feat(pg_dump): Add '--if-exists' option for pg_dump (#478)

dbbackup/db/postgresql.py

@@ -116,6 +116,7 @@ class PgDumpBinaryConnector(PgDumpConnector):
     restore_cmd = "pg_restore"
     single_transaction = True
     drop = True
+    if_exists = False
 
     def _create_dump(self):
         cmd = f"{self.dump_cmd} "
@@ -145,6 +146,9 @@ def _restore_dump(self, dump):
         if self.schemas:
             cmd += " -n " + " -n ".join(self.schemas)
 
+        if self.if_exists:
+            cmd += " --if-exists"
+
         cmd = f"{self.restore_prefix} {cmd} {self.restore_suffix}"
         stdout, stderr = self.run_command(cmd, stdin=dump, env=self.restore_env)
         return stdout, stderr

docs/changelog.rst

@@ -7,6 +7,7 @@ Unreleased
 * Add PostgreSQL Schema support by @angryfoxx in https://github.com/jazzband/django-dbbackup/pull/507
 * Fix restore of database from S3 storage by reintroducing inputfile.seek(0) to utils.uncompress_file
 * Fix bug where dbbackup management command would not respect settings.py:DBBACKUP_DATABASES
+* Add option `--if-exists` for pg_dump command
 
 4.1.0 (2024-01-14)
 ------------------

docs/databases.rst

@@ -166,6 +166,13 @@ This corresponds to ``--clean`` argument of ``pg_dump`` and ``pg_restore``.
 
 Default: ``True``
 
+IF_EXISTS
+~~~~
+
+Use DROP ... IF EXISTS commands to drop objects in ``--clean`` mode of ``pg_dump``.
+
+Default: ``False``
+
 PostGIS
 -------