feat(auth): add get-access-token cmd (#598)

relates to STACKITCLI-11

Author: Ruben Hönle

docs/stackit_auth.md

@@ -31,6 +31,7 @@ stackit auth [flags]
 
 * [stackit](./stackit.md)	 - Manage STACKIT resources using the command line
 * [stackit auth activate-service-account](./stackit_auth_activate-service-account.md)	 - Authenticates using a service account
+* [stackit auth get-access-token](./stackit_auth_get-access-token.md)	 - Prints a short-lived access token.
 * [stackit auth login](./stackit_auth_login.md)	 - Logs in to the STACKIT CLI
 * [stackit auth logout](./stackit_auth_logout.md)	 - Logs the user account out of the STACKIT CLI
 

docs/stackit_auth_get-access-token.md

@@ -0,0 +1,40 @@
+## stackit auth get-access-token
+
+Prints a short-lived access token.
+
+### Synopsis
+
+Prints a short-lived access token which can be used e.g. for API calls.
+
+```
+stackit auth get-access-token [flags]
+```
+
+### Examples
+
+```
+  Print a short-lived access token
+  $ stackit auth get-access-token
+```
+
+### Options
+
+```
+  -h, --help   Help for "stackit auth get-access-token"
+```
+
+### Options inherited from parent commands
+
+```
+  -y, --assume-yes             If set, skips all confirmation prompts
+      --async                  If set, runs the command asynchronously
+  -o, --output-format string   Output format, one of ["json" "pretty" "none" "yaml"]
+  -p, --project-id string      Project ID
+      --region string          Target region for region-specific requests
+      --verbosity string       Verbosity of the CLI, one of ["debug" "info" "warning" "error"] (default "info")
+```
+
+### SEE ALSO
+
+* [stackit auth](./stackit_auth.md)	 - Authenticates the STACKIT CLI
+

internal/cmd/auth/auth.go

@@ -2,6 +2,7 @@ package auth
 
 import (
 	activateserviceaccount "github.com/stackitcloud/stackit-cli/internal/cmd/auth/activate-service-account"
+	getaccesstoken "github.com/stackitcloud/stackit-cli/internal/cmd/auth/get-access-token"
 	"github.com/stackitcloud/stackit-cli/internal/cmd/auth/login"
 	"github.com/stackitcloud/stackit-cli/internal/cmd/auth/logout"
 	"github.com/stackitcloud/stackit-cli/internal/pkg/args"
@@ -27,4 +28,5 @@ func addSubcommands(cmd *cobra.Command, p *print.Printer) {
 	cmd.AddCommand(login.NewCmd(p))
 	cmd.AddCommand(logout.NewCmd(p))
 	cmd.AddCommand(activateserviceaccount.NewCmd(p))
+	cmd.AddCommand(getaccesstoken.NewCmd(p))
 }

internal/cmd/auth/get-access-token/get_access_token.go

@@ -0,0 +1,50 @@
+package getaccesstoken
+
+import (
+	"github.com/spf13/cobra"
+	"github.com/stackitcloud/stackit-cli/internal/pkg/args"
+	"github.com/stackitcloud/stackit-cli/internal/pkg/auth"
+	cliErr "github.com/stackitcloud/stackit-cli/internal/pkg/errors"
+	"github.com/stackitcloud/stackit-cli/internal/pkg/examples"
+	"github.com/stackitcloud/stackit-cli/internal/pkg/print"
+)
+
+func NewCmd(p *print.Printer) *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "get-access-token",
+		Short: "Prints a short-lived access token.",
+		Long:  "Prints a short-lived access token which can be used e.g. for API calls.",
+		Args:  args.NoArgs,
+		Example: examples.Build(
+			examples.NewExample(
+				`Print a short-lived access token`,
+				"$ stackit auth get-access-token"),
+		),
+		RunE: func(_ *cobra.Command, _ []string) error {
+			userSessionExpired, err := auth.UserSessionExpired()
+			if err != nil {
+				return err
+			}
+			if userSessionExpired {
+				return &cliErr.SessionExpiredError{}
+			}
+
+			accessToken, err := auth.GetAccessToken()
+			if err != nil {
+				return err
+			}
+
+			accessTokenExpired, err := auth.TokenExpired(accessToken)
+			if err != nil {
+				return err
+			}
+			if accessTokenExpired {
+				return &cliErr.AccessTokenExpiredError{}
+			}
+
+			p.Info("%s\n", accessToken)
+			return nil
+		},
+	}
+	return cmd
+}

internal/pkg/auth/auth.go

@@ -31,7 +31,7 @@ func AuthenticationConfig(p *print.Printer, reauthorizeUserRoutine func(p *print
 		return nil, fmt.Errorf("authentication flow not set")
 	}
 
