chore: use database in current context for file cache (#18490)

Using the db.Store when in a TX causes a deadlock for dbmem.
In production, this can cause a deadlock if at the current conn pool
limit.

coderd/files/cache_test.go

@@ -8,8 +8,8 @@ import (
 
 	"github.com/google/uuid"
 	"github.com/prometheus/client_golang/prometheus"
-	"github.com/spf13/afero"
 	"github.com/stretchr/testify/require"
+	"go.uber.org/mock/gomock"
 	"golang.org/x/sync/errgroup"
 
 	"cdr.dev/slog/sloggers/slogtest"
@@ -18,6 +18,7 @@ import (
 	"github.com/coder/coder/v2/coderd/database"
 	"github.com/coder/coder/v2/coderd/database/dbauthz"
 	"github.com/coder/coder/v2/coderd/database/dbgen"
+	"github.com/coder/coder/v2/coderd/database/dbmock"
 	"github.com/coder/coder/v2/coderd/database/dbtestutil"
 	"github.com/coder/coder/v2/coderd/files"
 	"github.com/coder/coder/v2/coderd/rbac"
@@ -58,7 +59,7 @@ func TestCacheRBAC(t *testing.T) {
 		require.Equal(t, 0, cache.Count())
 		rec.Reset()
 
-		_, err := cache.Acquire(nobody, file.ID)
+		_, err := cache.Acquire(nobody, db, file.ID)
 		require.Error(t, err)
 		require.True(t, rbac.IsUnauthorizedError(err))
 
@@ -75,18 +76,18 @@ func TestCacheRBAC(t *testing.T) {
 		require.Equal(t, 0, cache.Count())
 
 		// Read the file with a file reader to put it into the cache.
-		a, err := cache.Acquire(cacheReader, file.ID)
+		a, err := cache.Acquire(cacheReader, db, file.ID)
 		require.NoError(t, err)
 		require.Equal(t, 1, cache.Count())
 
 		// "nobody" should not be able to read the file.
-		_, err = cache.Acquire(nobody, file.ID)
+		_, err = cache.Acquire(nobody, db, file.ID)
 		require.Error(t, err)
 		require.True(t, rbac.IsUnauthorizedError(err))
 		require.Equal(t, 1, cache.Count())
 
 		// UserReader can
-		b, err := cache.Acquire(userReader, file.ID)
+		b, err := cache.Acquire(userReader, db, file.ID)
 		require.NoError(t, err)
 		require.Equal(t, 1, cache.Count())
 
@@ -110,16 +111,21 @@ func TestConcurrency(t *testing.T) {
 	ctx := dbauthz.AsFileReader(t.Context())
 
 	const fileSize = 10
-	emptyFS := afero.NewIOFS(afero.NewReadOnlyFs(afero.NewMemMapFs()))
 	var fetches atomic.Int64
 	reg := prometheus.NewRegistry()
-	c := files.New(func(_ context.Context, _ uuid.UUID) (files.CacheEntryValue, error) {
+
+	dbM := dbmock.NewMockStore(gomock.NewController(t))
+	dbM.EXPECT().GetFileByID(gomock.Any(), gomock.Any()).DoAndReturn(func(mTx context.Context, fileID uuid.UUID) (database.File, error) {
 		fetches.Add(1)
-		// Wait long enough before returning to make sure that all of the goroutines
+		// Wait long enough before returning to make sure that all the goroutines
 		// will be waiting in line, ensuring that no one duplicated a fetch.
 		time.Sleep(testutil.IntervalMedium)
-		return files.CacheEntryValue{FS: emptyFS, Size: fileSize}, nil
-	}, reg, &coderdtest.FakeAuthorizer{})
+		return database.File{
+			Data: make([]byte, fileSize),
+		}, nil
+	}).AnyTimes()
+
+	c := files.New(reg, &coderdtest.FakeAuthorizer{})
 
 	batches := 1000
 	groups := make([]*errgroup.Group, 0, batches)
@@ -137,7 +143,7 @@ func TestConcurrency(t *testing.T) {
 			g.Go(func() error {
 				// We don't bother to Release these references because the Cache will be
 				// released at the end of the test anyway.
-				_, err := c.Acquire(ctx, id)
+				_, err := c.Acquire(ctx, dbM, id)
 				return err
 			})
 		}
@@ -164,14 +170,15 @@ func TestRelease(t *testing.T) {
 	ctx := dbauthz.AsFileReader(t.Context())
 
 	const fileSize = 10
-	emptyFS := afero.NewIOFS(afero.NewReadOnlyFs(afero.NewMemMapFs()))
 	reg := prometheus.NewRegistry()
-	c := files.New(func(_ context.Context, _ uuid.UUID) (files.CacheEntryValue, error) {
-		return files.CacheEntryValue{
-			FS:   emptyFS,
-			Size: fileSize,
+	dbM := dbmock.NewMockStore(gomock.NewController(t))
+	dbM.EXPECT().GetFileByID(gomock.Any(), gomock.Any()).DoAndReturn(func(mTx context.Context, fileID uuid.UUID) (database.File, error) {
+		return database.File{
+			Data: make([]byte, fileSize),
 		}, nil
-	}, reg, &coderdtest.FakeAuthorizer{})
+	}).AnyTimes()
+
+	c := files.New(reg, &coderdtest.FakeAuthorizer{})
 
 	batches := 100
 	ids := make([]uuid.UUID, 0, batches)
@@ -184,9 +191,8 @@ func TestRelease(t *testing.T) {
 	batchSize := 10
 	for openedIdx, id := range ids {
 		for batchIdx := range batchSize {
-			it, err := c.Acquire(ctx, id)
+			it, err := c.Acquire(ctx, dbM, id)
 			require.NoError(t, err)
-			require.Equal(t, emptyFS, it.FS)
 			releases[id] = append(releases[id], it.Close)
 
 			// Each time a new file is opened, the metrics should be updated as so:
@@ -257,7 +263,7 @@ func cacheAuthzSetup(t *testing.T) (database.Store, *files.Cache, *coderdtest.Re
 
 	// Dbauthz wrap the db
 	db = dbauthz.New(db, rec, logger, coderdtest.AccessControlStorePointer())
-	c := files.NewFromStore(db, reg, rec)
+	c := files.New(reg, rec)
 	return db, c, rec
 }