From 0a63e1f593df09bbb1d3a6c9b30c900505385d00 Mon Sep 17 00:00:00 2001
From: Julien Dessaux <julien.dessaux@adyxax.org>
Date: Thu, 1 May 2025 14:27:49 +0200
Subject: [PATCH] feat(backend): add age condition for state versions retention

Closes #59
---
 cmd/tfstated/main_test.go |  2 ++
 pkg/database/db.go        | 28 ++++++++++++++++++----------
 pkg/database/states.go    | 22 ++++++++++++----------
 3 files changed, 32 insertions(+), 20 deletions(-)

diff --git a/cmd/tfstated/main_test.go b/cmd/tfstated/main_test.go
index ecb82ee..dd17871 100644
--- a/cmd/tfstated/main_test.go
+++ b/cmd/tfstated/main_test.go
@@ -36,6 +36,8 @@ func TestMain(m *testing.M) {
 			return "a528D1m9q3IZxLinSmHmeKxrx3Pmm7GQ3nBzIDxjr0A="
 		case "TFSTATED_VERSIONS_HISTORY_LIMIT":
 			return "3"
+		case "TFSTATED_VERSIONS_HISTORY_MINIMUM_DAYS":
+			return "0"
 		default:
 			return ""
 		}
diff --git a/pkg/database/db.go b/pkg/database/db.go
index 09d9d19..2c3c908 100644
--- a/pkg/database/db.go
+++ b/pkg/database/db.go
@@ -28,12 +28,13 @@ func initDB(ctx context.Context, url string) (*sql.DB, error) {
 }
 
 type DB struct {
-	ctx                  context.Context
-	dataEncryptionKey    scrypto.AES256Key
-	readDB               *sql.DB
-	sessionsSalt         scrypto.AES256Key
-	versionsHistoryLimit int
-	writeDB              *sql.DB
+	ctx                        context.Context
+	dataEncryptionKey          scrypto.AES256Key
+	readDB                     *sql.DB
+	sessionsSalt               scrypto.AES256Key
+	versionsHistoryLimit       int
+	versionsHistoryMinimumDays int
+	writeDB                    *sql.DB
 }
 
 func NewDB(ctx context.Context, url string, getenv func(string) string) (*DB, error) {
@@ -60,10 +61,11 @@ func NewDB(ctx context.Context, url string, getenv func(string) string) (*DB, er
 	writeDB.SetMaxOpenConns(1)
 
 	db := DB{
-		ctx:                  ctx,
-		readDB:               readDB,
-		versionsHistoryLimit: 64,
-		writeDB:              writeDB,
+		ctx:                        ctx,
+		readDB:                     readDB,
+		versionsHistoryLimit:       128,
+		versionsHistoryMinimumDays: 28,
+		writeDB:                    writeDB,
 	}
 	pragmas := []struct {
 		key   string
@@ -103,6 +105,12 @@ func NewDB(ctx context.Context, url string, getenv func(string) string) (*DB, er
 			return nil, fmt.Errorf("failed to parse the TFSTATED_VERSIONS_HISTORY_LIMIT environment variable, expected an integer: %w", err)
 		}
 	}
+	versionsHistoryMinimumDays := getenv("TFSTATED_VERSIONS_HISTORY_MINIMUM_DAYS")
+	if versionsHistoryMinimumDays != "" {
+		if db.versionsHistoryMinimumDays, err = strconv.Atoi(versionsHistoryMinimumDays); err != nil {
+			return nil, fmt.Errorf("failed to parse the TFSTATED_VERSIONS_HISTORY_MINIMUM_DAYS environment variable, expected an integer: %w", err)
+		}
+	}
 
 	return &db, nil
 }
diff --git a/pkg/database/states.go b/pkg/database/states.go
index 0bc6d17..3429418 100644
--- a/pkg/database/states.go
+++ b/pkg/database/states.go
@@ -244,19 +244,21 @@ func (db *DB) SetState(path string, accountId uuid.UUID, data []byte, lock strin
 		if err != nil {
 			return fmt.Errorf("failed to touch updated for state: %w", err)
 		}
+		min := time.Now().Add(time.Duration(db.versionsHistoryMinimumDays) * -24 * time.Hour)
 		_, err = tx.ExecContext(db.ctx,
 			`DELETE FROM versions
-           WHERE state_id = (SELECT id
-                               FROM states
-                               WHERE path = :path)
-             AND id < (SELECT MIN(id)
-                         FROM(SELECT versions.id
-                                FROM versions
-                                JOIN states ON states.id = versions.state_id
-                                WHERE states.path = :path
-                                ORDER BY versions.id DESC
-                                LIMIT :limit));`,
+               WHERE state_id = (SELECT id
+                                   FROM states
+                                   WHERE path = :path)
+               AND id < (SELECT MIN(id)
+                           FROM(SELECT versions.id
+                                  FROM versions
+                                  JOIN states ON states.id = versions.state_id
+                                  WHERE states.path = :path AND versions.created < :min
+                                  ORDER BY versions.id DESC
+                                  LIMIT :limit));`,
 			sql.Named("limit", db.versionsHistoryLimit),
+			sql.Named("min", min),
 			sql.Named("path", path),
 		)
 		return err