TypeError: can't compare datetime.datetime to str

[miendo]

How to Reproduce

While doing a GET operation on /query, Trac issued an internal error.

(please provide additional details here)

Request parameters:

{'col': #u'id',
         u'summary',
         u'type',
         u'severity',
         u'due_assign',
         u'due_close',
         u'release_date'#,
 'group': u'owner',
 'order': u'due_close',
 'report': u'12',
 'status': #u'accepted', u'assigned', u'new', u'reopened'#}

User agent: Mozilla/4#0 #compatible; MSIE 7#0; Windows NT 6#1; WOW64; Trident/7#0; SLCC2; #NET CLR 2#0#50727; #NET CLR 3#5#30729; #NET CLR 3#0#30729; Media Center PC 6#0; InfoPath#3; #NET4#0C; #NET4#0E#

System Information

Trac	0#12
Babel	0#9#5
Genshi	0#6
mod_python	3#2#8
pysqlite	2#3#3
Python	2#4#3 ##1, Jan 9 2013, 06:47:03# ##br## #GCC 4#1#2 20080704 #Red Hat 4#1#2-54##
RPC	1#1#0
setuptools	0#6c7
SQLite	3#3#6
Subversion	1#6#15 #r1038135#
jQuery	1#4#2

Enabled Plugins

TracDecoratorPlugin	0#3#1
TracGanttCalendarPlugin	0#6#2
TracMenusPlugin	0#1
TracWysiwyg	0#12#0#2
TracXMLRPC	1#1#0

Python Traceback

Traceback #most recent call last#:
  File "/usr/lib/python2#4/site-packages/trac/web/main#py", line 513, in _dispatch_request
    dispatcher#dispatch#req#
  File "/usr/lib/python2#4/site-packages/trac/web/main#py", line 235, in dispatch
    resp = chosen_handler#process_request#req#
  File "/usr/lib/python2#4/site-packages/trac/ticket/query#py", line 933, in process_request
    return self#display_html#req, query#
  File "/usr/lib/python2#4/site-packages/trac/ticket/query#py", line 1052, in display_html
    data = query.template_data#context, tickets, orig_list, orig_time, req#
  File "/usr/lib/python2.4/site-packages/trac/ticket/query.py", line 732, in template_data
    elif ticket['changetime'] > orig_time:
TypeError: can't compare datetime.datetime to str

[Ryan J Ollos]

Issue previously reported in #10030, #10258 and #6088. Perhaps we need to consider having better protection against the possibility of a NULL or empty string in the changetime and time columns.

Maybe this happens with imported tickets, or tickets created through the XmlRpc interface? In 3 of the 4 tickets users have shown ​XmlRpcPlugin installed.

It would be useful to see a query of your database, like the one shown in comment:16:ticket:6088:

$ sqlite3 db/trac.db 

SQLite version 3.8.5 2014-08-15 22:37:57
Enter ".help" for usage hints.
sqlite> SELECT id FROM ticket WHERE changetime IS NULL OR changetime=''; 

[Ryan J Ollos]

I can reproduce on the trunk at least, by setting changetime to NULL.

[Ryan J Ollos]

Narrowing focus for milestone:1.2. Please move ticket to milestone:1.2 if you intend to fix it.

[simon.jakobi@…]

I ran into this issue at ​ghc.haskell.org/trac.

The following patch seems to fix it:

Index: trac/ticket/query.py
===================================================================
--- trac/ticket/query.py	(Revision 16436)
+++ trac/ticket/query.py	(Arbeitskopie)
@@ -775,9 +775,10 @@
             if orig_list:
                 # Mark tickets added or changed since the query was first
                 # executed
-                if ticket['time'] > orig_time:
+                if ticket['time'] and (ticket['time'] > orig_time):
                     ticket['added'] = True
-                elif ticket['changetime'] > orig_time:
+                elif (ticket['changetime'] and 
+                        (ticket['changetime'] > orig_time)):
                     ticket['changed'] = True
             if self.group:
                 group_key = ticket[self.group]

I've tested this manually by inserting NULL into the changetime and time fields.

