confobject

ConfObject

Reloadable, validated configuration from many - sometimes uncontrollable - sources

Motivation

I had to deal with configuration values that came from a lot of different places and circumstances:

• a config file or env vars
• some json or yaml file - possibly stored in a db
• some of these i had control over - others could be modified by a user in an app that i do not necessarily must have access to to employ validation or control the way things are stored

I also needed:

• default values, "NOT NULL" like constraints, and validation that involves dependencies between different config values
• the ability to reload the configs from all its sources in its original order in an easy way

Features

Usage

Cfg := struct {
	Config

	BoolSetting   bool    `default:"true"`
	StringSetting string  `default:"foo" json:"string_setting"`
	IntSetting    int     `required:"false" default:"23" should:"BeGreaterThanOrEqualTo_FloatSetting"`
	FloatSetting  float64 `default:"1.681"`

	SingleValueConfig struct {
		StringSetting string  `default:"bar" json:"single_value_config__string_setting"`
		IntSetting    int     `required:"false" default:"42" should:"BeGreaterThanOrEqualTo_.FloatSetting"`
		FloatSetting  float64 `should:"BeLessThanOrEqualTo_IntSetting"`
	}

	SliceConfig struct {
		StringSliceSetting []string  `default:"foo,bar"`
		IntSliceSetting    []int     `default:"23,42"`
		FloatSliceSetting  []float64 `default:"1.394,1.112"`
	}

	NestedValueConfig struct {
		StringSetting          string `default:"NestedOuterFoo"`
		InnerNestedValueConfig struct {
			StringSetting string `default:"NestedInnerFoo"`
		}
	}

	StringSet *set.StringSet `alias:someNameICantControl`
	IntSet    *set.IntSet
}{}

err = cobj.InitConfig(&Cfg, []cobj.InitFunc{
	cobj.InitFunc{
		F:           loadConfFile,
		ExitOnError: true,
	},
	cobj.InitFunc{
		F:           setupThisOtherThing,
		ExitOnError: false,
	},
}...)


func loadConfFile() (err error) {
	conf := make(map[string]string)

    ...

	err = Cfg.Set(conf)
	return
}

Limitations

TODOs

• finish writing this file
• godoc
• clean up and extend the tests

Questions?

Ping me on twitter