koanf VS viper

LINK: https://github.com/knadh/koanf

For configuration, I like Koanf.

Of course. You should always use a good config package. caarlos0/env is okay but https://github.com/knadh/koanf is a better all around solution imo.

You can also use Viper with urfave/cli, or you can replace Viper with knadh/koanf, which I personally prefer.

Use viper with care. It has some dangerous fundamental flaws [1]. We got bitten hard, submitted a PR [2] and followed up for a year and a half to no avail, before I went ahead and reinvented the wheel and wrote koanf (plug), specifically to avoid viper's flaws.

Most importantly:

- Breaks JSON, YAML, TOML etc. language specs by forcibly lowercasing all keys internally. Dangerous because it can silently merge differently cased config keys into lowercase.

- Hard codes big unnecessary dependencies into the core, significantly bloating build sizes. No separation or abstraction.

[1] https://github.com/spf13/viper/pull/635

[2] https://github.com/knadh/koanf#alternative-to-viper

It's not hard to a) look for a key in an environment variable b) accept a key as a parameter c) load a key from a file d) all of the above with something like koanf

Came across this the other day https://github.com/knadh/koanf as an alternative to Viper.

https://github.com/knadh/koanf for config management. Readme contains why it's a good alternative to viper.

Once environment variables are setup we need load them into our project. For this this i will use viper

The code uses Viper to load configuration files in the application.

github.com/spf13/viper

Instead of directly accessing environment variables with os.Getenv(), integrating a configuration handler like viper might make it maintainable.

I guess most people are using https://github.com/spf13/viper but I don't know if I should read everything from

Use Viper for config file or environmental variable configuration -- it's going to save you a whole lot of time.

Cobra and Viper.

I've mostly been using https://github.com/spf13/viper of late for my go projects. It supports the standard config formats, (json, yaml, toml etc) and lets you override any value with a ENV value.