go-kratos/kratos · warning

%s already exists

Error message

%s already exists

What it means

proto.Add (used by kratos proto add / new for API templates) is create-only: it creates the target directory if missing, then refuses to overwrite an existing file with the same name. The error names the file that already exists under the target path.

Source

Thrown at cmd/kratos/internal/proto/add/proto.go:37

// Generate generate a proto template.
func (p *Proto) Generate() error {
	body, err := p.execute()
	if err != nil {
		return err
	}
	wd, err := os.Getwd()
	if err != nil {
		panic(err)
	}
	to := filepath.Join(wd, p.Path)
	if _, err := os.Stat(to); os.IsNotExist(err) {
		if err := os.MkdirAll(to, 0o700); err != nil {
			return err
		}
	}
	name := filepath.Join(to, p.Name)
	if _, err := os.Stat(name); !os.IsNotExist(err) {
		return fmt.Errorf("%s already exists", p.Name)
	}
	return os.WriteFile(name, body, 0o644)
}

View on GitHub (pinned to 668db92c2c)

Solutions

1. Delete or rename the existing file, then re-run the command
2. Choose a different proto file/service name for the new API
3. If regenerating on purpose, script the delete step first — the tool never overwrites

Example fix

# before
$ kratos proto add user/v1/user.proto
# ERROR: user.proto already exists

# after
$ rm api/user/v1/user.proto
$ kratos proto add user/v1/user.proto

target := filepath.Join(wd, p.Path, p.Name)
if _, err := os.Stat(target); err == nil {
    return fmt.Errorf("skip %s: already exists", p.Name)
}
// proceed with proto add

When it happens

Trigger: Calling the proto add path twice, or scaffolding an API file whose final path os.Stat finds already existing (p.Path/p.Name combination present on disk).

Common situations: Re-running generation after a partial failure; two services sharing the same proto file name; leftover files from a previous layout attempt.

Related errors

• 🚫 failed to get relative path: %v
• unable to parse repo url
• invalid formatting for map key
• no field path
• no value provided

AI-assisted analysis of go-kratos/kratos@668db92c2c (2026-08-16). Data as JSON: /api/errors/18f841ce8219a36b. Report an issue: GitHub.