Similar point here to the other ideas that are popping up. Maybe we should just focus on completing 2.0 and make all discussions about further improvements to 2.1? While those are important discussions (and we should continue them in the near future !) I think at this point focusing on delivering 2.0 in its current shape should be our focus now ?
J. On Thu, Jun 18, 2020 at 6:35 PM Xinbin Huang <bin.huan...@gmail.com> wrote: > Hi Daniel > > I agree that the TaskGroup should have the same API as a DAG object related > to task dependencies, but it will not have anything related to actual > execution or scheduling. > I will update the AIP according to this over the weekend. > > > We could even make a “DAGTemplate” object s.t. when you import the object > you can import it with parameters to determine the shape of the DAG. > > Can you elaborate a bit more on this? Does it serve a similar purpose as a > DAG factory function? > > > > On Thu, Jun 18, 2020 at 9:13 AM Daniel Imberman <daniel.imber...@gmail.com > > > wrote: > > > Hi Bin, > > > > Why not give the TaskGroup the same API as a DAG object (e.g. the bitwise > > operator fro task dependencies). We could even make a “DAGTemplate” > object > > s.t. when you import the object you can import it with parameters to > > determine the shape of the DAG. > > > > > > On Wed, Jun 17, 2020 at 8:54 PM, Xinbin Huang <bin.huan...@gmail.com> > > wrote: > > The TaskGroup will not take schedule interval as a parameter itself, and > it > > depends on the DAG where it attaches to. In my opinion, the TaskGroup > will > > only contain a group of tasks with interdependencies, and the TaskGroup > > behaves like a task. It doesn't contain any execution/scheduling logic > > (i.e. schedule_interval, concurrency, max_active_runs etc.) like a DAG > > does. > > > > > For example, there is the scenario that the schedule interval of DAG is > > 1 hour and the schedule interval of TaskGroup is 20 min. > > > > I am curious why you ask this. Is this a use case that you want to > achieve? > > > > Bin > > > > On Wed, Jun 17, 2020 at 7:59 PM 蒋晓峰 <thanosxnicho...@gmail.com> wrote: > > > > > Hi Bin, > > > Using TaskGroup, Is the schedule interval of TaskGroup the same as the > > > parent DAG? My main concern is whether the schedule interval of > TaskGroup > > > could be different with that of the DAG? For example, there is the > > scenario > > > that the schedule interval of DAG is 1 hour and the schedule interval > of > > > TaskGroup is 20 min. > > > > > > Cheers, > > > Nicholas > > > > > > On Thu, Jun 18, 2020 at 10:30 AM Xinbin Huang <bin.huan...@gmail.com> > > > wrote: > > > > > > > Hi Nicholas, > > > > > > > > I am not sure about the old behavior of SubDagOperator, maybe it will > > > throw > > > > an error? But in the original proposal, the subdag's > schedule_interval > > > will > > > > be ignored. Or if we decide to use TaskGroup to replace SubDag, there > > > will > > > > be no subdag schedule_interval. > > > > > > > > Bin > > > > > > > > On Wed, Jun 17, 2020 at 6:21 PM 蒋晓峰 <thanosxnicho...@gmail.com> > wrote: > > > > > > > > > Hi Bin, > > > > > Thanks for your good proposal. I was confused whether the schedule > > > > > interval of SubDAG is different from that of the parent DAG? I have > > > > > discussed with Jiajie Zhong about the schedule interval of SubDAG. > If > > > the > > > > > SubDagOperator has a different schedule interval, what will happen > > for > > > > the > > > > > scheduler to schedule the parent DAG? > > > > > > > > > > Regards, > > > > > Nicholas Jiang > > > > > > > > > > On Thu, Jun 18, 2020 at 8:04 AM Xinbin Huang < > bin.huan...