I would like to introduce you to my Go Cassandra client/library, Gossie:


My intention was to use my favorite database with my favorite language, with a library that allowed me to take advantage of idiomatic Go code with the main strengths of Cassandra. I focused on offering a smooth as possible integration with Go, including auto marshaling of most primitive built-in types and structs. I also wanted to focus on what I think is the main strength of the Cassandra data model, its column-oriented storage with ordering, which I think it is unfortunately overlooked by many people just wanting a typical key/value store. Features include:

- Connection pooling to N hosts, with transparent failover and retry of queries
- A low level wrapper for the Thrift interface, much easier to use than the bare Thrift bindings
- Extensive type marshaling, both automatic and custom, so you can force a native integer to be serialised as a string for example
- Struct mapping into Cassandra rows (or row slices), with support for both sparse and compact storage and field name/type overriding
- A high level query interface that deals with structs and mappings instead of rows and column families

Here is an example, using a sparse storage column family with a slice (the equivalent in the current README.md is a bit outdated):

In CQL 3.0:
    UserID varchar,
    TweetID bigint,
    Author varchar,
    Body varchar,
    PRIMARY KEY (UserID, TweetID)

// In Gossie:
type Tweet struct {
    UserID  string `cf:"Timeline" key:"UserID" cols:"TweetID"`
    TweetID int64
    Author  string
    Body    string

pool := gossie.NewConnectionPool([]string{"localhost:9160"}, "Example", PoolOptions{Size: 50, Timeout: 3000})
query := pool.Query(NewMapping(&Tweet{}))

// all tweets for a given user between TweetID 1000 and 2000
result, err := query.Between(1000, 2000).Get("username")

// iterating over results
for {
    t := &Tweet{}
    err := result.Next(t)
    if err != nil {

Key and comparator component marshaling and positions are implicit and automatic, based on the struct mapping, making it very easy to use complex comparators. Also the sparse row support is flexible, in the sense it doesn't depend on a fixed number fields. It is able to detect a new object in the row by discontinuities in the composite values.

Feedback is welcome! Thank you!