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Data Contract Framework — Implementation Guide

#data #databricks #azure #dataengineering

Data Contract Framework — Implementation Guide

Datanest Digital — datanest.dev

Overview

This guide walks you through deploying the Data Contract Framework in your
Databricks environment. By the end, you will have:

  • A YAML-based contract specification for every critical dataset
  • Automated contract generation from existing tables
  • Continuous SLA monitoring with alerting
  • Breaking change detection in your CI/CD pipeline
  • A searchable contract registry with version history
  • Compliance dashboards for executive visibility

Prerequisites

  • Databricks workspace with Unity Catalog enabled
  • Databricks Runtime 13.0 or later
  • Python 3.9+
  • A dedicated governance schema (e.g., main.data_governance)
  • Git repository for contract version control

Phase 1: Foundation (Days 1-3)

Step 1: Create the Governance Schema 

CREATE SCHEMA IF NOT EXISTS main.data_governance
COMMENT 'Data contract registry, SLA monitoring, and compliance metrics.';
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Step 2: Initialize the Contract Registry

Upload registry/contract_registry.py to your Databricks workspace, then run:

from contract_registry import ContractRegistry

registry = ContractRegistry(catalog="main", schema="data_governance")
registry.initialize()
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This creates the contract_registry Delta table with change data feed enabled.

Step 3: Choose Your Starting Point

Pick 3-5 critical datasets to contract first. Prioritize:

  • Datasets with the most downstream consumers
  • Datasets with known quality issues
  • Datasets required for regulatory reporting
  • Revenue-impacting datasets

Phase 2: Contract Authoring (Days 4-7)

Step 4: Generate Contracts from Existing Tables

Use the CLI generator to bootstrap contracts from live tables:

python cli/contract_generator.py \
  --catalog main \
  --schema production \
  --table customer_events \
  --output ./contracts/ \
  --domain analytics \
  --team data-engineering \
  --contact data-eng@company.com
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To generate contracts for all tables in a schema:

python cli/contract_generator.py \
  --catalog main \
  --schema production \
  --all \
  --output ./contracts/
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Step 5: Customize Generated Contracts

Each generated contract is a starting point. Review and customize:

  1. Status: Change from draft to active once reviewed.
  2. SLA thresholds: Set realistic freshness, completeness, and accuracy targets.
  3. Constraints: Add field-level validation rules (patterns, allowed values, ranges).
  4. Quality rules: Define custom SQL expressions for business logic validation.
  5. PII flags: Mark fields containing personally identifiable information.
  6. Lineage: Add upstream sources and downstream consumers.

Refer to spec/contract_schema.yaml for the full specification of available fields.

Step 6: Use Templates for New Sources

For new data sources, start from one of the provided templates:

Source Type Template
REST API / Webhook templates/contract_templates/api_source.yaml
Database CDC / Batch templates/contract_templates/database_source.yaml
File (CSV, JSON, etc.) templates/contract_templates/file_source.yaml

Copy the template, replace all <placeholder> values, and add domain-specific fields.

Step 7: Register Contracts 

registry.register("./contracts/customer_events.yaml", registered_by="data-eng-lead")
registry.activate("customer_events", "1.0.0")
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Phase 3: Validation & Monitoring (Days 8-14)

Step 8: Validate Data Against Contracts

Run the validator against live tables:

python cli/contract_validator.py \
  --contract ./contracts/customer_events.yaml \
  --source main.production.customer_events
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For CI/CD integration, use --strict to fail on warnings:

python cli/contract_validator.py \
  --contract ./contracts/customer_events.yaml \
  --source main.production.customer_events \
  --strict \
  --output ./reports/customer_events_validation.txt
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Step 9: Deploy SLA Monitoring

  1. Upload notebooks/sla_monitoring.py to your Databricks workspace.
  2. Upload all active contract YAML files to a Volumes path: 
/Volumes/main/contracts/active/
  customer_events.yaml
  financial_transactions.yaml
  product_catalog.yaml
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  1. Create a scheduled Databricks job:
    • Task: sla_monitoring.py
    • Schedule: Every 15 minutes (adjust to your needs)
    • Parameters:
      • contract_path: /Volumes/main/contracts/active
      • catalog: main
      • schema: data_governance
      • alert_on_breach: true (for production)

