feature(backups): caps for autobackups

selfprivacy_api/backup/__init__.py

@@ -283,7 +283,10 @@ class Backups:
                 service_name,
                 reason=reason,
             )
+
             Backups._store_last_snapshot(service_name, snapshot)
+            if reason == BackupReason.AUTO:
+                Backups._prune_auto_snaps(service)
             service.post_restore()
         except Exception as error:
             Jobs.update(job, status=JobStatus.ERROR)
@@ -292,6 +295,40 @@ class Backups:
         Jobs.update(job, status=JobStatus.FINISHED)
         return snapshot
 
+    @staticmethod
+    def _auto_snaps(service):
+        return [
+            snap
+            for snap in Backups.get_snapshots(service)
+            if snap.reason == BackupReason.AUTO
+        ]
+
+    @staticmethod
+    def _prune_auto_snaps(service) -> None:
+        max = Backups.max_auto_snapshots()
+        if max == -1:
+            return
+
+        auto_snaps = Backups._auto_snaps(service)
+        if len(auto_snaps) > max:
+            n_to_kill = len(auto_snaps) - max
+            sorted_snaps = sorted(auto_snaps, key=lambda s: s.created_at)
+            snaps_to_kill = sorted_snaps[:n_to_kill]
+            for snap in snaps_to_kill:
+                Backups.forget_snapshot(snap)
+
+    @staticmethod
+    def set_max_auto_snapshots(value: int) -> None:
+        """everything <=0 means unlimited"""
+        if value <= 0:
+            value = -1
+        Storage.set_max_auto_snapshots(value)
+
+    @staticmethod
+    def max_auto_snapshots() -> int:
+        """-1 means unlimited"""
+        return Storage.max_auto_snapshots()
+
     # Restoring
 
     @staticmethod

selfprivacy_api/backup/storage.py

@@ -26,6 +26,7 @@ REDIS_INITTED_CACHE = "backups:repo_initted"
 REDIS_PROVIDER_KEY = "backups:provider"
 REDIS_AUTOBACKUP_PERIOD_KEY = "backups:autobackup_period"
 
+REDIS_AUTOBACKUP_MAX_KEY = "backups:autobackup_cap"
 
 redis = RedisPool().get_connection()
 
@@ -39,6 +40,7 @@ class Storage:
         redis.delete(REDIS_PROVIDER_KEY)
         redis.delete(REDIS_AUTOBACKUP_PERIOD_KEY)
         redis.delete(REDIS_INITTED_CACHE)
+        redis.delete(REDIS_AUTOBACKUP_MAX_KEY)
 
         prefixes_to_clean = [
             REDIS_SNAPSHOTS_PREFIX,
@@ -175,3 +177,14 @@ class Storage:
     def mark_as_uninitted():
         """Marks the repository as initialized"""
         redis.delete(REDIS_INITTED_CACHE)
+
+    @staticmethod
+    def set_max_auto_snapshots(value: int):
+        redis.set(REDIS_AUTOBACKUP_MAX_KEY, value)
+
+    @staticmethod
+    def max_auto_snapshots():
+        if redis.exists(REDIS_AUTOBACKUP_MAX_KEY):
+            return int(redis.get(REDIS_AUTOBACKUP_MAX_KEY))
+        else:
+            return -1

tests/test_graphql/test_backup.py

@@ -298,6 +298,31 @@ def test_backup_reasons(backups, dummy_service):
     assert snaps[0].reason == BackupReason.AUTO
 
 
+def test_too_many_auto(backups, dummy_service):
+    assert Backups.max_auto_snapshots() == -1
+    Backups.set_max_auto_snapshots(2)
+    assert Backups.max_auto_snapshots() == 2
+
+    snap = Backups.back_up(dummy_service, BackupReason.AUTO)
+    assert len(Backups.get_snapshots(dummy_service)) == 1
+    snap2 = Backups.back_up(dummy_service, BackupReason.AUTO)
+    assert len(Backups.get_snapshots(dummy_service)) == 2
+    snap3 = Backups.back_up(dummy_service, BackupReason.AUTO)
+    assert len(Backups.get_snapshots(dummy_service)) == 2
+
+    snaps = Backups.get_snapshots(dummy_service)
+
+    assert snap2 in snaps
+    assert snap3 in snaps
+    assert snap not in snaps
+
+    Backups.set_max_auto_snapshots(-1)
+    snap4 = Backups.back_up(dummy_service, BackupReason.AUTO)
+    snaps = Backups.get_snapshots(dummy_service)
+    assert len(snaps) == 3
+    assert snap4 in snaps
+
+
 def folder_files(folder):
     return [
         path.join(folder, filename)