Geek

Geek is a kdb+/q interface for Go (Golang). It comes with a kdb+/q load balancer ConnPool, which uses a buffered channel to handle the connections pool.

• ConnPool.Handle
  • doesn't serialize or deserialize IPC message.
  • before passing on IPC messages, define .geek.user and .geek.ip on the q process
• ConnPool.Sync
  • need a known go type pointer as an parameter

Contents

• Installation
• Quick Start
• Data Types

Installation

1. Install Geek

go get -u github.com/jshinonome/geek

2. Import it in your code

import "github.com/jshinonome/geek"

Quick Start

Load balancer

1. Create an example.go file as below

package main

import "github.com/jshinonome/geek"

func main() {
	// connect to a q process @ 1800
	q1 := geek.QProcess{Port: 1800}
	q1.Dial()
	// connect to a q process @ 1801
	q2 := geek.QProcess{Port: 1801}
	q2.Dial()
	qConnPool := geek.NewConnPool()
	qConnPool.Put(&q1)
	qConnPool.Put(&q2)
	qConnPool.Serving()

	qEngine := geek.DefaultEngine(qConnPool)
	qEngine.Run() // listen and server on :8101
}

2. Start two q processes

q -p 1800

q -p 1801

3. Run the q Engine

go run example.go

4. Start a new q process and run queries(geek.Engine doesn't keep client connection, so don't try to open a handle)

`::8101 ("system";"p") //1800
`::8101 ("system";"p") //1801

Interface with q process

1. Create an example.go file as below

package main

import (
	"fmt"
	"time"

	"github.com/jshinonome/geek"
)

func main() {
	// connect to a q process @ 1800
	q := geek.QProcess{Port: 1800}
	q.Dial()
	sym := "a"
	f := struct {
		Api string
		Sym string
	}{
		"getTrade", sym,
	}
	r := make([]trade, 0)
	err := q.Sync(&r, f)
	if err != nil {
		fmt.Println(err)
	}
	for _, t := range r {
		fmt.Printf("%+v\n", t)
	}
}

type trade struct {
	Time  time.Time `k:"time"`
	Sym   string    `k:"sym"`
	Price float64   `k:"price"`
	Qty   int64     `k:"qty"`
}

2. Start a q process

q -p 1800
trade:([]time:"p"$.z.D-til 10;sym:10?`a`b;price:10?10.0;qty:10?10);
getTrade:{select from trade where sym=x};
.z.pg:{[x]0N!(`zpg;x);value x};

3. Run go program

go run example.go

Data Types

Basic Types

Intend to support only these 6 types

kdb	go
long	int64
float	float64
char	byte
symbol	string
timestamp	time.Time
boolean	bool

Other Types

go struct without k tags -> k mixed list

struct {
	Func   string
	Param1 string
	Param2 string
}

go map -> k dictionary

map[string]bool

go struct with k tags(keys' name) -> k dictionary

struct {
	Key1 string    `k:"sym"`
	Key2 time.Time `k:"time"`
	Key3 float64   `k:"qty"`
}

go list of a struct with k tags(column names) -> k table

[]struct {
	Sym  string    `k:"sym"`
	Time time.Time `k:"time"`
	Qty  float64   `k:"qty"`
}