assay-workflow 0.1.8

Durable workflow engine with REST+SSE API, PostgreSQL/SQLite backends. Embeddable library or standalone server.
Documentation
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
pub mod postgres;
pub mod sqlite;

use std::future::Future;

use crate::types::*;

/// Core storage trait for the workflow engine.
///
/// All database access goes through this trait. Methods that operate on
/// namespace-scoped data take a `namespace` parameter. The "main"
/// namespace is always available.
///
/// All methods return `Send` futures so they can be used from `tokio::spawn`.
pub trait WorkflowStore: Send + Sync + 'static {
    // ── Namespaces ─────────────────────────────────────────

    fn create_namespace(
        &self,
        name: &str,
    ) -> impl Future<Output = anyhow::Result<()>> + Send;

    fn list_namespaces(
        &self,
    ) -> impl Future<Output = anyhow::Result<Vec<NamespaceRecord>>> + Send;

    fn delete_namespace(
        &self,
        name: &str,
    ) -> impl Future<Output = anyhow::Result<bool>> + Send;

    fn get_namespace_stats(
        &self,
        namespace: &str,
    ) -> impl Future<Output = anyhow::Result<NamespaceStats>> + Send;

    // ── Workflows ──────────────────────────────────────────

    fn create_workflow(
        &self,
        workflow: &WorkflowRecord,
    ) -> impl Future<Output = anyhow::Result<()>> + Send;

    fn get_workflow(
        &self,
        id: &str,
    ) -> impl Future<Output = anyhow::Result<Option<WorkflowRecord>>> + Send;

    fn list_workflows(
        &self,
        namespace: &str,
        status: Option<WorkflowStatus>,
        workflow_type: Option<&str>,
        search_attrs_filter: Option<&str>,
        limit: i64,
        offset: i64,
    ) -> impl Future<Output = anyhow::Result<Vec<WorkflowRecord>>> + Send;

    /// List workflows in terminal states whose `completed_at` is older than
    /// `cutoff` and which haven't been archived yet. Used by the optional
    /// S3 archival background task to batch candidates.
    fn list_archivable_workflows(
        &self,
        cutoff: f64,
        limit: i64,
    ) -> impl Future<Output = anyhow::Result<Vec<WorkflowRecord>>> + Send;

    /// Mark a workflow as archived (records `archived_at` + `archive_uri`)
    /// and purge its events, activities, timers, signals, and snapshots.
    /// The workflow record itself is preserved so `GET /workflows/{id}`
    /// still resolves with an archive pointer.
    fn mark_archived_and_purge(
        &self,
        workflow_id: &str,
        archive_uri: &str,
        archived_at: f64,
    ) -> impl Future<Output = anyhow::Result<()>> + Send;

    /// Merge a JSON object patch into the workflow's `search_attributes`.
    /// Keys in the patch overwrite existing keys; keys already present but
    /// not in the patch are preserved. If the current column is NULL, the
    /// patch becomes the new value.
    fn upsert_search_attributes(
        &self,
        workflow_id: &str,
        patch_json: &str,
    ) -> impl Future<Output = anyhow::Result<()>> + Send;

    fn update_workflow_status(
        &self,
        id: &str,
        status: WorkflowStatus,
        result: Option<&str>,
        error: Option<&str>,
    ) -> impl Future<Output = anyhow::Result<()>> + Send;

    fn claim_workflow(
        &self,
        id: &str,
        worker_id: &str,
    ) -> impl Future<Output = anyhow::Result<bool>> + Send;

    // ── Workflow-task dispatch (Phase 9) ────────────────────

    /// Mark a workflow as having new events that need a worker to replay it.
    /// Idempotent — calling repeatedly is fine. Cleared by `claim_workflow_task`.
    fn mark_workflow_dispatchable(
        &self,
        workflow_id: &str,
    ) -> impl Future<Output = anyhow::Result<()>> + Send;

