411 lines
16 KiB
Go
411 lines
16 KiB
Go
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package retriever
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import (
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"context"
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stderrors "errors"
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"sync"
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"sync/atomic"
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"testing"
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"github.com/Tencent/WeKnora/internal/types"
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"github.com/Tencent/WeKnora/internal/types/interfaces"
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"github.com/stretchr/testify/assert"
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"github.com/stretchr/testify/require"
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)
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const rehydrateStoreID = "00000000-0000-0000-0000-0000000000aa"
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// fakeStoreRepo serves a single store by ID. Embedding the interface keeps the
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// fake to the one method the rehydration path uses; any other call would
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// nil-panic loudly rather than silently returning a zero value.
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type fakeStoreRepo struct {
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interfaces.VectorStoreRepository
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store *types.VectorStore
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err error
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}
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func (f *fakeStoreRepo) GetByID(_ context.Context, _ uint64, _ string) (*types.VectorStore, error) {
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return f.store, f.err
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}
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// blockingFactory models a real engine constructor: it dials, which means it
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// observes the context it is handed and aborts when that context is cancelled.
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type blockingFactory struct {
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entered chan struct{}
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release chan struct{}
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once sync.Once
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calls atomic.Int32
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}
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func newBlockingFactory() *blockingFactory {
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return &blockingFactory{entered: make(chan struct{}), release: make(chan struct{})}
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}
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func (b *blockingFactory) build(ctx context.Context, _ types.VectorStore) (
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interfaces.RetrieveEngineService, error,
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) {
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b.calls.Add(1)
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b.once.Do(func() { close(b.entered) })
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select {
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case <-b.release:
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return &mockEngineService{engineType: types.ElasticsearchRetrieverEngineType}, nil
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case <-ctx.Done():
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return nil, ctx.Err()
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}
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}
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func newRehydratingRegistry(factory interfaces.EngineFactory) *RetrieveEngineRegistry {
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return &RetrieveEngineRegistry{
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byEngineType: make(map[types.RetrieverEngineType]interfaces.RetrieveEngineService),
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byStoreID: make(map[string]interfaces.RetrieveEngineService),
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repo: &fakeStoreRepo{store: &types.VectorStore{ID: rehydrateStoreID}},
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factory: factory,
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}
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}
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// TestGetOrLoadByStoreID_LeaderCancelDoesNotPoisonWaiters pins the reason this
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// path uses DoChan with a detached build context.
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//
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// Two requests miss the registry for the same store, so they collapse into one
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// engine build. If that shared build inherits the first caller's context, the
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// first caller going away — a closed browser tab, a shutting-down worker —
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// aborts the build and hands its cancellation error to every other caller
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// waiting on it. Those callers are alive and would then be told the store is
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// unavailable, which is the very failure this rehydration exists to remove.
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func TestGetOrLoadByStoreID_LeaderCancelDoesNotPoisonWaiters(t *testing.T) {
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factory := newBlockingFactory()
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registry := newRehydratingRegistry(factory.build)
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// Installed before any caller starts: the hooks are plain fields, and a
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// caller attaches to its build before the build itself reports progress,
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// so setting them later both races and misses the first attachment.
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shared := make(chan bool, 4)
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registry.flightObserver = func(s bool) { shared <- s }
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joined := make(chan struct{}, 4)
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registry.onFlightJoin = func() { joined <- struct{}{} }
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leaderCtx, cancelLeader := context.WithCancel(context.Background())
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defer cancelLeader()
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var leaderErr error
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leaderDone := make(chan struct{})
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go func() {
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defer close(leaderDone)
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_, leaderErr = registry.GetOrLoadByStoreID(leaderCtx, 1, rehydrateStoreID)
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}()
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<-factory.entered // the build is running
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<-joined // ...and the leader is attached to it
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var (
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waiterSvc interfaces.RetrieveEngineService
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waiterErr error
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)
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waiterDone := make(chan struct{})
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go func() {
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defer close(waiterDone)
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waiterSvc, waiterErr = registry.GetOrLoadByStoreID(context.Background(), 1, rehydrateStoreID)
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}()
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// Wait for the waiter to attach before letting the build finish. Released
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// any earlier, the build would complete and register, and the waiter would
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// read that engine directly instead of ever sharing the build — which the
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// result assertions alone cannot tell apart.
