AttributeError: 'list' object has no attribute 'strip'

[rolf.wester@…]

I just started using Trac, thanks to all who developed it.

After creating my first ticket I wanted to change the assignment but got the error listed below. Then I tried to set "Action: leave as new" but got the same error. I found some similar error reports that are 2 years old but I don't know whether they are really related or not, so I'm creating this report.

Python Traceback

Traceback (most recent call last):
  File "C:\Python24\lib\site-packages\trac\web\main.py", line 406, in dispatch_request
    dispatcher.dispatch(req)
  File "C:\Python24\lib\site-packages\trac\web\main.py", line 237, in dispatch
    resp = chosen_handler.process_request(req)
  File "C:\Python24\lib\site-packages\trac\ticket\web_ui.py", line 290, in process_request
    self._do_save(req, db, ticket)
  File "C:\Python24\lib\site-packages\trac\ticket\web_ui.py", line 517, in _do_save
    ticket.populate(req.args)
  File "C:\Python24\lib\site-packages\trac\ticket\model.py", line 124, in populate
    self[name] = values.get(name, '')
  File "C:\Python24\lib\site-packages\trac\ticket\model.py", line 117, in __setitem__
    value = value.strip()
AttributeError: 'list' object has no attribute 'strip'

[Emmanuel Blot]

When you submit a new ticket, please always specify the version of Trac you're using, and use verbatim blocks {{{ ... }}} to quote tracebacks. TIA.

[Christian Boos]

It's actually easy to reproduce: this is triggered when multiple values are specified for the same field, e.g. newticket. That's not how the original reporter triggered the issue (he was doing a POST) so it's not clear how that have happened for him (a plugin? local modifications to the template? more info on this still appreciated).

While we don't currently support multiple values for a field, that's more a limitation than a feature (see #918 and #4298, eventually also #2662 depending how we'll implement that).

But first, we should produce a nicer error than this internal.

[anonymous]

I do:

klick "View Tickets" klick "Active Tickets" klick the first (and until now only) Ticket klick "Submit changes"

The version we are using is 0.10.4.

[Christian Boos]

Do you have custom ticket fields, if yes, can you copy your [ticket-custom] section from your trac.ini file here?

[anonymous]

The ticket-custom section of our trac.ini file is as follows:

[ticket-custom]
dependencies = text
dependencies.label = Abh~ngigkeiten (Tickets)
dependencies.order = 2
due_assign = text
due_assign.label = Bis wann zu best~tigen
due_assign.order = 1
due_assign.value = DD/MM/2008
due_close = text
due_close.label = Bis wann zu erledigen
due_close.order = 3
due_close.value = DD/MM/2008
include_gantt = checkbox
include_gantt.label = In Gant anzeigen
include_gantt.order = 4

[Christian Boos]

Any chance you're using a plugin that would also use on of these fields? Check the sources of your plugins, and grep for 'dependencies', 'due_assign', etc.

[anonymous]

There are plugins but I couldn't find any 'dependencies' or 'due_assign'. I put a write statement into model.py:

    def __setitem__(self, name, value):
        """Log ticket modifications so the table ticket_change can be updated"""
        if self.values.has_key(name) and self.values[name] == value:
            return
        if not self._old.has_key(name): # Changed field
            self._old[name] = self.values.get(name)
        elif self._old[name] == value: # Change of field reverted
            del self._old[name]
        if value:
            aus = open('D:\\trac.log','a')
            aus.write('%s  %s' % (name.__str__(), value.__str__()))
            aus.close()
            field = [field for field in self.fields if field['name'] == name]
            if field and field[0].get('type') != 'textarea':
                value = value.strip()
        self.values[name] = value

The following was written to trac.log:

component [u'component1', u'component1']

Does this help?

[Christian Boos]

Well, yes a bit, as we now see that the field in question is 'component', not a custom field as I thought. So maybe there's a plugin which sets this? Or a local modification to the templates? Something must be different on your system, as in a normal setup, the ticket forms won't set the 'component' argument twice. You can check what the ticket page form contains with "View sources" in your browser, maybe that will give an hint.

[anonymous]

Things are a little bit strange. Firefox shows the elements "Priority, "Milestone", "Component" and "Version" twice, although they only appear once in the page source. I didn't install Trac so I have to ask my colleague who did it. Thanks so far for your help.

[anonymous]

This looks like this: ​http://www.trac-hacks.org/ticket/2042

[Christian Boos]

Fixed in r7023.

Multi-valued fields support will be a topic for further data model improvements (TracDev/Proposals/DataModel).