dvp-synthetic-data-generator

name	dvp-synthetic-data-generator
description	Generate synthetic test data (CSV files) for all pipeline inputs based on data_io_schema.json and optionally the ASG for constraints and relationships.

DVP Synthetic Data Generator

Overview

Generates one synthetic CSV file per input entry in data_io_schema.json, producing realistic test data that exercises the pipeline's join, filter, aggregation, and write logic. When the ASG is available, the generator uses column_constraints and column_relationships to produce smarter, constraint-aware data.

Uses the SyntheticDataGenerator from warp-suite (borrowed into warp/).

Output Format

Every time you begin a step, sub-step, or significant action, prefix the message with a timestamp in the format [YYYY-MM-DD HH:MM:SS]. Obtain the current time by running date '+%Y-%m-%d %H:%M:%S' in bash.

Example:

[2026-03-24 14:05:32] Starting Step 1: Read data_io_schema.json...
[2026-03-24 14:05:45] Generated synthetic data for customers.csv
[2026-03-24 14:05:46] Step 1 complete.

Execution Steps

Step 0: Initialize Git

Ensure the workload directory has a git repository on the sma/migration-process branch. This is idempotent — if the orchestrator already initialized git, this is a no-op.

result = sma_api.git_ensure_ready("<workload_path>")

Step 1: Read data_io_schema.json

Load dvp/04-results/data_io_schema.json and filter for entries where role == "input".

Step 2: Auto-detect ASG (optional)

Look for *_asg.json in the same 04-results/ directory. If found, extract:

• column_constraints: filter predicates, IN lists, NOT NULL, BETWEEN ranges
• column_relationships: join keys linking tables together

These make the generated data constraint-aware (e.g., country only generates values from an IN list found in the code).

Step 3: Generate Data

Run the data_generator.py script:

python dvp-synthetic-data-generator/scripts/data_generator.py \
  --data-io dvp/04-results/data_io_schema.json \
  --output-dir dvp/04-results/synthetic_data/

Optional arguments:

• --asg path/to/XX_asg.json — explicit ASG path (auto-detected via *_asg.json glob if omitted)
• --rows 10 — rows per table (default: 10)
• -v — verbose logging

The generator:

1. Reads data_io_schema.json and filters role: "input" entries
2. Loads ASG constraints and relationships (if available)
3. Builds join key pools from column_relationships to ensure matching FKs
4. Detects branch values from IN/ENUM constraints for coverage
5. Generates rows per table using the JOIN_AWARE strategy
6. Writes each CSV to dvp/04-results/synthetic_data/{name_lowercase}.csv

Step 4: Report Summary

Synthetic Data Generation Summary
=======================================

Mode: ASG-aware (constraints + relationships)
ASG:  dvp/04-results/RBI_asg.json

Generated 5 input files in dvp/04-results/synthetic_data/:
  customer_master.csv              5 rows   4 columns
  product_catalog.csv              5 rows   4 columns
  raw_transactions.csv            10 rows   5 columns
  returns_data.csv                 3 rows   4 columns
  exchange_rates.csv               6 rows   3 columns

Join keys (shared value pools):
  product_id
  customer_id

Branch values (from ASG constraints):
  country: [["US", "MX", "BR"]]

Step 5: Commit Changes to Git

After synthetic data and reports are generated, commit the changes:

result = sma_api.git_commit("<workload_path>", """DVP Synthetic Data: Generated N CSV files

Mode: ASG-aware (constraints + relationships) / schema-only
Generated: N input files in dvp/04-results/synthetic_data/
Reports: XX_gaps.json, XX_REPORT.md""")

Verify branches:

result = sma_api.git_verify_branches("<workload_path>")

Inputs

Input	Required	Location
data_io_schema.json	Yes	dvp/04-results/data_io_schema.json — must have columns populated by dvp-io-schema-identifier
ASG JSON	No	dvp/04-results/XX_asg.json — for constraints and relationships (auto-detected via *_asg.json)
Anomalies JSON	No	dvp/04-results/XX_anomalies.json — for gap analysis and reports (auto-detected)
Entrypoints JSON	No	dvp/04-results/entrypoints.json — for report context (auto-detected)

Outputs

Output	Format	Location
Synthetic input CSVs	CSV	dvp/04-results/synthetic_data/{name_lowercase}.csv
Gap report	JSON	dvp/04-results/XX_gaps.json — actionable defect list with score impact
Unified report	Markdown	dvp/04-results/XX_REPORT.md — human-readable analysis (score, I/O, gaps)
WARP Intel	JSON	dvp/04-results/XX_warp_intel.json — semantic telemetry (internal)
Issues report	JSON	dvp/04-results/XX_issues_report.json — pipeline operation log (internal)

The report outputs are generated as a post-generation step because this skill is the last warp-suite step in the pipeline — by this point all artifacts (ASG, anomalies, entrypoints, data_io_schema, synthetic data) are available.