[Jun Omae]

Thanks for the patch and helpful hints.

472 tickets has empty changetime on ghc.haskell.org/trac. See ​https://ghc.haskell.org/trac/ghc/query?changetime=19700101T000000Z..19700101T000001Z&col=changetime&order=id&max=10 (if the same error is occurred, clear last query in report page).

• ​https://ghc.haskell.org/trac/ghc/ticket/587 is created 16 years ago and changetime is empty.
• ​https://ghc.haskell.org/trac/ghc/ticket/588 is created 12 years ago and changetime is not empty.

[Ryan J Ollos]

I think we could probably simplify patch using ticket.get('changetime') rather than ticket['changetime'] and ..., since the comparison will always evaluate to False if ticket.get('changetime') is None.

[Jun Omae]

• ​https://ghc.haskell.org/trac/ghc/ticket/587 is created 16 years ago and changetime is empty.
• ​https://ghc.haskell.org/trac/ghc/ticket/588 is created 12 years ago and changetime is not empty.

Trac 0.5 is first released on Feb 23, 2004 (14 years ago) but the above tickets are opened on 2001…. See also source:/tags/trac-0.5.2/ChangeLog#L28​.

[Jun Omae]

Behaviors between 1.2.2 and 1.0.15 are different for changetime column being NULL.

Trac version	changetime value in query
1.2.2	''
1.0.15	datetime(1970, 1, 1, tzinfo=utc)

Reproduced it on Trac 1.2.2 but not on Trac 1.0.15.

Trac 1.2.2:

>>> import pprint
>>> from trac import __version__
>>> __version__
'1.2.2'
>>> from trac.test import EnvironmentStub
>>> from trac.ticket.query import Query
>>> env = EnvironmentStub()
>>> env.db_transaction("INSERT INTO ticket (summary,status,time,changetime) VALUES ('#12029','new',strftime('%s','now')*1000000,NULL)")
>>> env.db_query('SELECT * FROM ticket WHERE id=1')[0]
(1, None, 1519969856000000L, None, None, None, None, None, None, None, None, None, u'new', None, u'#12029', None, None)
>>> pprint.pprint(Query.from_string(env, 'id=1').execute())
[{u'_priority_value': '',
  u'changetime': '',
  u'id': 1,
  u'owner': '',
  u'priority': '',
  u'status': u'new',
  u'summary': u'#12029',
  u'time': datetime.datetime(2018, 3, 2, 5, 50, 56, tzinfo=<FixedOffset "UTC" 0:00:00>)}]

Trac 1.0.15:

>>> from trac import __version__
>>> __version__
'1.0.15'
>>> from trac.test import EnvironmentStub
env = EnvironmentStub()
env.db_transaction("INSERT INTO ticket (summary,status,time,changetime) VALUES ('#12029','new',strftime('%s','now')*1000000,NULL)")
env.db_query('SELECT * FROM ticket WHERE id=1')[0]
>>> from trac.ticket.query import Query
>>> env = EnvironmentStub()
>>> env.db_transaction("INSERT INTO ticket (summary,status,time,changetime) VALUES ('#12029','new',strftime('%s','now')*1000000,NULL)")
>>> env.db_query('SELECT * FROM ticket WHERE id=1')[0]
(1, None, 1519970122000000L, None, None, None, None, None, None, None, None, None, u'new', None, u'#12029', None, None)
>>> import pprint
>>> pprint.pprint(Query.from_string(env, 'id=1').execute())
[{u'changetime': datetime.datetime(1970, 1, 1, 0, 0, tzinfo=<FixedOffset "UTC" 0:00:00>),
  u'id': 1,
  u'owner': '',
  u'priority': '',
  u'priority_value': '',
  u'status': u'new',
  u'summary': u'#12029',
  u'time': datetime.datetime(2018, 3, 2, 5, 55, 22, tzinfo=<FixedOffset "UTC" 0:00:00>)}]

[Jun Omae]

It seems the difference is introduced in [11331#file3] (#1942).

