* feat: support defer_on_missing_source for pending flow creation
Add `defer_on_missing_source` flow option that allows creating flows
even when source tables do not yet exist. The flow enters a pending
state and is automatically activated when source tables become available.
Key changes:
- New `FlowStatus::PendingSources` and fields in `FlowInfoValue` for
unresolved source table names and last activation error
- `defer_on_missing_source` create-time-only option: stripped from
runtime/flownode `CreateRequest` but preserved in metadata for
SQL round-trip (`SHOW CREATE FLOW`, `information_schema.flows`)
- `CreateFlowProcedure` creates pending metadata when sources are
missing and `defer_on_missing_source=true`; falls back to
`FlowType::Batching` for missing-source flows
- `PendingFlowReconcileManager` in meta-srv periodically checks
pending flows and activates them when source tables resolve
- `ActivatePendingFlowProcedure` handles activation: allocates peers,
creates flows on flownodes, updates metadata, invalidates cache
- `OR REPLACE` properly handles pending<->active transitions,
including peer allocation and flownode flow teardown
- `FlowMetadataAllocator::alloc_peers` for peer allocation at
activation time
- Validated flow options: only `defer_on_missing_source` allowed;
unknown options rejected
- Known issue: standalone mode does not support flownodes, so
pending flow flush/sink behavior covered only in distributed
sqlness; operator and meta unit tests cover activation logic
Tests:
- operator `determine_flow_type_for_source_state` (3 passed)
- common-meta `create_flow` (19 passed) including replacement
- common-meta `activate_flow` (4 passed)
- meta-srv `flow` (11 passed)
- sqlness: `flow_pending` covers create/replace/round-trip
Signed-off-by: discord9 <discord9@163.com>
* chore: simplify pending flow PR scope
Reduce PR #8124 to the metadata-only MVP after complexity review.
Changes:
- Remove automatic activation procedure and meta-srv reconcile wiring
- Remove activation tests and activation-only metadata fields
- Reject cross-state pending<->active `OR REPLACE` transitions for now
- Keep pending metadata creation and SQL round-trip behavior
- Allow `DROP FLOW` for pending flows without routes
- Reduce flow_pending sqlness to metadata/round-trip/drop coverage only
Deferred follow-ups are documented locally in `.tmp/tasks/pending-defer-semantics/deferred-followups.md` and intentionally not committed.
Tests:
- `cargo test -p operator determine_flow_type_for_source_state`
- `cargo test -p common-meta create_flow`
- `cargo test -p common-meta drop_flow`
- `cargo sqlness bare --test-filter flow_pending --bins-dir /mnt/nvme_rust/rust-targets/pending_defer/debug`
Signed-off-by: discord9 <discord9@163.com>
* test: cover pending flow metadata edge cases
Signed-off-by: discord9 <discord9@163.com>
* test: fix pending flow metadata test lint
Signed-off-by: discord9 <discord9@163.com>
* docs: document pending flow metadata fields
Signed-off-by: discord9 <discord9@163.com>
* chore: more sleep when test
Signed-off-by: discord9 <discord9@163.com>
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Signed-off-by: discord9 <discord9@163.com>
