goriak

goriak

Current version: v1.0.0.
Riak KV version: 2.0 or higher, the latest version of Riak KV is always recommended.

What is goriak?

goriak is a wrapper around riak-go-client to make it easier and more friendly for developers to use Riak KV.

Installation

go get -u gopkg.in/zegl/goriak.v1

Maps

The main feature of goriak is that goriak automatically can marshal/unmarshal your Go types into Riak data types.

SetMap

In the example below Name will be saved as a register, and Aliases will be a set.

type User struct {
    Name    string
    Aliases []string
}

user := User {
    Name:   "Foo",
    Alises: []string{"Foo", "Bar"},
}

goriak.SetMap("bucket-name", "bucket-type", "key", user)

GetMap

The map can later be retreived as a whole:

var res User
goriak.GetMap("bucket-name", "bucket-type", "key", &res)

MapOperation

There is a time in everyones life where you need to perform raw MapOperations.

Some operations, such as RemoveFromSet requires a Context to perform the operation. A Context can be retreived from GetMap by setting a special context type.

type ourType struct {
    Aliases []string

    // The context from Riak will be added if the tag goriakcontext is provided
    Context []byte `goriak:"goriakcontext"`
}

// ... GetMap()

// Works with MapOperation from github.com/basho/riak-go-client
operation := goriak.NewMapOperation()
operation.AddToSet("Aliases", []byte("Baz"))

goriak.MapOperation("bucket-name", "bucket-type", "key", operation, val.Context)

Supported Go types

Golang map types

Supported key types: int, int8, int16, int32, int64, string.
Supported value types: string, []byte.

Helper types

Some actions are more complicated then neccesary with the use of the default Go types and MapOperations.

This is why goriak contains the types goriak.Counter and goriak.Set. Both of these types will help you performing actions such as incrementing a value, or adding/removing items.

Counters

Riak Counters is supported with the special goriak.Counter type.

Example:

type Article struct {
    Title string
    Views *goriak.Counter
}

// Get our object
var article Article
con.GetMap("articles", "map", "1-hello-world", &article)

// Increase views by 1
err := article.Views.Increase(1).Exec(con)

// check err

Counter.Exec(con) will make a lightweight request to Riak, and the counter is the only object that will be updated.

You can also save the changes to your counter with SetMap(), this is useful if you want to change multiple counters at the same time.

Check godoc for more information.

Sets

You can chose to use goriak.Set to help you with Set related actions, such as adding and removing items. goriak.Set also has support for sending incremental actions to Riak so that you don't have to build that functionality yourself.

Example:

type Article struct {
    Title string
    Tags *goriak.Set
}

// Get our object
var article Article
con.GetMap("articles", "map", "1-hello-world", &article)

// Add the tag "animals"
err := article.Tags.AddString("animals").Exec(con)

// check err

Check godoc for more information.

Values

Values are automatically JSON encoded and decoded.

SetValue

goriak.SetValue("bucket-name", "bucket-type", "key", obj)

GetValue

goriak.GetValue("bucket-name", "bucket-type", "key", &obj)

Secondary Indexes

You can set secondary indexes on Values with SetValue by using struct tags.

type User struct {
    Name    string `goriakindex:"nameindex_bin"`
    Aliases []string
}

When saved the next time the index will be updated.

Keys in a particular index can be retreived with KeysInIndex.

goriak.KeysInIndex("bucket-name", "bucket-type", "nameindex_bin", "Value")

Indexes can also be used in slices. If you are using a slice every value in the slice will be added to the index.

type User struct {
    Aliases []string `goriakindex:"aliasesindex_bin"`
}