go-kratos/kratos · critical

invalid Discovery config nodes:%+v region:%s zone:%s deployE

Error message

invalid Discovery config nodes:%+v region:%s zone:%s deployEnv:%s host:%s

What it means

fixConfig validates the Discovery client Config at construction: Nodes, Region, Zone, and Env must be non-empty, and Host defaults to os.Hostname(); any gap aborts with this error listing the offending values. It prevents starting a client that could never resolve or register correctly.

Source

Thrown at contrib/registry/discovery/discovery_helper.go:54

	_statusUP       = "1"
	_discoveryAppID = "infra.discovery"
)

// Config Discovery configures.
type Config struct {
	Nodes  []string
	Region string
	Zone   string
	Env    string
	Host   string
}

func fixConfig(c *Config) error {
	if c.Host == "" {
		c.Host, _ = os.Hostname()
	}
	if len(c.Nodes) == 0 || c.Region == "" || c.Zone == "" || c.Env == "" || c.Host == "" {
		return fmt.Errorf(
			"invalid Discovery config nodes:%+v region:%s zone:%s deployEnv:%s host:%s",
			c.Nodes,
			c.Region,
			c.Zone,
			c.Env,
			c.Host,
		)
	}
	return nil
}

// discoveryInstance represents a server the client connects to.
type discoveryInstance struct {
	Region   string   `json:"region"`           // Region is region.
	Zone     string   `json:"zone"`             // Zone is IDC.
	Env      string   `json:"env"`              // Env prod/pre/uat/fat1
	AppID    string   `json:"appid"`            // AppID is mapping service-tree appId.
	Hostname string   `json:"hostname"`         // Hostname is hostname from docker

View on GitHub (pinned to 668db92c2c)

Solutions

1. Set every required field: Nodes plus Region, Zone, Env (and Host if the hostname cannot be resolved)
2. Wire the discovery config section from env vars so containers always populate it
3. Validate the config at startup and fail fast with a clear message

Example fix

// before
r := discovery.New(&discovery.Config{Nodes: []string{"127.0.0.1:7171"}})

// after
r := discovery.New(&discovery.Config{
    Nodes:  []string{"127.0.0.1:7171"},
    Region: "sh",
    Zone:   "sh001",
    Env:    "dev",
})

func validateDiscoveryConfig(c *discovery.Config) error {
    if c.Host == "" {
        c.Host, _ = os.Hostname()
    }
    if len(c.Nodes) == 0 || c.Region == "" || c.Zone == "" || c.Env == "" || c.Host == "" {
        return errors.New("discovery config needs Nodes, Region, Zone, Env, Host")
    }
    return nil
}

When it happens

Trigger: Constructing the discovery registry with a Config missing Nodes, Region, Zone, or Env — or with Host empty and os.Hostname() failing — so fixConfig's validation fails.

Common situations: Migrating configs that only set Nodes; missing REGION/ZONE/DEPLOY_ENV env vars in containers; scratch/distroless images where hostname lookup fails.

Related errors

• Discovery.GetService(%s) not found
• register failed: instance duplicated:
• config: merge src must be map[string]interface{}, got %T
• ErrorCode: %d
• unable to parse repo url

AI-assisted analysis of go-kratos/kratos@668db92c2c (2026-08-16). Data as JSON: /api/errors/dc07d6ed898d1a1c. Report an issue: GitHub.