WandbCallback does not work

[jakubLangr]

I think this is a function of the latest changes (that I generally massively support), but just thought I'd point out this issue. I will investigate it tomorrow. To see if I can fix it.

On the line in the camvid notebook:
learn.fit_one_cycle(10, slice(lr), pct_start=0.9, wd=1e-2)
If we add (incl. appropriate imports & setup).
learn.fit_one_cycle(10, slice(lr), pct_start=0.9, wd=1e-2, cbs=WandbCallback())
It raises this issue:

---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
~/daisy-gan/venv/lib/python3.6/site-packages/fastai2/learner.py in fit(self, n_epoch, lr, wd, cbs, reset_opt)
    284             try:
--> 285                 self._do_begin_fit(n_epoch)
    286                 for epoch in range(n_epoch):

~/daisy-gan/venv/lib/python3.6/site-packages/fastai2/learner.py in _do_begin_fit(self, n_epoch)
    258     def _do_begin_fit(self, n_epoch):
--> 259         self.n_epoch,self.loss = n_epoch,tensor(0.);         self('begin_fit')
    260 

~/daisy-gan/venv/lib/python3.6/site-packages/fastai2/learner.py in __call__(self, event_name)
    222 
--> 223     def __call__(self, event_name): L(event_name).map(self._call_one)
    224     def _call_one(self, event_name):

~/daisy-gan/venv/lib/python3.6/site-packages/fastcore/foundation.py in map(self, f, *args, **kwargs)
    361              else f.__getitem__)
--> 362         return self._new(map(g, self))
    363 

~/daisy-gan/venv/lib/python3.6/site-packages/fastcore/foundation.py in _new(self, items, *args, **kwargs)
    314     def _xtra(self): return None
--> 315     def _new(self, items, *args, **kwargs): return type(self)(items, *args, use_list=None, **kwargs)
    316     def __getitem__(self, idx): return self._get(idx) if is_indexer(idx) else L(self._get(idx), use_list=None)

~/daisy-gan/venv/lib/python3.6/site-packages/fastcore/foundation.py in __call__(cls, x, *args, **kwargs)
     40 
---> 41         res = super().__call__(*((x,) + args), **kwargs)
     42         res._newchk = 0

~/daisy-gan/venv/lib/python3.6/site-packages/fastcore/foundation.py in __init__(self, items, use_list, match, *rest)
    305         if (use_list is not None) or not _is_array(items):
--> 306             items = list(items) if use_list else _listify(items)
    307         if match is not None:

~/daisy-gan/venv/lib/python3.6/site-packages/fastcore/foundation.py in _listify(o)
    241     if isinstance(o, str) or _is_array(o): return [o]
--> 242     if is_iter(o): return list(o)
    243     return [o]

~/daisy-gan/venv/lib/python3.6/site-packages/fastcore/foundation.py in __call__(self, *args, **kwargs)
    207         fargs = [args[x.i] if isinstance(x, _Arg) else x for x in self.pargs] + args[self.maxi+1:]
--> 208         return self.fn(*fargs, **kwargs)
    209 

~/daisy-gan/venv/lib/python3.6/site-packages/fastai2/learner.py in _call_one(self, event_name)
    225         assert hasattr(event, event_name)
--> 226         [cb(event_name) for cb in sort_by_run(self.cbs)]
    227 

~/daisy-gan/venv/lib/python3.6/site-packages/fastai2/learner.py in <listcomp>(.0)
    225         assert hasattr(event, event_name)
--> 226         [cb(event_name) for cb in sort_by_run(self.cbs)]
    227 

~/daisy-gan/venv/lib/python3.6/site-packages/fastai2/learner.py in __call__(self, event_name)
     24                (self.run_valid and not getattr(self, 'training', False)))
---> 25         if self.run and _run: getattr(self, event_name, noop)()
     26 

~/daisy-gan/venv/lib/python3.6/site-packages/fastai2/callback/wandb.py in begin_fit(self)
     47             test_tls = [tl._new(items, split_idx=1) for tl in self.dls.valid_ds.tls]
---> 48             self.valid_dl = self.dls.valid_dl.new(Datasets(tls=test_tls), bs=self.n_preds)
     49 

~/daisy-gan/venv/lib/python3.6/site-packages/fastcore/foundation.py in __getattr__(self, k)
    222             if attr is not None: return getattr(attr, k)
--> 223         raise AttributeError(k)
    224     def __dir__(self): return custom_dir(self, self._dir() if self._xtra is None else self._dir())

AttributeError: valid_dl

During handling of the above exception, another exception occurred:

AttributeError                            Traceback (most recent call last)
<ipython-input-19-cadf93af9e73> in <module>
----> 1 learn.fit_one_cycle(10, slice(lr), pct_start=0.9, wd=1e-2, cbs=WandbCallback())

~/daisy-gan/venv/lib/python3.6/site-packages/fastai2/callback/schedule.py in fit_one_cycle(self, n_epoch, lr_max, div, div_final, pct_start, wd, moms, cbs, reset_opt)
     88     scheds = {'lr': combined_cos(pct_start, lr_max/div, lr_max, lr_max/div_final),
     89               'mom': combined_cos(pct_start, *(self.moms if moms is None else moms))}
---> 90     self.fit(n_epoch, cbs=ParamScheduler(scheds)+L(cbs), reset_opt=reset_opt, wd=wd)
     91 
     92 # Cell

