Move out the token package to util

util/token/jwt/jwt.go

@@ -0,0 +1,110 @@
+package jwt
+
+import (
+	"encoding/base64"
+	"time"
+
+	"github.com/dgrijalva/jwt-go"
+	"github.com/micro/go-micro/v2/auth"
+	"github.com/micro/go-micro/v2/util/token"
+)
+
+// authClaims to be encoded in the JWT
+type authClaims struct {
+	Type     string            `json:"type"`
+	Scopes   []string          `json:"scopes"`
+	Metadata map[string]string `json:"metadata"`
+
+	jwt.StandardClaims
+}
+
+// JWT implementation of token provider
+type JWT struct {
+	opts token.Options
+}
+
+// NewTokenProvider returns an initialized basic provider
+func NewTokenProvider(opts ...token.Option) token.Provider {
+	return &JWT{
+		opts: token.NewOptions(opts...),
+	}
+}
+
+// Generate a new JWT
+func (j *JWT) Generate(acc *auth.Account, opts ...token.GenerateOption) (*token.Token, error) {
+	// decode the private key
+	priv, err := base64.StdEncoding.DecodeString(j.opts.PrivateKey)
+	if err != nil {
+		return nil, err
+	}
+
+	// parse the private key
+	key, err := jwt.ParseRSAPrivateKeyFromPEM(priv)
+	if err != nil {
+		return nil, token.ErrEncodingToken
+	}
+
+	// parse the options
+	options := token.NewGenerateOptions(opts...)
+
+	// generate the JWT
+	expiry := time.Now().Add(options.Expiry)
+	t := jwt.NewWithClaims(jwt.SigningMethodRS256, authClaims{
+		acc.Type, acc.Scopes, acc.Metadata, jwt.StandardClaims{
+			Subject:   acc.ID,
+			Issuer:    acc.Issuer,
+			ExpiresAt: expiry.Unix(),
+		},
+	})
+	tok, err := t.SignedString(key)
+	if err != nil {
+		return nil, err
+	}
+
+	// return the token
+	return &token.Token{
+		Token:   tok,
+		Expiry:  expiry,
+		Created: time.Now(),
+	}, nil
+}
+
+// Inspect a JWT
+func (j *JWT) Inspect(t string) (*auth.Account, error) {
+	// decode the public key
+	pub, err := base64.StdEncoding.DecodeString(j.opts.PublicKey)
+	if err != nil {
+		return nil, err
+	}
+
+	// parse the public key
+	res, err := jwt.ParseWithClaims(t, &authClaims{}, func(token *jwt.Token) (interface{}, error) {
+		return jwt.ParseRSAPublicKeyFromPEM(pub)
+	})
+	if err != nil {
+		return nil, token.ErrInvalidToken
+	}
+
+	// validate the token
+	if !res.Valid {
+		return nil, token.ErrInvalidToken
+	}
+	claims, ok := res.Claims.(*authClaims)
+	if !ok {
+		return nil, token.ErrInvalidToken
+	}
+
+	// return the token
+	return &auth.Account{
+		ID:       claims.Subject,
+		Issuer:   claims.Issuer,
+		Type:     claims.Type,
+		Scopes:   claims.Scopes,
+		Metadata: claims.Metadata,
+	}, nil
+}
+
+// String returns JWT
+func (j *JWT) String() string {
+	return "jwt"
+}