https://github.com/nate-anderson/fig
Juicy config from environment in Go
https://github.com/nate-anderson/fig
config dotenv env environment go godotenv golang
Last synced: 5 months ago
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Juicy config from environment in Go
- Host: GitHub
- URL: https://github.com/nate-anderson/fig
- Owner: nate-anderson
- License: mit
- Created: 2020-09-13T07:44:15.000Z (almost 6 years ago)
- Default Branch: v2
- Last Pushed: 2024-03-12T00:57:23.000Z (over 2 years ago)
- Last Synced: 2025-11-29T23:51:46.178Z (7 months ago)
- Topics: config, dotenv, env, environment, go, godotenv, golang
- Language: Go
- Homepage:
- Size: 267 KB
- Stars: 1
- Watchers: 1
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
README
# fig
[](https://github.com/nate-anderson/fig/actions/workflows/ci.yml)
[](https://goreportcard.com/report/github.com/nate-anderson/fig/v2)
[](https://pkg.go.dev/github.com/nate-anderson/fig/v2)
Juicy extensible config in Go
Fig wraps John Barton's [godotenv](https://github.com/joho/godotenv) with convenience methods for type validation and struct unmarshaling. I wrote this as a subpackage
for another project and extracted it to this repo for easy reuse.
`go get github.com/nate-anderson/fig/v2`
## Initializing
Calling `fig.New()` with no parameters initializes a Config object that reads from the
environment. Passing drivers to `New()` tells `fig` where to check for configuration variables
and your preferred precedence. A driver is any type that allows `fig` to read string values
by key.
A driver for reading from `.env` files is included.
```go
envDriver, err := NewEnvironmentDriver(".env", "local.env")
conf := fig.New(envDriver)
```
`fig.Config` has methods for retrieving `string`s, `int`s, `int64`s, `float64`s and `bool`s.
- GetString
- GetInt
- GetInt64
- GetBool
- GetFloat64
These methods return an `error` if the variable is not configured or if the string in the environment cannot be parsed into the appropriate type. The following methods will panic on missing or malformed variables:
- MustGetString
- MustGetInt
- MustGetInt64
- MustGetBool
- MustGetFloat64
These are useful for required configuration variables for which repeated error checks are a PITA.
For retrieving variables with hard-coded defaults, use the `...Or` set of methods:
- GetStringOr
- GetIntOr
- GetInt64Or
- GetBoolOr
- GetFloatOr
## Struct Unmarshaling
Use the `fig` and `required` struct tags to decorate your configuration structs and quickly
read from your configuration providers. This function makes use of reflection so it is not necessarily optimal for repeated runtime unmarshals.
```go
type Config struct {
DBHost string `fig:"DB_HOST" required:"true"`
DBPort *int `fig:"DB_PORT"`
DBUser string `fig:"DB_USER"`
DBPass *string `fig:"DB_PASS"`
}
var appConfig Config
func init() {
envDriver, _ := NewEnvironmentDriver(".env", "local.env")
conf := fig.New(envDriver)
err := conf.Unmarshal(&appConfig)
}
```
If you need more advanced struct unmarshaling for configuration, I recommend [viper](https://github.com/spf13/viper).