Function readUrl

showcase/shell-docs/src/lib/runtime-config.ts:165–198

(
  envKey: string,
  fallback: string,
  isProd: boolean,
  severity: "fatal" | "info" = "fatal",
)

}

function readUrl(
  envKey: string,
  fallback: string,
  isProd: boolean,
  severity: "fatal" | "info" = "fatal",
): string {
  const value = readEnvPair(envKey);
  if (value !== undefined) return value.replace(/\/+$/, "");
  if (isProd) {
    if (severity === "fatal") {
      // eslint-disable-next-line no-console
      console.error(
        `[shell-docs runtime-config] FATAL-CONFIG: ${envKey} is unset in a production deploy; ` +
          `using fallback ${fallback}. Set the env var on the Railway service.`,
      );
    } else {
      // warn-level: legitimate prod default exists; absence is
      // recoverable so we log but do not raise the FATAL-CONFIG flag
      // that triggers ops alerts. console.warn (not console.info) so
      // the line clears prod log-aggregation thresholds and stays
      // visible to operators.
      // eslint-disable-next-line no-console
      console.warn(
        `[shell-docs runtime-config] ${envKey} unset; using prod default ${fallback}`,
      );
    }
  } else {
    // eslint-disable-next-line no-console
    console.warn(
      `[shell-docs runtime-config] ${envKey} unset; using dev fallback ${fallback}`,
    );
  }
  return fallback.replace(/\/+$/, "");
}

/**
 * Read an analytics key. Empty/missing values are returned as the empty