Remove stale session directories

coder · mtojek · Sep 11, 2023 · Sep 5, 2023 · Sep 6, 2023 · Sep 6, 2023
commit afb0982d2ebca2bcf066b2defd0c27a014e65a7c
diff --git a/go.mod b/go.mod
@@ -196,7 +196,10 @@ require (
 	tailscale.com v1.46.1
 )
 
-require gopkg.in/DataDog/dd-trace-go.v1 v1.54.0
+require (
+	github.com/djherbis/atime v1.1.0
+	gopkg.in/DataDog/dd-trace-go.v1 v1.54.0
+)
 
 require (
 	cloud.google.com/go/compute v1.23.0 // indirect

diff --git a/go.sum b/go.sum
@@ -270,6 +270,8 @@ github.com/dgryski/go-farm v0.0.0-20200201041132-a6ae2369ad13 h1:fAjc9m62+UWV/WA
 github.com/dgryski/trifles v0.0.0-20200323201526-dd97f9abfb48 h1:fRzb/w+pyskVMQ+UbP35JkH8yB7MYb4q/qhBarqZE6g=
 github.com/dgryski/trifles v0.0.0-20200323201526-dd97f9abfb48/go.mod h1:if7Fbed8SFyPtHLHbg49SI7NAdJiC5WIA09pe59rfAA=
 github.com/dhui/dktest v0.3.16 h1:i6gq2YQEtcrjKbeJpBkWjE8MmLZPYllcjOFbTZuPDnw=
+github.com/djherbis/atime v1.1.0 h1:rgwVbP/5by8BvvjBNrbh64Qz33idKT3pSnMSJsxhi0g=
+github.com/djherbis/atime v1.1.0/go.mod h1:28OF6Y8s3NQWwacXc5eZTsEsiMzp7LF8MbXE+XJPdBE=
 github.com/dlclark/regexp2 v1.7.0 h1:7lJfhqlPssTb1WQx4yvTHN0uElPEv52sbaECrAQxjAo=
 github.com/dlclark/regexp2 v1.7.0/go.mod h1:DHkYz0B9wPfa6wondMfaivmHpzrQ3v9q8cnmRbL6yW8=
 github.com/docker/cli v23.0.5+incompatible h1:ufWmAOuD3Vmr7JP2G5K3cyuNC4YZWiAsuDEvFVVDafE=

diff --git a/provisionersdk/session.go b/provisionersdk/session.go
@@ -11,16 +11,21 @@ import (
 	"strings"
 	"time"
 
+	"github.com/djherbis/atime"
 	"github.com/google/uuid"
 	"golang.org/x/xerrors"
 
 	"cdr.dev/slog"
 	"github.com/coder/coder/v2/provisionersdk/proto"
 )
 
-// ReadmeFile is the location we look for to extract documentation from template
-// versions.
-const ReadmeFile = "README.md"
+const (
+	// ReadmeFile is the location we look for to extract documentation from template versions.
+	ReadmeFile = "README.md"
+
+	sessionDirPrefix          = "Session"
+	staleSessionDaysThreshold = 7 * 24 * time.Hour
+)
 
 // protoServer is a wrapper that translates the dRPC protocol into a Session with method calls into the Server.
 type protoServer struct {
@@ -36,11 +41,13 @@ func (p *protoServer) Session(stream proto.DRPCProvisioner_SessionStream) error
 		server: p.server,
 	}
 
-	// TODO Clean stale sessions in WorkDir
+	err := cleanStaleSessions(s.Context(), p.opts.WorkDirectory, time.Now(), s.Logger)
+	if err != nil {
+		return xerrors.Errorf("clean state sessions %q: %w", s.WorkDirectory, err)
+	}
 
-	sessDir := fmt.Sprintf("Session%s", sessID)
-	s.WorkDirectory = filepath.Join(p.opts.WorkDirectory, sessDir)
-	err := os.MkdirAll(s.WorkDirectory, 0o700)
+	s.WorkDirectory = filepath.Join(p.opts.WorkDirectory, sessionDir(sessID))
+	err = os.MkdirAll(s.WorkDirectory, 0o700)
 	if err != nil {
 		return xerrors.Errorf("create work directory %q: %w", s.WorkDirectory, err)
 	}
@@ -319,3 +326,43 @@ func (r *request[R, C]) do() (C, error) {
 		return c, nil
 	}
 }
+
+func cleanStaleSessions(ctx context.Context, workDirectory string, now time.Time, logger slog.Logger) error {
+	entries, err := os.ReadDir(workDirectory)
+	if err != nil {
+		return xerrors.Errorf("can't read %q directory", workDirectory)
+	}
+
+	for _, entry := range entries {
+		dirName := entry.Name()
+
+		if entry.IsDir() && isValidSessionDir(dirName) {
+			sessionDirPath := filepath.Join(workDirectory, dirName)
+			fi, err := entry.Info()
+			if err != nil {
+				return xerrors.Errorf("can't read %q directory info", sessionDirPath)
+			}
+
+			lastAccessTime := atime.Get(fi)
+			if lastAccessTime.Add(staleSessionDaysThreshold).After(now) {
+				continue
+			}
+
+			logger.Info(ctx, "Remove stale session directory: %s", sessionDirPath)
+			err = os.RemoveAll(sessionDirPath)
+			if err != nil {
+				return xerrors.Errorf("can't remove %q directory", sessionDirPath)
+			}
+		}
+	}
+	return nil
+}
+
+func sessionDir(sessID string) string {
+	return sessionDirPrefix + sessID
+}
+
+func isValidSessionDir(dirName string) bool {
+	match, err := filepath.Match(sessionDirPrefix+"*", dirName)
+	return err == nil && match
+}