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<-joined
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cancelLeader()
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<-leaderDone
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close(factory.release)
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<-waiterDone
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require.NoError(t, waiterErr, "waiter must not inherit the leader's cancellation")
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require.NotNil(t, waiterSvc, "waiter must receive the engine the shared build produced")
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assert.ErrorIs(t, leaderErr, context.Canceled, "the cancelled leader still reports its own cancellation")
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assert.Equal(t, int32(1), factory.calls.Load(), "the waiter must join the flight, not start a second build")
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require.Len(t, shared, 1, "only the waiter reaches the result branch; the leader left on its context")
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assert.Empty(t, joined, "exactly two attachments, both accounted for above")
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assert.True(t, <-shared, "the waiter must have waited on the leader's build, not run its own")
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svc, err := registry.GetByStoreID(rehydrateStoreID)
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require.NoError(t, err, "a completed build must leave the engine registered")
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assert.NotNil(t, svc)
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}
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// TestGetOrLoadByStoreID_ConcurrentMissesBuildOnce checks that a burst of
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// requests for the same missing store produces one engine, not one per caller.
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// Engine construction dials a backend, so duplicating it per request would turn
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// a cold store into a connection storm.
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func TestGetOrLoadByStoreID_ConcurrentMissesBuildOnce(t *testing.T) {
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factory := newBlockingFactory()
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registry := newRehydratingRegistry(factory.build)
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close(factory.release) // let every build finish immediately
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const callers = 16
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var wg sync.WaitGroup
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services := make([]interfaces.RetrieveEngineService, callers)
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errs := make([]error, callers)
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wg.Add(callers)
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for i := range callers {
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go func() {
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defer wg.Done()
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services[i], errs[i] = registry.GetOrLoadByStoreID(context.Background(), 1, rehydrateStoreID)
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}()
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}
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wg.Wait()
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for i := range callers {
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require.NoError(t, errs[i], "caller %d", i)
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require.NotNil(t, services[i], "caller %d", i)
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assert.Same(t, services[0], services[i], "every caller must get the same engine")
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}
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assert.Equal(t, int32(1), factory.calls.Load(), "one build for the whole burst")
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}
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// TestGetOrLoadByStoreID_FactoryPanicDoesNotCrashProcess pins the panic guard.
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// singleflight re-raises a panic from the shared build on its own goroutine,
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// where the HTTP recovery middleware cannot catch it, so an unguarded panic
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// from a third-party client constructor would end the process rather than the
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// request. Reaching the assertions below at all is the real assertion.
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func TestGetOrLoadByStoreID_FactoryPanicDoesNotCrashProcess(t *testing.T) {
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registry := newRehydratingRegistry(
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func(context.Context, types.VectorStore) (interfaces.RetrieveEngineService, error) {
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panic("client constructor exploded")
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},
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)
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svc, err := registry.GetOrLoadByStoreID(context.Background(), 1, rehydrateStoreID)
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require.ErrorIs(t, err, ErrVectorStoreUnavailable, "a panicking build is reported as retryable")
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assert.Nil(t, svc)
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_, lookupErr := registry.GetByStoreID(rehydrateStoreID)
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assert.Error(t, lookupErr, "a panicking build must leave nothing registered")
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}
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// TestGetOrLoadByStoreID_UnregisterDuringBuildIsNotUndone covers the delete
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// race: a store removed while its engine is still being built must stay
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// removed, otherwise the finishing build silently resurrects it.