    /// Atomically claim the oldest dispatchable workflow on a queue. Sets
    /// `dispatch_claimed_by` and `dispatch_last_heartbeat`, clears
    /// `needs_dispatch`. Returns the workflow record or None if nothing
    /// is available.
    fn claim_workflow_task(
        &self,
        task_queue: &str,
        worker_id: &str,
    ) -> impl Future<Output = anyhow::Result<Option<WorkflowRecord>>> + Send;

    /// Release a workflow task's dispatch lease (called when the worker
    /// submits its commands batch). Only succeeds if `dispatch_claimed_by`
    /// matches the calling worker.
    fn release_workflow_task(
        &self,
        workflow_id: &str,
        worker_id: &str,
    ) -> impl Future<Output = anyhow::Result<()>> + Send;

    /// Forcibly release dispatch leases whose worker hasn't heartbeat'd
    /// within `timeout_secs`. Used by the engine's background poller to
    /// recover from worker crashes. Returns how many leases were released
    /// (each becomes claimable again, with `needs_dispatch=true`).
    fn release_stale_dispatch_leases(
        &self,
        now: f64,
        timeout_secs: f64,
    ) -> impl Future<Output = anyhow::Result<u64>> + Send;

    // ── Events ─────────────────────────────────────────────

    fn append_event(
        &self,
        event: &WorkflowEvent,
    ) -> impl Future<Output = anyhow::Result<i64>> + Send;

    fn list_events(
        &self,
        workflow_id: &str,
    ) -> impl Future<Output = anyhow::Result<Vec<WorkflowEvent>>> + Send;

    fn get_event_count(
        &self,
        workflow_id: &str,
    ) -> impl Future<Output = anyhow::Result<i64>> + Send;

    // ── Activities ──────────────────────────────────────────

    fn create_activity(
        &self,
        activity: &WorkflowActivity,
    ) -> impl Future<Output = anyhow::Result<i64>> + Send;

    /// Look up an activity by its primary key.
    fn get_activity(
        &self,
        id: i64,
    ) -> impl Future<Output = anyhow::Result<Option<WorkflowActivity>>> + Send;

    /// Look up an activity by its workflow-relative sequence number.
    /// Used for idempotent scheduling: the engine checks if (workflow_id, seq)
    /// already exists before creating a new row.
    fn get_activity_by_workflow_seq(
        &self,
        workflow_id: &str,
        seq: i32,
    ) -> impl Future<Output = anyhow::Result<Option<WorkflowActivity>>> + Send;

    fn claim_activity(
        &self,
        task_queue: &str,
        worker_id: &str,
    ) -> impl Future<Output = anyhow::Result<Option<WorkflowActivity>>> + Send;

    /// Re-queue an activity for retry: clears the running state
    /// (status→PENDING, claimed_by/started_at cleared), bumps `attempt`,
    /// and sets `scheduled_at = now + backoff` so the next claim_activity
    /// won't pick it up before the backoff elapses.
    fn requeue_activity_for_retry(
        &self,
        id: i64,
        next_attempt: i32,
        next_scheduled_at: f64,
    ) -> impl Future<Output = anyhow::Result<()>> + Send;

    fn complete_activity(
        &self,
        id: i64,
        result: Option<&str>,
        error: Option<&str>,
        failed: bool,
    ) -> impl Future<Output = anyhow::Result<()>> + Send;

    fn heartbeat_activity(
        &self,
        id: i64,
        details: Option<&str>,
    ) -> impl Future<Output = anyhow::Result<()>> + Send;

    fn get_timed_out_activities(
        &self,
        now: f64,
    ) -> impl Future<Output = anyhow::Result<Vec<WorkflowActivity>>> + Send;

    // ── Timers ──────────────────────────────────────────────

    /// Mark all PENDING activities of a workflow as CANCELLED so workers
    /// that haven't claimed them yet won't pick them up. Returns the
    /// number of rows affected. Does NOT touch RUNNING activities — those
    /// will see the cancellation when they next heartbeat or complete.
    fn cancel_pending_activities(
        &self,
        workflow_id: &str,
    ) -> impl Future<Output = anyhow::Result<u64>> + Send;

