https://github.com/mozamimy/mimikyu

Tiny proxy of ElastiCahce Memceched configuration endpoint
https://github.com/mozamimy/mimikyu

aws elasticache memcached-server

Last synced: 14 days ago
JSON representation

Tiny proxy of ElastiCahce Memceched configuration endpoint

• Host: GitHub
• URL: https://github.com/mozamimy/mimikyu
• Owner: mozamimy
• License: mit
• Created: 2019-06-05T04:15:09.000Z (almost 7 years ago)
• Default Branch: master
• Last Pushed: 2019-06-06T03:49:19.000Z (almost 7 years ago)
• Last Synced: 2024-10-18T23:14:36.971Z (over 1 year ago)
• Topics: aws, elasticache, memcached-server
• Language: Rust
• Size: 65.4 KB
• Stars: 3
• Watchers: 1
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE.txt

Awesome Lists containing this project

README

          
# Mimikyu

[![CircleCI](https://circleci.com/gh/mozamimy/mimikyu.svg?style=svg)](https://circleci.com/gh/mozamimy/mimikyu)

Mimikyu is a tiny proxy of ElastiCahce Memceched configuration endpoint designed for safe migration between 2 Memcached clusters.

This implementation is very rough. Please test carefully with your Memcached client before use in production.

## How Mimikyu works

Amazon ElasiCahce Memcached has a mechanism for auto-discovery nodes consists of a Memcached cluster. The configuration endpoint provides the feature.

A Memcached client implemented the auto-discovery protocol fetches all node information (endpoint, port, and so on.) from the endpoint by use `config get cluster` command.

- https://docs.aws.amazon.com/AmazonElastiCache/latest/mem-ug/AutoDiscovery.html

- https://docs.aws.amazon.com/AmazonElastiCache/latest/mem-ug/AutoDiscovery.HowAutoDiscoveryWorks.html

Mimikyu emulates the configuration endpoint. When Mimikyu receives a request from client,

- If the sent command is `stats`

    - Execute same `stats` command to upstream primary cluster. Then, send the response to the client as it as.

    - Respond with secondary stats when primary endpoint is down.

- If the sent command is `config get cluster`

    - Execute `config get cluster` for upstream primary/secondary clusters and collect the responses.

    - Then, put the endpoint information together as a single response for the client.

- If other commands is sent, Mimikyu just returns `SERVER_ERROR` and close the connection from client.

- Also Mimikyu returns error when primary and secondary upstream is down or not exist.

![](docs/how_it_works.png)

As a result, the client of Mimikyu can discover all nodes included primary cluster and secondary cluster. Hence, we can decrease nodes of primary cluster gradually. 

## Usage

See `mimikyu --help`.

## License

MIT