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func TestGetOrLoadByStoreID_UnregisterDuringBuildIsNotUndone(t *testing.T) {
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factory := newBlockingFactory()
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registry := newRehydratingRegistry(factory.build)
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var (
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svc interfaces.RetrieveEngineService
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err error
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)
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done := make(chan struct{})
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go func() {
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defer close(done)
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svc, err = registry.GetOrLoadByStoreID(context.Background(), 1, rehydrateStoreID)
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}()
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<-factory.entered
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registry.UnregisterByStoreID(rehydrateStoreID) // delete lands mid-build
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close(factory.release)
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<-done
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require.ErrorIs(t, err, ErrVectorStoreUnavailable, "a build overtaken by a delete must not succeed")
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assert.Nil(t, svc)
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_, lookupErr := registry.GetByStoreID(rehydrateStoreID)
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assert.Error(t, lookupErr, "the deleted store must not be back in the registry")
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}
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// TestGetOrLoadByStoreID_FailedBuildEntersCooldown checks that a store whose
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// build just failed is not retried on the next request. A backend that stays
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// down would otherwise cost a full build timeout per request, in exactly the
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// outage this rehydration is meant to soften.
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func TestGetOrLoadByStoreID_FailedBuildEntersCooldown(t *testing.T) {
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var calls atomic.Int32
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registry := newRehydratingRegistry(
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func(context.Context, types.VectorStore) (interfaces.RetrieveEngineService, error) {
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calls.Add(1)
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return nil, assert.AnError
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},
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)
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_, firstErr := registry.GetOrLoadByStoreID(context.Background(), 1, rehydrateStoreID)
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_, secondErr := registry.GetOrLoadByStoreID(context.Background(), 1, rehydrateStoreID)
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require.ErrorIs(t, firstErr, ErrVectorStoreUnavailable)
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require.ErrorIs(t, secondErr, ErrVectorStoreUnavailable, "raw build errors must not leak past the sentinel")
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assert.Equal(t, int32(1), calls.Load(), "the second request is served by the cooldown, not a new build")
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// Removing the store clears the cooldown so an operator can retry at once.
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registry.UnregisterByStoreID(rehydrateStoreID)
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_, thirdErr := registry.GetOrLoadByStoreID(context.Background(), 1, rehydrateStoreID)
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require.Error(t, thirdErr)
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assert.Equal(t, int32(2), calls.Load(), "unregistering must clear the cooldown")
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}
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// TestGetOrLoadByStoreID_WithoutRepoOrFactoryIsPlainLookup pins the degraded
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// mode: a registry built without the rebuild dependencies must behave exactly
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// as it did before rehydration existed.
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func TestGetOrLoadByStoreID_WithoutRepoOrFactoryIsPlainLookup(t *testing.T) {
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registry := &RetrieveEngineRegistry{
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byEngineType: make(map[types.RetrieverEngineType]interfaces.RetrieveEngineService),
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byStoreID: make(map[string]interfaces.RetrieveEngineService),
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}
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_, err := registry.GetOrLoadByStoreID(context.Background(), 1, rehydrateStoreID)
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require.ErrorIs(t, err, ErrVectorStoreNotFound)
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registered := &mockEngineService{engineType: types.ElasticsearchRetrieverEngineType}
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registry.RegisterWithStoreID(rehydrateStoreID, registered)
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svc, err := registry.GetOrLoadByStoreID(context.Background(), 1, rehydrateStoreID)
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require.NoError(t, err)
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assert.Same(t, registered, svc, "a hit must not consult the database")
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}
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// cancellingRegistry reports a caller-side cancellation from the rebuild path,
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// the way the real registry does when the request that was waiting goes away.
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// The lookup still misses, so the factory must reach the rebuild path first.
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type cancellingRegistry struct {
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interfaces.RetrieveEngineRegistry
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}
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func (cancellingRegistry) GetByStoreID(string) (interfaces.RetrieveEngineService, error) {
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return nil, stderrors.New("store not in registry")
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}
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func (cancellingRegistry) GetOrLoadByStoreID(
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context.Context, uint64, string,
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) (interfaces.RetrieveEngineService, error) {
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return nil, context.Canceled
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}
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// TestBoundLookup_CancellationIsNotReportedAsMissingStore keeps a cancellation
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// from being reported as a missing store.
