@hasna/events

Shared event envelopes, local channels, replay, and delivery transports for Hasna open-source apps.

This package is local-first. By default it stores JSON files under ~/.hasna/events:

• channels.json
• events.json
• deliveries.json

The data home is resolved through the shared @hasna/paths resolver, in this order:

1. The CLI --dir flag (highest precedence);
2. the exact-app HASNA_EVENTS_DIR override, then the legacy HASNA_EVENTS_HOME fallback;
3. the @hasna/paths-resolved XDG data home (HASNA_DATA_HOME/~/.local/share/hasna/events), adopted once HASNA_DATA_HOME is set or the store has been physically migrated there (events.json exists at that home);
4. the legacy ~/.hasna/events default.

Nothing moves on its own: the package keeps reading and writing whichever home is effective, and the legacy ~/.hasna/events stays effective until an operator opts into the XDG layout or the store is migrated to it.

Storage Runtime Contract

The default compatibility runtime is local JSON files. It does not use local SQLite, remote Postgres, S3, AWS infrastructure, or live cloud mutation. Apps that require cross-process idempotency and restart-safe webhook delivery should use the opt-in durable spool and SQLite broker described below.

import { getEventsStatus } from "@hasna/events";

const status = await getEventsStatus();

console.log(status.storage);
// {
//   mode: "local-files",
//   localFiles: true,
//   localSqlite: false,
//   remote: false,
//   postgres: false,
//   s3: false,
//   aws: false,
//   idempotency: "best-effort-local",
//   replayCursors: true
// }

Cloud-backed stores should implement the same EventsStore interface and, for durable event-bus use, the optional appendEventOnce and listEventsPage methods. appendEventOnce is the storage-layer hook for atomic idempotency by id or dedupeKey, such as a Postgres unique constraint or equivalent provider guarantee. listEventsPage returns an opaque cursor page for bounded replay. The local JSON store implements these hooks for deterministic local tests, but its idempotency is best-effort local file behavior, not a cross-process database lock.

Remote Postgres/S3/AWS adapters should keep credentials and infrastructure provisioning outside this package configuration, report their storage mode in status.storage, and avoid emitting live external deliveries during store tests. Creating buckets, databases, secrets, migrations, or production data changes is an explicit deployment/approval step, not part of this local runtime.

Install

bun add @hasna/events

The core CLI and durable SQLite broker require Bun 1.0 or newer. The isolated @hasna/events/durable-spool producer export supports Node 20 or newer.

Event Envelope

All apps should emit the same stable envelope:

import { EventsClient } from "@hasna/events";

const events = new EventsClient();

await events.emit({
  id: "optional-stable-id",
  source: "tickets",
  type: "ticket.created",
  time: new Date(),
  subject: "ticket:123",
  severity: "notice",
  data: { ticketId: 123 },
  message: "Ticket created",
  dedupeKey: "tickets:ticket:123:created",
  schemaVersion: "1.0",
  metadata: { tenant: "acme" },
});

Only source and type are required inputs. id defaults to a UUID, time to the current ISO timestamp, severity to info, data and metadata to empty objects, and schemaVersion to 1.0. subject, message, and dedupeKey are optional.

source should be the emitting app or bounded context. type should use dot notation such as ticket.created, repo.synced, or check.failed. Emission deduplicates by either an explicit id or dedupeKey by default; a duplicate is neither stored nor delivered again. Library callers can pass { dedupe: false } to store a duplicate intentionally.

Package Entry Points

The root export includes the client, types, storage, filtering, signing, transports, and catalog APIs. Focused entry points are also available:

• @hasna/events/storage
• @hasna/events/signing
• @hasna/events/filter
• @hasna/events/transports
• @hasna/events/catalog
• @hasna/events/commander
• @hasna/events/cli

Typed Event Catalog (Distribution Events)

@hasna/events/catalog binds well-known envelope type strings to the @hasna/contracts schema ids their data payloads mirror, and provides an OPT-IN emit-time validator hook.

