Using multi-stage builds to reduce container image size

[sleeping-barber]

Hi Adam, I was looking into your project which looks very promising to me on a technical level but also to learn about a lot of coding principles.

Trying to build the Container Image locally I was running into a couple of problems.

• The go.mod file referenced Go 1.12 which doesn't support the new error handling error.As for example and one of your dependencies is using it.
• The manifest of the container image couldn't be build due to missing of the GO111MODULE needed to be set to "On" or "Auto" (AFAIK :) ).

So I thought improving it to reduce the size from 881MB to 18.2MB.

I used multi-stage builds and instead of using go get, I thought it would be easier to just copy the code already there on the local machine (so we don't to grab it again).

Thoughts and ideas are more then welcomed, Take care!

[adamluzsi]

Hi Camal Cakar (@midnightrun),

First of all, thank you so much for spending your time on this, you just made my day!!! Wow, I found your solution for the Dockerfile super neat! I didn't know about multi-stage builds, and I was thinking about using the scratch with precompiled content, but I didn't wanted to have a custom build script for my Dockerfile, so I trashed the idea. And look at what you made, in my opinion, the best of both worlds without any custom build script! I'm super happy because of your PR!

Thank you so much! Feel free yo ask if you interested about anything in the project!

Cheers, Adam