@gmail.com> > > > > > wrote: > > > > > > > > > > > Thank you, Max, Kaxil, and everyone's feedback! > > > > > > > > > > > > I have rethought about the concept of subdag and task groups. I > > think > > > > the > > > > > > better way to approach this is to entirely remove subdag and > > > introduce > > > > > the > > > > > > concept of TaskGroup, which is a container of tasks along with > > their > > > > > > dependencies *without execution/scheduling logic as a DAG*. The > > only > > > > > > purpose of it is to group a list of tasks, but you still need to > > add > > > it > > > > > to > > > > > > a DAG for execution. > > > > > > > > > > > > Here is a small code snippet. > > > > > > > > > > > > ``` > > > > > > class TaskGroup: > > > > > > """ > > > > > > A TaskGroup contains a group of tasks. > > > > > > > > > > > > If default_args is missing, it will take default args from the > > > DAG. > > > > > > """ > > > > > > def __init__(self, group_id, default_args): > > > > > > pass > > > > > > > > > > > > > > > > > > """ > > > > > > You can add tasks to a task group similar to adding tasks to a > DAG > > > > > > > > > > > > This can be declared in a separate file from the dag file > > > > > > """ > > > > > > download_group = TaskGroup(group_id='download', > > > > > default_args=default_args) > > > > > > download_group.add_task(task1) > > > > > > task2.dag = download_group > > > > > > > > > > > > with download_group: > > > > > > task3 = DummyOperator(task_id='task3') > > > > > > > > > > > > [task, task2] >> task3 > > > > > > > > > > > > > > > > > > """Add it to a DAG for execution""" > > > > > > with DAG(dag_id='start_download_dag', default_args=default_args, > > > > > > schedule_interval='@daily', ...) as dag: > > > > > > start = DummyOperator(task_id='start') > > > > > > start >> download_group > > > > > > # this is equivalent to > > > > > > # start >> [task, task2] >> task3 > > > > > > ``` > > > > > > > > > > > > With this, we can still reuse a group of tasks and set > dependencies > > > > > between > > > > > > them; it avoids the boilerplate code from using SubDagOperator, > and > > > we > > > > > can > > > > > > declare dependencies as `task >> task_group >> task`. > > > > > > > > > > > > User migration wise, we can introduce it before Airflow 2.0 and > > allow > > > > > > gradual transition. Then we can decide if we still want to keep > the > > > > > > SubDagOperator or simply remove it. > > > > > > > > > > > > Any thoughts? > > > > > > > > > > > > Cheers, > > > > > > Bin > > > > > > > > > > > > > > > > > > On Wed, Jun 17, 2020 at 7:37 AM Maxime Beauchemin < > > > > > > maximebeauche...@gmail.com> wrote: > > > > > > > > > > > > > +1, proposal looks good. > > > > > > > > > > > > > > The original intention was really to have tasks groups and a > > > > > zoom-in/out > > > > > > in > > > > > > > the UI. The original reasoning was to reuse the DAG object > since > > it > > > > is > > > > > a > > > > > > > group of tasks, but as highlighted here it does create > underlying > > > > > > > confusions since a DAG is much more than just a group of tasks. > > > > > > > > > > > > > > Max > > > > > > > > > > > > > > On Mon, Jun 15, 2020 at 2:43 AM Poornima Joshi < > > > > > > joshipoornim...@gmail.com> > > > > > > > wrote: > > > > > > > > > > > > > > > Thank you for your email. > > > > > > > > > > > > > > > > On Sat, Jun 13, 2020 at 12:18 AM Xinbin Huang < > > > > bin.huan...@gmail.com > > > > > > > > > > > > > > wrote: > > > > > > > > > > > > > > > > > > > - *Unpack SubDags during dag parsing*: This rewrites > the > > > > > > > > > *DagBag.bag_dag* > > > > > > > > > > > method to unpack subdag while parsing, and it will > give a > > > > > flat > > > > > > > > > > > structure at > > > > > > > > > > > the task level > > > > > > > > > > > > > > > > > > > > The serialized_dag representation already does this I > > think. > > > At > > > > > > least > > > > > > > > if > > > > > > > > > > I've understood your idea here correctly. > > > > > > > > > > > > > > > > > > I am not sure about serialized_dag representation, but at > > least > > > > it > > > > > > will > > > > > > > > > still keep the subdag entry in the DAG table? In my > proposal > > as > > > > > also > > > > > > in > > > > > > > > the > > > > > > > > > draft PR, the idea is to *extract the tasks from the subdag > > and > > > > add > > > > > > > them > > > > > > > > > back to the root_dag. *So the runtime DAG graph will look > > > exactly > > > > > the > > > > > > > > > same as without subdag but with metadata attached to those > > > > > sections. > > > > > > > > These > > > > > > > > > metadata will be later on used to render in the UI. So > after > > > > > parsing > > > > > > ( > > > > > > > > > *DagBag.process_file()*), it will just output the *root_dag > > > > > *instead > > > > > > of > > > > > > > > *root_dag + > > > > > > > > > subdag + subdag + nested subdag* etc. > > > > > > > > > > > > > > > > > > - e.g. section-1-* will have metadata > > > current_group=section-1, > > > > > > > > > parent_group=<the-root-dag-id> (welcome for naming > > > > suggestions), > > > > > > the > > > > > > > > > reason for parent_group is that we can have nested group > and > > > > > still > > > > > > > be > > > > > > > > > able to capture the dependency. > > > > > > > > > > > > > > > > > > Runtime DAG: > > > > > > > > > [image: image.png] > > > > > > > > > > > > > > > > > > While at the UI, what we see would be something like this > by > > > > > > utilizing > > > > > > > > the > > > > > > > > > metadata, and then we can expand or zoom into in some way. > > > > > > > > > [image: image.png] > > > > > > > > > > > > > > > > > > The benefits I can see is that: > > > > > > > > > 1. We don't need to deal with the extra complexity of > SubDag > > > for > > > > > > > > execution > > > > > > > > > and scheduling. It will be the same as not using SubDag. > > > > > > > > > 2. Still have the benefits of modularized and reusable dag > > code > > > > and > > > > > > > > > declare dependencies between them. And with the new > > > > SubDagOperator > > > > > > (see > > > > > > > > AIP > > > > > > > > > or draft PR), we can use the same dag_factory function for > > > > > > generating 1 > > > > > > > > > dag, a lot of dynamic dags, or used for SubDag (in this > case, > > > it > > > > > will > > > > > > > > just > > > > > > > > > extract all underlying tasks and append to the root dag). > > > > > > > > > > > > > > > > > > - Then it gets to the idea of replacing subdag with a > > > simpler > > > > > > > concept > > > > > > > > > by Ash: the proposed change basically drains out the > > > contents > > > > > of > > > > > > a > > > > > > > > SubDag > > > > > > > > > and becomes more like > > > > > ExtractSubdagTasksAndAppendToRootdagOperator > > > > > > > > (forgive > > > > > > > > > me about the crazy name..). In this case, it is still > > > > necessary > > > > > to > > > > > > > > keep the > > > > > > > > > concept of subdag as it is nothing more than a name? > > > > > > > > > > > > > > > > > > That's why the TaskGroup idea comes up. Thanks Chris Palmer > > for > > > > > > helping > > > > > > > > > conceptualize the functionality of TaskGroup, I will just > > paste > > > > it > > > > > > > here. > > > > > > > > > > > > > > > > > > > - Tasks can be added to a TaskGroup > > > > > > > > > > - You *can* have dependencies between Tasks in the same > > > > > TaskGroup, > > > > > > > but > > > > > > > > > > *cannot* have dependencies between a Task in a TaskGroup > > > and > > > > > > > either a > > > > > > > > > > Task in a different TaskGroup or a Task not in any group > > > > > > > > > > - You *can* have dependencies between a TaskGroup and > > > either > > > > > > other > > > > > > > > > > TaskGroups or Tasks not in any group > > > > > > > > > > - The UI will by default render a TaskGroup as a single > > > > > "object", > > > > > > > but > > > > > > > > > > which you expand or zoom into in some way > > > > > > > > > > - You'd need some way to determine what the "status" of a > > > > > > TaskGroup > > > > > > > > was > > > > > > > > > > at least for