Refactor FBC caching

cmd/opm/serve/serve.go

@@ -5,6 +5,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"io"
 	"net"
 	"net/http"
 	endpoint "net/http/pprof"
@@ -19,17 +20,18 @@ import (
 
 	"github.com/operator-framework/operator-registry/pkg/api"
 	health "github.com/operator-framework/operator-registry/pkg/api/grpc_health_v1"
+	"github.com/operator-framework/operator-registry/pkg/cache"
 	"github.com/operator-framework/operator-registry/pkg/lib/dns"
 	"github.com/operator-framework/operator-registry/pkg/lib/graceful"
 	"github.com/operator-framework/operator-registry/pkg/lib/log"
-	"github.com/operator-framework/operator-registry/pkg/registry"
 	"github.com/operator-framework/operator-registry/pkg/server"
 )
 
 type serve struct {
-	configDir string
-	cacheDir  string
-	cacheOnly bool
+	configDir             string
+	cacheDir              string
+	cacheOnly             bool
+	cacheEnforceIntegrity bool
 
 	port           string
 	terminationLog string
@@ -59,15 +61,19 @@ startup. Changes made to the declarative config after the this command starts
 will not be reflected in the served content.
 `,
 		Args: cobra.ExactArgs(1),
-		PreRunE: func(_ *cobra.Command, args []string) error {
+		PreRun: func(_ *cobra.Command, args []string) {
 			s.configDir = args[0]
 			if s.debug {
 				logger.SetLevel(logrus.DebugLevel)
 			}
-			return nil
 		},
-		RunE: func(cmd *cobra.Command, _ []string) error {
-			return s.run(cmd.Context())
+		Run: func(cmd *cobra.Command, _ []string) {
+			if !cmd.Flags().Changed("cache-enforce-integrity") {
+				s.cacheEnforceIntegrity = s.cacheDir != "" && !s.cacheOnly
+			}
+			if err := s.run(cmd.Context()); err != nil {
+				logger.Fatal(err)
+			}
 		},
 	}
 
@@ -77,6 +83,7 @@ will not be reflected in the served content.
 	cmd.Flags().StringVar(&s.pprofAddr, "pprof-addr", "", "address of startup profiling endpoint (addr:port format)")
 	cmd.Flags().StringVar(&s.cacheDir, "cache-dir", "", "if set, sync and persist server cache directory")
 	cmd.Flags().BoolVar(&s.cacheOnly, "cache-only", false, "sync the serve cache and exit without serving")
+	cmd.Flags().BoolVar(&s.cacheEnforceIntegrity, "cache-enforce-integrity", false, "exit with error if cache is not present or has been invalidated. (default: true when --cache-dir is set and --cache-only is false, false otherwise), ")
 	return cmd
 }
 
@@ -102,11 +109,38 @@ func (s *serve) run(ctx context.Context) error {
 
 	s.logger = s.logger.WithFields(logrus.Fields{"configs": s.configDir, "port": s.port})
 
-	store, err := registry.NewQuerierFromFS(os.DirFS(s.configDir), s.cacheDir)
-	defer store.Close()
+	if s.cacheDir == "" && s.cacheEnforceIntegrity {
+		return fmt.Errorf("--cache-dir must be specified with --cache-enforce-integrity")
+	}
+
+	if s.cacheDir == "" {
+		s.cacheDir, err = os.MkdirTemp("", "opm-serve-cache-")
+		if err != nil {
+			return err
+		}
+		defer os.RemoveAll(s.cacheDir)
+	}
+
+	store, err := cache.New(s.cacheDir)
 	if err != nil {
 		return err
 	}
+	if storeCloser, ok := store.(io.Closer); ok {
+		defer storeCloser.Close()
+	}
+	if s.cacheEnforceIntegrity {
+		if err := store.CheckIntegrity(os.DirFS(s.configDir)); err != nil {
+			return err
+		}
+		if err := store.Load(); err != nil {
+			return err
+		}
+	} else {
+		if err := cache.LoadOrRebuild(store, os.DirFS(s.configDir)); err != nil {
+			return err
+		}
+	}
+
 	if s.cacheOnly {
 		return nil
 	}

