zzstoatzz.io
prefect server in zig
1# zig compatibility notes
2
3comparison of zig implementation with python prefect server.
4
5## RetryFailedFlows
6
7### matching behavior ✓
8
9| aspect | python | zig |
10|--------|--------|-----|
11| from_states | {RUNNING} | StateTypeSet.init(&.{.RUNNING}) |
12| to_states | {FAILED} | StateTypeSet.init(&.{.FAILED}) |
13| retry check | `retries is None or run_count > retries` | `ctx.retries orelse return; if (ctx.run_count > max_retries) return;` |
14| scheduled time | `now + timedelta(seconds=retry_delay or 0)` | `now_us + delay_seconds * 1_000_000` |
15| retry state | `AwaitingRetry` (SCHEDULED) | `SCHEDULED` with name "AwaitingRetry" |
16| response | `reject_transition(state, reason="Retrying")` | `REJECT` status |
17
18### implemented ✓
19
20| behavior | status |
21|----------|--------|
22| retry_type = "in_process" on retry | ✓ via `set_retry_type_in_process` flag |
23| resuming = false on retry | ✓ via `set_resuming_false` flag |
24| pause_keys = [] on retry | ✓ via `clear_pause_keys` flag |
25| retry_type = null when exhausted | ✓ via `clear_retry_type` flag |
26
27### not needed
28
29- **old client compatibility** (API < 0.8.3): python resets failed task runs to AwaitingRetry state - not needed for new clients
30
31## schema compatibility
32
33### empirical_policy JSON
34
35python schema:
36```json
37{
38 "retries": int | null,
39 "retry_delay": int | null,
40 "pause_keys": [],
41 "resuming": false,
42 "retry_type": null | "in_process" | "reschedule",
43 "max_retries": 0, // deprecated
44 "retry_delay_seconds": 0 // deprecated
45}
46```
47
48zig reads: `retries`, `retry_delay` from this JSON
49zig stores: as TEXT (sqlite) or JSONB (postgres) - compatible
50
51### storage types
52
53| column | postgres python | postgres zig | sqlite python | sqlite zig |
54|--------|-----------------|--------------|---------------|------------|
55| id | UUID | UUID | CHAR(36) | CHAR(36) |
56| timestamps | TIMESTAMP(tz) | TIMESTAMP(tz) | DATETIME | DATETIME |
57| empirical_policy | JSONB | JSONB | JSON | TEXT |
58
59## migration path
60
61our zig server stores data compatible with python prefect server:
62- UUIDs as standard format
63- timestamps as ISO 8601 UTC
64- JSON/JSONB for policy fields
65
66data created by zig server can be read by python server (and vice versa).