The MemcachedProxy custom resource is used to define the configuration used to create a mcrouter memcached proxy instance. This document is a reference for the format of the MemcachedProxy resource.

The overall format of the proxy object consists of generic Kubernetes fields like the API version, kind, and metadata, as well as the specification for the proxy.

apiVersion: ianlewis.org/v1alpha1
kind: MemcachedProxy
metadata:
  name: sharded-example
spec:
  rules:
    type: "sharded"
    service:
      name: "sharded-memcached"
      port: 11211

The Memcached Proxy Specification

The MemcachedProxySpec defines the specification for the proxy. It is made up of mcrouter specific configuration the and a root routing rule.

Here is the definition for the proxy specification in Go:

type MemcachedProxySpec struct {
	Rules    RuleSpec     `json:"rules"`
	McRouter McRouterSpec `json:"mcrouter"`
}

Routing Rules

Routing rules form an arbitrary tree where the root nodes are rules that reference Kubernetes services. Each routing rule has a type and can either have a service or children.

• type can be either "sharded" or "replicated". The default is "sharded".
  • "sharded" indicates that requests are sharded among member pods in the referenced service, or among each child routing rule. See the sharded pools documentation for more details.
  • "replicated" indicates that write requests are replicated to each member pod in the referenced service, or to each child routing rule. Get requests are routed to a random pod or child route based on host ID of the mcrouter instance. See the replicated pools documentation for more details.
• service indicates that requests to this route should be routed to member pods of the service.
• children indicates that requests to this route should be routed tothe given child routes.

Here is the definition for the routing rule in Go:

type RuleSpec struct {
	Type     string       `json:"type"`
	Service  *ServiceSpec `json:"service,omitempty"`
	Children []RuleSpec   `json:"children,omitempty"`
}