chore: add command to easily visualize different errors

coder · Emyrk · Sep 29, 2023 · Sep 29, 2023 · Sep 29, 2023 · Sep 29, 2023
commit f2cbe7760970e2da0827eac0ac82110f1fe72441
diff --git a/cli/errors.go b/cli/errors.go
@@ -0,0 +1,83 @@
+package cli
+
+import (
+	"io"
+	"os"
+
+	"github.com/coder/coder/v2/cli/clibase"
+	"github.com/coder/coder/v2/codersdk"
+	"golang.org/x/xerrors"
+)
+
+func (r *RootCmd) errorExample() *clibase.Cmd {
+	errorCmd := func(use string, err error) *clibase.Cmd {
+		return &clibase.Cmd{
+			Use: use,
+			Handler: func(inv *clibase.Invocation) error {
+				return err
+			},
+		}
+	}
+
+	cmd := &clibase.Cmd{
+		Use:   "example-error",
+		Short: "Shows what different error messages look like",
+		Long: "This command is pretty pointless, but without it testing errors is" +
+			"difficult to visually inspect. Error message formatting is inherently" +
+			"visual, so we need a way to quickly see what they look like.",
+		Handler: func(inv *clibase.Invocation) error {
+			return inv.Command.HelpHandler(inv)
+		},
+		Children: []*clibase.Cmd{
+			// Typical codersdk error
+			errorCmd("sdk", &codersdk.Error{
+				Response: codersdk.Response{
+					Message: "Top level sdk error message.",
+					Detail:  "magic dust unavailable, please try again later",
+					Validations: []codersdk.ValidationError{
+						{
+							Field:  "region",
+							Detail: "magic dust is not available in your region",
+						},
+					},
+				},
+				Helper: "Have you tried turning it off and on again?",
+			}),
+
+			// Typical cli error
+			errorCmd("cmd", xerrors.Errorf("some error: %w", errorWithStackTrace())),
+
+			// A multi-error
+			{
+				Use: "multi-error",
+				Handler: func(inv *clibase.Invocation) error {
+					// Closing the stdin file descriptor will cause the next close
+					// to fail. This is joined to the returned Command error.
+					if f, ok := inv.Stdin.(*os.File); ok {
+						_ = f.Close()
+					}
+
+					return xerrors.Errorf("some error: %w", errorWithStackTrace())
+				},
+			},
+		},
+	}
+
+	return cmd
+}
+
+type errorClose struct {
+	io.ReadCloser
+}
+
+func (e errorClose) Close() error {
+	err := e.ReadCloser.Close()
+	if err == nil {
+		return xerrors.Errorf("always close error")
+	}
+	return err
+}
+
+func errorWithStackTrace() error {
+	return xerrors.Errorf("function decided not to work, and it never will")
+}
diff --git a/cli/exp.go b/cli/exp.go
@@ -12,6 +12,7 @@ func (r *RootCmd) expCmd() *clibase.Cmd {
 		Hidden: true,
 		Children: []*clibase.Cmd{
 			r.scaletestCmd(),
+			r.errorExample(),
 		},
 	}
 	return cmd