kwargs.update(
+                            {'label': force_text(compressed_file_child)}
                         )
-                    )
-                    compressed_file_child.close()
-
-            except NotACompressedFile:
-                logging.debug('Exception: NotACompressedFile')
+                        documents.append(
+                            self.upload_document(
+                                file_object=file_object, **kwargs
+                            )
+                        )
+            except NoMIMETypeMatch:
+                logging.debug('Exception: NoMIMETypeMatch')
                 documents.append(
                     self.upload_document(file_object=file_object, **kwargs)
                 )

mayan/apps/sources/tasks.py

@@ -9,7 +9,8 @@ from django.utils.translation import ugettext_lazy as _
 
 from mayan.celery import app
 
-from common.compressed_files import CompressedFile, NotACompressedFile
+from common.compressed_files import Archive
+from common.exceptions import NoMIMETypeMatch
 from lock_manager import LockError
 from lock_manager.runtime import locking_backend
 
@@ -138,7 +139,7 @@ def task_source_handle_upload(self, document_type_id, shared_uploaded_file_id, s
     with shared_upload.open() as file_object:
         if expand:
             try:
-                compressed_file = CompressedFile(file_object)
+                compressed_file = Archive.open(file_object=file_object)
                 for compressed_file_child in compressed_file.children():
                     # TODO: find way to uniquely identify child files
                     # Use filename in the mean time.
@@ -187,8 +188,8 @@ def task_source_handle_upload(self, document_type_id, shared_uploaded_file_id, s
                         'upload file: %s; %s. Retrying.', shared_upload,
                         exception
                     )
-            except NotACompressedFile:
-                logging.debug('Exception: NotACompressedFile')
+            except NoMIMETypeMatch:
+                logging.debug('Exception: NoMIMETypeMatch')
                 task_upload_document.delay(
                     shared_uploaded_file_id=shared_upload.pk, **kwargs
                 )