[DRAFT] Early stages / PoC of Distributed Data Movement with Gobblin-on-Temporal

[phet]

Dear Gobblin maintainers,

Please accept this PR. I understand that it will not be reviewed until I have checked off all the steps below!

JIRA

• My PR addresses the following Gobblin JIRA issues and references them in the PR title. For example, "[GOBBLIN-XXX] My Gobblin PR"
  • https://issues.apache.org/jira/browse/GOBBLIN-XXX

Description

• Here are some details about my PR, including screenshots (if applicable):

ATTENTION: This PR is currently only for illustration and sharing ideas. I plan to continue iterating and then prepare the commits individually for merge.

1. Adjust Gobblin-Temporal configurability for consistency and abstraction
2. Define Workload abstraction for Temporal workflows of unbounded size through sub-workflow nesting
3. Add gobblin-temporal load generator for a single subsuming super-workflow with many activities nested beneath
4. Implement early pieces of Distributed Data Movement (DDM) w/ Gobblin-on-Temporal WorkUnit evaluation

Tests

• My PR adds the following unit tests OR does not need testing for this extremely good reason:

manual execution for both Load-Gen and DDM via Temporal-workers-on-YARN

Commits

• My commits all reference JIRA issues in their subject lines, and I have squashed multiple commits if they address the same issue. In addition, my commits follow the guidelines from "How to write a good git commit message":
  1. Subject is separated from body by a blank line
  2. Subject is limited to 50 characters
  3. Subject does not end with a period
  4. Subject uses the imperative mood ("add", not "adding")
  5. Body wraps at 72 characters
  6. Body explains "what" and "why", not "how"