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Memcached Cloud is a fully-managed service for running your Memcached in a reliable and fail-safe manner. Your dataset is constantly replicated, so if a node fails, an auto-switchover mechanism guarantees data is served without interruption. Memcached Cloud provides various data persistence options as well as remote backups for disaster recovery purposes. You can quickly and easily get your apps up and running with Memcached Cloud through its add-on for Codename: BlueMix, just tell us how much memory you need and get started instantly with your first Memcached bucket.

A Memcached bucket is created in seconds and from that moment on, all operations are fully-automated. The service completely frees developers from dealing with nodes, clusters, server lists, scaling and failure recovery, while guaranteeing absolutely no data loss.

Creating A Memcached Cloud Service

You can use the Codename: BlueMix web user interface or the cf command line interface to create an instance of the Memcached Cloud service. The following cf command creates the service instance:

$ cf create-service memcachedcloud PLAN SERVICE_INSTANCE

where PLAN is the desired plan (e.g. the free 25mb plan) and SERVICE_INSTANCEis the name of the service instance.

Binding Your Memcached Cloud Service

Use the web user interface or the command line interface to bind a Memcached Cloud service instance to an application. When using cf, the following command binds the instance to the application:

$ cf bind-service APP SERVICE_INSTANCE

where APP is the name of the application and SERVICE_INSTANCE is the name of the service instance.

Once your Memcached Cloud service is bound to your app, the service credentials will be stored in the VCAP_SERVICES environment variable in the following format:

{
   "memcachedcloud-null": [
      {
         "name": "dev-session-cache",
         "label": "memcachedcloud-null",
         "plan": "25mb",
         "credentials": {
            "username": "...",
            "servers": "pub-memcached-11211.dal-05.1.sl.redislabs.com:11211",
            "password": "..."
         }
      }
   ]
}

Using Memcached with Ruby

Dalli is a high performance pure Ruby client for accessing memcached servers, which uses the binary protocol.

For usage with Rails 3.x, update the Gemfile:

gem 'dalli'

And then install the gem via Bundler:

bundle install

Parse your credentials as follows:

memcachedcloud_service = JSON.parse(ENV['VCAP_SERVICES'])["memcachedcloud-n/a"]
credentials = memcachedcloud_service.first["credentials"]

Lastly, in your config/environments/production.rb:

	config.cache_store = :dalli_store, credentials.servers, { :username => credentials.username, :password => credentials.password }

Configuring Memcached on Sinatra

Add this code snippet to your configure block:

configure do
    . . .
	require 'dalli'
	memcachedcloud_service = JSON.parse(ENV['VCAP_SERVICES'])["memcachedcloud-n/a"]
	credentials = memcachedcloud_service.first["credentials"]
    	$cache = Dalli::Client.new(credentials.servers.split(','), :username => credentials.username, :password => credentials.password)
    . . .
end

Testing from Ruby

$cache.set("foo", "bar")
# => true
$cache.get("foo")
# => "bar"

Using Memcached with Java

spymemcached is a simple, asynchronous, single-threaded memcached client written in Java. You can download the latest build from: https://code.google.com/p/spymemcached/downloads/list.

To use the maven repository, start by specifying the repository:

<repositories>
    <repository>
      <id>spy</id>
      <name>Spy Repository</name>
      <layout>default</layout>
      <url>http://files.couchbase.com/maven2/</url>
      <snapshots>
        <enabled>false</enabled>
      </snapshots>
    </repository>
</repositories>

And specify the actual artifact as follows:

<dependency>
  <groupId>spy</groupId>
  <artifactId>spymemcached</artifactId>
  <version>2.8.9</version>
  <scope>provided</scope>
</dependency>

Configure the connection to your Memcached Cloud service using the VCAP_SERVICES environment variable and the following code snippet:

try {
	String vcap_services = System.getenv("VCAP_SERVICES");
	if (vcap_services != null && vcap_services.length() > 0) {
		// parsing memcachedcloud credentials
		JsonRootNode root = new JdomParser().parse(vcap_services);
		JsonNode "memcachedcloudNode = root.getNode("memcachedcloud-n/a");
		JsonNode credentials = "memcachedcloudNode.getNode(0).getNode("credentials");
		
		// building the memcached client
		AuthDescriptor ad = new AuthDescriptor(new String[] { "PLAIN" },
		        new PlainCallbackHandler(credentials.getStringValue("username"), credentials.getStringValue("password")));
			
		MemcachedClient mc = new MemcachedClient(
		          new ConnectionFactoryBuilder()
		              .setProtocol(ConnectionFactoryBuilder.Protocol.BINARY)
		              .setAuthDescriptor(ad).build(),
		          AddrUtil.getAddresses(credentials.getStringValue("servers")));
		
	}			
} catch (InvalidSyntaxException ex) {
	// vcap_services could not be parsed.
} catch (IOException ex) {
	// the memcached client could not be initialized. 
}

Testing from Java

mc.set("foo", 0, "bar");
Object value = mc.get("foo");

Dashboard

Our dashboard presents all performance and usage metrics of your Memcached Cloud service on a single screen, as shown below:

Dashboard

To access your Memcached Cloud dashboard, click the service instance in your Code Name: BlueMix console and then the LAUNCH MEMCACHEDCLOUD DASHBOARD button.

When using the Memcached Cloud console, you can then find the dashboard using the MY RESOURCES->Dashboard menu item.

Support

Any Memcached Cloud support issues or product feedbacks are welcome via email at support@redislabs.com or from the service's console under the SUPPORT->Helpdesk menu item.

Additional resources