go.mod

@@ -34,7 +34,7 @@ require (
 	golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4
 	golang.org/x/net v0.0.0-20220722155237-a158d28d115b
 	golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4
-	golang.org/x/sys v0.0.0-20220907062415-87db552b00fd
+	golang.org/x/sys v0.0.0-20221010170243-090e33056c14
 	google.golang.org/grpc v1.47.0
 	google.golang.org/grpc/cmd/protoc-gen-go-grpc v0.0.0-20200709232328-d8193ee9cc3e
 	google.golang.org/protobuf v1.28.0
@@ -94,6 +94,7 @@ require (
 	github.com/gogo/protobuf v1.3.2 // indirect
 	github.com/golang/groupcache v0.0.0-20210331224755-41bb18bfe9da // indirect
 	github.com/golang/protobuf v1.5.2 // indirect
+	github.com/golang/snappy v0.0.3 // indirect
 	github.com/google/cel-go v0.12.4 // indirect
 	github.com/google/gnostic v0.5.7-v3refs // indirect
 	github.com/google/gofuzz v1.1.0 // indirect
@@ -108,7 +109,7 @@ require (
 	github.com/josharian/intern v1.0.0 // indirect
 	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/kardianos/osext v0.0.0-20190222173326-2bc1f35cddc0 // indirect
-	github.com/klauspost/compress v1.11.13 // indirect
+	github.com/klauspost/compress v1.12.3 // indirect
 	github.com/mailru/easyjson v0.7.6 // indirect
 	github.com/mattn/go-isatty v0.0.12 // indirect
 	github.com/matttproud/golang_protobuf_extensions v1.0.2-0.20181231171920-c182affec369 // indirect

go.sum

@@ -338,6 +338,8 @@ github.com/golang/protobuf v1.5.2/go.mod h1:XVQd3VNwM+JqD3oG2Ue2ip4fOMUkwXdXDdiu
 github.com/golang/snappy v0.0.0-20170215233205-553a64147049/go.mod h1:/XxbfmMg8lxefKM7IXC3fBNl/7bRcc72aCRzEWrmP2Q=
 github.com/golang/snappy v0.0.0-20180518054509-2e65f85255db/go.mod h1:/XxbfmMg8lxefKM7IXC3fBNl/7bRcc72aCRzEWrmP2Q=
 github.com/golang/snappy v0.0.1/go.mod h1:/XxbfmMg8lxefKM7IXC3fBNl/7bRcc72aCRzEWrmP2Q=
+github.com/golang/snappy v0.0.3 h1:fHPg5GQYlCeLIPB9BZqMVR5nR9A+IM5zcgeTdjMYmLA=
+github.com/golang/snappy v0.0.3/go.mod h1:/XxbfmMg8lxefKM7IXC3fBNl/7bRcc72aCRzEWrmP2Q=
 github.com/google/btree v0.0.0-20180813153112-4030bb1f1f0c/go.mod h1:lNA+9X1NB3Zf8V7Ke586lFgjr2dZNuvo3lPJSGZ5JPQ=
 github.com/google/btree v1.0.0/go.mod h1:lNA+9X1NB3Zf8V7Ke586lFgjr2dZNuvo3lPJSGZ5JPQ=
 github.com/google/cel-go v0.12.4 h1:YINKfuHZ8n72tPOqSPZBwGiDpew2CJS48mdM5W8LZQU=
@@ -468,8 +470,8 @@ github.com/kisielk/errcheck v1.1.0/go.mod h1:EZBBE59ingxPouuu3KfxchcWSUPOHkagtvW
 github.com/kisielk/errcheck v1.2.0/go.mod h1:/BMXB+zMLi60iA8Vv6Ksmxu/1UDYcXs4uQLJ+jE2L00=
 github.com/kisielk/errcheck v1.5.0/go.mod h1:pFxgyoBC7bSaBwPgfKdkLd5X25qrDl4LWUI2bnpBCr8=
 github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
-github.com/klauspost/compress v1.11.13 h1:eSvu8Tmq6j2psUJqJrLcWH6K3w5Dwc+qipbaA6eVEN4=
-github.com/klauspost/compress v1.11.13/go.mod h1:aoV0uJVorq1K+umq18yTdKaF57EivdYsUV+/s2qKfXs=
+github.com/klauspost/compress v1.12.3 h1:G5AfA94pHPysR56qqrkO2pxEexdDzrpFJ6yt/VqWxVU=
+github.com/klauspost/compress v1.12.3/go.mod h1:8dP1Hq4DHOhN9w426knH3Rhby4rFm6D8eO+e+Dq5Gzg=
 github.com/konsorten/go-windows-terminal-sequences v1.0.1/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
 github.com/konsorten/go-windows-terminal-sequences v1.0.2/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
 github.com/konsorten/go-windows-terminal-sequences v1.0.3/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
@@ -942,8 +944,8 @@ golang.org/x/sys v0.0.0-20210603081109-ebe580a85c40/go.mod h1:oPkhp1MJrh7nUepCBc
 golang.org/x/sys v0.0.0-20210616094352-59db8d763f22/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20211025201205-69cdffdb9359/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220114195835-da31bd327af9/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.0.0-20220907062415-87db552b00fd h1:AZeIEzg+8RCELJYq8w+ODLVxFgLMMigSwO/ffKPEd9U=
-golang.org/x/sys v0.0.0-20220907062415-87db552b00fd/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20221010170243-090e33056c14 h1:k5II8e6QD8mITdi+okbbmR/cIyEbeXLBhy5Ha4nevyc=
+golang.org/x/sys v0.0.0-20221010170243-090e33056c14/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/term v0.0.0-20210927222741-03fcf44c2211 h1:JGgROgKl9N8DuW20oFS5gxc+lE67/N3FcwmBPMe7ArY=
 golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=

