Return old hmac examples to the hmac_example_test

Just to satisfy the gods of coverage.

hmac_example_test.go

@@ -1,6 +1,7 @@
 package jwt_test
 
 import (
+	"errors"
 	"fmt"
 	"os"
 	"time"
@@ -65,3 +66,129 @@ func ExampleParse_hmac() {
 
 	// Output: bar 1.4444784e+09
 }
+
+// Example creating a token using a custom claims type. The RegisteredClaims is embedded
+// in the custom type to allow for easy encoding, parsing and validation of registered claims.
+func ExampleNewWithClaims_customClaimsTypeHmac() {
+	mySigningKey := []byte("AllYourBase")
+
+	type SomeCustomClaims struct {
+		Foo string `json:"foo"`
+		jwt.RegisteredClaims
+	}
+
+	// Create claims with multiple fields populated
+	claims := SomeCustomClaims{
+		"bar",
+		jwt.RegisteredClaims{
+			// A usual scenario is to set the expiration time relative to the current time
+			ExpiresAt: jwt.NewNumericDate(time.Now().Add(24 * time.Hour)),
+			IssuedAt:  jwt.NewNumericDate(time.Now()),
+			NotBefore: jwt.NewNumericDate(time.Now()),
+			Issuer:    "test",
+			Subject:   "somebody",
+			ID:        "1",
+			Audience:  []string{"somebody_else"},
+		},
+	}
+
+	fmt.Printf("foo: %v\n", claims.Foo)
+
+	// Create claims while leaving out some of the optional fields
+	claims = SomeCustomClaims{
+		"bar",
+		jwt.RegisteredClaims{
+			// Also fixed dates can be used for the NumericDate
+			ExpiresAt: jwt.NewNumericDate(time.Unix(1516239022, 0)),
+			Issuer:    "test",
+		},
+	}
+
+	token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
+	ss, err := token.SignedString(mySigningKey)
+	fmt.Printf("%v %v", ss, err)
+
+	//Output: foo: bar
+	//eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJmb28iOiJiYXIiLCJpc3MiOiJ0ZXN0IiwiZXhwIjoxNTE2MjM5MDIyfQ.xVuY2FZ_MRXMIEgVQ7J-TFtaucVFRXUzHm9LmV41goM <nil>
+}
+
+// Example creating a token using a custom claims type.  The RegisteredClaims is embedded
+// in the custom type to allow for easy encoding, parsing and validation of standard claims.
+func ExampleParseWithClaims_customClaimsTypeHmac() {
+	tokenString := "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJmb28iOiJiYXIiLCJpc3MiOiJ0ZXN0IiwiYXVkIjoic2luZ2xlIn0.QAWg1vGvnqRuCFTMcPkjZljXHh8U3L_qUjszOtQbeaA"
+
+	type SomeCustomClaims struct {
+		Foo string `json:"foo"`
+		jwt.RegisteredClaims
+	}
+
+	token, err := jwt.ParseWithClaims(tokenString, &SomeCustomClaims{}, func(token *jwt.Token) (interface{}, error) {
+		return []byte("AllYourBase"), nil
+	})
+
+	if claims, ok := token.Claims.(*SomeCustomClaims); ok && token.Valid {
+		fmt.Printf("%v %v", claims.Foo, claims.RegisteredClaims.Issuer)
+	} else {
+		fmt.Println(err)
+	}
+
+	// Output: bar test
+}
+
+// Example creating a token using a custom claims type and validation options.  The RegisteredClaims is embedded
+// in the custom type to allow for easy encoding, parsing and validation of standard claims.
+func ExampleParseWithClaims_validationOptionsHmac() {
+	tokenString := "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJmb28iOiJiYXIiLCJpc3MiOiJ0ZXN0IiwiYXVkIjoic2luZ2xlIn0.QAWg1vGvnqRuCFTMcPkjZljXHh8U3L_qUjszOtQbeaA"
+
+	type SomeCustomClaims struct {
+		Foo string `json:"foo"`
+		jwt.RegisteredClaims
+	}
+
+	token, err := jwt.ParseWithClaims(tokenString, &SomeCustomClaims{}, func(token *jwt.Token) (interface{}, error) {
+		return []byte("AllYourBase"), nil
+	}, jwt.WithLeeway(5*time.Second))
+
+	if claims, ok := token.Claims.(*SomeCustomClaims); ok && token.Valid {
+		fmt.Printf("%v %v", claims.Foo, claims.RegisteredClaims.Issuer)
+	} else {
+		fmt.Println(err)
+	}
+
+	// Output: bar test
+}
+
+type SomeCustomClaims struct {
+	Foo string `json:"foo"`
+	jwt.RegisteredClaims
+}
+
+// Validate can be used to execute additional application-specific claims
+// validation.
+func (m SomeCustomClaims) Validate() error {
+	if m.Foo != "bar" {
+		return errors.New("must be foobar")
+	}
+
+	return nil
+}
+
+// Example creating a token using a custom claims type and validation options.
+// The RegisteredClaims is embedded in the custom type to allow for easy
+// encoding, parsing and validation of standard claims and the function
+// CustomValidation is implemented.
+func ExampleParseWithClaims_customValidationHmac() {
+	tokenString := "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJmb28iOiJiYXIiLCJpc3MiOiJ0ZXN0IiwiYXVkIjoic2luZ2xlIn0.QAWg1vGvnqRuCFTMcPkjZljXHh8U3L_qUjszOtQbeaA"
+
+	token, err := jwt.ParseWithClaims(tokenString, &SomeCustomClaims{}, func(token *jwt.Token) (interface{}, error) {
+		return []byte("AllYourBase"), nil
+	}, jwt.WithLeeway(5*time.Second))
+
+	if claims, ok := token.Claims.(*SomeCustomClaims); ok && token.Valid {
+		fmt.Printf("%v %v", claims.Foo, claims.RegisteredClaims.Issuer)
+	} else {
+		fmt.Println(err)
+	}
+
+	// Output: bar test
+}