Add error handling to examples

cmd/jwt/main.go

@@ -146,17 +146,17 @@ func verifyToken() error {
 		return data, nil
 	})
 
+	// Print an error if we can't parse for some reason
+	if err != nil {
+		return fmt.Errorf("couldn't parse token: %w", err)
+	}
+
 	// Print some debug data
 	if *flagDebug && token != nil {
 		fmt.Fprintf(os.Stderr, "Header:\n%v\n", token.Header)
 		fmt.Fprintf(os.Stderr, "Claims:\n%v\n", token.Claims)
 	}
 
-	// Print an error if we can't parse for some reason
-	if err != nil {
-		return fmt.Errorf("couldn't parse token: %w", err)
-	}
-
 	// Is token invalid?
 	if !token.Valid {
 		return fmt.Errorf("token is invalid")
@@ -274,7 +274,7 @@ func showToken() error {
 	}
 
 	token, err := jwt.Parse(string(tokData), nil)
-	if token == nil {
+	if err != nil || token == nil {
 		return fmt.Errorf("malformed token: %w", err)
 	}
 

example_test.go

@@ -3,6 +3,7 @@ package jwt_test
 import (
 	"errors"
 	"fmt"
+	"log"
 	"time"
 
 	"github.com/golang-jwt/jwt/v5"
@@ -86,6 +87,9 @@ func ExampleParseWithClaims_customClaimsType() {
 	token, err := jwt.ParseWithClaims(tokenString, &MyCustomClaims{}, func(token *jwt.Token) (interface{}, error) {
 		return []byte("AllYourBase"), nil
 	})
+	if err != nil {
+		log.Fatal(err)
+	}
 
 	if claims, ok := token.Claims.(*MyCustomClaims); ok && token.Valid {
 		fmt.Printf("%v %v", claims.Foo, claims.RegisteredClaims.Issuer)
@@ -109,6 +113,9 @@ func ExampleParseWithClaims_validationOptions() {
 	token, err := jwt.ParseWithClaims(tokenString, &MyCustomClaims{}, func(token *jwt.Token) (interface{}, error) {
 		return []byte("AllYourBase"), nil
 	}, jwt.WithLeeway(5*time.Second))
+	if err != nil {
+		log.Fatal(err)
+	}
 
 	if claims, ok := token.Claims.(*MyCustomClaims); ok && token.Valid {
 		fmt.Printf("%v %v", claims.Foo, claims.RegisteredClaims.Issuer)
@@ -144,6 +151,9 @@ func ExampleParseWithClaims_customValidation() {
 	token, err := jwt.ParseWithClaims(tokenString, &MyCustomClaims{}, func(token *jwt.Token) (interface{}, error) {
 		return []byte("AllYourBase"), nil
 	}, jwt.WithLeeway(5*time.Second))
+	if err != nil {
+		log.Fatal(err)
+	}
 
 	if claims, ok := token.Claims.(*MyCustomClaims); ok && token.Valid {
 		fmt.Printf("%v %v", claims.Foo, claims.RegisteredClaims.Issuer)
@@ -162,6 +172,9 @@ func ExampleParse_errorChecking() {
 	token, err := jwt.Parse(tokenString, func(token *jwt.Token) (interface{}, error) {
 		return []byte("AllYourBase"), nil
 	})
+	if err != nil {
+		log.Fatal(err)
+	}
 
 	if token.Valid {
 		fmt.Println("You look nice today")

hmac_example_test.go

@@ -2,6 +2,7 @@ package jwt_test
 
 import (
 	"fmt"
+	"log"
 	"os"
 	"time"
 
@@ -56,6 +57,9 @@ func ExampleParse_hmac() {
 		// hmacSampleSecret is a []byte containing your secret, e.g. []byte("my_secret_key")
 		return hmacSampleSecret, nil
 	})
+	if err != nil {
+		log.Fatal(err)
+	}
 
 	if claims, ok := token.Claims.(jwt.MapClaims); ok && token.Valid {
 		fmt.Println(claims["foo"], claims["nbf"])

http_example_test.go

@@ -84,9 +84,7 @@ func Example_getTokenViaHTTP() {
 		"user": {"test"},
 		"pass": {"known"},
 	})
-	if err != nil {
-		fatal(err)
-	}
+	fatal(err)
 
 	if res.StatusCode != 200 {
 		fmt.Println("Unexpected status code", res.StatusCode)