Init

app/db/backup_engine.py

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+import time
+from abc import ABC, abstractmethod
+import gzip
+import subprocess
+import uuid
+from typing import Any
+
+from .models import DB, DBBackup
+# https://medium.com/poka-techblog/5-different-ways-to-backup-your-postgresql-database-using-python-3f06cea4f51
+
+
+class BackupEngineBase(ABC):
+    def __init__(self, backupdb: DBBackup):
+        self.backup_instance = backupdb
+        self.db_instance = self.backup_instance.db
+
+        # self.db_instance = db_instance
+        # self.backup_instance = BackupDB.objects.create(
+        #     db=self.db_instance,
+        #     rel_path="{db_id}-{timestamp}-{rand_gen}.{db_type}.{ext}".format(
+        #         db_id=self.db_instance.id,
+        #         timestamp=int(time.time()),
+        #         rand_gen=uuid.uuid4().hex[:5],
+        #         db_type=self.db_instance.db_type,
+        #         ext='sql.gz' if self.gzip else 'sql'
+        #     ),
+        # )
+        self.credentials = {"database": self.db_instance.db_name, **self.db_instance.credential.credentials}
+
+    @property
+    @abstractmethod
+    def cmd_kwargs(self) -> dict[str, Any]:
+        ...
+
+    @property
+    def format_cmd_kwargs(self):
+        return " ".join([
+            key if isinstance(value, bool) else f"{key} {value}"
+            for key, value in self.cmd_kwargs.items()
+            if value
+        ])
+
+    @property
+    @abstractmethod
+    def cmd(self):
+        ...
+
+    @property
+    def cmd_format(self):
+        return self.cmd.format(cmd_kwargs=self.format_cmd_kwargs, **self.credentials)
+
+    def popen(self):
+        return subprocess.Popen(self.cmd_format,
+                                stdout=subprocess.PIPE,
+                                stderr=subprocess.STDOUT,
+                                shell=True,
+                                universal_newlines=True)
+
+    def file_obj(self, path):
+        return gzip.open(path, "wb")
+
+    def run(self, task_id=None):
+        self.backup_instance.update_task_id(task_id)
+        try:
+            with self.file_obj(self.backup_instance.abs_path) as f:
+                with self.popen() as proc:
+                    self.backup_instance.update_status("running")
+                    for line in iter(proc.stdout.readline, ""):
+                        f.write(line.encode())
+        except Exception as e:
+            self.backup_instance.update_status("finished")
+            raise e
+
+
+class MySQLBackupEngine(BackupEngineBase):
+    @property
+    def cmd_kwargs(self) -> dict[str, Any]:
+        return {
+            "--no-tablespaces": True
+        }
+
+    @property
+    def cmd(self):
+        return "mysqldump {cmd_kwargs} -h {host} -P {port} -u {user} -p{password} {database}"
+
+
+class PostgreSQLBackupEngine(BackupEngineBase):
+    @property
+    def cmd_kwargs(self) -> dict[str, Any]:
+        return {
+            "--no-owner": True,
+            "--no-privileges": True,
+            "--clean": False
+        }
+
+    @property
+    def cmd(self):
+        return "pg_dump {cmd_kwargs} --dbname=postgresql://{user}:{password}@{host}:{port}/{database}"