initialization

README

initialization

Is a package for initialization of the application modules. Ex. database connectors, service providers, etc.

Usage

package main

import (
	"errors"
	"log"
	"time"

	"git.ooo.ua/pub/armory/initialization"
	"github.com/sirupsen/logrus"
)

func main() {
	moduleList := initialization.Modules{
		initialization.Module{
			Name:         "database_conn",
			DependsOn:    "",
			Timeout:      15 * time.Second,
			InitInterval: time.Second,
			Init: func(entry *logrus.Entry) error {
				entry.WithField("module", "database_conn").
					Info("try to initialize module")
				time.Sleep(500 * time.Millisecond)
				return errors.New("ha-ha-ha")
			},
		},

		initialization.Module{
			Name:         "rabbit",
			DependsOn:    "",
			Timeout:      15 * time.Second,
			InitInterval: time.Second,
			Init: func(entry *logrus.Entry) error {
				entry.WithField("module", "rabbit").
					Info("try to initialize module")
				time.Sleep(500 * time.Millisecond)
				return nil
			},
		},

		initialization.Module{
			Name:         "listener",
			DependsOn:    "database_conn",
			Timeout:      15 * time.Second,
			InitInterval: time.Second,
			Init: func(entry *logrus.Entry) error {
				entry.WithField("module", "listener").
					Info("try to initialize module")
				time.Sleep(500 * time.Millisecond)
				return nil
			},
		},
	}

	err := moduleList.InitAll()
	if err != nil {
		log.Fatal("Init failed with error: ", err.Error())
	}
}

Documentation

Overview

Example

moduleList := Modules{
	Module{
		Name:         "database_conn",
		DependsOn:    "",
		Timeout:      15 * time.Second,
		InitInterval: time.Second,
		Init: func(entry *logrus.Entry) error {
			entry.WithField("module", "database_conn").
				Info("try to initialize module")
			time.Sleep(500 * time.Millisecond)
			return errors.New("ha-ha-ha")
		},
	},

	Module{
		Name:         "rabbit",
		DependsOn:    "",
		Timeout:      15 * time.Second,
		InitInterval: time.Second,
		Init: func(entry *logrus.Entry) error {
			entry.WithField("module", "rabbit").
				Info("try to initialize module")
			time.Sleep(500 * time.Millisecond)
			return nil
		},
	},

	Module{
		Name:         "listener",
		DependsOn:    "database_conn",
		Timeout:      15 * time.Second,
		InitInterval: time.Second,
		Init: func(entry *logrus.Entry) error {
			entry.WithField("module", "listener").
				Info("try to initialize module")
			time.Sleep(500 * time.Millisecond)
			return nil
		},
	},
}

err := moduleList.InitAll()
if err != nil {
	log.Fatal("Init failed with error: ", err.Error())
}

Index

• type Module
  • func (mod *Module) Run(locks map[string]chan bool) error
• type Modules
  • func (modules Modules) Add(m *Module) Modules
  • func (modules Modules) InitAll() error

Examples

• Package

Types

type Module

type Module struct {
	// Name unique identifier for module.
	Name string
	// DependsOn is a name of other module which should be initialized before this.
	DependsOn string
	// InitInterval is initial timeout before second attempt to perform initCall.
	InitInterval time.Duration
	// Timeout is a deadline for the initialization attempts.
	Timeout time.Duration
	// Init is a module init function.
	Init func(*logrus.Entry) error
}

Module is unit for initialization.

func (*Module) Run

func (mod *Module) Run(locks map[string]chan bool) error

Run tries to initialize the module, if the attempt failed, it will be repeated, but with an incremental delay. So it will be until the maximum initialization timeout is reached.

type Modules

type Modules []Module

Modules is a set of modules for initialization.

func (Modules) Add

func (modules Modules) Add(m *Module) Modules

Add push new module to set.

func (Modules) InitAll

func (modules Modules) InitAll() error

InitAll checks status and run initialization of all modules for the fist to last.