DInit

DInit is a library to initialize structs using Dependenci Injection (DI).

Installation

go get -u github.com/lsegal/dinit

Usage

Use dinit.Init(val1, val2, ...) where arguments are either struct values, references, bare functions, or initializer functions that return struct values.

DInit will then call your functions in the appropriate order to ensure that all functions have their arguments filled by the values provided in the Init() call.

For example, in the code below we have a log.Logger object, a client and service. The service depends on log.Logger, and client depends on both service and log.Logger. When we call their initializers, only 1 instance of client and server are created:

func newClient(l *log.Logger, svc lister) *client { /* ... */ }
func newService(l *log.Logger) *service { /* ... */ }

func main() {
  l := log.New(os.Stdout, "", log.Lshortfile)
  useClient := func(c *client) { c.PrintPeople() }
  dinit.Init(newClient, useClient, newService, l)

  // Output:
  // main.go:40: Initializing service
  // main.go:35: Initializing client
  // main.go:30: Client asked for a list of people
  // main.go:18: People: Sarah, Bob, André
}

You can see the full (runnable) example in examples/client_server/main.go.

Copyright & License

Copyright (c) 2018 Loren Segal. All rights reserved.

This project is licensed under the MIT license, see LICENSE for details.