UI display purposes > > > > > > > > > > > > > > > > > > I agree with Chris: > > > > > > > > > - From the backend's view (scheduler & executor), I think > > > > TaskGroup > > > > > > > > should > > > > > > > > > be ignored during execution. (unless we decide to implement > > > some > > > > > > > metadata > > > > > > > > > operations that allows start/stop a group of tasks etc.) > > > > > > > > > - From the UI's View, it should be able to pick up the > > > individual > > > > > > > tasks' > > > > > > > > > status and then determine the TaskGroup's status > > > > > > > > > > > > > > > > > > Bin > > > > > > > > > > > > > > > > > > On Fri, Jun 12, 2020 at 10:28 AM Daniel Imberman < > > > > > > > > > daniel.imber...@gmail.com> wrote: > > > > > > > > > > > > > > > > > >> I hadn’t thought about using the `>>` operator to tie dags > > > > > together > > > > > > > but > > > > > > > > I > > > > > > > > >> think that sounds pretty great! I wonder if we could > > > essentially > > > > > > write > > > > > > > > in > > > > > > > > >> the ability to set dependencies to all starter-tasks for > > that > > > > DAG. > > > > > > > > >> > > > > > > > > >> I’m personally ok with SubDag being a mostly UI concept. > It > > > > > doesn’t > > > > > > > need > > > > > > > > >> to execute separately, you’re just adding more tasks to > the > > > > queue > > > > > > that > > > > > > > > will > > > > > > > > >> be executed when there are resources available. > > > > > > > > >> > > > > > > > > >> via Newton Mail [ > > > > > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > https://cloudmagic.com/k/d/mailapp?ct=dx&cv=10.0.50&pv=10.14.6&source=email_footer_2 > > > > > > > > >> ] > > > > > > > > >> On Fri, Jun 12, 2020 at 9:45 AM, Chris Palmer < > > > > ch...@crpalmer.com > > > > > > > > > > > > > > wrote: > > > > > > > > >> I agree that SubDAGs are an overly complex abstraction. I > > > think > > > > > what > > > > > > > is > > > > > > > > >> needed/useful is a TaskGroup concept. On a high level I > > think > > > > you > > > > > > want > > > > > > > > >> this > > > > > > > > >> functionality: > > > > > > > > >> > > > > > > > > >> - Tasks can be added to a TaskGroup > > > > > > > > >> - You *can* have dependencies between Tasks in the same > > > > TaskGroup, > > > > > > but > > > > > > > > >> *cannot* have dependencies between a Task in a TaskGroup > and > > > > > either > > > > > > a > > > > > > > > >> Task in a different TaskGroup or a Task not in any group > > > > > > > > >> - You *can* have dependencies between a TaskGroup and > either > > > > other > > > > > > > > >> TaskGroups or Tasks not in any group > > > > > > > > >> - The UI will by default render a TaskGroup as a single > > > > "object", > > > > > > but > > > > > > > > >> which you expand or zoom into in some way > > > > > > > > >> - You'd need some way to determine what the "status" of a > > > > > TaskGroup > > > > > > > was > > > > > > > > >> at least for UI display purposes > > > > > > > > >> > > > > > > > > >> Not sure if it would need to be a top level object with > its > > > own > > > > > > > database > > > > > > > > >> table and model or just another attribute on tasks. I > think > > > you > > > > > > could > > > > > > > > >> build > > > > > > > > >> it in a way such that from the schedulers point of view a > > DAG > > > > with > > > > > > > > >> TaskGroups doesn't get treated any differently. So it > really > > > > just > > > > > > > > becomes > > > > > > > > >> a > > > > > > > > >> shortcut for setting dependencies between sets of Tasks, > and > > > > > allows > > > > > > > the > > > > > > > > UI > > > > > > > > >> to simplify the render of the DAG structure. > > > > > > > > >> > > > > > > > > >> Chris > > > > > > > > >> > > > > > > > > >> On Fri, Jun 12, 2020 at 12:12 PM Dan Davydov > > > > > > > > <ddavy...