src/health-format.ts

Functions

Imports

It imports no other module of this repo. Imported by src/ops-snapshot.ts.

Source

1// THE HEALTH FORMAT every site answers on its health route (docs/health-format.md).
2// Capsid defines it so the watcher's sha rule can read every site the same way.
3
4export const HEALTH_STATUSES = ["ok", "degraded", "down"] as const;
5type HealthStatus = (typeof HEALTH_STATUSES)[number];
6
7export interface ParsedHealth {
8  // Null when the body does not carry one of the three statuses.
9  status: HealthStatus | null;
10  // The deployed commit, or null when the body reports none.
11  sha: string | null;
12}
13
14const MAX_SHA_CHARS = 40;
15
16/** What a health body says in the standard format. Anything that is not JSON, or a field
17 *  that is not the right type, reads as absent: a site that does not report a sha is a
18 *  finding for the sha rule, never a crash in the probe. Extra fields are ignored. */
19export function parseHealth(body: string | null): ParsedHealth {
20  const none: ParsedHealth = { status: null, sha: null };
21  if (!body) return none;
22  let parsed: unknown;
23  try {
24    parsed = JSON.parse(body);
25  } catch {
26    return none;
27  }
28  if (parsed === null || typeof parsed !== "object") return none;
29  const { status, sha } = parsed as { status?: unknown; sha?: unknown };
30  return {
31    status: typeof status === "string" && (HEALTH_STATUSES as readonly string[]).includes(status) ? (status as HealthStatus) : null,
32    sha: typeof sha === "string" && sha.length > 0 ? sha.slice(0, MAX_SHA_CHARS) : null,
33  };
34}