caddyserver/caddy · error

loading upstream source modules: %v

Error message

loading upstream source modules: %v

What it means

Error "loading upstream source modules: %v" thrown in caddyserver/caddy.

Source

Thrown at modules/caddyhttp/reverseproxy/upstreams.go:483

	logger *zap.Logger
}

// CaddyModule returns the Caddy module information.
func (MultiUpstreams) CaddyModule() caddy.ModuleInfo {
	return caddy.ModuleInfo{
		ID:  "http.reverse_proxy.upstreams.multi",
		New: func() caddy.Module { return new(MultiUpstreams) },
	}
}

func (mu *MultiUpstreams) Provision(ctx caddy.Context) error {
	mu.logger = ctx.Logger()

	if mu.SourcesRaw != nil {
		mod, err := ctx.LoadModule(mu, "SourcesRaw")
		if err != nil {
			return fmt.Errorf("loading upstream source modules: %v", err)
		}
		sources := mod.([]any)
		mu.sources = make([]UpstreamSource, 0, len(sources))
		for _, src := range sources {
			mu.sources = append(mu.sources, src.(UpstreamSource))
		}
	}

	return nil
}

func (mu MultiUpstreams) GetUpstreams(r *http.Request) ([]*Upstream, error) {
	var upstreams []*Upstream

	for i, src := range mu.sources {
		select {
		case <-r.Context().Done():
			return upstreams, context.Canceled

View on GitHub (pinned to 50e54ee279)

Solutions

1. Check the wrapped error for the failing upstream source module and fix its configuration or module name.

When it happens

Trigger: Thrown at modules/caddyhttp/reverseproxy/upstreams.go:483 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of caddyserver/caddy@50e54ee279 (2026-08-15). Data as JSON: /api/errors/91878cc55412f95b. Report an issue: GitHub.