Tarantool client in Go language

The tarantool package allows communicating with Tarantool 1.7.1+.

This is an opinionated modification of github.com/tarantool/go-tarantool package. The original license kept unchanged here at the moment.

Differences from the original package

• API changed, some non-obvious (mostly to me personally) API removed.
• This package uses the latest msgpack library github.com/vmihailenco/msgpack/v5 instead of v2 in original.
• Uses UseArrayEncodedStructs(true) for msgpack.Encoder by default so there is no need to define msgpack:",as_array" struct tags. If you need to disable this (for example when using nested structs) then this behavior can be disabled using DisableArrayEncodedStructs option.
• Uses UseLooseInterfaceDecoding(true) for msgpack.Decoder to decode response into untyped []interface{} result. See decoding rules.
• Supports out-of-bound pushes (see box.session.push)
• Adds optional support for context.Context (though performance will suffer a bit, if you want a maximum performance then use non-context methods which use per-connection timeout). Context cancellation does not cancel a query (Tarantool has no such functionality) - just stops waiting for request future resolving.
• Uses sync.Pool for *msgpack.Decoder to reduce allocations on decoding stage a bit. Actually this package allocates a bit more than the original one, but allocations are small and overall performance is comparable to the original (based on observations from internal benchmarks).
• No multi and queue packages.
• Only one version of Call which uses Tarantool 1.7 request code.
• Modified connection address behavior: refer to Connect function docs to see details.
• Per-request timeout detached from underlying connection read and write timeouts.
• Op type to express different update/upsert operations.
• Some other cosmetic changes including several linter fixes.
• No default Logger – developer needs to provide custom implementation explicitly.

The networking core of github.com/tarantool/go-tarantool kept mostly unchanged at the moment so this package should behave in similar way.

Installation

$ go get github.com/FZambia/tarantool

Status

This library is a prototype for Centrifuge/Centrifugo ongoing Tarantool Engine experiment.

API is not stable here and can have changes as experiment evolves. Also, there are no concrete plans at the moment regarding the package maintenance.

The versioning politics before v1 will be the following: patch version updates will only contain backwards compatible changes, minor version updates may have backwards incompatible changes.

Quick start

Create example.lua file with content:

box.cfg{listen = 3301}
box.schema.space.create('examples', {id = 999})
box.space.examples:create_index('primary', {type = 'hash', parts = {1, 'unsigned'}})
box.schema.user.grant('guest', 'read,write', 'space', 'examples')

Run it with Tarantool:

tarantool example.lua

Then create main.go file:

package main

import (
	"log"
	"time"

	"github.com/FZambia/tarantool"
)

type Row struct {
	ID    uint64
	Value string
}

func main() {
	opts := tarantool.Opts{
		RequestTimeout: 500 * time.Millisecond,
		User:           "guest",
	}
	conn, err := tarantool.Connect("127.0.0.1:3301", opts)
	if err != nil {
		log.Fatalf("Connection refused: %v", err)
	}
	defer func() { _ = conn.Close() }()

	_, err = conn.Exec(tarantool.Insert("examples", Row{ID: 999, Value: "hello"}))
	if err != nil {
		log.Fatalf("Insert failed: %v", err)
	}
	log.Println("Insert succeeded")
}

Finally, run it with:

go run main.go