±1 for the named apply On Thu, Jun 23, 2016, 07:07 Robert Bradshaw <[email protected]> wrote:
> +1, I think it makes more sense to name the application of a transform > rather than the transform itself. (Still mulling on how best to do > this with Python...) > > On Wed, Jun 22, 2016 at 9:27 PM, Jean-Baptiste Onofré <[email protected]> > wrote: > > +1 > > > > Regards > > JB > > > > > > On 06/23/2016 12:17 AM, Ben Chambers wrote: > >> > >> Based on a recent PR (https://github.com/apache/incubator-beam/pull/468) > I > >> was reminded of the confusion around the use of > >> .apply(transform.named(someName)) and .apply(someName, transform). This > is > >> one of things I’ve wanted to cleanup for a while. I’d like to propose a > >> path towards removing this redundancy. > >> > >> First, some background -- why are there two ways to name things? When we > >> added support for updating existing pipelines, we needed all > applications > >> to have unique user-provided names to allow diff’ing the pipelines. We > >> found a few problems with the first approach -- using .named() to > create a > >> new transform -- which led to the introduction of the named apply: > >> > >> 1. When receiving an error about an application not having a name, it is > >> not obvious that a name should be given to the *transform* > >> 2. When using .named() to construct a new transform either the type > >> information is lost or the composite transform has to override .named() > >> > >> We now generally suggest the use of .apply(someName, transform). It is > >> easier to use and doesn’t lead to as much confusion around PTransform > >> names > >> and PTransform application names. > >> > >> To that end, I'd like to propose the following changes to the code and > >> documentation: > >> 1. Replace the usage of .named(name) in all examples and composites with > >> the named-apply syntax. > >> 2. Replace .named(name) with a protected PTransform constructor which > >> takes > >> a default name. If not provided, the default name will be derived from > the > >> class of the PTransform. > >> 3. Use the protected constructor in composites (where appropriate) to > >> ensure that the default application has a reasonable name. > >> > >> Users will benefit from having a single way of naming applications while > >> building a pipeline. Any breakages due to the removal of .named should > be > >> easily fixed by either using the named application or by passing the > name > >> to the constructor of a composite. > >> > >> I’d like to hear any comments or opinions on this topic from the wider > >> community. Please let me know what you think! > >> > >> -- Ben > >> > > > > -- > > Jean-Baptiste Onofré > > [email protected] > > http://blog.nanthrax.net > > Talend - http://www.talend.com >