    /// Mark all unfired timers of a workflow as fired without firing
    /// (effectively removing them from the timer poller). Returns the
    /// number of rows affected.
    fn cancel_pending_timers(
        &self,
        workflow_id: &str,
    ) -> impl Future<Output = anyhow::Result<u64>> + Send;

    fn create_timer(
        &self,
        timer: &WorkflowTimer,
    ) -> impl Future<Output = anyhow::Result<i64>> + Send;

    /// Look up an existing timer by its workflow-relative seq. Used by the
    /// engine for idempotent ScheduleTimer (deterministic replay can call
    /// schedule_timer for the same seq more than once on retries).
    fn get_timer_by_workflow_seq(
        &self,
        workflow_id: &str,
        seq: i32,
    ) -> impl Future<Output = anyhow::Result<Option<WorkflowTimer>>> + Send;

    fn fire_due_timers(
        &self,
        now: f64,
    ) -> impl Future<Output = anyhow::Result<Vec<WorkflowTimer>>> + Send;

    // ── Signals ─────────────────────────────────────────────

    fn send_signal(
        &self,
        signal: &WorkflowSignal,
    ) -> impl Future<Output = anyhow::Result<i64>> + Send;

    fn consume_signals(
        &self,
        workflow_id: &str,
        name: &str,
    ) -> impl Future<Output = anyhow::Result<Vec<WorkflowSignal>>> + Send;

    // ── Schedules ───────────────────────────────────────────

    fn create_schedule(
        &self,
        schedule: &WorkflowSchedule,
    ) -> impl Future<Output = anyhow::Result<()>> + Send;

    fn get_schedule(
        &self,
        namespace: &str,
        name: &str,
    ) -> impl Future<Output = anyhow::Result<Option<WorkflowSchedule>>> + Send;

    fn list_schedules(
        &self,
        namespace: &str,
    ) -> impl Future<Output = anyhow::Result<Vec<WorkflowSchedule>>> + Send;

    fn update_schedule_last_run(
        &self,
        namespace: &str,
        name: &str,
        last_run_at: f64,
        next_run_at: f64,
        workflow_id: &str,
    ) -> impl Future<Output = anyhow::Result<()>> + Send;

    fn delete_schedule(
        &self,
        namespace: &str,
        name: &str,
    ) -> impl Future<Output = anyhow::Result<bool>> + Send;

    /// Apply an in-place patch to a schedule. Only fields present on
    /// `patch` are updated; the rest keep their current values. Returns
    /// the updated record, or `None` if the schedule doesn't exist.
    ///
    /// The scheduler's `next_run_at` is recomputed from the new
    /// `cron_expr` + `timezone` on the next evaluation tick, so a PATCH
    /// takes effect within the scheduler's poll interval.
    fn update_schedule(
        &self,
        namespace: &str,
        name: &str,
        patch: &SchedulePatch,
    ) -> impl Future<Output = anyhow::Result<Option<WorkflowSchedule>>> + Send;

    /// Flip a schedule's `paused` flag. Returns the updated record, or
    /// `None` if the schedule doesn't exist.
    ///
    /// A paused schedule is skipped by the scheduler; resuming it
    /// doesn't backfill missed fires — the next fire is whatever the
    /// cron expression says, starting from now.
    fn set_schedule_paused(
        &self,
        namespace: &str,
        name: &str,
        paused: bool,
    ) -> impl Future<Output = anyhow::Result<Option<WorkflowSchedule>>> + Send;

    // ── Workers ─────────────────────────────────────────────

    fn register_worker(
        &self,
        worker: &WorkflowWorker,
    ) -> impl Future<Output = anyhow::Result<()>> + Send;

    fn heartbeat_worker(
        &self,
        id: &str,
        now: f64,
    ) -> impl Future<Output = anyhow::Result<()>> + Send;

    fn list_workers(
        &self,
        namespace: &str,
    ) -> impl Future<Output = anyhow::Result<Vec<WorkflowWorker>>> + Send;

    fn remove_dead_workers(
        &self,
        cutoff: f64,
    ) -> impl Future<Output = anyhow::Result<Vec<String>>> + Send;

