Introduction to Riak, and Riak-CS at "Munich Rubyshift The big Ruby & Database shootout!" 9/2013 http://www.meetup.com/Munich-Rubyshift-Ruby-User-Group/

1. PUT Knowledge BUCKET
Brain KEY Riak
An intro to Riak
by Phil
github.com/sideshowcoder
twitter.com/ischi

2. Code
The slides contain code, this is how it works
a_string = "I am a string"
a_string

3. Ok so Riak, eh?
client = Riak::Client.new
bucket = client.bucket("brain")
object = bucket.get_or_new("riak")
object.content_type = "application/json"
object.data = { message: "Know stuff on riak!", level: "awesome" }
object.store
object.reload.data

4. What is Riak?
Key / Value Store
Distributed
Dynamo based

5. Buckets
client.bucket("brain").name

6. Keys
bucket.keys

7. Values
bucket.get("riak").data

8. Distributed
Keyspace is spread across the members of a cluster via Consistent
Hashing

9. Hashing
Key => Hash(key) => Result => 2ˆn -1 possible outcomes
Digest.hexencode Digest::MD5.digest("my-key")

10. Consistent Hashing
Source littleriakbook

11. Replication
Source littleriakbook

12. CAP Theorem
Consistency
Availability
Partition tolerance

13. Trade-offs
Riak chooses adjustable AP, which means it never reaches full
Consistency but can be tuned to the needs

14. N/R/W Values
N: Replication count
R: Min number of nodes to read from
W: Min number of nodes to write to

15. More on the basics behind
this?
Littleriakbook by Eric Redmond
dynamo paper

16. Ring members
$ riak-admin member-status
=========================== Membership ============================
Status Ring Pending Node
-------------------------------------------------------------------
valid 100.0% -- 'riak@127.0.0.1'
-------------------------------------------------------------------
Valid:1 / Leaving:0 / Exiting:0 / Joining:0 / Down:0

17. Ring Status
$ riak-admin ring-status
============================ Claimant =============================
Claimant: 'riak@127.0.0.1'
Status: up
Ring Ready: true
======================== Ownership Handoff ========================
No pending changes.
======================== Unreachable Nodes ========================
All nodes are up and reachable

18. Just Key / Value store? ...
mehh!
Tags
Map and Reduce
S3...

19. 2i aka Secondary Indexes
aka Tags
object = bucket.get("riak")
object.indexes["level_bin"] = ["awesome"]
object.store
bucket.get_index("level_bin", "awesome")

20. Map and Reduce
js_func = "function(v){ return [Riak.mapValuesJson(v)[0].message]; }"
Riak::MapReduce.new(client)
.add("brain", "riak")
.map(js_func, :keep => true)
.run

21. Let's talk S3
Wait what?

22. Run your own S3 (compatible) backed by Riak

23. Features
Same API as S3 (use aws-sdk in ruby)
Great reporting facilities
It's your own S3!

24. Setup
Install Riak
Install RiakCS
Install Stanchion
It's detailed here

25. ... or just setup via Vagrant!
$ vagrant plugin install vagrant-berkshelf
$ vagrant plugin install vagrant-omnibus
$ git clone https://github.com/basho/vagrant-riak-cs-cluster
$ cd vagrant-riak-cs-cluster
$ RIAK_CS_CREATE_ADMIN_USER=1 vagrant up
Virtual setup using vagrant

26. Create a user
curl -H 'Content-Type: application/json' -X POST
http://127.0.0.1:8080/riak-cs/user
--data '{"email":"admin@admin.com", "name":"admin"}'

27. OK let's try it!
AWS::S3.new({
:access_key_id => "8AA5UQR3EACDS_TIAXLV",
:secret_access_key => "M5eG0q1pN9y6hlc4-JbiCHXLt1YXCY2n7Sb5Yg==",
:use_ssl => false,
:proxy_uri => "http://localhost:8080"
})

28. Create a bucket
s3bucket = s3.buckets.create("my-bucket", :acl => :public_read)
s3.buckets.map(&:name)

29. Write something!
obj = s3bucket.objects["riak.jpg"]
obj.write File.read('./images/riak.jpg')
obj.acl = :public_read
s3bucket.objects.map(&:key)

30. OK lets read it back
This is loaded from local Riak CS

31. Recap
Distributes Key / Value Store
Easy to interface with
Clients are build of HTTP
Use RiakCS to replace or augment S3

32. Questions?

33. Resources
Littleriakbook by Eric Redmond
Basho docs on Racks