database-migrations-migration-observability

What this skill does

# Migration Observability and Real-time Monitoring

You are a database observability expert specializing in Change Data Capture, real-time migration monitoring, and enterprise-grade observability infrastructure. Create comprehensive monitoring solutions for database migrations with CDC pipelines, anomaly detection, and automated alerting.

## Use this skill when

- Working on migration observability and real-time monitoring tasks or workflows
- Needing guidance, best practices, or checklists for migration observability and real-time monitoring

## Do not use this skill when

- The task is unrelated to migration observability and real-time monitoring
- You need a different domain or tool outside this scope

## Context
The user needs observability infrastructure for database migrations, including real-time data synchronization via CDC, comprehensive metrics collection, alerting systems, and visual dashboards.

## Requirements
$ARGUMENTS

## Instructions

### 1. Observable MongoDB Migrations

```javascript
const { MongoClient } = require('mongodb');
const { createLogger, transports } = require('winston');
const prometheus = require('prom-client');

class ObservableAtlasMigration {
    constructor(connectionString) {
        this.client = new MongoClient(connectionString);
        this.logger = createLogger({
            transports: [
                new transports.File({ filename: 'migrations.log' }),
                new transports.Console()
            ]
        });
        this.metrics = this.setupMetrics();
    }

    setupMetrics() {
        const register = new prometheus.Registry();

        return {
            migrationDuration: new prometheus.Histogram({
                name: 'mongodb_migration_duration_seconds',
                help: 'Duration of MongoDB migrations',
                labelNames: ['version', 'status'],
                buckets: [1, 5, 15, 30, 60, 300],
                registers: [register]
            }),
            documentsProcessed: new prometheus.Counter({
                name: 'mongodb_migration_documents_total',
                help: 'Total documents processed',
                labelNames: ['version', 'collection'],
                registers: [register]
            }),
            migrationErrors: new prometheus.Counter({
                name: 'mongodb_migration_errors_total',
                help: 'Total migration errors',
                labelNames: ['version', 'error_type'],
                registers: [register]
            }),
            register
        };
    }

    async migrate() {
        await this.client.connect();
        const db = this.client.db();

        for (const [version, migration] of this.migrations) {
            await this.executeMigrationWithObservability(db, version, migration);
        }
    }

    async executeMigrationWithObservability(db, version, migration) {
        const timer = this.metrics.migrationDuration.startTimer({ version });
        const session = this.client.startSession();

        try {
            this.logger.info(`Starting migration ${version}`);

            await session.withTransaction(async () => {
                await migration.up(db, session, (collection, count) => {
                    this.metrics.documentsProcessed.inc({
                        version,
                        collection
                    }, count);
                });
            });

            timer({ status: 'success' });
            this.logger.info(`Migration ${version} completed`);

        } catch (error) {
            this.metrics.migrationErrors.inc({
                version,
                error_type: error.name
            });
            timer({ status: 'failed' });
            throw error;
        } finally {
            await session.endSession();
        }
    }
}
```

### 2. Change Data Capture with Debezium

```python
import asyncio
import json
from kafka import KafkaConsumer, KafkaProducer
from prometheus_client import Counter, Histogram, Gauge
from datetime import datetime

class CDCObservabilityManager:
    def __init__(self, config):
        self.config = config
        self.metrics = self.setup_metrics()

    def setup_metrics(self):
        return {
            'events_processed': Counter(
                'cdc_events_processed_total',
                'Total CDC events processed',
                ['source', 'table', 'operation']
            ),
            'consumer_lag': Gauge(
                'cdc_consumer_lag_messages',
                'Consumer lag in messages',
                ['topic', 'partition']
            ),
            'replication_lag': Gauge(
                'cdc_replication_lag_seconds',
                'Replication lag',
                ['source_table', 'target_table']
            )
        }

    async def setup_cdc_pipeline(self):
        self.consumer = KafkaConsumer(
            'database.changes',
            bootstrap_servers=self.config['kafka_brokers'],
            group_id='migration-consumer',
            value_deserializer=lambda m: json.loads(m.decode('utf-8'))
        )

        self.producer = KafkaProducer(
            bootstrap_servers=self.config['kafka_brokers'],
            value_serializer=lambda v: json.dumps(v).encode('utf-8')
        )

    async def process_cdc_events(self):
        for message in self.consumer:
            event = self.parse_cdc_event(message.value)

            self.metrics['events_processed'].labels(
                source=event.source_db,
                table=event.table,
                operation=event.operation
            ).inc()

            await self.apply_to_target(
                event.table,
                event.operation,
                event.data,
                event.timestamp
            )

    async def setup_debezium_connector(self, source_config):
        connector_config = {
            "name": f"migration-connector-{source_config['name']}",
            "config": {
                "connector.class": "io.debezium.connector.postgresql.PostgresConnector",
                "database.hostname": source_config['host'],
                "database.port": source_config['port'],
                "database.dbname": source_config['database'],
                "plugin.name": "pgoutput",
                "heartbeat.interval.ms": "10000"
            }
        }

        response = requests.post(
            f"{self.config['kafka_connect_url']}/connectors",
            json=connector_config
        )
```

### 3. Enterprise Monitoring and Alerting

```python
from prometheus_client import Counter, Gauge, Histogram, Summary
import numpy as np

class EnterpriseMigrationMonitor:
    def __init__(self, config):
        self.config = config
        self.registry = prometheus.CollectorRegistry()
        self.metrics = self.setup_metrics()
        self.alerting = AlertingSystem(config.get('alerts', {}))

    def setup_metrics(self):
        return {
            'migration_duration': Histogram(
                'migration_duration_seconds',
                'Migration duration',
                ['migration_id'],
                buckets=[60, 300, 600, 1800, 3600],
                registry=self.registry
            ),
            'rows_migrated': Counter(
                'migration_rows_total',
                'Total rows migrated',
                ['migration_id', 'table_name'],
                registry=self.registry
            ),
            'data_lag': Gauge(
                'migration_data_lag_seconds',
                'Data lag',
                ['migration_id'],
                registry=self.registry
            )
        }

    async def track_migration_progress(self, migration_id):
        while migration.status == 'running':
            stats = await self.calculate_progress_stats(migration)

            self.metrics['rows_migrated'].labels(
                migration_id=migration_id,
                table_name=migration.table
            ).inc(stats.rows_processed)

            anomalies = await self.detect_anomali