Bump on this. Sorry to pester - I'm trying to get a few teams to adopt Apache Beam at my company and I'm trying to foresee parts of the API they might find inconvenient.
If there's a conclusion to make the behavior similar to java, I'm happy to put up a PR On Thu, Oct 5, 2023, 12:49 PM Joey Tran <joey.t...@schrodinger.com> wrote: > Is it really toggleable in Java? I imagine that if it's a toggle it'd be a > very sticky toggle since it'd be easy for PTransforms to accidentally rely > on it. > > On Thu, Oct 5, 2023 at 12:33 PM Robert Bradshaw <rober...@google.com> > wrote: > >> Huh. This used to be a hard error in Java, but I guess it's togglable >> with an option now. We should probably add the option to toggle Python too. >> (Unclear what the default should be, but this probably ties into >> re-thinking how pipeline update should work.) >> >> On Thu, Oct 5, 2023 at 4:58 AM Joey Tran <joey.t...@schrodinger.com> >> wrote: >> >>> Makes sense that the requirement is the same, but is the label >>> auto-generation behavior the same? I modified the BeamJava >>> wordcount example[1] to do the regex filter twice in a row, and unlike the >>> BeamPython example I posted before, it just warns instead of throwing an >>> exception. >>> >>> Tangentially, is it expected that the Beam playground examples don't >>> have a way to see the outputs of a run example? I have a vague memory that >>> there used to be a way to navigate to an output file after it's generated >>> but not sure if I just dreamt that up. Playing with the examples, I wasn't >>> positive if my runs were actually succeeding or not based on the stdout >>> alone. >>> >>> [1] https://play.beam.apache.org/?sdk=java&shared=mI7WUeje_r2 >>> <https://play.beam.apache.org/?sdk=java&shared=mI7WUeje_r2> >>> [2] https://play.beam.apache.org/?sdk=python&shared=hIrm7jvCamW >>> >>> On Wed, Oct 4, 2023 at 12:16 PM Robert Bradshaw via user < >>> user@beam.apache.org> wrote: >>> >>>> BeamJava and BeamPython have the exact same behavior: transform names >>>> within must be distinct [1]. This is because we do not necessarily know at >>>> pipeline construction time if the pipeline will be streaming or batch, or >>>> if it will be updated in the future, so the decision was made to impose >>>> this restriction up front. Both will auto-generate a name for you if one is >>>> not given, but will do so deterministically (not depending on some global >>>> context) to avoid potential update problems. >>>> >>>> [1] Note that this applies to the fully qualified transform name, so >>>> the naming only has to be distinct within a composite transform (or at the >>>> top level--the pipeline itself is isomorphic to a single composite >>>> transform). >>>> >>>> On Wed, Oct 4, 2023 at 3:43 AM Joey Tran <joey.t...@schrodinger.com> >>>> wrote: >>>> >>>>> Cross posting this thread to dev@ to see if this is intentional >>>>> behavior or if it's something worth changing for the python SDK >>>>> >>>>> On Tue, Oct 3, 2023, 10:10 PM XQ Hu via user <user@beam.apache.org> >>>>> wrote: >>>>> >>>>>> 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 >>>>>>>>>>>>> >>>>>>>>>>>>
