diff --git a/AGENTS.md b/AGENTS.md index d791e9d..0993c65 100644 --- a/AGENTS.md +++ b/AGENTS.md @@ -307,6 +307,14 @@ Grouped by what each one constrains. shutdown emits `close`. A retry that opens a socket and then loses it clears `closed` through `attach()`, which is why a second drop emits again. +- **An answer belongs to the link the message arrived on; a receipt does not.** Maintainer's call, + 2026-09-01: `sendResp()` carries the peer's own sequence number, which the next link knows nothing + about, so on a message whose link went it writes nothing and returns an `err`. Writing it to the + new socket instead succeeds and reports `{}` for a response that correlates with nothing, which is + goal 2's wrong answer. `sendDlr()` still goes out, because a receipt is a request of its own + correlated by `receipted_message_id`; the accepted cost is that one sent after a refused response + names an id the peer has no record of. + - **`reconnect` takes `{ minDelay, maxDelay }` to retune and `false` to turn off**, so absent means on and there is one spelling for each. Only `client()` reconnects — a `server()` session is a connection the peer opened, and nothing at this end can reopen it. The retry timer is `unref()`'d, diff --git a/README.md b/README.md index cb67bf3..7e48f98 100644 --- a/README.md +++ b/README.md @@ -398,7 +398,7 @@ The spec tables are exported both individually (`cmds`, `consts`, `encodings`, ` - **`server()` resolves once, when it is listening**, and gives you a handle with `close()`, `port` and a `session` event. It no longer calls your callback once per incoming connection. - **The id a message is answered with goes to `sendResp({ smsId })`**, and `sms.smsId` is read-only: - it reports what the response actually carried. Delete any `sms.smsId = …` line — assigning to it + it reports the id `sendResp()` was given, or the UUID v7 generated instead. Delete any `sms.smsId = …` line — assigning to it throws a `TypeError`, since modules are always strict mode — and pass the id to `sendResp()`. - **`checkuserpass` is now `authenticate`**, takes `{ password, session, systemId, systemType }` and returns `false` or `{ userData }`. diff --git a/src/dlr-merger.ts b/src/dlr-merger.ts index 678ad10..71d30a6 100644 --- a/src/dlr-merger.ts +++ b/src/dlr-merger.ts @@ -120,8 +120,8 @@ export class DlrMerger { } clear(): void { - this.groups.takeAll(); - this.spent.takeAll(); + this.groups.clear(); + this.spent.clear(); } /** Drops every group past its deadline. Runs before each collect and on its own timer. */ diff --git a/src/expiring-groups.ts b/src/expiring-groups.ts index 3a25d89..584a1a2 100644 --- a/src/expiring-groups.ts +++ b/src/expiring-groups.ts @@ -58,14 +58,9 @@ export class ExpiringGroups { this.idle(); } - /** Removes every group and hands them over. */ - takeAll(): [string, T][] { - const taken: [string, T][] = [...this.entries].map(([key, entry]) => [key, entry.group]); - + clear(): void { this.entries.clear(); this.idle(); - - return taken; } /** Removes every group past its deadline and hands them over. */ diff --git a/src/held-messages.ts b/src/held-messages.ts index 3324784..0a2a665 100644 --- a/src/held-messages.ts +++ b/src/held-messages.ts @@ -20,7 +20,6 @@ function keyOf(pduObjs: PduObject[]): string | undefined { /** The messages handed to the application that it has not answered yet, held by their segments. */ export class HeldMessages { - private readonly droppedWithLink = new WeakSet(); private readonly held: ExpiringGroups; private readonly idleWaiters = new IdleWaiters(); private readonly log: SmppLog; @@ -65,11 +64,6 @@ export class HeldMessages { return key !== undefined && this.held.get(key) === pduObjs; } - /** Whether this message's link went before it was answered, so no answer of ours correlates. */ - lostLink(pduObjs: PduObject[]): boolean { - return this.droppedWithLink.has(pduObjs); - } - release(pduObjs: PduObject[]): void { const key = keyOf(pduObjs); @@ -82,10 +76,7 @@ export class HeldMessages { /** Drops every message: their segments went with the link, so no answer of ours correlates now. */ clear(): void { - for (const [, pduObjs] of this.held.takeAll()) { - this.droppedWithLink.add(pduObjs); - } - + this.held.clear(); this.idleWaiters.settle(); } diff --git a/src/incoming-requests.ts b/src/incoming-requests.ts index 0487401..748dc14 100644 --- a/src/incoming-requests.ts +++ b/src/incoming-requests.ts @@ -39,6 +39,8 @@ export class IncomingRequests { private readonly session: Session; private readonly smsIdFormat: SmsIdFormat; private readonly systemId: string; + /** Bumped when a link goes, so a message from an earlier one knows its answer cannot correlate. */ + private linkGeneration = 0; constructor(options: IncomingRequestsOptions) { this.dlrMerger = options.dlrMerger; @@ -96,6 +98,7 @@ export class IncomingRequests { /** Drops the segments of every message that never became whole, and of every one still held. */ clear(): void { + this.linkGeneration++; this.held.clear(); this.reassembler.clear(); } @@ -163,6 +166,8 @@ export class IncomingRequests { if (!first) return; + const generation = this.linkGeneration; + const sms = createSms({ from: paramText(first.params.source_addr), message: decodeSegments(pduObjs), @@ -170,7 +175,7 @@ export class IncomingRequests { session: this.session, to: paramText(first.params.destination_addr), }, { - lostLink: () => this.held.lostLink(pduObjs), + lostLink: () => this.linkGeneration !