@twitter.com.invalid > > > > > > > > >> > > > > > > > > > >> wrote: > > > > > > > > >> > > > > > > > > >> > Agree with James (and think it's actually the more > > important > > > > > issue > > > > > > > to > > > > > > > > >> fix), > > > > > > > > >> > but I am still convinced Ash' idea is the right way > > forward > > > > > (just > > > > > > it > > > > > > > > >> might > > > > > > > > >> > require a bit more work to deprecate than adding visual > > > > grouping > > > > > > in > > > > > > > > the > > > > > > > > >> > UI). > > > > > > > > >> > > > > > > > > > >> > There was a previous thread about this FYI with more > > context > > > > on > > > > > > why > > > > > > > > >> subdags > > > > > > > > >> > are bad and potential solutions: > > > > > > > > >> > > > > > > https://www.mail-archive.com/dev@airflow.apache.org/msg01202.html > > > > > > > . A > > > > > > > > >> > solution I outline there to Jame's problem is e.g. > > enabling > > > > the > > > > > >> > > > > > > > > >> operator > > > > > > > > >> > for Airflow operators to work with DAGs as well. I see > > this > > > > > being > > > > > > > > >> separate > > > > > > > > >> > from Ash' solution for DAG grouping in the UI but one of > > the > > > > two > > > > > > > items > > > > > > > > >> > required to replace all existing subdag functionality. > > > > > > > > >> > > > > > > > > > >> > I've been working with subdags for 3 years and they are > > > > always a > > > > > > > giant > > > > > > > > >> pain > > > > > > > > >> > to use. They are a constant source of user confusion and > > > > > breakages > > > > > > > > >> during > > > > > > > > >> > upgrades. Would love to see them gone :). > > > > > > > > >> > > > > > > > > > >> > On Fri, Jun 12, 2020 at 11:11 AM James Coder < > > > > > jcode...@gmail.com> > > > > > > > > >> wrote: > > > > > > > > >> > > > > > > > > > >> > > I'm not sure I totally agree it's just a UI concept. I > > use > > > > the > > > > > > > > subdag > > > > > > > > >> > > operator to simplify dependencies too. If you have a > > group > > > > of > > > > > > > tasks > > > > > > > > >> that > > > > > > > > >> > > need to finish before another group of tasks start, > > using > > > a > > > > > > subdag > > > > > > > > is > > > > > > > > >> a > > > > > > > > >> > > pretty quick way to set those dependencies and I think > > > also > > > > > make > > > > > > > it > > > > > > > > >> > easier > > > > > > > > >> > > to follow the dag code. > > > > > > > > >> > > > > > > > > > > >> > > On Fri, Jun 12, 2020 at 9:53 AM Kyle Hamlin < > > > > > > hamlin...@gmail.com> > > > > > > > > >> wrote: > > > > > > > > >> > > > > > > > > > > >> > > > I second Ash’s grouping concept. > > > > > > > > >> > > > > > > > > > > > >> > > > On Fri, Jun 12, 2020 at 5:10 AM Ash Berlin-Taylor < > > > > > > > a...@apache.org > > > > > > > > > > > > > > > > > >> > > wrote: > > > > > > > > >> > > > > > > > > > > > >> > > > > Question: > > > > > > > > >> > > > > > > > > > > > > >> > > > > Do we even need the SubDagOperator anymore? > > > > > > > > >> > > > > > > > > > > > > >> > > > > Would removing it entirely and just replacing it > > with > > > a > > > > UI > > > > > > > > >> grouping > > > > > > > > >> > > > > concept be conceptually simpler, less to get > wrong, > > > and > > > > > > closer > > > > > > > > to > > > > > > > > >> > what > > > > > > > > >> > > > > users actually want to achieve with subdags? > > > > > > > > >> > > > > > > > > > > > > >> > > > > With your proposed change, tasks in subdags could > > > start > > > > > > > running > > > > > > > > in > > > > > > > > >> > > > > parallel (a good change) -- so should we not also > > just > > > > > > > > _enitrely_ > > > > > > > > >> > > remove > > > > > > > > >> > > > > the concept of a sub dag and replace it with > > something > > > > > > > simpler. > > > > > > > > >> > > > > > > > > > > > > >> > > > > Problems with subdags (I think. I haven't used > them > > > > > > > extensively > > > > > > > > so > > > > > > > > >> > may > > > > > > > > >> > > > > be