What is a projection in event sourcing?

A projection is a process that transforms a stream of events into a specific read model or state representation optimized for querying, rather than keeping data in its original transactional format.

Does this skill support Elasticsearch?

Yes, the skill includes specific templates and logic patterns for projecting event data into Elasticsearch to enable advanced full-text search capabilities.

When should I use the Persistent projection type?

Use Persistent projections when you need to store checkpoints, allowing the projector to resume processing from the exact event it last handled after a service restart or failure.

How does this skill facilitate CQRS implementation?

It provides the structural logic for the 'Read' side of CQRS, ensuring that your query-optimized databases stay synchronized with the 'Write' side (the event store) asynchronously.

Event Sourcing Projection Patterns

Name: Event Sourcing Projection Patterns
Author: gwickman

bygwickman

0•

Database Management

Builds high-performance read models and materialized views from event streams using CQRS and projection patterns.

This skill provides a comprehensive framework for implementing projection patterns within event-sourced architectures, helping developers build efficient read models for CQRS systems. It offers architectural guidance and code templates for various projection types, including live subscriptions, historical catchups, and persistent checkpointing. By using this skill, you can decouple your write and read models to optimize query performance, implement real-time dashboards, and synchronize data across different storage engines like SQL databases and Elasticsearch indexes.

Key Features

01Standardized projection architecture for CQRS read sides

02Support for Live, Catchup, Persistent, and Inline projection types

030 GitHub stars

04Patterns for complex data aggregation and real-time reporting

05Automated checkpoint management for reliable event resumption

06Pre-built templates for SQL summaries and Elasticsearch indexing

Use Cases

01Synchronizing primary event data with search engines like Elasticsearch

02Optimizing query performance in high-scale event-sourced systems

03Building real-time analytics dashboards from transactional event streams

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add gwickman/auto-dev-test-target-1 projection-patterns

For use in Claude.ai and ChatGPT

Download Skill