auth.go

package spotifyauth

import (
	"context"
	"golang.org/x/oauth2"
	"os"
)

const (
	// AuthURL is the URL to Spotify Accounts Service's OAuth2 endpoint.
	AuthURL = "https://accounts.spotify.com/authorize"
	// TokenURL is the URL to the Spotify Accounts Service's OAuth2
	// token endpoint.
	TokenURL = "https://accounts.spotify.com/api/token"
)

type Authenticator struct {
	config *oauth2.Config
}

type AuthenticatorOption func(a *Authenticator)

func New(opts ...AuthenticatorOption) *Authenticator {
	cfg := &oauth2.Config{
		ClientID:     os.Getenv("SPOTIFY_ID"),
		ClientSecret: os.Getenv("SPOTIFY_SECRET"),
		Endpoint: oauth2.Endpoint{
			AuthURL:  AuthURL,
			TokenURL: TokenURL,
		},
	}

	a := &Authenticator{
		config: cfg,
	}

	for _, opt := range opts {
		opt(a)
	}

	return a
}

func (a Authenticator) RefreshToken(ctx context.Context, token *oauth2.Token) (*oauth2.Token, error) {
	src := a.config.TokenSource(ctx, token)
	return src.Token()
}

// Exchange is like Token, except it allows you to manually specify the access
// code instead of pulling it out of an HTTP request.
func (a Authenticator) Exchange(ctx context.Context, code string, opts ...oauth2.AuthCodeOption) (*oauth2.Token, error) {
	return a.config.Exchange(ctx, code, opts...)
}

// Client creates a *http.Client that will use the specified access token for its API requests.
// Combine this with spotify.HTTPClientOpt.
func (a Authenticator) Client(ctx context.Context, token *oauth2.Token) *http.Client {
	return a.config.Client(ctx, token)
}