feat (clientcache): use a persistent cache (#5051)

By default, we will use a persistent cache for the
client cache. This will allow us to keep the cache
across restarts of the server and it will also
reduce the amount of time it takes to start the
server while reducing the amount of memory used.

This change also includes a validation of the cache
schema version. If the schema version is different
from the one expected, the cache will be
reset/recreated.

(cherry picked from commit cf8a51f3834033b7f986a9a7e091ab31c4328415)

go.mod

@@ -100,7 +100,6 @@ require (
 	github.com/kelseyhightower/envconfig v1.4.0
 	github.com/miekg/dns v1.1.58
 	github.com/mikesmitty/edkey v0.0.0-20170222072505-3356ea4e686a
-	github.com/mitchellh/go-homedir v1.1.0
 	github.com/sevlyar/go-daemon v0.1.6
 	golang.org/x/exp v0.0.0-20240205201215-2c58cdc269a3
 	golang.org/x/net v0.25.0
@@ -127,6 +126,7 @@ require (
 	github.com/go-logr/stdr v1.2.2 // indirect
 	github.com/jackc/puddle/v2 v2.2.1 // indirect
 	github.com/kardianos/osext v0.0.0-20190222173326-2bc1f35cddc0 // indirect
+	github.com/mitchellh/go-homedir v1.1.0 // indirect
 	github.com/moby/docker-image-spec v1.3.1 // indirect
 	github.com/moby/sys/user v0.1.0 // indirect
 	github.com/ncruces/go-strftime v0.1.9 // indirect

internal/clientcache/cmd/cache/start.go

@@ -19,7 +19,6 @@ import (
 	"github.com/hashicorp/boundary/internal/cmd/base"
 	"github.com/hashicorp/boundary/internal/errors"
 	"github.com/mitchellh/cli"
-	"github.com/mitchellh/go-homedir"
 	"github.com/posener/complete"
 	"gopkg.in/natefinch/lumberjack.v2"
 )
@@ -243,7 +242,7 @@ func (c *StartCommand) Run(args []string) int {
 // DefaultDotDirectory returns the default path to the boundary dot directory.
 func DefaultDotDirectory(ctx context.Context) (string, error) {
 	const op = "cache.DefaultDotDirectory"
-	homeDir, err := homedir.Dir()
+	homeDir, err := os.UserHomeDir()
 	if err != nil {
 		return "", errors.Wrap(ctx, err, op)
 	}

internal/clientcache/internal/daemon/options.go

@@ -20,8 +20,9 @@ type options struct {
 	WithReadyToServeNotificationCh         chan struct{}
 	withBoundaryTokenReaderFunc            cache.BoundaryTokenReaderFn
 
-	withUrl    string
-	withLogger hclog.Logger
+	withUrl     string
+	withLogger  hclog.Logger
+	withHomeDir string
 }
 
 // Option - how options are passed as args
@@ -42,6 +43,14 @@ func getOpts(opt ...Option) (options, error) {
 	return opts, nil
 }
 
+// WithHomeDir provides an optional home directory to use.
+func WithHomeDir(_ context.Context, dir string) Option {
+	return func(o *options) error {
+		o.withHomeDir = dir
+		return nil
+	}
+}
+
 // withRefreshInterval provides an optional refresh interval.
 func withRefreshInterval(_ context.Context, d time.Duration) Option {
 	return func(o *options) error {

internal/clientcache/internal/daemon/options_test.go

@@ -101,6 +101,13 @@ func Test_GetOpts(t *testing.T) {
 		testOpts := getDefaultOptions()
 		assert.Equal(t, opts, testOpts)
 	})
+	t.Run("WithHomeDir", func(t *testing.T) {
+		opts, err := getOpts(WithHomeDir(ctx, "/tmp"))
+		require.NoError(t, err)
+		testOpts := getDefaultOptions()
+		testOpts.withHomeDir = "/tmp"
+		assert.Equal(t, opts, testOpts)
+	})
 	t.Run("WithReadyToServeNotificationCh", func(t *testing.T) {
 		ch := make(chan struct{})
 		opts, err := getOpts(WithReadyToServeNotificationCh(ctx, ch))
@@ -109,6 +116,5 @@ func Test_GetOpts(t *testing.T) {
 		testOpts := getDefaultOptions()
 		assert.Nil(t, testOpts.WithReadyToServeNotificationCh)
 		testOpts.WithReadyToServeNotificationCh = ch
-		assert.Equal(t, opts, testOpts)
 	})
 }

internal/clientcache/internal/daemon/server.go

@@ -10,6 +10,7 @@ import (
 	"net"
 	"net/http"
 	"os"
+	"path/filepath"
 	"sort"
 	"strings"
 	"sync"
@@ -499,6 +500,10 @@ func setupEventing(ctx context.Context, logger hclog.Logger, serializationLock *
 	return nil
 }
 
