https://github.com/harrybrwn/config
Just another configuration library for Go
https://github.com/harrybrwn/config
Last synced: 2 months ago
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Just another configuration library for Go
- Host: GitHub
- URL: https://github.com/harrybrwn/config
- Owner: harrybrwn
- License: apache-2.0
- Created: 2020-08-14T19:41:04.000Z (over 4 years ago)
- Default Branch: master
- Last Pushed: 2021-09-10T01:19:51.000Z (over 3 years ago)
- Last Synced: 2025-01-04T11:09:08.022Z (4 months ago)
- Language: Go
- Size: 139 KB
- Stars: 0
- Watchers: 3
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG.md
- License: LICENSE
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README
# Just another config package
This is here because [viper](https://github.com/spf13/viper) didn't work for me
on windows.
## Get Started
Example:
```go
type Config struct {
Host string `yaml:"host" default:"localhost"`
Port int `default:"8080"`
Database struct {
Name string `default:"postgres"`
Port int `default:"5432"`
} `yaml:"database"`
Other string `config:"weird-name"`
}
func main() {
c := &Config{}
config.SetConfig(c)
config.SetType("yaml")
config.AddFile("config.yml") // look for a file named "config.yaml"
config.AddPath(".") // look for the config file in "."
err := config.ReadConfigFile()
if err == config.NoConfigFile {
// handle
}
// Defaults are set
fmt.Println(config.GetInt("port")) // 8080
fmt.Println(config.GetString("database.name")) // postgres
fmt.Println(config.GetString("database.port")) // 5432
// Alternate naming
fmt.Println(config.Get("Other") == config.Get("weird-name")) // true
// Values are also set on the struct
fmt.Println(config.GetInt("port") == c.Port) // true
}
```
## Struct tags
For better of for worse, this library relies on struct tags for customization.
| tag | description |
| --- | ----------- |
| config | change config name and give other info |
| default | give the field a default value |
| env | check this environment variable to get a value |
## Default Values
When initializing a configuration struct, the package will look for the struct
tag called `default` and set the default value from the tag value. This feature
only supports a limited number of types such as string types and integer types.
By default, this feature will only work when using the global "getter"
functions like `config.Get` or `config.GetInt` and **will not work for the
actual struct** that is passed to `config.SetConfig`. To set the default
values to the raw config struct, you need to call `config.InitDefaults`.
## Flag Binding
If you want to change config values using command line options, you can bind
the current config struct to a flag set.
### Struct tags for flag binding
| tag | description | example |
| --- | ----------- | ------- |
| usage | usage for the flag | `config:"name,usage=this is the name flag"` |
| shorthand | give the flag a shorthand (only for pflag) | `config:"name,shorthand=n"` |
| notflag | mark the config field as not a flag | `config:"file,notflag"` |
```go
// test.go
import "flag"
type Config struct {
Name string `config:"name,shorthand=n,usage=give the name"`
Inner struct {
Val int `config:"val,usage=nested flag"`
} `config:"inner"`
}
config.SetConfig(&Config{})
config.BindToFlagSet(
flag.CommandLine,
config.NewFlagInfo("name", "n", "give the name"),
config.NewFlagInfo("inner-val", "", "nested flag"),
)
flag.Parse()
```
Keep in mind that **function call order matters** here. Calling
`config.BindToFlagSet` before `config.SetConfig` means that there is no current
config struct and will most likely result in a nil pointer panic.
```sh
$ go run ./test.go -help
```
```
Usage of /tmp/go-build123456789/b001/exe/test:
-name value
give the name
-inner-val value
nested flag
```
This feature also supports the common flag package drop in replacement called
`github.com/spf13/pflag` and can be accessed using `BindToPFlagSet(set *pflag.FlagSet)`.
The `shorthand` option is only used with this package.