pkg/cache/cache.go

@@ -0,0 +1,104 @@
+package cache
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"io/fs"
+	"os"
+	"path/filepath"
+
+	"k8s.io/apimachinery/pkg/util/sets"
+
+	"github.com/operator-framework/operator-registry/pkg/api"
+	"github.com/operator-framework/operator-registry/pkg/registry"
+)
+
+type Cache interface {
+	registry.GRPCQuery
+
+	CheckIntegrity(fbc fs.FS) error
+	Build(fbc fs.FS) error
+	Load() error
+}
+
+func LoadOrRebuild(c Cache, fbc fs.FS) error {
+	if err := c.CheckIntegrity(fbc); err != nil {
+		if err := c.Build(fbc); err != nil {
+			return err
+		}
+	}
+	return c.Load()
+}
+
+// New creates a new Cache. It chooses a cache implementation based
+// on the files it finds in the cache directory, with a preference for the
+// latest iteration of the cache implementation. It returns an error if
+// cacheDir exists and contains unexpected files.
+func New(cacheDir string) (Cache, error) {
+	entries, err := os.ReadDir(cacheDir)
+	if err != nil && !errors.Is(err, os.ErrNotExist) {
+		return nil, fmt.Errorf("detect cache format: read cache directory: %v", err)
+	}
+	jsonCache := sets.NewString(jsonDir, jsonDigestFile)
+
+	found := sets.NewString()
+	for _, e := range entries {
+		found.Insert(e.Name())
+	}
+
+	// Preference (and currently only supported) is the JSON-based cache implementation.
+	if found.IsSuperset(jsonCache) || len(entries) == 0 {
+		return NewJSON(cacheDir), nil
+	}
+
+	// Anything else is unexpected.
+	return nil, fmt.Errorf("cache directory has unexpected contents")
+}
+
+func ensureEmptyDir(dir string, mode os.FileMode) error {
+	if err := os.MkdirAll(dir, mode); err != nil {
+		return err
+	}
+	entries, err := os.ReadDir(dir)
+	if err != nil {
+		return err
+	}
+	for _, entry := range entries {
+		if err := os.RemoveAll(filepath.Join(dir, entry.Name())); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func doesBundleProvide(ctx context.Context, c Cache, pkgName, chName, bundleName, group, version, kind string) (bool, error) {
+	apiBundle, err := c.GetBundle(ctx, pkgName, chName, bundleName)
+	if err != nil {
+		return false, fmt.Errorf("get bundle %q: %v", bundleName, err)
+	}
+	for _, gvk := range apiBundle.ProvidedApis {
+		if gvk.Group == group && gvk.Version == version && gvk.Kind == kind {
+			return true, nil
+		}
+	}
+	return false, nil
+}
+
+type sliceBundleSender []*api.Bundle
+
+func (s *sliceBundleSender) Send(b *api.Bundle) error {
+	*s = append(*s, b)
+	return nil
+}
+
+func listBundles(ctx context.Context, c Cache) ([]*api.Bundle, error) {
+	var bundleSender sliceBundleSender
+
+	err := c.SendBundles(ctx, &bundleSender)
+	if err != nil {
+		return nil, err
+	}
+
+	return bundleSender, nil
+}