-	userSessionExpired, err := userSessionExpired()
+	userSessionExpired, err := UserSessionExpired()
 	if err != nil {
 		return nil, fmt.Errorf("check if user session expired: %w", err)
 	}
@@ -42,7 +42,7 @@ func AuthenticationConfig(p *print.Printer, reauthorizeUserRoutine func(p *print
 		if userSessionExpired {
 			return nil, fmt.Errorf("session expired")
 		}
-		accessToken, err := getAccessToken()
+		accessToken, err := GetAccessToken()
 		if err != nil {
 			return nil, fmt.Errorf("get service account access token: %w", err)
 		}
@@ -73,7 +73,7 @@ func AuthenticationConfig(p *print.Printer, reauthorizeUserRoutine func(p *print
 	return authCfgOption, nil
 }
 
-func userSessionExpired() (bool, error) {
+func UserSessionExpired() (bool, error) {
 	sessionExpiresAtString, err := GetAuthField(SESSION_EXPIRES_AT_UNIX)
 	if err != nil {
 		return false, fmt.Errorf("get %s: %w", SESSION_EXPIRES_AT_UNIX, err)
@@ -87,7 +87,7 @@ func userSessionExpired() (bool, error) {
 	return now.After(sessionExpiresAt), nil
 }
 
-func getAccessToken() (string, error) {
+func GetAccessToken() (string, error) {
 	accessToken, err := GetAuthField(ACCESS_TOKEN)
 	if err != nil {
 		return "", fmt.Errorf("get %s: %w", ACCESS_TOKEN, err)

internal/pkg/auth/user_token_flow.go

@@ -44,7 +44,7 @@ func (utf *userTokenFlow) RoundTrip(req *http.Request) (*http.Response, error) {
 	}
 
 	accessTokenValid := false
-	accessTokenExpired, err := tokenExpired(utf.accessToken)
+	accessTokenExpired, err := TokenExpired(utf.accessToken)
 	if err != nil {
 		return nil, fmt.Errorf("check if access token has expired: %w", err)
 	} else if !accessTokenExpired {
@@ -108,7 +108,7 @@ func reauthenticateUser(utf *userTokenFlow) error {
 	return nil
 }
 
-func tokenExpired(token string) (bool, error) {
+func TokenExpired(token string) (bool, error) {
 	// We can safely use ParseUnverified because we are not authenticating the user at this point.
 	// We're just checking the expiration time
 	tokenParsed, _, err := jwt.NewParser().ParseUnverified(token, &jwt.RegisteredClaims{})

internal/pkg/errors/errors.go

@@ -32,6 +32,22 @@ You can authenticate as a user by running:
 or use a service account by running:
   $ stackit auth activate-service-account`
 
+	SESSION_EXPIRED = `Session is expired. Please log in again first.
+	
+You can authenticate as a user by running:
+$ stackit auth login
+
+or use a service account by running:
+$ stackit auth activate-service-account`
+
+	ACCESS_TOKEN_EXPIRED = `Access token is expired. Please log in again first.
+	
+You can authenticate as a user by running:
+$ stackit auth login
+
+or use a service account by running:
+$ stackit auth activate-service-account`
+
 	FAILED_SERVICE_ACCOUNT_ACTIVATION = `could not setup authentication based on the provided service account credentials. 
 Please double check if they are correctly configured.
 
@@ -230,6 +246,18 @@ func (e *AuthError) Error() string {
 	return FAILED_AUTH
 }
 
+type SessionExpiredError struct{}
+
+func (e *SessionExpiredError) Error() string {
+	return SESSION_EXPIRED
+}
+
+type AccessTokenExpiredError struct{}
+
+func (e *AccessTokenExpiredError) Error() string {
+	return ACCESS_TOKEN_EXPIRED
+}
+
 type ActivateServiceAccountError struct{}
 
 func (e *ActivateServiceAccountError) Error() string {