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//
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// The async delete handlers treat ErrVectorStoreNotFound as permanent and
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// answer it with asynq.SkipRetry. A shutdown cancels in-flight handlers, so
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// folding that cancellation into the sentinel would make a rolling restart
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// discard knowledge-base and index delete tasks that should have been retried,
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// leaving vector data behind with nothing scheduled to remove it.
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func TestBoundLookup_CancellationIsNotReportedAsMissingStore(t *testing.T) {
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ownership := &fakeOwnership{owned: map[string]uint64{rehydrateStoreID: 1}}
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storeID := rehydrateStoreID
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t.Run("CreateRetrieveEngineForKB", func(t *testing.T) {
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_, err := CreateRetrieveEngineForKB(
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context.Background(), cancellingRegistry{}, ownership, 1, &storeID)
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require.ErrorIs(t, err, context.Canceled, "the cancellation must reach the caller")
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require.NotErrorIs(t, err, ErrVectorStoreNotFound,
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"async handlers map this sentinel to SkipRetry and would drop the task")
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})
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t.Run("VerifyBinding", func(t *testing.T) {
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err := VerifyBinding(context.Background(), cancellingRegistry{}, ownership, 1, storeID)
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require.ErrorIs(t, err, context.Canceled, "the cancellation must reach the caller")
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require.NotErrorIs(t, err, ErrVectorStoreNotFound,
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"async handlers map this sentinel to SkipRetry and would drop the task")
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})
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}
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// TestGetOrLoadByStoreID_DatabaseFailureIsRetryable separates "the database
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// could not answer" from "the store does not exist".
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//
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// The repository reports a missing row as (nil, nil) and an outage as an
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// error, and only the first is permanent. Reporting an outage as not-found
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// would make the async delete handlers answer a passing blip with SkipRetry
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// and discard work that had nothing wrong with it.
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func TestGetOrLoadByStoreID_DatabaseFailureIsRetryable(t *testing.T) {
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registry := newRehydratingRegistry(
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func(context.Context, types.VectorStore) (interfaces.RetrieveEngineService, error) {
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t.Fatal("the engine factory must not run when the store could not be loaded")
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return nil, nil
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},
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)
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registry.repo = &fakeStoreRepo{err: stderrors.New("connection refused")}
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_, err := registry.GetOrLoadByStoreID(context.Background(), 1, rehydrateStoreID)
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require.ErrorIs(t, err, ErrVectorStoreUnavailable, "an outage is retryable")
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require.NotErrorIs(t, err, ErrVectorStoreNotFound,
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"async handlers stop retrying on not-found and would drop the task")
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}
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// TestGetOrLoadByStoreID_AbsentStoreIsNotFound is the other half: a store that
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// genuinely is not there must stay permanent, so workers stop instead of
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// retrying something that can never succeed.
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func TestGetOrLoadByStoreID_AbsentStoreIsNotFound(t *testing.T) {
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registry := newRehydratingRegistry(
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func(context.Context, types.VectorStore) (interfaces.RetrieveEngineService, error) {
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t.Fatal("the engine factory must not run for a store that does not exist")
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return nil, nil
|
||
|
|
},
|
||
|
|
)
|
||
|
|
registry.repo = &fakeStoreRepo{store: nil}
|
||
|
|
|
||
|
|
_, err := registry.GetOrLoadByStoreID(context.Background(), 1, rehydrateStoreID)
|
||
|
|
|
||
|
|
require.ErrorIs(t, err, ErrVectorStoreNotFound)
|
||
|
|
require.NotErrorIs(t, err, ErrVectorStoreUnavailable)
|
||
|
|
}
|
||
|
|
|
||
|
|
// TestBoundLookup_OwnershipCancellationIsNotAStoreVerdict covers the branch
|
||
|
|
// that runs before the registry is ever consulted.
