openapi-nexus 0.1.3

package runtime

import (
	"encoding/base64"
	"fmt"
	"net/http"
)

// Authenticator attaches credentials to an outgoing request.
//
// Return a non-nil error to abort the request before it leaves the client.
type Authenticator interface {
	AuthenticateRequest(req *http.Request) error
}

// BearerAuth sends `Authorization: Bearer <Token>`.
type BearerAuth struct {
	Token string
}

func (b BearerAuth) AuthenticateRequest(req *http.Request) error {
	if b.Token == "" {
		return fmt.Errorf("bearer auth: empty token")
	}
	req.Header.Set("Authorization", "Bearer "+b.Token)
	return nil
}

// APIKeyLocation enumerates where an API key is placed on the wire.
type APIKeyLocation int

const (
	APIKeyInHeader APIKeyLocation = iota
	APIKeyInQuery
	APIKeyInCookie
)

// APIKeyAuth attaches a named API key to a request.
type APIKeyAuth struct {
	Key      string
	Name     string
	Location APIKeyLocation
}

func (a APIKeyAuth) AuthenticateRequest(req *http.Request) error {
	if a.Key == "" || a.Name == "" {
		return fmt.Errorf("api key auth: empty key or name")
	}
	switch a.Location {
	case APIKeyInHeader:
		req.Header.Set(a.Name, a.Key)
	case APIKeyInQuery:
		q := req.URL.Query()
		q.Set(a.Name, a.Key)
		req.URL.RawQuery = q.Encode()
	case APIKeyInCookie:
		req.AddCookie(&http.Cookie{Name: a.Name, Value: a.Key})
	default:
		return fmt.Errorf("api key auth: unknown location %d", a.Location)
	}
	return nil
}

// BasicAuth sends `Authorization: Basic <base64(user:pass)>`.
type BasicAuth struct {
	Username string
	Password string
}

func (b BasicAuth) AuthenticateRequest(req *http.Request) error {
	creds := b.Username + ":" + b.Password
	encoded := base64.StdEncoding.EncodeToString([]byte(creds))
	req.Header.Set("Authorization", "Basic "+encoded)
	return nil
}