Default values doesn't work (SetDefault function)

[vlkv]

Hi! I'm trying to use default values for my configuration params. They seem to be NOT working. Here is the example:

package main
import (
    "fmt"
    "github.com/spf13/viper"
)

func main() {
    c := viper.New()
    c.SetConfigFile("./config.json")
    c.SetConfigType("json")
    err := c.ReadInConfig()
    if err != nil {
        fmt.Errorf("Error %v\n", err)
    }

    //c.SetTypeByDefaultValue(false)
    c.SetDefault("params.p2", "TWO")
    c.SetDefault("params.p3", "333")

    fmt.Println(c.Get("params.p1"))
    fmt.Println(c.Get("params.p2"))
    fmt.Println(c.Get("params.p3"))
    fmt.Println(c.Get("params.p4"))

    /* Output:
    one   - correct
    two   - correct
    <nil> - WRONG! Expected 333
    <nil> - correct
    */
}

And the config.json is

{
    "params": {
        "p1": "one",
        "p2": "two"
    }
}

[vlkv]

If I'm doing something wrong, please correct my example. Thanks in advance

[kofalt]

I think this is a duplicate of #71. A workaround can be found in that ticket: #71 (comment).

[vlkv]

Thanks for response, but after changing the line

c.SetDefault("params.p3", "333")

with

if c.Get("params.p3") == nil {
            c.SetDefault("params.p3", "333")
    }

It still doesn't work. The output is the same

[jgsqware]

@vlkv Do you find a way to make it work finally?

I made it like that:

if c.Get("params.p3") == nil {
  c.Set("params.p3", "333")
}

[vlkv]

c.Set("params.p3", "333") <<<<< I'd like to do this BEFORE load actual values from file. If I would do this AFTER - then defaults lose their sense, becase I would do this every time in every place after load.

So, I've created my own config module https://github.com/vlkv/ya-go-config It's not as powerfull as viper, it's tiny little simple. But I don't need more.

[jgsqware]

@vlkv I'm reading the conf file before the c.Get()

If Get == nilmeans that the parameter was not in the file. So it set a value.

It's behaviour of default value isn't it?

[vlkv]

#158 (comment) Here is what I've expected

[awfm9]

Fixed by PR #195

[ghost]

func getEnvValue(key string, defaultValue string) string {
value := viper.GetString(key)
if value != "" {
return value
}
return defaultValue
}

[Zanda256]

func getEnvValue(key string, defaultValue string) string {
value := viper.GetString(key)
if value != "" {
return value
}
return defaultValue
}

This surely works.