Distribution event types (DISTRIBUTION_EVENT_TYPES):

| Event type | Contracts schema (data mirror) | | --- | --- | | release.published | hasna.release.v1 | | release.rollout.started | hasna.rollout_record.v1 | | release.rollout.completed | hasna.rollout_record.v1 | | release.rollout.failed | hasna.rollout_record.v1 | | app.installed | hasna.rollout_record.v1 | | announcement.sent | hasna.announcement.v1 | | feedback.created | hasna.feedback.v1 | | feedback.triaged | hasna.feedback.v1 |

import { EventsClient, EventTypeCatalog, registerDistributionEventTypes } from "@hasna/events";

const catalog = registerDistributionEventTypes(new EventTypeCatalog());
const client = new EventsClient({ catalog, validateCatalogTypes: true });

// Registered type with an invalid payload throws EventValidationError
// BEFORE the event is stored or delivered.
await client.emit({
  source: "publish",
  type: "release.published",
  data: { appId: "todos" },
});

Validation is fully backward compatible:

• It is OFF by default (validateCatalogTypes defaults to false).
• Unregistered/free-form event types ALWAYS pass, even when validation is on.
• A per-emit validate option overrides the client setting in both directions.

Payload types (ReleasePublishedData, RolloutData, AppInstalledData, AnnouncementSentData, FeedbackCreatedData, FeedbackTriagedData) are dependency-free structural mirrors of the contracts schemas; this package does not depend on @hasna/contracts at runtime.

OpenAutomations Trigger Ingress

@hasna/events is trigger ingress for OpenAutomations. It records and delivers event envelopes, but it does not own durable automation runs, action queues, approvals, DLQ state, or replay decisions. @hasna/automations consumes the same envelope shape and materializes matching events into durable automation runs.

For automation-triggered events:

• set source to the emitting app or bounded context
• set type with dot notation, such as ticket.created
• set subject when the event describes one stable domain object
• set dedupeKey when the producer has a stable business identity
• keep id stable for the specific emitted envelope
• put only serializable trigger data in data
• keep secrets out of data and metadata; pass secret references instead

OpenAutomations derives idempotency from dedupeKey first and falls back to id when no dedupe key is present. Replaying events through events events replay re-delivers envelopes; OpenAutomations is still responsible for deciding whether that delivery creates a new run, returns the existing idempotent run, or creates an explicit replay request.

OpenLoops Task Notifications

@hasna/events is also notification ingress for OpenLoops task-created routes. It delivers todos envelopes to configured channels, but it does not import OpenLoops, create workflow invocations, own admission queue state, run agents, or decide worker retry/backpressure policy. OpenLoops is the consumer that handles an envelope, dedupes/upserts a work item, admits it when capacity is available, and records workflow run manifests under .hasna/loops/runs.

Replay remains delivery-only. Replaying a todos.task.created or task.created envelope sends the event to matching channels again; OpenLoops decides whether that replay is ignored as an already-admitted task, resumes existing work, or creates an explicit replay work item.

Channels And Filters

Channels are reusable notification routes. They can be enabled or disabled, filtered by source/type/subject/severity, and configured with transport-specific settings.

await events.addChannel({
  id: "ops-webhook",
  enabled: true,
  transport: "webhook",
  filters: [{ type: "ticket.*", severity: ["warning", "error", "critical"] }],
  webhook: {
    url: "https://example.com/channels/hasna",
    secret: process.env.HASNA_WEBHOOK_SECRET,
  },
  retry: {
    maxAttempts: 3,
    backoffMs: 500,
    multiplier: 2,
  },
  redact: {
    paths: ["data.token", "metadata.authorization"],
  },
});

All matchers inside one filter are ANDed. Multiple filters on a channel are ORed. A channel with no filters accepts every event, while a disabled channel accepts none. String matchers support * and **; data and metadata matchers also support nested or literal dotted keys, primitive array-member matching, typed values, and negative matchers.

