firasdarwish/ore

package main

import (
    "context"
    "fmt"

    "github.com/firasdarwish/ore"
)

type SomeService struct {
    someConfig string
}

func main() {
    //register SomeService which depends on "someConfig"
    ore.RegisterFunc[*SomeService](ore.Scoped, func(ctx context.Context) (*SomeService, context.Context) {
        someConfig, ctx := ore.GetKeyed[string](ctx, "someConfig")
        return &SomeService{someConfig}, ctx
    })

    //someConfig is unknown at registration time
    //the value of "someConfig" depends on the future user's request
    ore.RegisterKeyedPlaceholder[string]("someConfig")

    //Seal registration, no further registration is allowed
    ore.Seal()
    ore.Validate()

    //a request arrive
    ctx := context.Background()
    //suppose that the request is sent by "admin"
    ctx = context.WithValue(ctx, "role", "admin")

    //inject a different config depends on the request,
    userRole := ctx.Value("role").(string)
    if userRole == "admin" {
        ctx = ore.ProvideKeyedScopedValue(ctx, "Admin config", "someConfig")
    } else if userRole == "supervisor" {
        ctx = ore.ProvideKeyedScopedValue(ctx, "Supervisor config", "someConfig")
    } else if userRole == "user" {
        ctx = ore.ProvideKeyedScopedValue(ctx, "Public user config", "someConfig")
    }

    service, _ := ore.Get[*SomeService](ctx)
    fmt.Println(service.someConfig) //"Admin config"
}