wrong on some of these): > > > > > > > > >> > > > > - They need their own dag_id, but it has(?) to be > of > > > the > > > > > > form > > > > > > > > >> > > > > `parent_dag_id.subdag_id`. > > > > > > > > >> > > > > - They need their own schedule_interval, but it > has > > to > > > > > match > > > > > > > the > > > > > > > > >> > parent > > > > > > > > >> > > > dag > > > > > > > > >> > > > > - Sub dags can be paused on their own. (Does it > make > > > > sense > > > > > > to > > > > > > > do > > > > > > > > >> > this? > > > > > > > > >> > > > > Pausing just a sub dag would mean the sub dag > would > > > > never > > > > > > > > >> execute, so > > > > > > > > >> > > > > the SubDagOperator would fail too. > > > > > > > > >> > > > > - You had to choose the executor to operator a > > subdag > > > > with > > > > > > -- > > > > > > > > >> always > > > > > > > > >> > a > > > > > > > > >> > > > > bit of a kludge. > > > > > > > > >> > > > > > > > > > > > > >> > > > > Thoughts? > > > > > > > > >> > > > > > > > > > > > > >> > > > > -ash > > > > > > > > >> > > > > > > > > > > > > >> > > > > On Jun 12 2020, at 12:01 pm, Ash Berlin-Taylor < > > > > > > > a...@apache.org> > > > > > > > > >> > wrote: > > > > > > > > >> > > > > > > > > > > > > >> > > > > > Workon sub-dags is much needed, I'm excited to > see > > > how > > > > > > this > > > > > > > > >> > > progresses. > > > > > > > > >> > > > > > > > > > > > > > >> > > > > > > > > > > > > > >> > > > > >> - *Unpack SubDags during dag parsing*: This > > > rewrites > > > > > the > > > > > > > > >> > > > > *DagBag.bag_dag* > > > > > > > > >> > > > > >> method to unpack subdag while parsing, and it > > will > > > > > give a > > > > > > > > flat > > > > > > > > >> > > > > >> structure at > > > > > > > > >> > > > > >> the task level > > > > > > > > >> > > > > > > > > > > > > > >> > > > > > The serialized_dag representation already does > > this > > > I > > > > > > think. > > > > > > > > At > > > > > > > > >> > least > > > > > > > > >> > > > if > > > > > > > > >> > > > > > I've understood your idea here correctly. > > > > > > > > >> > > > > > > > > > > > > > >> > > > > > -ash > > > > > > > > >> > > > > > > > > > > > > > >> > > > > > > > > > > > > > >> > > > > > On Jun 12 2020, at 9:51 am, Xinbin Huang < > > > > > > > > bin.huan...@gmail.com > > > > > > > > >> > > > > > > > > > >> > > > wrote: > > > > > > > > >> > > > > > > > > > > > > > >> > > > > >> Hi everyone, > > > > > > > > >> > > > > >> > > > > > > > > >> > > > > >> Sending a message to everyone and collect > > feedback > > > on > > > > > the > > > > > > > > >> AIP-34 > > > > > > > > >> > on > > > > > > > > >> > > > > >> rewriting SubDagOperator. This was previously > > > briefly > > > > > > > > >> mentioned in > > > > > > > > >> > > the > > > > > > > > >> > > > > >> discussion about what needs to be done for > > Airflow > > > > 2.0, > > > > > > and > > > > > > > > >> one of > > > > > > > > >> > > the > > > > > > > > >> > > > > >> ideas is to make SubDagOperator attach tasks > back > > > to > > > > > the > > > > > > > root > > > > > > > > >> DAG. > > > > > > > > >> > > > > >> > > > > > > > > >> > > > > >> This AIP-34 focuses on solving SubDagOperator > > > related > > > > > > > issues > > > > > > > > by > > > > > > > > >> > > > > reattaching > > > > > > > > >> > > > > >> all tasks back to the root dag while respecting > > > > > > > dependencies > > > > > > > > >> > during > > > > > > > > >> > > > > >> parsing. The original grouping effect on the UI > > > will > > > > be > > > > > > > > >> achieved > > > > > > > > >> > > > through > > > > > > > > >> > > > > >> grouping related tasks by metadata. > > > > > > > > >> > > > > >> > > > > > > > > >> > > > > >> This also makes the dag_factory function more > > > > reusable > > > > > > > > because > > > > > > > > >> you > > > > > > > > >> > > > don't > > > > > > > > >> > > > > >> need to have parent_dag_name