Support for nested struct environment mapping

[malud]

Currently we are able to map environment variables to configuration structs via tag.

An example:

type Config struct {
  DefaultPort int `env:"default_port"`
}

This gets internally prefixed with COUPER_ and uppercased. The value of COUPER_DEFAULT_PORT will be assigned to Config.DefaultPort.

The following example is not possible at this moment but should:

type Config struct {
  DefaultPort int `env:"default_port"`
  Timings Timings
}

Type Timings struct {
  Timeout time.Duration `env:"timeout"`
}

Env COUPER_TIMEOUT must be assigned to Config.Timings.Timeout.

Related files are config/env/env.go and runtime/http.go makes use of it.

[mohammed786]

Hey @malud ,

Can I take this up as a hacktoberfest task?

[malud]

Sure. Go for it.

[malud]

Since we are calling our env mapping function for related structs directly this is not a requirement anymore.