make microbatch models skippable

[MichelleArk]

Resolves #11021

Problem

1. Skipping microbatch model fails with typeError: object of type 'Field' has no len()
2. That codepath indicates the microbatch model is still running in some capacity

Solution

1. Stop using field(default_factory=...) outside a dataclass (MicrobatchModelRunner)
2. Return results early if initial microbatch run results in a skipped result

Checklist

• I have read the contributing guide and understand what's expected of me.
• I have run this code in development, and it appears to resolve the stated issue.
• This PR includes tests, or tests are not required or relevant for this PR.
• This PR has no interface changes (e.g., macros, CLI, logs, JSON artifacts, config files, adapter interface, etc.) or this PR has already received feedback and approval from Product or DX.
• This PR includes type annotations for new and modified functions.

🎩

Invoking dbt with ['run']
16:21:04  Running with dbt=1.9.0-b4
16:21:04  Registered adapter: postgres=1.9.0-b1
16:21:04  Unable to do partial parsing because saved manifest not found. Starting full parse.
16:21:05  Found 2 models, 429 macros
16:21:05  
16:21:05  Concurrency: 4 threads (target='default')
16:21:05  
16:21:05  1 of 2 START sql table model test17322060642773181458_test_microbatch.input_model  [RUN]
16:21:05  1 of 2 ERROR creating sql table model test17322060642773181458_test_microbatch.input_model  [ERROR in 0.05s]
16:21:05  2 of 2 SKIP relation test17322060642773181458_test_microbatch.microbatch_model . [SKIP]
16:21:05  
16:21:05  Finished running 1 incremental model, 1 table model in 0 hours 0 minutes and 0.55 seconds (0.55s).
16:21:05  
16:21:05  Completed with 1 error, 0 partial successs, and 0 warnings:
16:21:05  
16:21:05    Database Error in model input_model (models/input_model.sql)
  column "invalid" does not exist
  LINE 14: select invalid as event_time
                  ^
  compiled code at target/run/test/models/input_model.sql
16:21:05  

(extra '.' in skip result is a general issue, not just for microbatch models)

[github-actions]

Thank you for your pull request! We could not find a changelog entry for this change. For details on how to document a change, see the contributing guide.

[MichelleArk]

Usage of field(default_factory=...) was invalid outside of a dataclass

[QMalcolm]

Have we verified that having it set as batches: Dict[int, BatchType] = {} doesn't make it so two instances of MicrobatchModelRunner share the same underlying dict?

[QMalcolm]

Did a test. We do indeed need to do something different

>>> class MyClass:
...   batches = {}
... 
>>> instance1 = MyClass()
>>> instance2 = MyClass()
>>> instance1.batches
{}
>>> instance2.batches
{}
>>> instance1.batches['catch_phrase'] = "I like cats!"
>>> instance1.batches
{'catch_phrase': 'I like cats!'}
>>> instance2.batches
{'catch_phrase': 'I like cats!'}

[MichelleArk]

Good call. Fixed with init override:

>>> class MyClass:
...   def __init__(self):
...     self.batches = {}
...
>>> instance1 = MyClass()
>>> instance2 = MyClass()
>>> instance1.batches
{}
>>> instance2.batches
{}
>>> instance1.batches['catch_phrase'] = "I like cats!"
>>> instance1.batches
{'catch_phrase': 'I like cats!'}
>>> instance2.batches
{}
>>>

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 89.08%. Comparing base (fd6ec71) to head (052d699).
Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #11020      +/-   ##
==========================================
- Coverage   89.14%   89.08%   -0.07%     
==========================================
  Files         183      183              
  Lines       23760    23764       +4     
==========================================
- Hits        21182    21171      -11     
- Misses       2578     2593      +15     

Flag	Coverage Δ
integration	86.39% <100.00%> (-0.14%)	⬇️
unit	62.17% <75.00%> (+0.04%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
Unit Tests	62.17% <75.00%> (+0.04%)	⬆️
Integration Tests	86.39% <100.00%> (-0.14%)	⬇️

---- 🚨 Try these New Features:

• Flaky Tests Detection - Detect and resolve failed and flaky tests

[QMalcolm]