option.go

package owl

import (
	"context"
)

// Option is an option for New.
type Option interface {
	Apply(context.Context) context.Context
}

// OptionFunc is a function that implements Option.
type OptionFunc func(context.Context) context.Context

func (f OptionFunc) Apply(ctx context.Context) context.Context {
	return f(ctx)
}

// WithNamespace binds a namespace to the resolver. The namespace is used to
// lookup directive executors. There's a default namespace, which is used when
// the namespace is not specified. The namespace set in New() will be overridden
// by the namespace set in Resolve() or Scan().
func WithNamespace(ns *Namespace) Option {
	return WithValue(ckNamespace, ns)
}

// WithNestedDirectivesEnabled controls whether to resolve nested directives.
// The default value is true. When set to false, the nested directives will not
// be executed. The value set in New() will be overridden by the value set in
// Resolve() or Scan().
func WithNestedDirectivesEnabled(resolve bool) Option {
	return WithValue(ckResolveNestedDirectives, resolve)
}

// WithValue binds a value to the context.
//
// When used in New(), the value is bound to Resolver.Context.
//
// When used in Resolve() or Scan(), the value is bound to
// DirectiveRuntime.Context. See DirectiveRuntime.Context for more details.
func WithValue(key, value interface{}) Option {
	return OptionFunc(func(ctx context.Context) context.Context {
		return context.WithValue(ctx, key, value)
	})
}

func buildContextWithOptionsApplied(ctx context.Context, opts ...Option) context.Context {
	for _, opt := range opts {
		ctx = opt.Apply(ctx)
	}
	return ctx
}