Webhook Transport

Webhook delivery sends a POST with the event envelope as JSON.

Headers:

• Content-Type: application/json
• User-Agent: @hasna/events
• X-Hasna-Event-Id
• X-Hasna-Event-Type
• X-Hasna-Timestamp
• X-Hasna-Signature when webhook.secret or webhook.secretRef resolves

X-Hasna-Timestamp is the current delivery-attempt time and is what the HMAC signs. The envelope time in the JSON body remains the original event time, so delayed imports and retries receive fresh replay-window signatures without rewriting domain history. Custom webhook headers whose names begin with X-Hasna- are rejected so channel configuration cannot replace signed delivery metadata.

Signatures use HMAC-SHA256 over:

<timestamp>.<json-body>

The signature format is:

sha256=<hex digest>

Consumers can verify with:

import { verifyWebhookSignature } from "@hasna/events/signing";

const ok = verifyWebhookSignature(secret, timestamp, body, signature);

verifyWebhookSignature rejects timestamps outside a five-minute window by default. Pass an explicit toleranceMs when a consumer needs a tighter or wider replay window.

Durable Node Producer And Bun Delivery Worker

@hasna/events/durable-spool is the producer boundary for Node 20+ apps. It has no Bun runtime import and performs no network access. Each enqueue writes a mode-0600 temporary file, fsyncs it, hard-links it without replacement to an identity-keyed final name, removes the temporary file, and fsyncs the inbox directory. Concurrent producers with the same dedupeKey converge on one immutable record.

import { DurableEventSpool } from "@hasna/events/durable-spool";

const spool = new DurableEventSpool({ dataDir: process.env.HASNA_EVENTS_DIR! });
await spool.enqueue({
  id: "notes:note:123:created",
  source: "notes",
  type: "note.created",
  time: "2026-08-06T12:00:00.000Z",
  subject: "note:123",
  dedupeKey: "notes:note:123:created",
  schemaVersion: "notes.v1",
  data: {
    noteId: "123",
    createdAt: "2026-08-06T12:00:00.000Z",
    originMachine: "station03",
  },
  metadata: {},
});

@hasna/events/durable is Bun-only because it uses bun:sqlite. The broker imports committed spool records into an event and matching-channel outbox in a SQLite BEGIN IMMEDIATE transaction, then removes the spool record. SQLite WAL, unique event/dedupe identities, unique event/channel jobs, bounded leases, and persisted retry timestamps make separate workers and process restarts safe. Producer spool records and broker event rows apply the default sensitive-key redaction. Each outbox row additionally applies its channel's redact.paths before the payload is persisted or delivered. The broker initializes schema v1 only from an empty version-0 application schema. Existing v1 databases must match the complete columns, constraints, foreign keys, and indexes; malformed or newer schemas are rejected unchanged.

import { DurableEventsBroker } from "@hasna/events/durable";

const broker = new DurableEventsBroker({ dataDir: process.env.HASNA_EVENTS_DIR! });
broker.addChannel({
  id: "notes-created",
  enabled: false,
  transport: "webhook",
  filters: [{ source: "notes", type: "note.created" }],
  webhook: {
    url: "https://example.com/events/notes",
    secretRef: "env:HASNA_NOTES_WEBHOOK_SECRET",
  },
  retry: { maxAttempts: 5, backoffMs: 1_000, multiplier: 2 },
});

broker.importSpool();
await broker.drain();
broker.close();

Durable SQLite channels reject inline webhook.secret values. The default resolver supports env:VARIABLE_NAME; callers can inject a vault-backed resolver. Resolved credential values are used only to sign the in-memory HTTP request and are never stored in channel configuration, the outbox, delivery history, or status output.

Any HTTP 2xx response acknowledges delivery. The receiver therefore must return 2xx only after durably enqueueing the event and must deduplicate by dedupeKey or id. Non-2xx responses, timeouts, and unresolved runtime secrets follow the persisted retry schedule. Exhausted jobs remain dead; an operator can call retryDead({ eventId, channelId, limit }) or use events durable retry-dead without creating a second event/channel outbox identity.