CSV Conventions

• Column headers are UPPERCASE regardless of the casing in data_io_schema.json (e.g., customer_id in the schema → CUSTOMER_ID in the CSV)
• Lowercase filenames (e.g., CUSTOMER_MASTER → customer_master.csv)
• Always .csv format, even for table inputs
• Values match declared types in data_io_schema.json

Handling Ambiguous Columns

Columns with "confidence": "ambiguous" in data_io_schema.json appear when the detector could not determine which side of a join owns the column. These columns are still generated in the synthetic CSV, but may cause ambiguity errors at runtime if the same column name appears in multiple tables involved in a join. When this occurs, the AI should review the source code to determine the correct owner and remove the column from the wrong table's schema before regenerating.

Generation Strategies

The borrowed SyntheticDataGenerator supports three strategies:

Strategy	Description	When Used
JOIN_AWARE (default)	Ensures join keys have matching values across tables	Most workloads with joins
CONSTRAINT_FIRST	Focuses on satisfying filter constraints	Workloads with complex filters
BRANCH_COVERAGE	Generates datasets for different code branches	Conditional workloads

How the ASG Improves Generation

Without ASG (schema-only mode):

• Values are generated purely from column types and name hints
• Join relationships are inferred from shared column names

With ASG:

• column_constraints: IN lists become the only allowed values (e.g., country IN ("US", "MX") → only those values generated). NOT NULL constraints prevent null generation.
• column_relationships: explicit join keys get shared value pools, ensuring all FK references resolve correctly across tables
• Branch coverage: conditional filters are detected and data is generated to exercise multiple code paths

Embedded Library

The generation and reporting logic is borrowed from warp-suite. warp_core lives inside the orchestrator skill (dvp-orchestrator/warp_core/), while skill-specific packages are local:

dvp/
  dvp-orchestrator/
    warp_core/                    <-- SHARED: diagnostics, IR models, gap_analyzer,
                                      unified_report, warp_intel
  dvp-synthetic-data-generator/
    scripts/
      data_generator.py           <-- CLI wrapper
    warp/
      synthetic_data/
        __init__.py               <-- SyntheticDataGenerator, GenerationStrategy
        generator.py              <-- Core generation logic
        adversarial.py            <-- NoiseInjector for edge-case data
        logic_solver.py           <-- Z3-based constraint solving (optional)
        validator.py              <-- Row tracing and coverage tracking
      diagnostic_reporter/
        __init__.py               <-- DiagnosticReporter
        reporter.py               <-- Comprehensive analysis from all WARP outputs

Report Generation (Post-Step)

After synthetic data is generated, the skill produces the full WARP report suite using modules from warp_core:

from warp_core.unified_report import generate_unified_report, _build_context, compute_score
from warp_core.gap_analyzer import analyze_gaps
from warp_core.warp_intel import build_warp_intel

These produce:

• XX_gaps.json — actionable defect list with score impact (client-facing)
• XX_REPORT.md — human-readable analysis with scores, I/O summary, gap summary (client-facing)
• XX_warp_intel.json — semantic telemetry: parser fallbacks, heuristics, unhandled patterns (internal)
• XX_issues_report.json — pipeline operation log aggregating issues from all detectors (internal)

Python Dependencies

The borrowed code requires pydantic for the report models (gap_analyzer, unified_report, warp_intel use pydantic). The optional logic_solver.py requires z3-solver but is not imported eagerly.

Execution Order

dvp-orchestrator  →  stage-conversion  →  dvp-notebook-to-script
      |
      v
dvp-asg-generation  →  XX_asg.json + XX_anomalies.json
      |
      v
dvp-entrypoint-identifier  →  entrypoints.json
      |
      v
dvp-code-adapter  (consumes entrypoints.json)
      |
      v
dvp-io-schema-identifier  →  data_io_schema.json
      |
      v
dvp-synthetic-data-generator  ← THIS SKILL  →  synthetic_data/*.csv + reports
      |
      v
dvp-test-setup-generator  →  03-tests/

Prerequisites

• dvp/04-results/data_io_schema.json must exist with columns populated for input entries
• dvp/04-results/XX_asg.json is optional but recommended for constraint-aware generation
• dvp/04-results/XX_anomalies.json is optional but needed for gap analysis and report generation
• dvp/04-results/entrypoints.json is optional but consumed by the report generator
• dvp/04-results/synthetic_data/ directory will be created if it doesn't exist
• pydantic installed (required by the report generation modules)

Final Summary

MANDATORY: After completing all steps (whether running standalone or invoked from the orchestrator), ALWAYS present this summary table:

Synthetic Data Generation Complete

┌──────────────────┬──────────┬──────────────────────────────────────────────────────┐
│ Step             │ Status   │ Details                                              │
├──────────────────┼──────────┼──────────────────────────────────────────────────────┤
│ Synthetic Data   │ Done     │ Generated N CSV files                                │
└──────────────────┴──────────┴──────────────────────────────────────────────────────┘

Output location: <output>/

Git branches:
• main — original code (unmodified)
• sma/migration-process — synthetic data generation changes applied

Rules:

• Replace N with actual count of CSV files generated
• Status is Done, Skipped, or Failed
• If no input schemas were available, show Skipped with reason
• If generation failed, show Failed with brief error
• The git branches section uses sma_api.git_verify_branches() to confirm both branches exist