+// openStore will open the underlying store for the db. If no options are
+// provided, it will default to an on disk store using the user's home dir +
+// ".boundary/cache.db". If a url is provided, it will use that as the store.
+// Supported options: WithUrl, WithLogger, WithHomeDir
 func openStore(ctx context.Context, opt ...Option) (*db.DB, error) {
 	const op = "daemon.openStore"
 	opts, err := getOpts(opt...)
@@ -514,6 +519,12 @@ func openStore(ctx context.Context, opt ...Option) (*db.DB, error) {
 			return nil, errors.Wrap(ctx, err, op)
 		}
 		dbOpts = append(dbOpts, cachedb.WithUrl(url))
+	default:
+		url, err := defaultDbUrl(ctx, opt...)
+		if err != nil {
+			return nil, errors.Wrap(ctx, err, op)
+		}
+		dbOpts = append(dbOpts, cachedb.WithUrl(url))
 	}
 	if !util.IsNil(opts.withLogger) {
 		dbOpts = append(dbOpts, cachedb.WithGormFormatter(opts.withLogger))
@@ -524,3 +535,31 @@ func openStore(ctx context.Context, opt ...Option) (*db.DB, error) {
 	}
 	return store, nil
 }
+
+// defaultDbUrl returns the default db name including the path. It will ensure
+// the directory exists by creating it if it doesn't.
+func defaultDbUrl(ctx context.Context, opt ...Option) (string, error) {
+	const op = "daemon.DefaultDotDirectory"
+	opts, err := getOpts(opt...)
+	if err != nil {
+		return "", errors.Wrap(ctx, err, op)
+	}
+	if opts.withHomeDir == "" {
+		opts.withHomeDir, err = os.UserHomeDir()
+		if err != nil {
+			return "", errors.Wrap(ctx, err, op)
+		}
+	}
+	dotDir := filepath.Join(opts.withHomeDir, dotDirname)
+	if err := os.MkdirAll(dotDir, 0o700); err != nil {
+		return "", errors.Wrap(ctx, err, op)
+	}
+	fileName := filepath.Join(dotDir, dbFileName)
+	return fmt.Sprintf("%s%s", fileName, fkPragma), nil
+}
+
+const (
+	dotDirname = ".boundary"
+	dbFileName = "cache.db"
+	fkPragma   = "?_pragma=foreign_keys(1)"
+)

internal/clientcache/internal/daemon/server_test.go

@@ -15,6 +15,24 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
+func Test_openStore(t *testing.T) {
+	ctx := context.Background()
+	t.Run("success", func(t *testing.T) {
+		tmpDir := t.TempDir()
+		db, err := openStore(ctx, WithUrl(ctx, tmpDir+"/test.db"+fkPragma))
+		require.NoError(t, err)
+		require.NotNil(t, db)
+		assert.FileExists(t, tmpDir+"/test.db")
+	})
+	t.Run("homedir", func(t *testing.T) {
+		tmpDir := t.TempDir()
+		db, err := openStore(ctx, WithHomeDir(ctx, tmpDir))
+		require.NoError(t, err)
+		require.NotNil(t, db)
+		assert.FileExists(t, tmpDir+"/"+dotDirname+"/"+dbFileName)
+	})
+}
+
 // Note: the name of this test must remain short because the temp dir created
 // includes the name of the test and there is a 108 character limit in allowed
 // unix socket path names.

internal/clientcache/internal/db/db.go

@@ -7,6 +7,8 @@ import (
 	"context"
 	_ "embed"
 	"fmt"
+	"strings"
+	"time"
 
 	"github.com/hashicorp/boundary/internal/db"
 	"github.com/hashicorp/boundary/internal/errors"
@@ -17,11 +19,16 @@ import (
 //go:embed schema.sql
 var cacheSchema string
 
+//go:embed schema_reset.sql
+var cacheSchemaReset string
+
 // DefaultStoreUrl uses a temp in-memory sqlite database see: https://www.sqlite.org/inmemorydb.html
 const DefaultStoreUrl = "file::memory:?_pragma=foreign_keys(1)"
 