The Bun CLI exposes the same operator boundary:

events --dir "$HASNA_EVENTS_DIR" durable channel https://example.com/events/notes \
  --id notes-created --source notes --type note.created \
  --secret-ref env:HASNA_NOTES_WEBHOOK_SECRET --disabled

events --dir "$HASNA_EVENTS_DIR" durable drain --limit 100
events --dir "$HASNA_EVENTS_DIR" durable work --limit 100
events --dir "$HASNA_EVENTS_DIR" durable retry-dead --limit 100
events --dir "$HASNA_EVENTS_DIR" durable status

durable drain imports and processes one bounded batch, then exits. Enqueueing alone never performs network delivery. durable work is the long-running Bun worker: it watches only the durable spool inbox, debounces file events, imports and drains immediately, wakes at the next persisted retry timestamp, and runs a low-frequency bounded reconciliation in case a filesystem notification was missed. It never watches Apple Notes or note files. SIGTERM and SIGINT stop it cleanly. Each worker claims only the job it is about to dispatch, and only the current lease owner can settle it. Delivery is still at-least-once: if a request outlives its lease, another worker may retry it, so receivers must deduplicate by dedupeKey or id. This package change does not install, start, or enable a runner; a canary deployment must supervise one durable work process explicitly.

Webhook requests time out after 15 seconds unless webhook.timeoutMs is set. Non-2xx responses and network failures are recorded as failed attempts. The compatibility JSON delivery path stores response bodies truncated after 4,096 characters; durable delivery intentionally omits response bodies, stdout, and stderr from its outbox and delivery history.

Command Transport

Command channels run a local process and pass the event on stdin and environment variables. For production task-created automation, route to tested package commands such as loops events handle todos-task rather than long-lived local scripts. Scripts like scripts/handle-event.ts are useful prototypes; repeated behavior should move into the owning open-* package with tests and bounded evidence.

await events.addChannel({
  id: "local-handler",
  enabled: true,
  transport: "command",
  filters: [{ type: "repo.*" }],
  command: {
    command: "bun",
    args: ["run", "scripts/handle-event.ts"],
  },
});

Environment variables:

• HASNA_CHANNEL_ID
• HASNA_EVENT_ID
• HASNA_EVENT_TYPE
• HASNA_EVENT_SOURCE
• HASNA_EVENT_SUBJECT
• HASNA_EVENT_SEVERITY
• HASNA_EVENT_TIME
• HASNA_EVENT_DEDUPE_KEY
• HASNA_EVENT_SCHEMA_VERSION
• HASNA_EVENT_JSON

Command processes time out after 15 seconds unless command.timeoutMs is set. Their stdout and stderr are stored on the delivery attempt and truncated after 4,096 characters. A zero exit code succeeds; other exits or signals fail.

Both implemented transports use one attempt by default. Channel retry policy can increase maxAttempts; failed attempts back off from 250 ms by a default multiplier of 2 unless overridden. The transport type union reserves email, sse, and mcp-relay, but the CLI refuses to configure them and direct dispatch currently records them as skipped.

Redaction

Events scrub obvious sensitive keys such as secret, token, password, apiKey, api_key, api-key, and authorization recursively before local storage and delivery by default. Callers that intentionally need raw local payloads can pass:

await events.emit(input, { redactSensitiveData: false });

Use channel-level paths for per-channel delivery redaction:

await events.addChannel({
  id: "secure-hook",
  enabled: true,
  transport: "webhook",
  webhook: { url: "https://example.com" },
  redact: { paths: ["data.secret", "metadata.token"] },
});

Use runtime hooks for app-specific policies:

const events = new EventsClient({
  redactors: [
    async (event) => ({
      ...event,
      metadata: { ...event.metadata, internalOnly: undefined },
    }),
  ],
});

CLI

The package exposes events and hasna-events.

