client/db: prune archived orders

client/app/config.go

@@ -22,17 +22,18 @@ import (
 )
 
 const (
-	defaultRPCCertFile = "rpc.cert"
-	defaultRPCKeyFile  = "rpc.key"
-	defaultMainnetHost = "127.0.0.1"
-	defaultTestnetHost = "127.0.0.2"
-	defaultSimnetHost  = "127.0.0.3"
-	walletPairOneHost  = "127.0.0.6"
-	walletPairTwoHost  = "127.0.0.7"
-	defaultRPCPort     = "5757"
-	defaultWebPort     = "5758"
-	defaultLogLevel    = "debug"
-	configFilename     = "dexc.conf"
+	defaultRPCCertFile      = "rpc.cert"
+	defaultRPCKeyFile       = "rpc.key"
+	defaultMainnetHost      = "127.0.0.1"
+	defaultTestnetHost      = "127.0.0.2"
+	defaultSimnetHost       = "127.0.0.3"
+	walletPairOneHost       = "127.0.0.6"
+	walletPairTwoHost       = "127.0.0.7"
+	defaultRPCPort          = "5757"
+	defaultWebPort          = "5758"
+	defaultLogLevel         = "debug"
+	configFilename          = "dexc.conf"
+	defaultArchiveSizeLimit = 1000
 )
 
 var (
@@ -106,6 +107,8 @@ type CoreConfig struct {
 	UnlockCoinsOnLogin bool `long:"release-wallet-coins" description:"On login or wallet creation, instruct the wallet to release any coins that it may have locked."`
 
 	ExtensionModeFile string `long:"extension-mode-file" description:"path to a file that specifies options for running core as an extension."`
+
+	ArchiveSizeLimit uint64 `long:"archivesize" description:"the maximum number of orders to be archived before deleting the oldest"`
 }
 
 // WebConfig encapsulates the configuration needed for the web server.
@@ -213,6 +216,7 @@ func (cfg *Config) Core(log dex.Logger) *core.Config {
 		NoAutoWalletLock:   cfg.NoAutoWalletLock,
 		NoAutoDBBackup:     cfg.NoAutoDBBackup,
 		ExtensionModeFile:  cfg.ExtensionModeFile,
+		ArchiveSizeLimit:   cfg.ArchiveSizeLimit,
 	}
 }
 
@@ -223,6 +227,9 @@ var DefaultConfig = Config{
 	RPCConfig: RPCConfig{
 		CertHosts: []string{defaultTestnetHost, defaultSimnetHost, defaultMainnetHost},
 	},
+	CoreConfig: CoreConfig{
+		ArchiveSizeLimit: defaultArchiveSizeLimit,
+	},
 }
 
 // ParseCLIConfig parses the command-line arguments into the provided struct

client/core/core.go

@@ -1433,6 +1433,9 @@ type Config struct {
 	// for running core in extension mode, which gives the caller options for
 	// e.g. limiting the ability to configure wallets.
 	ExtensionModeFile string
+	// ArchiveSizeLimit is the maximum number of orders that will be archived
+	// before we start deleting the oldest.
+	ArchiveSizeLimit uint64
 }
 
 // locale is data associated with the currently selected language.
@@ -1515,6 +1518,7 @@ func New(cfg *Config) (*Core, error) {
 	}
 	dbOpts := bolt.Opts{
 		BackupOnShutdown: !cfg.NoAutoDBBackup,
+		ArchiveSizeLimit: cfg.ArchiveSizeLimit,
 	}
 	boltDB, err := bolt.NewDB(cfg.DBPath, cfg.Logger.SubLogger("DB"), dbOpts)
 	if err != nil {

client/db/bolt/db.go

@@ -14,6 +14,7 @@ import (
 	"path/filepath"
 	"sort"
 	"strings"
+	"sync"
 	"time"
 
 	"decred.org/dcrdex/client/db"
@@ -138,6 +139,7 @@ var (
 // Opts is a set of options for the DB.
 type Opts struct {
 	BackupOnShutdown bool // default is true
+	ArchiveSizeLimit uint64
 }
 
 var defaultOpts = Opts{
@@ -234,8 +236,29 @@ func (db *BoltDB) fileSize(path string) int64 {
 
 // Run waits for context cancellation and closes the database.
 func (db *BoltDB) Run(ctx context.Context) {
+	var wg sync.WaitGroup
+	wg.Add(1)
+	go func() {
+		defer wg.Done()
+		tick := time.After(time.Minute)
+		for {
+			select {
+			case <-tick:
+			case <-ctx.Done():
+				return
+			}
+			if err := db.pruneArchivedOrders(); err != nil {
+				db.log.Errorf("Error cleaning archive: %v", err)
+			}
+			tick = time.After(time.Minute * 30)
+		}
+	}()
+
 	<-ctx.Done() // wait for shutdown to backup and compact
 