~/daisy-gan/venv/lib/python3.6/site-packages/fastai2/learner.py in fit(self, n_epoch, lr, wd, cbs, reset_opt)
    293 
    294             except CancelFitException:             self('after_cancel_fit')
--> 295             finally:                               self('after_fit')
    296 
    297     def validate(self, ds_idx=1, dl=None, cbs=None):

~/daisy-gan/venv/lib/python3.6/site-packages/fastai2/learner.py in __call__(self, event_name)
    221     def ordered_cbs(self, cb_func:str): return [cb for cb in sort_by_run(self.cbs) if hasattr(cb, cb_func)]
    222 
--> 223     def __call__(self, event_name): L(event_name).map(self._call_one)
    224     def _call_one(self, event_name):
    225         assert hasattr(event, event_name)

~/daisy-gan/venv/lib/python3.6/site-packages/fastcore/foundation.py in map(self, f, *args, **kwargs)
    360              else f.format if isinstance(f,str)
    361              else f.__getitem__)
--> 362         return self._new(map(g, self))
    363 
    364     def filter(self, f, negate=False, **kwargs):

~/daisy-gan/venv/lib/python3.6/site-packages/fastcore/foundation.py in _new(self, items, *args, **kwargs)
    313     @property
    314     def _xtra(self): return None
--> 315     def _new(self, items, *args, **kwargs): return type(self)(items, *args, use_list=None, **kwargs)
    316     def __getitem__(self, idx): return self._get(idx) if is_indexer(idx) else L(self._get(idx), use_list=None)
    317     def copy(self): return self._new(self.items.copy())

~/daisy-gan/venv/lib/python3.6/site-packages/fastcore/foundation.py in __call__(cls, x, *args, **kwargs)
     39             return x
     40 
---> 41         res = super().__call__(*((x,) + args), **kwargs)
     42         res._newchk = 0
     43         return res

~/daisy-gan/venv/lib/python3.6/site-packages/fastcore/foundation.py in __init__(self, items, use_list, match, *rest)
    304         if items is None: items = []
    305         if (use_list is not None) or not _is_array(items):
--> 306             items = list(items) if use_list else _listify(items)
    307         if match is not None:
    308             if is_coll(match): match = len(match)

~/daisy-gan/venv/lib/python3.6/site-packages/fastcore/foundation.py in _listify(o)
    240     if isinstance(o, list): return o
    241     if isinstance(o, str) or _is_array(o): return [o]
--> 242     if is_iter(o): return list(o)
    243     return [o]
    244 

~/daisy-gan/venv/lib/python3.6/site-packages/fastcore/foundation.py in __call__(self, *args, **kwargs)
    206             if isinstance(v,_Arg): kwargs[k] = args.pop(v.i)
    207         fargs = [args[x.i] if isinstance(x, _Arg) else x for x in self.pargs] + args[self.maxi+1:]
--> 208         return self.fn(*fargs, **kwargs)
    209 
    210 # Cell

~/daisy-gan/venv/lib/python3.6/site-packages/fastai2/learner.py in _call_one(self, event_name)
    224     def _call_one(self, event_name):
    225         assert hasattr(event, event_name)
--> 226         [cb(event_name) for cb in sort_by_run(self.cbs)]
    227 
    228     def _bn_bias_state(self, with_bias): return bn_bias_params(self.model, with_bias).map(self.opt.state)

~/daisy-gan/venv/lib/python3.6/site-packages/fastai2/learner.py in <listcomp>(.0)
    224     def _call_one(self, event_name):
    225         assert hasattr(event, event_name)
--> 226         [cb(event_name) for cb in sort_by_run(self.cbs)]
    227 
    228     def _bn_bias_state(self, with_bias): return bn_bias_params(self.model, with_bias).map(self.opt.state)

~/daisy-gan/venv/lib/python3.6/site-packages/fastai2/learner.py in __call__(self, event_name)
     23         _run = (event_name not in _inner_loop or (self.run_train and getattr(self, 'training', True)) or
     24                (self.run_valid and not getattr(self, 'training', False)))
---> 25         if self.run and _run: getattr(self, event_name, noop)()
     26 
     27     @property

~/daisy-gan/venv/lib/python3.6/site-packages/fastai2/callback/progress.py in after_fit(self)
     37     def after_fit(self):
     38         if getattr(self, 'mbar', False):
---> 39             self.mbar.on_iter_end()
     40             delattr(self, 'mbar')
     41         self.learn.logger = self.old_logger

~/daisy-gan/venv/lib/python3.6/site-packages/fastprogress/fastprogress.py in on_iter_end(self)
    155             total_time = format_time(time.time() - self.main_bar.start_t)
    156             self.text = f'Total time: {total_time} <p>' + self.text
--> 157         self.out.update(HTML(self.text))
    158 
    159     def add_child(self, child):

AttributeError: 'NBMasterBar' object has no attribute 'out'

[sgugger]

Closed by #66