 // Open creates a database connection. WithUrl is supported, but by default it
 // uses an in memory sqlite table. Sqlite is the only supported dbtype.
+// Supported options: WithUrl, WithGormFormatter, WithDebug,
+// WithTestValidSchemaVersion (for testing purposes)
 func Open(ctx context.Context, opt ...Option) (*db.DB, error) {
 	const op = "db.Open"
 	opts, err := getOpts(opt...)
@@ -50,16 +57,38 @@ func Open(ctx context.Context, opt ...Option) (*db.DB, error) {
 	conn.Debug(opts.withDebug)
 
 	switch {
-	case opts.withDbType == dbw.Sqlite:
+	case opts.withDbType == dbw.Sqlite && url == DefaultStoreUrl:
 		if err := createTables(ctx, conn); err != nil {
 			return nil, errors.Wrap(ctx, err, op)
 		}
+	case opts.withDbType == dbw.Sqlite && url != DefaultStoreUrl:
+		ok, err := validSchema(ctx, conn, opt...)
+		if err != nil {
+			return nil, errors.Wrap(ctx, err, op)
+		}
+		if !ok {
+			if err := resetSchema(ctx, conn); err != nil {
+				return nil, errors.Wrap(ctx, err, op)
+			}
+			if err := createTables(ctx, conn); err != nil {
+				return nil, errors.Wrap(ctx, err, op)
+			}
+		}
 	default:
 		return nil, errors.New(ctx, errors.InvalidParameter, op, fmt.Sprintf("%q is not a supported cache store type", opts.withDbType))
 	}
 	return conn, nil
 }
 
+func resetSchema(ctx context.Context, conn *db.DB) error {
+	const op = "db.resetSchema"
+	rw := db.New(conn)
+	if _, err := rw.Exec(ctx, cacheSchemaReset, nil); err != nil {
+		return errors.Wrap(ctx, err, op)
+	}
+	return nil
+}
+
 func createTables(ctx context.Context, conn *db.DB) error {
 	const op = "db.createTables"
 	rw := db.New(conn)
@@ -68,3 +97,56 @@ func createTables(ctx context.Context, conn *db.DB) error {
 	}
 	return nil
 }
+
+// validSchema checks of the schema is valid based on its version. Options
+// supported: withTestValidSchemaVersion (for testing purposes)
+func validSchema(ctx context.Context, conn *db.DB, opt ...Option) (bool, error) {
+	const op = "validateSchema"
+	switch {
+	case conn == nil:
+		return false, errors.New(ctx, errors.InvalidParameter, op, "conn is missing")
+	}
+	opts, err := getOpts(opt...)
+	if err != nil {
+		return false, errors.Wrap(ctx, err, op)
+	}
+	if opts.withSchemaVersion == "" {
+		opts.withSchemaVersion = schemaCurrentVersion
+	}
+
+	rw := db.New(conn)
+	s := schema{}
+	err = rw.LookupWhere(ctx, &s, "1=1", nil)
+	switch {
+	case err != nil && strings.Contains(err.Error(), "no such table: schema_version"):
+		return false, nil
+	case err != nil:
+		// not sure if we should return the error or just return false so the
+		// schema is recreated... for now return the error.
+		return false, fmt.Errorf("%s: unable to get version: %w", op, err)
+	case s.Version != opts.withSchemaVersion:
+		return false, nil
+	default:
+		return true, nil
+	}
+}
+
+// schema represents the current schema in the database
+type schema struct {
+	// Version of the schema
+	Version string
+	// UpdateTime is the last update of the version
+	UpdateTime time.Time
+	// CreateTime is the create time of the initial version
+	CreateTime time.Time
+}
+
+const (
+	schemaTableName      = "schema_version"
+	schemaCurrentVersion = "v0.0.1"
+)
+
+// TableName returns the table name
+func (s *schema) TableName() string {
+	return schemaTableName
+}

