feat(cache): support Redis (fanal#143)

* feat(cache): support Redis

* chore(mod): update

* feat(main): support Redis

* test: update error messages according to different errors on GitHub Actions

* feat(redis): add prefix

* fix an error

Co-authored-by: Daniel Pacak <[email protected]>

* fix an error

Co-authored-by: Daniel Pacak <[email protected]>

* fix(main): defer close

* test(redis): fix error messages

* test(redis): count current connections

Co-authored-by: Daniel Pacak <[email protected]>

* test(redis): use structs instead of string literals

Co-authored-by: Daniel Pacak <[email protected]>

Author: knqyf263

cache/redis.go

@@ -0,0 +1,140 @@
+package cache
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+
+	"github.com/go-redis/redis/v8"
+	"github.com/google/go-containerregistry/pkg/v1"
+	"golang.org/x/xerrors"
+
+	"github.com/aquasecurity/fanal/types"
+)
+
+var _ Cache = &RedisCache{}
+
+const (
+	redisPrefix = "fanal"
+)
+
+type RedisCache struct {
+	client *redis.Client
+}
+
+func NewRedisCache(options *redis.Options) RedisCache {
+	return RedisCache{
+		client: redis.NewClient(options),
+	}
+}
+
+func (c RedisCache) PutArtifact(artifactID string, artifactConfig types.ArtifactInfo) error {
+	key := fmt.Sprintf("%s::%s::%s", redisPrefix, artifactBucket, artifactID)
+	b, err := json.Marshal(artifactConfig)
+	if err != nil {
+		return xerrors.Errorf("failed to marshal artifact JSON: %w", err)
+	}
+	if err := c.client.Set(context.TODO(), key, string(b), 0).Err(); err != nil {
+		return xerrors.Errorf("unable to store artifact information in Redis cache (%s): %w", artifactID, err)
+	}
+	return nil
+}
+
+func (c RedisCache) PutBlob(blobID string, blobInfo types.BlobInfo) error {
+	if _, err := v1.NewHash(blobID); err != nil {
+		return xerrors.Errorf("invalid diffID (%s): %w", blobID, err)
+	}
+	b, err := json.Marshal(blobInfo)
+	if err != nil {
+		return xerrors.Errorf("failed to marshal blob JSON: %w", err)
+	}
+	key := fmt.Sprintf("%s::%s::%s", redisPrefix, blobBucket, blobID)
+	if err := c.client.Set(context.TODO(), key, string(b), 0).Err(); err != nil {
+		return xerrors.Errorf("unable to store blob information in Redis cache (%s): %w", blobID, err)
+	}
+	return nil
+}
+
+func (c RedisCache) GetArtifact(artifactID string) (types.ArtifactInfo, error) {
+	key := fmt.Sprintf("%s::%s::%s", redisPrefix, artifactBucket, artifactID)
+	val, err := c.client.Get(context.TODO(), key).Bytes()
+	if err == redis.Nil {
+		return types.ArtifactInfo{}, xerrors.Errorf("artifact (%s) is missing in Redis cache", artifactID)
+	} else if err != nil {
+		return types.ArtifactInfo{}, xerrors.Errorf("failed to get artifact from the Redis cache: %w", err)
+	}
+
+	var info types.ArtifactInfo
+	err = json.Unmarshal(val, &info)
+	if err != nil {
+		return types.ArtifactInfo{}, xerrors.Errorf("failed to unmarshal artifact (%s) from Redis value: %w", artifactID, err)
+	}
+	return info, nil
+}
+
+func (c RedisCache) GetBlob(blobID string) (types.BlobInfo, error) {
+	key := fmt.Sprintf("%s::%s::%s", redisPrefix, blobBucket, blobID)
+	val, err := c.client.Get(context.TODO(), key).Bytes()
+	if err == redis.Nil {
+		return types.BlobInfo{}, xerrors.Errorf("blob (%s) is missing in Redis cache", blobID)
+	} else if err != nil {
+		return types.BlobInfo{}, xerrors.Errorf("failed to get blob from the Redis cache: %w", err)
+	}
+
+	var blobInfo types.BlobInfo
+	if err = json.Unmarshal(val, &blobInfo); err != nil {
+		return types.BlobInfo{}, xerrors.Errorf("failed to unmarshal blob (%s) from Redis value: %w", blobID, err)
+	}
+	return blobInfo, nil
+}
+
+func (c RedisCache) MissingBlobs(artifactID string, blobIDs []string) (bool, []string, error) {
+	var missingArtifact bool
+	var missingBlobIDs []string
+	for _, blobID := range blobIDs {
+		blobInfo, err := c.GetBlob(blobID)
+		if err != nil {
+			// error means cache missed blob info
+			missingBlobIDs = append(missingBlobIDs, blobID)
+			continue
+		}
+		if blobInfo.SchemaVersion != types.BlobJSONSchemaVersion {
+			missingBlobIDs = append(missingBlobIDs, blobID)
+		}
+	}
+	// get artifact info
+	artifactInfo, err := c.GetArtifact(artifactID)
+	// error means cache missed artifact info
+	if err != nil {
+		return true, missingBlobIDs, nil
+	}
+	if artifactInfo.SchemaVersion != types.ArtifactJSONSchemaVersion {
+		missingArtifact = true
+	}
+	return missingArtifact, missingBlobIDs, nil
+}
+
+func (c RedisCache) Close() error {
+	return c.client.Close()
+}
+
+func (c RedisCache) Clear() error {
+	ctx := context.Background()
+
+	var cursor uint64
+	for {
+		var keys []string
+		var err error
+		keys, cursor, err = c.client.Scan(ctx, cursor, redisPrefix+"::*", 100).Result()
+		if err != nil {
+			return xerrors.Errorf("failed to perform prefix scanning: %w", err)
+		}
+		if err = c.client.Unlink(ctx, keys...).Err(); err != nil {
+			return xerrors.Errorf("failed to unlink redis keys: %w", err)
+		}
+		if cursor == 0 {
+			break
+		}
+	}
+	return nil
+}