DI engine for Go

[tholowka]

Hello All, 

I have created a small library for providing Dependency Injection in Go. 

Contrary to the other one I saw (https://github.com/facebookgo/inject) the library I've created does not rely on 'annotations' (reminiscent of the encoding/json package). 

It has its own convention and best-practices, which I tried highlighting in the Github README. 

The link to the library is https://github.com/tholowka/octopus.

My personal belief is that to make a product good, the good way is to open source it and have other people, review, test and hammer out bugs. 

If you are interested in this, please drop me a line. I will help you set this up for you if you bump into problems. 

I would appreciate suggestions whether there are bugs, and how to improve the documentation. 

Regards, 

tholowka

[Egon]

I don't understanding what problem this is actually solving.

Taking the example here's one way to write it: http://play.golang.org/p/jQU4x5yKkk

It's much simpler to understand.

Of course there are more ways to write it. e.g. http://play.golang.org/p/1Y2_wxcqQX

+ Egon

[tholowka]

Thank you

I have updated the documentation. I hope it is clearer now.

[Egon]

On Sunday, 1 March 2015 20:26:29 UTC+2, tholowka wrote:

Thank you

I have updated the documentation. I hope it is clearer now.

Sorry, initially I was looking at the wrong link - but the comments still applied to both. :)

One of the problems with DI is that it will make the dependencies less obvious leading to more complicated designs. Regarding the Go example you can write it as:

// some package xxx

var NewHTTPHandler func()http.Handler 

// some package yyy or main

func init(){

xxx.NewHTTPHandler = func() http.Handler {

return &CustomHandler{... dependencies ...}

}

}

// some package zzz

handler := xxx.NewHTTPHandler()

It has similar properties as the DI code and is more idiomatic to Go. The only main difference is that you are not providing the dependencies from JSON - which might be good or bad, depending how you look at it.

+ Egon

[tholowka]

Thank you Egon

I will update the documentation shortly. This is a very interesting example. 

[thwd]

Hi.I invite you to read Jeremy Saenz' thoughts on reflective DI in Go:

http://codegangsta.io/blog/2014/05/19/my-thoughts-on-martini/#martini-reflection-is-flawed:be092bb3a2ecafb4d15d135163b61d62

Best, Tom

[tholowka]

Yes, thank you for both comments. 

I was not familiar with the package approach shown very well by Egon. I did see it one example, with testing, but 

with the approach Egon proposed it actually makes my library redundant. Thank you for making me see this. 

Cheers.