add some more checks.

src/documents/checks.py

@@ -4,6 +4,8 @@
 from django.core.checks import Error, register
 from django.db.utils import OperationalError, ProgrammingError
 
+from documents.signals import document_consumer_declaration
+
 
 @register()
 def changed_password_check(app_configs, **kwargs):
@@ -37,3 +39,17 @@ def changed_password_check(app_configs, **kwargs):
                 """))]
 
     return []
+
+
+@register()
+def parser_check(app_configs, **kwargs):
+
+    parsers = []
+    for response in document_consumer_declaration.send(None):
+        parsers.append(response[1])
+
+    if len(parsers) == 0:
+        return [Error("No parsers found. This is a bug. The consumer won't be "
+                      "able to onsume any documents without parsers.")]
+    else:
+        return []

src/documents/parsers.py

@@ -45,8 +45,6 @@ def get_parser_class(doc):
     for response in document_consumer_declaration.send(None):
         parsers.append(response[1])
 
-    # TODO: add a check that checks parser availability.
-
     options = []
     for parser in parsers:
         result = parser(doc)

src/paperless/checks.py

@@ -67,3 +67,16 @@ def binaries_check(app_configs, **kwargs):
             check_messages.append(Warning(error.format(binary), hint))
 
     return check_messages
+
+
+@register()
+def debug_mode_check(app_configs, **kwargs):
+    if settings.DEBUG:
+        return [Warning("DEBUG mode is enabled. Disable Debug mode. "
+                        "This is a serious security "
+                        "issue, since it puts security overides in place which"
+                        "are meant to be only used during development. This"
+                        "also means that paperless will tell anyone various"
+                        "debugging information when something goes wrong.")]
+    else:
+        return []