== generation, // A turn later, so a listener sending its receipt straight after the response still holds. onAnswered: () => { setImmediate(() => { this.held.release(pduObjs); }); }, // Past the refusal only while a drain is still waiting for this message; an ordinary send after. diff --git a/src/reassembly.ts b/src/reassembly.ts index 59b1634..efc5e2e 100644 --- a/src/reassembly.ts +++ b/src/reassembly.ts @@ -163,7 +163,7 @@ export class Reassembler { } clear(): void { - this.groups.takeAll(); + this.groups.clear(); this.octets = 0; } diff --git a/src/sms.ts b/src/sms.ts index 8f8f847..7a679be 100644 --- a/src/sms.ts +++ b/src/sms.ts @@ -54,7 +54,6 @@ export type SmsInput = { /** What the session's incoming side gives a message so it can be answered and accounted for. */ export type SmsHandlers = { - /** Whether the link this message arrived on is gone, so no answer of ours correlates. */ lostLink: () => boolean; onAnswered: () => void; send: (input: PduObjectInput) => Promise>; @@ -107,13 +106,13 @@ async function sendResp( return { err: new Error('smsId must not be empty') }; } + if (options.smsId !== undefined) answered.smsId = options.smsId; + // A response carries the sequence number it was asked on, which the next link knows nothing about. if (lostLink()) { return { err: new Error('The link this message arrived on is gone, so nothing would correlate the response') }; } - if (options.smsId !== undefined) answered.smsId = options.smsId; - const results = await Promise.all(sms.pduObjs.map((pduObj, index) => sms.session.sendReturn( pduObj, options.status ?? 'ESME_ROK', diff --git a/test/session-extras.test.ts b/test/session-extras.test.ts index 087deec..c8b17a7 100644 --- a/test/session-extras.test.ts +++ b/test/session-extras.test.ts @@ -557,38 +557,56 @@ describe('reconnect', () => { assert.equal(report.segments.length, 3); }); - test('refuses to answer a message whose link went, rather than reporting it delivered', async t => { + test('refuses to answer a message whose link went, held or already answered', async t => { const smpp = await startServer(t); const { session } = await connect(t, smpp, { reconnect: { maxDelay: 100, minDelay: 20 } }); assert.ok(session); - const arrived = once(resolve => { session.on('sms', resolve); }); + const arrived: Sms[] = []; + const both = once(resolve => { + session.on('sms', sms => { + arrived.push(sms); - void peerOf(smpp).send({ - cmdName: 'deliver_sm', - params: { - destination_addr: '46701113311', - short_message: 'answered too late', - source_addr: '46709771337', - }, + if (arrived.length === 2) resolve(true); + }); }); - const sms = await arrived; + for (const text of ['answered before the drop', 'never answered']) { + void peerOf(smpp).send({ + cmdName: 'deliver_sm', + params: { + destination_addr: '46701113311', + short_message: text, + source_addr: '46709771337', + }, + }); + } + + await both; + + const [answered, held] = arrived; + + assert.ok(answered); + assert.ok(held); + assert.equal((await answered.sendResp()).err, undefined); + const reconnected = once(resolve => { session.on('reconnected', () => { resolve(true); }); }); await peerOf(smpp).close({ signal: AbortSignal.abort() }); await reconnected; - const answered = await sms.sendResp(); + const taken: string[] = []; - assert.match(answered.err?.message ?? '', /link this message arrived on is gone/); + peerOf(smpp).on('incomingPduObj', pduObj => { taken.push(pduObj.cmdName); }); + + // The answered one is out of the hold and the held one is not, so neither may reach the answer. + assert.match((await answered.sendResp()).err?.message ?? '', /link this message arrived on is gone/); + assert.match((await held.sendResp()).err?.message ?? '', /link this message arrived on is gone/); // A receipt is a request of its own, correlated by its id, so the new link carries it. - const report = await sms.sendDlr('DELIVERED'); - - assert.equal(report.err, undefined); - assert.equal(report.pduObjs.length, 1); + assert.equal((await held.sendDlr('DELIVERED')).err, undefined); + assert.deepEqual(taken, ['deliver_sm'], 'a response reached the new link'); }); test('does not reconnect after an explicit close', async t => { @@ -947,20 +965,6 @@ describe('held message bounds', () => { held.clear(); }); - test('remembers which messages went with the link, and which were answered', () => { - const held = new HeldMessages({ log: silentLog, max: 10, timeout: 10_000 }); - const answered = message(1); - const dropped = message(2); - - held.hold(answered); - held.hold(dropped); - held.release(answered); - held.clear(); - - assert.equal(held.lostLink(dropped), true); - assert.equal(held.lostLink(answered), false); - }); - // Without this the drain sits out its whole budget before returning what a sweep already settled. test('wakes a waiting drain when the last message expires', async () => { let now = 0; diff --git a/todo.md b/todo.md index b495093..e965f55 100644 --- a/todo.md +++ b/todo.md @@ -141,6 +141,11 @@ session message is a change to every call site. until the message expires. Same cost as the `onRequest`-answers-nothing case that was declined, but reached by a bug rather than a policy. Raised by review, 2026-09-01. +- [ ] **A refused `sendResp()` releases the hold anyway.** Every early return runs + `.finally(onAnswered)`, so `sendResp({ smsId: '' })` refuses and stops the drain waiting for a + message the peer was never answered, which `close()` then reports as answered. Raised by + review, 2026-09-01. + - [ ] **Does an intermediate delivery notification deserve to be a `dlr`?** `esm_class` message type `INTERMEDIATE_DELIVERY` (0x20) is classified as a message today, so a peer that reports non-final states with it hands the application a raw `id:… stat:ENROUTE` text as an inbound