Global options must come before the command group:

events --dir /tmp/events --json status

events channels add https://example.com/channels/hasna \
  --id ops \
  --type "ticket.*" \
  --secret "$HASNA_WEBHOOK_SECRET" \
  --retry-attempts 3 \
  --retry-backoff-ms 500

events channels list
events channels test ops
events channels match ops
events channels remove ops

Field filters can match nested data or metadata values. Plain --data/--metadata values are strings, which keeps ids and slugs such as 001 intact. Use --data-json or --metadata-json for typed JSON predicates. Dot paths check both nested object keys and literal dotted keys; there is no syntax to distinguish between those two forms yet. A negative predicate also matches when its field is absent. When the actual event value is an array, string filters match any primitive array member, which is useful for tag routing such as data.tags=auto:route. Use path!=value or path!=json for negative predicates such as metadata-json 'automation.no_auto!=true'. Wildcard behavior stays broad for legacy source/type/subject filters. For field paths ending in _path or .path, * matches one path segment and ** matches recursively.

events channels add loops \
  --id open-source-task-route \
  --transport command \
  --source todos \
  --type task.created \
  --timeout-ms 15000 \
  --retry-attempts 3 \
  --retry-backoff-ms 500 \
  --metadata 'project_path=/home/hasna/workspace/hasna/opensource/*' \
  --metadata-json 'route_enabled=true' \
  --metadata-json 'automation.no_auto!=true' \
  --data 'tags=auto:route' \
  --arg events \
  --arg handle \
  --arg todos-task

# Command args that begin with dashes can be passed either form:
events channels add events --id json-route --transport command --arg --json
events channels add events --id json-route --transport command --arg=--json

# For nested CLIs, put child positional args and flags after an explicit delimiter.
events channels add events --id nested-route --transport command -- handle todos-task --json

events channels match open-source-task-route \
  --source todos \
  --type task.created \
  --metadata '{"project_path":"/home/hasna/workspace/repos/hasna/events","route_enabled":true}'

events channels test open-source-task-route --honor-filters \
  --source todos \
  --type task.created \
  --metadata '{"project_path":"/tmp/outside","route_enabled":true}'

Emit, list, and replay:

events events emit ticket.created \
  --source tickets \
  --subject ticket:123 \
  --severity notice \
  --message "Ticket created" \
  --data '{"ticketId":123}'

events events list --limit 20
events events list --source tickets --type ticket.created
events events replay --type ticket.created
events events replay --type ticket.created --dry-run --limit 100
events events replay --type ticket.created --cursor "$NEXT_CURSOR" --limit 100
events events replay --dry-run

Replay cursors are opaque and tied to the same filter set (--id, --source, and --type) used to produce them. Use the nextCursor returned by the previous JSON replay response rather than constructing cursor strings in callers. A replay without --limit or --cursor processes all matching events; use those flags when callers need bounded page-by-page replay.

Machine-readable status (global flags precede status):

events --json status

The status contract reports storage runtime, event, channel, delivery, file, and transport metadata only. It does not include event payloads, webhook signing secrets, command environment values, or channel targets.

Use --json for script-friendly output and --dir <path> for isolated data. The standalone events events list command has no implicit row cap. Commands registered into another Commander program with registerEventsCommands default to the 100 most recent rows, accept a host override, and use --limit 0 to list all rows. The embedded emitter also supports --no-dedupe; the standalone CLI does not currently expose that library option.

App Integration Pattern

Apps should keep event emission near durable state changes and avoid hardcoding app-specific channels. The common pattern is:

import { EventsClient } from "@hasna/events";

const events = new EventsClient();

export async function recordDomainEvent() {
  await events.emit({
    source: "your-app",
    type: "domain.object.changed",
    subject: "object:123",
    severity: "info",
    data: { id: 123 },
  });
}

Local users and agents can configure channels once through the CLI, and every app using @hasna/events will share the same local channel config.

Development

bun test
bun run typecheck
bun run build