grpc-ecosystem/grpc-gateway · error

segment neither wildcards, literal or variable: %w

Error message

segment neither wildcards, literal or variable: %w

What it means

Fallback error from parser.segment: a path-template segment matched none of '*', '**', literal, or variable (variable() itself failed). The wrapped error describes the underlying cause; the faulting input is the offending segment in the google.api.http path template.

Source

Thrown at internal/httprule/parse.go:168

		}
		segs = append(segs, s)
	}
}

func (p *parser) segment() (segment, error) {
	if _, err := p.accept("*"); err == nil {
		return wildcard{}, nil
	}
	if _, err := p.accept("**"); err == nil {
		return deepWildcard{}, nil
	}
	if l, err := p.literal(); err == nil {
		return l, nil
	}

	v, err := p.variable()
	if err != nil {
		return nil, fmt.Errorf("segment neither wildcards, literal or variable: %w", err)
	}
	return v, nil
}

func (p *parser) literal() (segment, error) {
	lit, err := p.accept(typeLiteral)
	if err != nil {
		return nil, err
	}
	return literal(lit), nil
}

func (p *parser) variable() (segment, error) {
	if _, err := p.accept("{"); err != nil {
		return nil, err
	}

	path, err := p.fieldPath()

View on GitHub (pinned to a58a4436a3)

Solutions

1. Rewrite the offending segment as a literal, '*'/'**' wildcard, or '{var}' variable per http.proto syntax.
2. Inspect the wrapped cause (e.g. invalid identifier or missing brace) for the exact character problem.

When it happens

Trigger: Thrown at internal/httprule/parse.go:168 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of grpc-ecosystem/grpc-gateway@a58a4436a3 (2026-09-02). Data as JSON: /api/errors/3f5854a662aabd22. Report an issue: GitHub.