|
||
|
|
//
|
||
|
|
// The ownership check queries the database with the caller's context, so on a
|
||
|
|
// shutdown it is normally the first place the cancellation is seen. Reporting
|
||
|
|
// it as a store verdict there would let the async handlers discard the task
|
||
|
|
// just as surely as reporting it later would.
|
||
|
|
func TestBoundLookup_OwnershipCancellationIsNotAStoreVerdict(t *testing.T) {
|
||
|
|
ownership := &fakeOwnership{err: context.Canceled}
|
||
|
|
storeID := rehydrateStoreID
|
||
|
|
|
||
|
|
_, err := CreateRetrieveEngineForKB(
|
||
|
|
context.Background(), newRehydratingRegistry(nil), ownership, 1, &storeID)
|
||
|
|
|
||
|
|
require.ErrorIs(t, err, context.Canceled, "the cancellation must reach the caller")
|
||
|
|
require.NotErrorIs(t, err, ErrVectorStoreNotFound,
|
||
|
|
"async handlers map this sentinel to SkipRetry and would drop the task")
|
||
|
|
require.NotErrorIs(t, err, ErrVectorStoreUnavailable,
|
||
|
|
"a cancellation is not a statement about the store")
|
||
|
|
}
|
||
|
|
|
||
|
|
// TestBoundLookup_OwnershipOutageIsRetryable is the neighbouring case: the
|
||
|
|
// database failed for a reason of its own, which says nothing about whether
|
||
|
|
// the store exists, so the task deserves another attempt.
|
||
|
|
func TestBoundLookup_OwnershipOutageIsRetryable(t *testing.T) {
|
||
|
|
ownership := &fakeOwnership{err: stderrors.New("connection refused")}
|
||
|
|
storeID := rehydrateStoreID
|
||
|
|
|
||
|
|
_, err := CreateRetrieveEngineForKB(
|
||
|
|
context.Background(), newRehydratingRegistry(nil), ownership, 1, &storeID)
|
||
|
|
|
||
|
|
require.ErrorIs(t, err, ErrVectorStoreUnavailable)
|
||
|
|
require.NotErrorIs(t, err, ErrVectorStoreNotFound)
|
||
|
|
}
|
||
|
|
|
||
|
|
// TestGetOrLoadByStoreID_BuildDoesNotOverwriteAConcurrentRegistration guards
|
||
|
|
// the create path against the rebuild path.
|
||
|
|
//
|
||
|
|
// Registering a store publishes its engine directly. If a rebuild that started
|
||
|
|
// earlier finished afterwards and published its own, the engine callers had
|
||
|
|
// just been given would be replaced by a second one built from the same row —
|
||
|
|
// and the first would be left running with its connections open and nobody
|
||
|
|
// holding it.
|
||
|
|
func TestGetOrLoadByStoreID_BuildDoesNotOverwriteAConcurrentRegistration(t *testing.T) {
|
||
|
|
factory := newBlockingFactory()
|
||
|
|
registry := newRehydratingRegistry(factory.build)
|
||
|
|
|
||
|
|
done := make(chan struct{})
|
||
|
|
go func() {
|
||
|
|
defer close(done)
|
||
|
|
_, _ = registry.GetOrLoadByStoreID(context.Background(), 1, rehydrateStoreID)
|
||
|
|
}()
|
||
|
|
|
||
|
|
<-factory.entered
|
||
|
|
registered := &mockEngineService{engineType: types.PostgresRetrieverEngineType}
|
||
|
|
registry.RegisterWithStoreID(rehydrateStoreID, registered)
|
||
|
|
close(factory.release)
|
||
|
|
<-done
|
||
|
|
|
||
|
|
live, err := registry.GetByStoreID(rehydrateStoreID)
|
||
|
|
require.NoError(t, err)
|
||
|
|
assert.Same(t, registered, live,
|
||
|
|
"the engine published by the registration must survive the finishing build")
|
||
|
|
}
|