TL;DR

Spyglass is a very fast Clojure client for Memcached (as well as Couchbase and Kestrel) built on top of SpyMemcached.

1.1.0 is a minor release that introduces several minor features andhas breaking changes.

Changes between 1.0.0 and 1.1.0

Clojure 1.4 Requirement

Spyglass 1.1.0 drops support for Clojure 1.3.

Heroku Add-on Support

By using SpyMemcached 2.8.9, you now can use Spyglass with Heroku Memcached add-ons:

1
2
3
4
5
6

(defproject my-great-project "0.1.0-SNAPSHOT"
  :dependencies [[org.clojure/clojure "1.5.1"]
                 [clojurewerkz/spyglass "1.1.0-beta6-SNAPSHOT"
                  :exclusions [spy/spymemcached]]
                 [spy/spymemcached "2.8.9"]]
  :repositories {"spy-memcached" {:url "http://files.couchbase.com/maven2/"}})

Contributed by Connor Mendenhall.

Clojure 1.5 By Default

Spyglass now depends on org.clojure/clojure version 1.5.1. It is still compatible with Clojure 1.3+ and if your project.clj depends on a different version, it will be used, but 1.5 is the default now.

We encourage all users to upgrade to 1.5, it is a drop-in replacement for the majority of projects out there.

Asynchronous Cache Store

Spyglass now ships both sync and async implementations of clojure.core.cache.

To instantiate async store, use clojurewerkz.spyglass.cache/async-spyglass-cache-factory. clojurewerkz.spyglass.cache/spyglass-cache-factory was renamed to clojurewerkz.spyglass.cache/sync-spyglass-cache-factory.

Contributed by Joseph Wilk.

Fix Authentication Support

clojurewerkz.spyglass.client/text-connection and clojurewerkz.spyglass.client/bin-connection no longer fail when credentials are passed in.

Empty gets Responses

clojurewerkz.spyglass.client/gets now correctly handles responses for keys that do not exist.

GH issue: #4.

SASL (Authentication) Support

clojurewerkz.spyglass.client/text-connection and clojurewerkz.spyglass.client/bin-connection now support credentials:

(ns my.service (:require [clojurewerkz.spyglass.client :as c]))

;; uses credentials from environment variables, e.g. on Heroku: (c/text-connection “127.0.0.1:11211” (System/getenv “MEMCACHE_USERNAME”)

                                 (System/getenv "MEMCACHE_PASSWORD"))

When you need to fine tune things and want to use a custom connection factory, you need to instantiate auth descriptor and pass it explicitly, like so:

1
2
3
4
5
6
7
8

(ns my.service
  (:require [clojurewerkz.spyglass.client :as c])
  (:import [net.spy.memcached.auth AuthDescriptor]))

(let [ad (AuthDescriptor/typical (System/getenv "MEMCACHE_USERNAME")
                                 (System/getenv "MEMCACHE_PASSWORD"))]
  (c/text-connection "127.0.0.1:11211" (c/text-connection-factory :failure-mode :redistribute
                                                                  :aut-descriptor ad)))

Blocking Deref for Futures

Futures returned by async Spyglass operations now implement “blocking dereferencing”: they can be dereferenced with a timeout and default value, just like futures created with clojure.core/future and similar.

Contributed by Joseph Wilk.

Support For Configurable Connections

New functions clojurewerkz.spyglass.client/text-connection-factory and clojurewerkz.spyglass.client/bin-connection-factory provide a Clojuric way of instantiating connection factories. Those factories, in turn, can be passed to new arities of clojurewerkz.spyglass.client/text-connection and clojurewerkz.spyglass.client/bin-connection to control failure mode, default transcoder and so on:

1
2
3
4

(ns my.service
  (:require [clojurewerkz.spyglass.client :as c]))

(c/text-connection "127.0.0.1:11211" (c/text-connection-factory :failure-mode :redistribute))

core.cache Implementation

clojurewerkz.spyglass.cache now provides a clojure.core.cache implementation on top of Memcached:

1
2
3
4
5
6
7
8
9

(ns my.service
  (:require [clojurewerkz.spyglass.client :as sg]
            [clojurewerkz.spyglass.cache  :as sc]
            [clojure.core.cache           :as cc]))

(let [client (sg/text-connection)
      cache  (sc/sync-spyglass-cache-factory)]
      (cc/has? cache "a-key")
      (cc/lookup cache "a-key"))

SyncSpyglassCache uses synchronous operations from clojurewerkz.spyglass.client. Asynchronous implementation that returns futures will be added in the future.

SpyMemcached 2.8.10

SpyMemcached has been upgraded to 2.8.10.

Improved Couchbase Support

clojurewerkz.spyglass.couchbase/connection is a new function that connects to Couchbase with the given bucket and credentials. It returns a client that regular clojurewerkz.spyglass.memcached functions can use.

Change Log

We recommend all users to give 1.1.0 a try.

Spyglass change log is available on GitHub.

Spyglass is a ClojureWerkz Project

Spyglass is part of the group of libraries known as ClojureWerkz, together with

• Langohr, a Clojure client for RabbitMQ that embraces the AMQP 0.9.1 model
• Elastisch, a minimalistic Clojure client for ElasticSearch
• Monger, a Clojure MongoDB client for a more civilized age
• Neocons, a feature rich idiomatic Clojure client for the Neo4J REST API * Welle, a Riak client with batteries included
• Quartzite, a powerful scheduling library

and several others. If you like Spyglass, you may also like our other projects.

Let us know what you think on Twitter or on the Clojure mailing list.

Michael on behalf of the ClojureWerkz Team