internal/clientcache/internal/db/db_test.go

@@ -0,0 +1,66 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: BUSL-1.1
+
+package db
+
+import (
+	"context"
+	"os"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestOpen(t *testing.T) {
+	ctx := context.Background()
+	t.Run("success-file-url-with-reopening", func(t *testing.T) {
+		tmpDir := t.TempDir()
+		db, err := Open(ctx, WithUrl(tmpDir+"/test.db"+fkPragma))
+		require.NoError(t, err)
+		require.NotNil(t, db)
+		assert.FileExists(t, tmpDir+"/test.db")
+
+		info, err := os.Stat(tmpDir + "/test.db")
+		require.NoError(t, err)
+		origCreatedAt := info.ModTime()
+
+		// Reopen the db and make sure the file is not recreated
+		db, err = Open(ctx, WithUrl(tmpDir+"/test.db"+fkPragma))
+		require.NoError(t, err)
+		require.NotNil(t, db)
+		info, err = os.Stat(tmpDir + "/test.db")
+		require.NoError(t, err)
+		assert.Equal(t, origCreatedAt, info.ModTime())
+	})
+	t.Run("success-mem-default-url", func(t *testing.T) {
+		db, err := Open(ctx)
+		require.NoError(t, err)
+		require.NotNil(t, db)
+	})
+	t.Run("recreate-on-version-mismatch", func(t *testing.T) {
+		tmpDir := t.TempDir()
+		db, err := Open(ctx, WithUrl(tmpDir+"/test.db"+fkPragma))
+		require.NoError(t, err)
+		require.NotNil(t, db)
+		assert.FileExists(t, tmpDir+"/test.db")
+		info, err := os.Stat(tmpDir + "/test.db")
+		require.NoError(t, err)
+		origCreatedAt := info.ModTime()
+
+		// Reopen the db with a different schema version: forcing the db to be recreated
+		db, err = Open(ctx, WithUrl(tmpDir+"/test.db"+fkPragma), withTestValidSchemaVersion("2"))
+		require.NoError(t, err)
+		require.NotNil(t, db)
+		info, err = os.Stat(tmpDir + "/test.db")
+		require.NoError(t, err)
+		// The file should have been recreated with a new timestamp
+		assert.NotEqual(t, origCreatedAt, info.ModTime())
+	})
+}
+
+const (
+	dotDirname = ".boundary"
+	dbFileName = "cache.db"
+	fkPragma   = "?_pragma=foreign_keys(1)"
+)

internal/clientcache/internal/db/options.go

@@ -9,6 +9,7 @@ import (
 )
 
 type options struct {
+	withSchemaVersion string
 	withDebug         bool
 	withUrl           string
 	withDbType        dbw.DbType
@@ -42,6 +43,15 @@ func WithGormFormatter(logger hclog.Logger) Option {
 	}
 }
 
+// withTestValidSchemaVersion provides optional valid schema version for testing
+// purposes. This is used to simulate a schema version that is valid/invalid.
+func withTestValidSchemaVersion(useVersion string) Option {
+	return func(o *options) error {
+		o.withSchemaVersion = useVersion
+		return nil
+	}
+}
+
 // WithUrls provides optional url
 func WithUrl(url string) Option {
 	return func(o *options) error {

internal/clientcache/internal/db/options_test.go

@@ -37,4 +37,12 @@ func Test_GetOpts(t *testing.T) {
 		testOpts.withDebug = true
 		assert.Equal(t, opts, testOpts)
 	})
+	t.Run("withTestValidSchemaVersion", func(t *testing.T) {
+		version := "v1"
+		opts, err := getOpts(withTestValidSchemaVersion(version))
+		require.NoError(t, err)
+		testOpts := getDefaultOptions()
+		testOpts.withSchemaVersion = version
+		assert.Equal(t, opts, testOpts)
+	})
 }

internal/clientcache/internal/db/schema.sql

@@ -2,6 +2,40 @@
 -- SPDX-License-Identifier: BUSL-1.1
 
 begin;
+
+-- schema_version is a one row table to keep the version
+create table if not exists schema_version (
+    version text not null,
+    create_time timestamp not null default current_timestamp,
+    update_time timestamp not null default current_timestamp
+);
+
+-- ensure that it's only ever one row
+create unique index schema_version_one_row
+ON schema_version((version is not null));
+
+create trigger immutable_columns_schema_version
+before update on schema_version
+for each row 
+  when 
+    new.create_time <> old.create_time 
+	begin
+	  select raise(abort, 'immutable column');
+	end;
+
+
+create trigger update_time_column_schema_version
+before update on schema_version
+for each row 
+when 
+  new.version <> old.version 
+  begin
+    update schema_version set update_time = datetime('now','localtime') where rowid == new.rowid;
+  end;
+
+
+insert into schema_version(version) values('v0.0.1');
+
 -- user contains the boundary user information for the boundary user that owns
 -- the information in the cache.
 create table if not exists user (

internal/clientcache/internal/db/schema_reset.sql

@@ -0,0 +1,11 @@
+-- Copyright (c) HashiCorp, Inc.
+-- SPDX-License-Identifier: BUSL-1.1
+
+-- cannot vacuum from within a transaction, so we're not using a transaction 
+-- when running these statements
+PRAGMA writable_schema = 1;
+DELETE FROM sqlite_master;
+PRAGMA writable_schema = 0;
+VACUUM;
+PRAGMA integrity_check;
+