gotify/server · error

invalid JSON for %s: %w

Error message

invalid JSON for %s: %w

What it means

parseMap unmarshals a JSON-encoded environment/config value into a map[string]string. When json.Unmarshal fails because the raw string is not a valid JSON object with string values, it wraps the underlying error with the environment variable name for context.

Source

Thrown at config/parse.go:103

	record, err := reader.Read()
	if err != nil {
		return fmt.Errorf("invalid CSV for %s (%q): %w", env, raw, err)
	}
	*target = record
	return nil
}

func parseMap(target *map[string]string, env string) error {
	raw, ok, err := lookupEnv(env)
	if err != nil {
		return err
	}
	if !ok || raw == "" {
		return nil
	}
	out := map[string]string{}
	if err := json.Unmarshal([]byte(raw), &out); err != nil {
		return fmt.Errorf("invalid JSON for %s: %w", env, err)
	}
	*target = out
	return nil
}

func parseLogLevel(target *LogLevel, env string) error {
	raw, ok, err := lookupEnv(env)
	if err != nil {
		return err
	}
	if !ok {
		return nil
	}
	return target.Decode(raw)
}

View on GitHub (pinned to 14bfc25627)

Solutions

1. Fix the env var value to be a valid JSON object with only string values, e.g. {"key":"value"}
2. Validate the JSON locally (e.g. echo '<value>' | jq .) before deploying
3. If the value is meant to be a plain string, use the appropriate non-map accessor instead of the map parser

Example fix

// before
MY_MAP={'a':'b'}
// after
MY_MAP={"a":"b"}

raw := os.Getenv("MY_MAP")
if raw != "" {
    var probe map[string]string
    if err := json.Unmarshal([]byte(raw), &probe); err != nil {
        return fmt.Errorf("MY_MAP is not valid JSON: %w", err)
    }
}

m, err := cfg.Get("MY_MAP")
if err != nil {
    var je *json.SyntaxError
    if errors.As(err, &je) {
        log.Fatalf("fix MY_MAP JSON near offset %d", je.Offset)
    }
    return err
}

When it happens

Trigger: Get is called for a config key whose raw env value is non-empty but is not a valid JSON object, e.g. a value missing quotes around keys, using single quotes, trailing commas, or containing non-string values.

Common situations: Developers set env vars like FOO_MAP={"a":1} (integer value) or FOO_MAP={'a':'b'} (single quotes from shell habits) instead of strictly valid JSON with string values: {"a":"b"}.

Understand the failure class

• Parsing and encoding errors: unexpected token, malformed input — why parsers reject input and how to find the real culprit.

Related errors

• username claim was empty
• unknown log level
• migrate-config requires one argument: the path to the old co
• read file for %s_FILE (%s): %w
• invalid int for %s (%q): %w

AI-assisted analysis of gotify/server@14bfc25627 (2026-09-05). Data as JSON: /api/errors/1a576fcf04000732. Report an issue: GitHub.