MOB-53647 Aggregator: propagate extend-aggregation to nested underlings

[devership16]

Summary

Fixes ValueError: substring not found crash in __extend_reported_data when extend-aggregation: true is enabled for BBT (selenium) tests.

Root Cause

ApiritifLoadReader extends ConsolidatingAggregator and is added as an underling of the outer ConsolidatingAggregator. The chain:

Outer ConsolidatingAggregator (engine module, startup() called)
  └── ApiritifLoadReader (inner ConsolidatingAggregator, startup() NOT called)
       └── JTLReader (reads CSV samples)

The outer's startup() propagates _redundant_aggregation=True to the inner via set_aggregation(). But the inner's startup() is never called by the engine (it's just an underling, not a module). So the inner never propagates the flag to its underlings (JTLReader).

Without the flag, JTLReader's __add_sample skips get_mixed_label(), producing raw labels like "Navigate to site" without the required -state suffix. When the outer's converter runs __extend_reported_data, key.rindex('-') raises ValueError.

Fix

set_aggregation() now recursively propagates to nested underlings:

def set_aggregation(self, aggregation):
    self._redundant_aggregation = aggregation
    for underling in getattr(self, 'underlings', []):
        underling.set_aggregation(aggregation)

No risk of infinite loop — the underling tree is a DAG (directed acyclic graph). Leaf nodes like JTLReader have underlings = [], so recursion terminates. Underlings never reference their parent, so no cycles are possible.

Test plan

• test_nested_aggregator_propagates_extend_aggregation — verifies flag propagation and mixed labels
• All 19 existing consolidating aggregator tests pass

Companion fix: Blazemeter/a.blazemeter.com#8329 (allows BBT executors in isTransactionFilterAllowed)

🤖 Generated with Claude Code

[Copilot]

🟢 Approval recommended

The change is narrowly scoped, matches the stated root cause, and is covered by a targeted regression test.

Pull request overview

This PR fixes a crash in Taurus’ ConsolidatingAggregator when extend-aggregation: true is used in nested aggregation setups (e.g., outer engine aggregator → ApiritifLoadReader → JTLReader). The core change ensures the “redundant aggregation” flag is propagated recursively so nested readers generate mixed labels with the expected -state suffix, preventing ValueError in __extend_reported_data.

Changes:

• Recursively propagate set_aggregation() to nested underlings so inner aggregators forward the flag to their own readers.
• Add a unit test that constructs an outer→inner→reader chain and asserts flag propagation and -state suffixed labels.

File summaries

File	Description
bzt/modules/aggregator.py	Makes ResultsProvider.set_aggregation() propagate the flag through nested underlings, fixing the crash scenario.
tests/unit/modules/test_consolidatingAggregator.py	Adds regression coverage for nested-aggregator propagation and mixed-label generation.

Review details

• Files reviewed: 2/2 changed files
• Comments generated: 0
• Review effort level: Lite

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.19%. Comparing base (806cb89) to head (ef3dce3).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2022      +/-   ##
==========================================
+ Coverage   88.19%   88.19%   +0.01%     
==========================================
  Files          75       75              
  Lines       21162    21164       +2     
==========================================
+ Hits        18661    18663       +2     
  Misses       2501     2501              

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