| 1 | import { noGrant } from "./errors.js"; |
| 2 | |
| 3 | export interface BrowserGrant { |
| 4 | grantId: string; |
| 5 | taskId: string; |
| 6 | sessionId: string; |
| 7 | generation: string; |
| 8 | createdAt: number; |
| 9 | } |
| 10 | |
| 11 | export interface GrantRegistryDeps { |
| 12 | generation(): string; |
| 13 | now?(): number; |
| 14 | onRevoked?(grant: BrowserGrant): void; |
| 15 | } |
| 16 | |
| 17 | // Grants are minted by Go per task (its "tabId") and die with the service |
| 18 | // generation that minted them, so a restarted service can never act on a |
| 19 | // grant it does not remember. |
| 20 | export class GrantRegistry { |
| 21 | private readonly grants = new Map<string, BrowserGrant>(); |
| 22 | private generation = ""; |
| 23 | |
| 24 | constructor(private readonly deps: GrantRegistryDeps) {} |
| 25 | |
| 26 | install(input: { grantId: string; taskId: string; sessionId: string }): BrowserGrant { |
| 27 | if (input.grantId === "" || input.taskId === "") throw noGrant("grantId and tabId are required"); |
| 28 | const generation = this.deps.generation(); |
| 29 | if (generation === "") throw noGrant("desktop service is not running"); |
| 30 | this.generation = generation; |
| 31 | const grant: BrowserGrant = { ...input, generation, createdAt: (this.deps.now ?? Date.now)() }; |
| 32 | this.grants.set(input.grantId, grant); |
| 33 | return grant; |
| 34 | } |
| 35 | |
| 36 | revoke(grantId: string): BrowserGrant | null { |
| 37 | const grant = this.grants.get(grantId); |
| 38 | if (!grant) return null; |
| 39 | this.grants.delete(grantId); |
| 40 | this.deps.onRevoked?.(grant); |
| 41 | return grant; |
| 42 | } |
| 43 | |
| 44 | // A generation change (service restart) retires every grant at once. |
| 45 | observeGeneration(generation: string): void { |
| 46 | if (generation === this.generation) return; |
| 47 | this.generation = generation; |
| 48 | for (const grantId of [...this.grants.keys()]) this.revoke(grantId); |
| 49 | } |
| 50 | |
| 51 | verify(grantId: string): BrowserGrant { |
| 52 | const grant = this.grants.get(grantId); |
| 53 | if (!grant) throw noGrant(`unknown grant ${grantId || "(empty)"}`); |
| 54 | if (grant.generation !== this.deps.generation()) { |
| 55 | this.revoke(grantId); |
| 56 | throw noGrant("grant belongs to an earlier service generation"); |
| 57 | } |
| 58 | return grant; |
| 59 | } |
| 60 | |
| 61 | // The tab must belong to the grant's task; a grant never reaches across. |
| 62 | verifyTab(grantId: string, tabTaskId: string | undefined): BrowserGrant { |
| 63 | const grant = this.verify(grantId); |
| 64 | if (tabTaskId === undefined) throw noGrant("unknown browser tab"); |
| 65 | if (tabTaskId !== grant.taskId) throw noGrant("browser tab belongs to another task"); |
| 66 | return grant; |
| 67 | } |
| 68 | |
| 69 | get size(): number { |
| 70 | return this.grants.size; |
| 71 | } |
| 72 | } |
| 73 |