mediawiki: Backup and restore uploaded files

Fixes #1747

MediaWiki on Debian seems to store all uploaded files under images/
folder. The administrator can enable additional file types. In the
default configuration, only image files are permitted.

Manually tested that backup/restore works irrespective of file type.

Signed-off-by: Joseph Nuthalapati <njoseph@riseup.net>
Reviewed-by: Sunil Mohan Adapa <sunil@medhas.org>

plinth/modules/mediawiki/manifest.py

@@ -15,7 +15,9 @@ backup = {
         'files': ['/etc/mediawiki/FreedomBoxSettings.php']
     },
     'data': {
-        'directories': ['/var/lib/mediawiki-db/']
+        'directories': [
+            '/var/lib/mediawiki-db/', '/var/lib/mediawiki/images/'
+        ]
     },
     'services': ['mediawiki-jobrunner']
 }

plinth/modules/mediawiki/tests/mediawiki.feature

@@ -67,12 +67,15 @@ Scenario: Upload SVG image
 @backups
 Scenario: Backup and restore mediawiki
   Given the mediawiki application is enabled
+  And I ensure that there is Noise.png image with credentials admin and whatever123
   When I create a backup of the mediawiki app data with name test_mediawiki
-  When I enable mediawiki public registrations
-  And I delete the mediawiki main page
+  And I enable mediawiki public registrations
+  And I delete Noise.png image with credentials admin and whatever123
+  And I delete the mediawiki main page with credentials admin and whatever123
   And I restore the mediawiki app data backup with name test_mediawiki
   Then the mediawiki main page should be restored
-  Then the mediawiki site should allow creating accounts
+  And there should be Noise.png image
+  And the mediawiki site should allow creating accounts
 
 Scenario: Disable mediawiki application
   Given the mediawiki application is enabled

plinth/modules/mediawiki/tests/test_functional.py

@@ -6,10 +6,10 @@ Functional, browser based tests for mediawiki app.
 import pathlib
 from urllib.parse import urlparse
 
-from pytest_bdd import given, parsers, scenarios, then, when
-
+import requests
 from plinth.tests import functional
 from plinth.tests.functional import config
+from pytest_bdd import given, parsers, scenarios, then, when
 
 scenarios('mediawiki.feature')
 
@@ -76,9 +76,18 @@ def login_to_mediawiki_with_credentials(session_browser, username, password):
     _login_with_credentials(session_browser, username, password)
 
 
-@when('I delete the mediawiki main page')
-def mediawiki_delete_main_page(session_browser):
-    _delete_main_page(session_browser)
+@when(
+    parsers.parse('I delete the mediawiki main page with credentials '
+                  '{username:w} and {password:w}'))
+def mediawiki_delete_main_page(session_browser, username, password):
+    _delete_main_page(session_browser, username, password)
+
+
+@when(
+    parsers.parse('I delete {image:S} image with credentials '
+                  '{username:w} and {password:w}'))
+def delete_image(session_browser, username, password, image):
+    _delete_image(session_browser, username, password, image)
 
 
 @then('the mediawiki main page should be restored')
@@ -94,10 +103,17 @@ def upload_image(session_browser, username, password, image):
     _upload_image(session_browser, username, password, image)
 
 
+@given(
+    parsers.parse('I ensure that there is {image:S} image with credentials '
+                  '{username:w} and {password:w}'))
+def ensure_image_exists(session_browser, username, password, image):
+    if not _image_exists(session_browser, image):
+        _upload_image(session_browser, username, password, image)
+
+
 @then(parsers.parse('there should be {image:S} image'))
 def uploaded_image_should_be_available(session_browser, image):
-    uploaded_image = _get_uploaded_image(session_browser, image)
-    assert image.lower() == uploaded_image.lower()
+    assert _image_exists(session_browser, image)
 
 
 def _enable_public_registrations(browser):
@@ -179,7 +195,7 @@ def _login_with_credentials(browser, username, password):
                                  args=['t-upload'])
 
 
-def _upload_image(browser, username, password, image):
+def _upload_image(browser, username, password, image, ignore_warnings=True):
     """Upload an image to MediaWiki. Idempotent."""
     functional.visit(browser, '/mediawiki')
     _login(browser, username, password)
@@ -187,25 +203,43 @@ def _upload_image(browser, username, password, image):
     # Upload file
     functional.visit(browser, '/mediawiki/Special:Upload')
     file_path = pathlib.Path(__file__).parent
-    file_path /= '../../../../static/themes/default/img/' + image
+    file_path /= '../../../../static/themes/default/img/' + image.lower()
     browser.attach_file('wpUploadFile', str(file_path.resolve()))
+    if ignore_warnings:  # allow uploading file with the same name
+        browser.find_by_name('wpIgnoreWarning').first.click()
     functional.submit(browser, element=browser.find_by_name('wpUpload')[0])
 
 
+def _delete_image(browser, username, password, image):
+    """Delete an image from MediaWiki."""
+    _login(browser, username, password)
+    path = f'/mediawiki/index.php?title=File:{image}&action=delete'
+    functional.visit(browser, path)
+    delete_button = browser.find_by_id('mw-filedelete-submit')
+    functional.submit(browser, element=delete_button)
+
+
 def _get_number_of_uploaded_images(browser):
     functional.visit(browser, '/mediawiki/Special:ListFiles')
     return len(browser.find_by_css('.TablePager_col_img_timestamp'))
 
 
-def _get_uploaded_image(browser, image):
+def _image_exists(browser, image):
+    """Check whether the given image exists."""
     functional.visit(browser, '/mediawiki/Special:ListFiles')
     elements = browser.find_link_by_partial_href(image)
-    return elements[0].value
+    if not elements:  # Necessary but insufficient check.
+        # Special:ListFiles also shows deleted images.
+        return False
+
+    # The second hyperlink is a direct link to the image.
+    response = requests.get(elements[1]['href'], verify=False)
+    return response.status_code != 404
 
 
-def _delete_main_page(browser):
+def _delete_main_page(browser, username, password):
     """Delete the mediawiki main page."""
-    _login(browser, 'admin', 'whatever123')
+    _login(browser, username, password)
     functional.visit(browser,
                      '/mediawiki/index.php?title=Main_Page&action=delete')
     with functional.wait_for_page_update(browser):