That suggests the default label is created as that, which indeed causes the
duplication error.

On Tue, Oct 3, 2023 at 9:15 PM Joey Tran <joey.t...@schrodinger.com> wrote:

> Not sure what that suggests
>
> On Tue, Oct 3, 2023, 6:24 PM XQ Hu via user <user@beam.apache.org> wrote:
>
>> Looks like this is the current behaviour. If you have `t =
>> beam.Filter(identity_filter)`, `t.label` is defined as
>> `Filter(identity_filter)`.
>>
>> On Mon, Oct 2, 2023 at 9:25 AM Joey Tran <joey.t...@schrodinger.com>
>> wrote:
>>
>>> You don't have to specify the names if the callable you pass in is
>>> /different/ for two `beam.Map`s, but  if the callable is the same you must
>>> specify a label. For example, the below will raise an exception:
>>>
>>> ```
>>>         | beam.Filter(identity_filter)
>>>         | beam.Filter(identity_filter)
>>> ```
>>>
>>> Here's an example on playground that shows the error message you get
>>> [1]. I marked every line I added with a "# ++".
>>>
>>> It's a contrived example, but using a map or filter at the same pipeline
>>> level probably comes up often, at least in my inexperience. For example,
>>> you. might have a pipeline that partitions a pcoll into three different
>>> pcolls, runs some transforms on them, and then runs the same type of filter
>>> on each of them.
>>>
>>> The case that happens most often for me is using the `assert_that` [2]
>>> testing transform. In this case, I think often users will really have no
>>> need for a disambiguating label as they're often just writing unit tests
>>> that test a few different properties of their workflow.
>>>
>>> [1] https://play.beam.apache.org/?sdk=python&shared=hIrm7jvCamW
>>> [2]
>>> https://beam.apache.org/releases/pydoc/2.29.0/apache_beam.testing.util.html#apache_beam.testing.util.assert_that
>>>
>>> On Mon, Oct 2, 2023 at 9:08 AM Bruno Volpato via user <
>>> user@beam.apache.org> wrote:
>>>
>>>> If I understand the question correctly, you don't have to specify those
>>>> names.
>>>>
>>>> As Reuven pointed out, it is probably a good idea so you have a stable
>>>> / deterministic graph.
>>>> But in the Python SDK, you can simply use pcollection | map_fn,
>>>> instead of pcollection | 'Map' >> map_fn.
>>>>
>>>> See an example here
>>>> https://github.com/apache/beam/blob/master/sdks/python/apache_beam/examples/cookbook/group_with_coder.py#L100-L116
>>>>
>>>>
>>>> On Sun, Oct 1, 2023 at 9:08 PM Joey Tran <joey.t...@schrodinger.com>
>>>> wrote:
>>>>
>>>>> Hmm, I'm not sure what you mean by "updating pipelines in place". Can
>>>>> you elaborate?
>>>>>
>>>>> I forgot to mention my question is posed from the context of a python
>>>>> SDK user, and afaict, there doesn't seem to be an obvious way to
>>>>> autogenerate names/labels. Hearing that the java SDK supports it makes me
>>>>> wonder if the python SDK could support it as well though... (If so, I'd be
>>>>> happy to do implement it). Currently, it's fairly tedious to have to name
>>>>> every instance of a transform that you might reuse in a pipeline, e.g. 
>>>>> when
>>>>> reapplying the same Map on different pcollections.
>>>>>
>>>>> On Sun, Oct 1, 2023 at 8:12 PM Reuven Lax via user <
>>>>> user@beam.apache.org> wrote:
>>>>>
>>>>>> Are you talking about transform names? The main reason was because
>>>>>> for runners that support updating pipelines in place, the only way to do 
>>>>>> so
>>>>>> safely is if the runner can perfectly identify which transforms in the 
>>>>>> new
>>>>>> graph match the ones in the old graph. There's no good way to auto 
>>>>>> generate
>>>>>> names that will stay stable across updates - even small changes to the
>>>>>> pipeline might change the order of nodes in the graph, which could result
>>>>>> in a corrupted update.
>>>>>>
>>>>>> However, if you don't care about update, Beam can auto generate these
>>>>>> names for you! When you call PCollection.apply (if using BeamJava), 
>>>>>> simply
>>>>>> omit the name parameter and Beam will auto generate a unique name for 
>>>>>> you.
>>>>>>
>>>>>> Reuven
>>>>>>
>>>>>> On Sat, Sep 30, 2023 at 11:54 AM Joey Tran <joey.t...@schrodinger.com>
>>>>>> wrote:
>>>>>>
>>>>>>> After writing a few pipelines now, I keep getting tripped up from
>>>>>>> accidentally have duplicate labels from using multiple of the same
>>>>>>> transforms without labeling them. I figure this must be a common 
>>>>>>> complaint,
>>>>>>> so I was just curious, what the rationale behind this design was? My 
>>>>>>> naive
>>>>>>> thought off the top of my head is that it'd be more user friendly to 
>>>>>>> just
>>>>>>> auto increment duplicate transforms, but I figure I must be missing
>>>>>>> something
>>>>>>>
>>>>>>> Cheers,
>>>>>>> Joey
>>>>>>>
>>>>>>

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