    // ── API Keys ────────────────────────────────────────────

    fn create_api_key(
        &self,
        key_hash: &str,
        prefix: &str,
        label: Option<&str>,
        created_at: f64,
    ) -> impl Future<Output = anyhow::Result<()>> + Send;

    fn validate_api_key(
        &self,
        key_hash: &str,
    ) -> impl Future<Output = anyhow::Result<bool>> + Send;

    fn list_api_keys(
        &self,
    ) -> impl Future<Output = anyhow::Result<Vec<ApiKeyRecord>>> + Send;

    fn revoke_api_key(
        &self,
        prefix: &str,
    ) -> impl Future<Output = anyhow::Result<bool>> + Send;

    /// Return true iff the `api_keys` table has no rows. Used by the HTTP layer
    /// to identify the first-ever key-creation window (where the `POST
    /// /api/v1/api-keys` endpoint is callable without authentication).
    fn api_keys_empty(&self) -> impl Future<Output = anyhow::Result<bool>> + Send;

    /// Find an existing API key by its label. Returns None if no key has this
    /// label (or `label` is NULL). Used to implement idempotent key creation:
    /// a second `POST /api/v1/api-keys { label, idempotent: true }` call hits
    /// this method and returns the existing record's metadata (without a
    /// plaintext, which is only ever retrievable at generation time).
    fn get_api_key_by_label(
        &self,
        label: &str,
    ) -> impl Future<Output = anyhow::Result<Option<ApiKeyRecord>>> + Send;

    // ── Child Workflows ─────────────────────────────────────

    fn list_child_workflows(
        &self,
        parent_id: &str,
    ) -> impl Future<Output = anyhow::Result<Vec<WorkflowRecord>>> + Send;

    // ── Snapshots ───────────────────────────────────────────

    fn create_snapshot(
        &self,
        workflow_id: &str,
        event_seq: i32,
        state_json: &str,
    ) -> impl Future<Output = anyhow::Result<()>> + Send;

    fn get_latest_snapshot(
        &self,
        workflow_id: &str,
    ) -> impl Future<Output = anyhow::Result<Option<WorkflowSnapshot>>> + Send;

    // ── Queue Stats ─────────────────────────────────────────

    fn get_queue_stats(
        &self,
        namespace: &str,
    ) -> impl Future<Output = anyhow::Result<Vec<QueueStats>>> + Send;

    // ── Leader Election ─────────────────────────────────────

    /// Try to acquire the scheduler lock for leader election.
    /// Returns true if this instance should run the cron scheduler.
    ///
    /// - SQLite: always returns true (single-instance assumed)
    /// - Postgres: uses pg_try_advisory_lock (only one instance wins)
    fn try_acquire_scheduler_lock(
        &self,
    ) -> impl Future<Output = anyhow::Result<bool>> + Send;
}

/// API key metadata (hash is never exposed).
#[derive(Clone, Debug, serde::Serialize, utoipa::ToSchema)]
pub struct ApiKeyRecord {
    pub prefix: String,
    pub label: Option<String>,
    pub created_at: f64,
}

/// Namespace record.
#[derive(Clone, Debug, serde::Serialize, serde::Deserialize, utoipa::ToSchema)]
pub struct NamespaceRecord {
    pub name: String,
    pub created_at: f64,
}

/// Namespace-level statistics.
#[derive(Clone, Debug, serde::Serialize, serde::Deserialize, utoipa::ToSchema)]
pub struct NamespaceStats {
    pub namespace: String,
    pub total_workflows: i64,
    pub running: i64,
    pub pending: i64,
    pub completed: i64,
    pub failed: i64,
    pub schedules: i64,
    pub workers: i64,
}

/// Task queue statistics.
#[derive(Clone, Debug, serde::Serialize, serde::Deserialize, utoipa::ToSchema)]
pub struct QueueStats {
    pub queue: String,
    pub pending_activities: i64,
    pub running_activities: i64,
    pub workers: i64,
}