Consistent Hashing

The purpose of this program is to demonstrate how consistent hashing works and to implement a simple RESTful key-value cache data store

Server Side Cache Data Store

A simple RESTful key-value data store with the following features:

1. PUT http://localhost:3000/keys/{key_id}/{value}

- Request:

  ```http
  PUT http://localhost:3000/keys/1/foobar
  ```
- Response: 

  ```http
  HTTP 200
  ```

2. GET http://localhost:3000/keys/{key_id}

- Request:

  ```http
  GET  http://localhost:3000/keys/1/foobar
  ```

- Response:
  ```json
  {
  "key" : 1,
  "value" : "foobar"
  }
  ```

3. GET http://localhost:3000/keys

- Request:

  ```http
  GET  http://localhost:3000/keys
  ```
- Response:
  ```json
    [
      {
        "key" : 1,
        "value" : "foobar"
      },
      {
        "key" : 2,
        "value" : "b"
      }
    ]
    ```

Three server instances using ports 3000, 3001, and 3002

server1.go: http://localhost:3000

server2.go: http://localhost:3001

server3.go: http://localhost:3002

---

Consistent Hashing on Client Side

A consistent hashing client in GO to support PUT and GET [/keys/{key_id}] operations.

Hashing algorithm - crc32

https://golang.org/pkg/hash/crc32/

client.go