Step 10: Configure Alerting

Set up notifications on the SLA monitoring job:

  • Email alerts on job failure (which triggers on SLA breach)
  • Slack integration via webhook for real-time notification
  • PagerDuty for P1 freshness breaches on critical datasets

Phase 4: CI/CD Integration (Days 15-21)

Step 11: Add Breaking Change Detection

Integrate the breaking change detector into your pull request workflow:

  1. Store contracts in your Git repository under contracts/.
  2. Add a CI step that compares the proposed contract against the current baseline: 
# .github/workflows/contract-check.yml (GitHub Actions example)
name: Contract Change Check
on:
  pull_request:
    paths:
      - 'contracts/**'

jobs:
  check-breaking-changes:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0
      - name: Get changed contracts
        id: changes
        run: |
          echo "files=$(git diff --name-only origin/main -- contracts/)" >> $GITHUB_OUTPUT
      - name: Run breaking change detector
        if: steps.changes.outputs.files != ''
        run: |
          # For each changed contract, compare against main branch version
          for file in ${{ steps.changes.outputs.files }}; do
            git show origin/main:$file > /tmp/baseline.yaml 2>/dev/null || continue
            python notebooks/breaking_change_detector.py \
              --baseline /tmp/baseline.yaml \
              --proposed $file \
              --fail-on-breaking
          done
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Step 12: Automate Contract Registration

Add a post-merge step to automatically register updated contracts:

# In your CI/CD pipeline after merge to main:
from contract_registry import ContractRegistry

registry = ContractRegistry(catalog="main", schema="data_governance")
for contract_file in changed_files:
    registry.register(contract_file, registered_by="ci-pipeline")
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Phase 5: Dashboards & Governance (Days 22-30)

Step 13: Deploy the Compliance Dashboard

  1. Upload notebooks/contract_compliance_dashboard.py to your workspace.

  2. Create a scheduled job running daily:

    • Parameters:
      • catalog: main
      • schema: data_governance
      • lookback_days: 30

  3. Connect your BI tool (Databricks SQL, Power BI, Tableau) to the dashboard tables:

    • dashboard_overall_compliance
    • dashboard_compliance_by_contract
    • dashboard_compliance_by_check_type
    • dashboard_daily_compliance_trend
    • dashboard_breach_summary
    • dashboard_freshness_distribution

Step 14: Establish Producer-Consumer Agreements

For each critical data contract, formalize the relationship:

  1. Copy templates/producer_consumer_agreement.md.
  2. Fill in all sections with both producer and consumer teams.
  3. Review and sign off.
  4. Store alongside the contract YAML in version control.

Step 15: Roll Out to Additional Datasets

Expand coverage incrementally:

  • Generate contracts for all tables in each schema
  • Prioritize based on consumer count and business criticality
  • Set a target: 100% coverage for production schemas within 90 days

Versioning Strategy

Follow semantic versioning for all contracts:

Change Type Version Bump Example
Breaking schema change Major 1.2.0 -> 2.0.0
New optional field, relaxed constraint Minor 1.2.0 -> 1.3.0
Documentation, description update Patch 1.2.0 -> 1.2.1

Recommended Folder Structure 

your-repo/
  contracts/
    active/
      customer_events.yaml
      financial_transactions.yaml
      product_catalog.yaml
    deprecated/
      legacy_events_v1.yaml
    drafts/
      new_feature_events.yaml
  agreements/
    customer_events_agreement.md
  .github/
    workflows/
      contract-check.yml
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Troubleshooting

Contract generator fails with "No active SparkSession"

Run the generator inside a Databricks notebook or ensure your local environment
has PySpark configured. Alternatively, export table metadata as JSON and use
the --from-json flag.

SLA monitoring reports no contracts found

Verify that the contract_path widget points to a valid Volumes or DBFS path
containing .yaml files. Check file permissions in Unity Catalog.

Breaking change detector shows false positives

Ensure you are comparing the correct baseline version. The detector compares
the exact files provided — it does not resolve versions from the registry
automatically. Use git show origin/main:<path> to get the current production
baseline.

Registry table not found

Run registry.initialize() to create the table. This is idempotent and safe
to run multiple times.

Support

For questions about this framework, visit datanest.dev.

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