Function assertImageConsumersValid

showcase/scripts/railway-envs.ts:2319–2388

(
  services: Record<
    string,
    {
      ciBuilt: boolean;
      imageOf?: string;
      environments?: Record<string, unknown>;
    }
  > = SERVICES,
)

 * Accepts an injected map for testing; defaults to the real SERVICES map.
 */
export function assertImageConsumersValid(
  services: Record<
    string,
    {
      ciBuilt: boolean;
      imageOf?: string;
      environments?: Record<string, unknown>;
    }
  > = SERVICES,
): void {
  const problems: string[] = [];
  for (const [key, entry] of Object.entries(services)) {
    const target = entry.imageOf;
    if (target === undefined) continue;
    if (entry.ciBuilt) {
      problems.push(
        `  - "${key}" is ciBuilt but declares imageOf "${target}" — a build slot is its own image producer; drop one of the two`,
      );
      continue;
    }
    // Own-property lookup: a bare `services[target]` truthiness check
    // would resolve inherited Object.prototype keys (e.g. imageOf:
    // "toString") to a truthy non-entry and misreport the dangling target.
    if (!Object.hasOwn(services, target)) {
      problems.push(
        `  - imageOf "${target}" on "${key}" is not an SSOT key in SERVICES`,
      );
      continue;
    }
    const targetEntry = services[target];
    if (!targetEntry.ciBuilt) {
      problems.push(
        `  - imageOf "${target}" on "${key}" points at a service that is not ciBuilt — only showcase_build.yml build slots can have image consumers`,
      );
      continue;
    }
    // A consumer with ZERO declared environments passes the env-subset
    // check below vacuously — but a consumer that exists in no env is a
    // service the redeploy expansion can never reach (expandImageConsumers
    // filters on `environments[env]`), i.e. a silently never-redeployed
    // service. Reject it loudly.
    const consumerEnvs = Object.keys(entry.environments ?? {});
    if (consumerEnvs.length === 0) {
      problems.push(
        `  - "${key}" declares imageOf "${target}" but ZERO environments — the env-subset check passes vacuously and the consumer would never be redeployed in any env`,
      );
      continue;
    }
    // Env overlap: every env the consumer declares must also be one the
    // producer builds for. A consumer-only env would run an image that no
    // CI build ever refreshes there — a silently never-updating service,
    // the exact stale-image failure this invariant exists to prevent.
    const producerEnvs = targetEntry.environments ?? {};
    for (const env of consumerEnvs) {
      if (!Object.hasOwn(producerEnvs, env)) {
        problems.push(
          `  - "${key}" declares env "${env}" but its imageOf "${target}" has no "${env}" environment — "${key}" would run a never-rebuilt image there`,
        );