omnifroodle / cass

Cassandra client for Go

A simple Cassandra client in go. Currently runs against cassandra 1.2.x

Alternate go clients to consider

• https://github.com/carloscm/gossie
• https://github.com/tux21b/gocql
• Or, a go cassandra connection pooling service https://github.com/samuraisam/cassbounce

Installation

First get a working version of Thrift Go Lib .

go get github.com/pomack/thrift4go/lib/go/src/thrift

# then install the go cass

go get github.com/araddon/cass

Documentation

See full doc here: http://godoc.org/github.com/araddon/cass

Usage

CQL:

err, err1 := conn.Client.SetCqlVersion("3.0.0")
if err != nil || err1 != nil {
  log.Println(err, err1)
}

res, err2 := conn.Query(`
  CREATE TABLE user (
    customerid int,
    uid int,
    gob blob,
    PRIMARY KEY (customerid, uid)
  );`)

if err2 != nil {
  log.Println("CQL Query create failed by returning error ", err)
}

cql := fmt.Sprintf(`INSERT INTO user (customerid, uid, gob) VALUES (1234,128,'%#x');`, "gobdata")

if _, err3 := conn.Query(cql); err3 != nil {
  log.Println("CQL Query Insert failed by returning error ", err3)
}


rows, err4 := conn.Query("SELECT * FROM user WHERE customerid=1234;")

if len(rows) != 1 {
  log.Printf("Query failed was %v \n", rows)
}

Thrift Interface

Create a Connection, Keyspace, Column Family, Insert, Read:

import "github.com/araddon/cass", "fmt"
func main() {

  cass.ConfigKeyspace("testing",[]string{"127.0.0.1:9160"}, 20 )
  conn, _ = cass.GetCassConn("testing")
  // since there is a pool of connections, you must checkin
  defer conn.Checkin()

  // 1 is replication factor, will return err if it already exists
  _ = conn.CreateKeyspace("testing",1)

  _ = conn.CreateCF("col_fam_name")

  // if you pass 0 timestamp it will generate one
  err := conn.Insert("col_fam_name","keyinserttest",map[string]string{"lastname": "golang"},0)
  if err != nil {
    fmt.Println("error, insert/read failed")
  }

  col, _ := conn.Get("col_fam_name","keyinserttest","lastname")
  if col == nil && col.Value != "cassgo" {
    fmt.Println("insert/get single row, single col failed: testcol - keyinserttest")
  }
}

Inserting more than one row:

rows := map[string]map[string]string{
  "keyvalue1": map[string]string{"col1":"val1","col2": "val2"},
  "keyvalue2": map[string]string{"col1":"val1","col2": "val2"},
}

// 0 is the int64 NanoSecond timestamp, if you pass 0 it will generate
err := conn.Mutate("col_fam_name",rows,0)

// equivalent to
err := conn.Mutate("col_fam_name",rows,time.Now().UnixNano())

if err != nil {
  t.Errorf("error, insert/read failed on multicol insert")
}

Counter Columns:

_ = conn.CreateCounterCF("testct")// testct is a column family name

_ = conn.Add("testct","keyinserttest",int64(9))
_ = conn.Add("testct","keyinserttest",int64(10))

ct := conn.GetCounter("testct","keyinserttest")

if ct != int64(19) {
  fmt.Println("Crap, counter didn't work and equal 19", ct)
}

Get Many for column family, and row key specified return columns:

// get all columns by all, all = ct specified
// true = "reversed", start from last column
colsall, errall := conn.GetAll("col_fam_name","keyvalue1", true,1000)

// get Range (start/end) column comparator determines how start/end determined, also
//   reversed (start at last row), and col limit ct
cols, err2 := conn.GetRange("col_fam_name","keyvalue1","col2","col3", false, 100)

// get specific cols
cols2, err3 := conn.GetCols("col_fam_name","keyvalue1",[]string{"col2","col4"})