+	// Wait for archive cleaner to exit.
+	wg.Wait()
+
 	// Create a backup in the backups folder.
 	if db.opts.BackupOnShutdown {
 		db.log.Infof("Backing up database...")
@@ -408,6 +431,129 @@ func (db *BoltDB) SetPrimaryCredentials(creds *dexdb.PrimaryCredentials) error {
 	})
 }
 
+func (db *BoltDB) pruneArchivedOrders() error {
+	var archiveSizeLimit uint64 = 1000
+	if db.opts.ArchiveSizeLimit != 0 {
+		archiveSizeLimit = db.opts.ArchiveSizeLimit
+	}
+
+	return db.Update(func(tx *bbolt.Tx) error {
+		archivedOB := tx.Bucket(archivedOrdersBucket)
+		if archivedOB == nil {
+			return fmt.Errorf("failed to open %s bucket", string(archivedOrdersBucket))
+		}
+
+		// We won't delete any orders with active matches.
+		activeMatches := tx.Bucket(activeMatchesBucket)
+		if activeMatches == nil {
+			return fmt.Errorf("failed to open %s bucket", string(activeMatchesBucket))
+		}
+		oidsWithActiveMatches := make(map[order.OrderID]struct{}, 0)
+		if err := activeMatches.ForEach(func(k, _ []byte) error {
+			mBkt := activeMatches.Bucket(k)
+			if mBkt == nil {
+				return fmt.Errorf("error getting match bucket %x", k)
+			}
+			var oid order.OrderID
+			copy(oid[:], mBkt.Get(orderIDKey))
+			oidsWithActiveMatches[oid] = struct{}{}
+			return nil
+		}); err != nil {
+			return fmt.Errorf("error building active match order ID index: %w", err)
+		}
+
+		nOrds := uint64(archivedOB.Stats().BucketN - 1 /* BucketN includes top bucket */)
+		if nOrds <= archiveSizeLimit {
+			return nil
+		}
+
+		toClear := int(nOrds - archiveSizeLimit)
+
+		type orderStamp struct {
+			oid   []byte
+			stamp uint64
+		}
+		deletes := make([]*orderStamp, 0, toClear)
+		sortDeletes := func() {
+			sort.Slice(deletes, func(i, j int) bool {
+				return deletes[i].stamp < deletes[j].stamp
+			})
+		}
+		if err := archivedOB.ForEach(func(oidB, v []byte) error {
+			var oid order.OrderID
+			copy(oid[:], oidB)
+			if _, found := oidsWithActiveMatches[oid]; found {
+				return nil
+			}
+			oBkt := archivedOB.Bucket(oidB)
+			if oBkt == nil {
+				return fmt.Errorf("no order bucket iterated order %x", oidB)
+			}
+			stampB := oBkt.Get(updateTimeKey)
+			if stampB == nil {
+				// Highly improbable.
+				stampB = make([]byte, 8)
+			}
+			stamp := intCoder.Uint64(stampB)
+			if len(deletes) < toClear {
+				deletes = append(deletes, &orderStamp{
+					stamp: stamp,
+					oid:   oidB,
+				})
+				sortDeletes()
+				return nil
+			}
+			if stamp > deletes[len(deletes)-1].stamp {
+				return nil
+			}
+			deletes[len(deletes)-1] = &orderStamp{
+				stamp: stamp,
+				oid:   oidB,
+			}
+			sortDeletes()
+			return nil
+		}); err != nil {
+			return fmt.Errorf("archive iteration error: %v", err)
+		}
+
+		deletedOrders := make(map[order.OrderID]struct{})
+		for _, del := range deletes {
+			var oid order.OrderID
+			copy(oid[:], del.oid)
+			deletedOrders[oid] = struct{}{}
+			if err := archivedOB.DeleteBucket(del.oid); err != nil {
+				return fmt.Errorf("error deleting archived order %q: %v", del.oid, err)
+			}
+		}
+
+		matchesToDelete := make([][]byte, 0, archiveSizeLimit /* just avoid some allocs if we can */)
+		archivedMatches := tx.Bucket(archivedMatchesBucket)
+		if archivedMatches == nil {
+			return errors.New("no archived match bucket")
+		}
+		if err := archivedMatches.ForEach(func(k, _ []byte) error {
+			matchBkt := archivedMatches.Bucket(k)
+			if matchBkt == nil {
+				return fmt.Errorf("no bucket found for %x during iteration", k)
+			}
+			var oid order.OrderID
+			copy(oid[:], matchBkt.Get(orderIDKey))
+			if _, found := deletedOrders[oid]; found {
+				matchesToDelete = append(matchesToDelete, k)
+			}
+			return nil
+		}); err != nil {
+			return fmt.Errorf("error finding matches to prune: %w", err)
+		}
+		for i := range matchesToDelete {
+			if err := archivedMatches.DeleteBucket(matchesToDelete[i]); err != nil {
+				return fmt.Errorf("error deleting pruned match %x: %w", matchesToDelete[i], err)
+			}
+		}
+		return nil
+	})
+}
+
 // validateCreds checks that the PrimaryCredentials fields are properly
 // populated.
 func validateCreds(creds *dexdb.PrimaryCredentials) error {