and child_dag_name > > in > > > > the > > > > > > > > function > > > > > > > > >> > > > > signature > > > > > > > > >> > > > > >> anymore. > > > > > > > > >> > > > > >> > > > > > > > > >> > > > > >> Changes proposed: > > > > > > > > >> > > > > >> > > > > > > > > >> > > > > >> - *Unpack SubDags during dag parsing*: This > > > rewrites > > > > > the > > > > > > > > >> > > > > *DagBag.bag_dag* > > > > > > > > >> > > > > >> method to unpack subdag while parsing, and it > > will > > > > > give a > > > > > > > > flat > > > > > > > > >> > > > > >> structure at > > > > > > > > >> > > > > >> the task level > > > > > > > > >> > > > > >> - *Simplify SubDagOperator*: The new > > SubDagOperator > > > > > acts > > > > > > > > like a > > > > > > > > >> > > > > >> container and most of the original methods are > > > > removed. > > > > > > The > > > > > > > > >> > > > > >> signature is > > > > > > > > >> > > > > >> also changed to *subdag_factory *with > > *subdag_args > > > > *and > > > > > > > > >> > > > > *subdag_kwargs*. > > > > > > > > >> > > > > >> This is similar to the PythonOperator > signature. > > > > > > > > >> > > > > >> - *Add a TaskGroup model and add current_group > & > > > > > > > parent_group > > > > > > > > >> > > > > attributes > > > > > > > > >> > > > > >> to BaseOperator*: This metadata is used to > group > > > > tasks > > > > > > for > > > > > > > > >> > > > > >> rendering at > > > > > > > > >> > > > > >> UI level. It may potentially extend further to > > > group > > > > > > > > arbitrary > > > > > > > > >> > > tasks > > > > > > > > >> > > > > >> outside the context of subdag to allow > > group-level > > > > > > > operations > > > > > > > > >> > > (i.e. > > > > > > > > >> > > > > >> stop/trigger a group of task within the dag) > > > > > > > > >> > > > > >> - *Webserver UI for SubDag*: Proposed UI > > > modification > > > > > to > > > > > > > > allow > > > > > > > > >> > > > > >> (un)collapse a group of tasks for a flat > > structure > > > to > > > > > > pair > > > > > > > > with > > > > > > > > >> > > the > > > > > > > > >> > > > > first > > > > > > > > >> > > > > >> change instead of the original hierarchical > > > > structure. > > > > > > > > >> > > > > >> > > > > > > > > >> > > > > >> > > > > > > > > >> > > > > >> Please see related documents and PRs for > details: > > > > > > > > >> > > > > >> AIP: > > > > > > > > >> > > > > >> > > > > > > > > >> > > > > > > > > > > > > >> > > > > > > > > > > > >> > > > > > > > > > > >> > > > > > > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > https://cwiki.apache.org/confluence/display/AIRFLOW/AIP-34+Rewrite+SubDagOperator > > > > > > > > >> > > > > >> > > > > > > > > >> > > > > >> Original Issue: > > > > > > > > https://github.com/apache/airflow/issues/8078 > > > > > > > > >> > > > > >> Draft PR: > > > > https://github.com/apache/airflow/pull/9243 > > > > > > > > >> > > > > >> > > > > > > > > >> > > > > >> Please let me know if there are any aspects > that > > > you > > > > > > > > >> > agree/disagree > > > > > > > > >> > > > > >> with or > > > > > > > > >> > > > > >> need more clarification (especially the third > > > change > > > > > > > > regarding > > > > > > > > >> > > > > TaskGroup). > > > > > > > > >> > > > > >> Any comments are welcome and I am looking > forward > > > to > > > > > it! > > > > > > > > >> > > > > >> > > > > > > > > >> > > > > >> Cheers > > > > > > > > >> > > > > >> Bin > > > > > > > > >> > > > > >> > > > > > > > > >> > > > > > > > > > > > > >> > > > -- > > > > > > > > >> > > > Kyle Hamlin > > > > > > > > >> > > > > > > > > > > > >> > > > > > > > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -- > > > > > > > > Thanks & Regards > > > > > > > > Poornima > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -- Jarek Potiuk Polidea <https://www.polidea.com/> | Principal Software Engineer M: +48 660 796 129 <+48660796129> [image: Polidea] <https://www.polidea.com/>