                             result['href'] = href.ticket(val)
                     elif name in self.time_fields:
-                        val = from_utimestamp(val)
+                        val = from_utimestamp(long(val)) if val else ''
                     elif field and field['type'] == 'checkbox':
                         try:

I guess ​tickets #1-587 on ghc are manually imported cause of changetime being NULL.

I consider we should add not-null constraint to time and changetime of ticket table to avoid such accidents.

[anonymous]

(Those tickets contain comments with Logged In: YES user_id=... characteristic of being imported from sourceforge?)

[Jun Omae]

Replying to anonymous:

(Those tickets contain comments with Logged In: YES user_id=... characteristic of being imported from sourceforge?)

First version of sourceforge2trac.py uses changetime='' at source:trunk/contrib/sourceforge2trac.py@475:260#L248​.

[simon.jakobi@…]

Replying to Ryan J Ollos:

I think we could probably simplify patch using ticket.get('changetime') rather than ticket['changetime'] and ..., since the comparison will always evaluate to False if ticket.get('changetime') is None.

ticket['changetime'] appears to be the empty string in my case.

[Jun Omae]

Trac doesn't expect NULL in changetime column, which is lead by issue in first version of sourceforge2trac.py.

Please update changetime column with value of time column for records which have NULL in the changetime column.

UPDATE ticket SET changetime = time WHERE changetime IS NULL

[Simon Jakobi <simon.jakobi@…>]

Replying to Jun Omae:

UPDATE ticket SET changetime = time WHERE changetime IS NULL

Thanks! This looks like an easy fix.

[Jun Omae]

Replying to Ryan J Ollos:

I think we could probably simplify patch using ticket.get('changetime') rather than ticket['changetime'] and ..., since the comparison will always evaluate to False if ticket.get('changetime') is None.

TypeError is actually raised when datetime and None are compared.

$ ~/venv/trac/1.0.15/bin/python
Python 2.5.6 (r256:88840, Oct 21 2014, 22:49:55)
[GCC 4.8.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> from datetime import datetime
>>> from trac.util.datefmt import utc
>>> ticket = {}
>>> orig_time = datetime.now(utc)
>>> ticket.get('changetime') > orig_time
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: can't compare datetime.datetime to NoneType

Also, the ticket dictionary always has time and changetime by add_cols(..., 'time', 'changetime') at source:/tags/trac-1.0.15/trac/ticket/query.py@:443#L422​.

[Jun Omae]

Replying to Jun Omae:

Behaviors between 1.2.2 and 1.0.15 are different for changetime column being NULL.

Trac version	changetime value in query
1.2.2	''
1.0.15	datetime(1970, 1, 1, tzinfo=utc)

After [11331] (#1942), value of the time field is an empty string when the column has NULL but even if the column is a time field in custom field.

That is bad behavior. I think the time field should return None rather an empty string for the time field which has NULL value.

[Jun Omae]

Proposed changes in [efb9146e9/jomae.git] (jomae.git@t12029_1.2).

[Ryan J Ollos]

Looks good. The change mirrors behavior of _db_str_to_datetime​, used in _fetch_ticket​.

Is the last call to mod.process_request(req) intentional, after the assertion, to ensure the exception is not raised? If so, a comment would be good to ensure it's not accidentally deleted later.

Unrelated, but noticed while study code. I propose the following refactoring:

trac/ticket/query.py

@@ -313 +313 @@
 
             for row in cursor:
                 result = {}
-                for i in xrange(len(columns)):
-                    name, field, val = columns[i], fields[i], row[i]
+                for name, field, val in zip(columns, fields, row):
                     if name == 'reporter':
                         val = val or 'anonymous'
                     elif name == 'id':

[Jun Omae]

Thanks for the reviewing. Revised jomae.git@t12029_1.2.

Noticed minor issue while modifying code. Using added/changed/removed as custom fields, query results are highlighted. I've filed in #13007.

[Jun Omae]

Committed in [16499] and merged in [16500].