Documentation
¶
Overview ¶
Package config provides an application configuration system.
Usage
First, config need to initialize at the beginning.
if err := config.Init(); err != nil {
// Handle error.
}
Then to read config, just unmarshal it to a struct or map:
cfg := serverConfig
Port: 8080,
Name: "default",
}
if err := config.Unmarshal("server", &ac); err != nil {
// handle error
}
Configuration Source ¶
It loads configuration from the following sources. Each item takes precedence over the item below it:
- command line flag if it's defined like below: flag.String("foo.bar", "default value", "config `bar`")
- environment variables which matches the following format: prefix + "_" + the key name in ALL CAPS. For example, FOO_BAR is the name of environment variable to foo.bar.
- config file specified by WithFile and WithFS.
Index ¶
Examples ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func Unmarshal ¶
Unmarshal unmarshalls the config with prefix into a (embedded) struct pointed to by target.
It also supports unmarshaling values which uses mapstructure tags by default. See https://github.com/mitchellh/mapstructure.
Example ¶
package main
import (
"fmt"
"os"
"github.com/ktong/nilgo/config"
)
func main() {
_ = os.Setenv("SOURCE", "env")
defer os.Clearenv()
_ = config.Init()
var c struct {
Source string
}
_ = config.Unmarshal("", &c)
fmt.Println(c.Source)
}
Output: env
Types ¶
type Option ¶
type Option func(*options)
Option configures how it loads application configuration.
func WithFile ¶
WithFile explicitly defines the path, name of the config file.
Example ¶
package main
import (
"fmt"
"testing/fstest"
"github.com/ktong/nilgo/config"
)
func main() {
mapFS := fstest.MapFS{
"config.yaml": {
Data: []byte("file:\n source: embed"),
},
}
_ = config.Init(
config.WithFile("config.yaml"),
config.WithFS(mapFS),
)
var source string
_ = config.Unmarshal("file.source", &source)
fmt.Println(source)
}
Output: embed
Source Files
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