feat: sqlserver-dacpac-backup

engines/mssql.py

@@ -2,6 +2,7 @@
 
 from typing import Any
 
+from core.fields import Field
 from core.specs import DatabaseSpec
 from core.utils import generate_password
 from engines.base import StandardSqlEngine
@@ -12,6 +13,24 @@ class MssqlEngine(StandardSqlEngine):
     key, display, default_port = "mssql", "Microsoft SQL Server", 1433
     template, slug, db_prefix = "engines/mssql.yml.j2", "mssql", "master"
 
+    def option_fields(self) -> list[Field]:
+        return [
+            Field(
+                "backup_format",
+                "Backup format",
+                "choice",
+                default="dacpac",
+                choices=("dacpac", "bacpac"),
+                help=(
+                    "dacpac: sqlpackage Extract with all table data (default, works "
+                    "with Windows principals). bacpac: sqlpackage Export, validated "
+                    "against Azure SQL rules; fails with SQL71627 on databases holding "
+                    "Windows principals such as NT AUTHORITY\\SYSTEM. Requires agent "
+                    "1.22.0 or later."
+                ),
+            ),
+        ]
+
     def generate(
         self, *, auth: bool, ports: PortAllocator, answers: dict[str, Any]
     ) -> DatabaseSpec:

tests/engines/mssql.py

@@ -70,7 +70,10 @@ def fields():
         ("password", "secret", None),
     ]
     assert MSSQL.fields_new() == []
-    assert MSSQL.option_fields() == []
+    assert field_specs(MSSQL.option_fields()) == [
+        ("backup_format", "choice", "dacpac"),
+    ]
+    assert MSSQL.option_fields()[0].choices == ("dacpac", "bacpac")
 
 
 def from_existing():
@@ -115,6 +118,10 @@ def compose_service_inline(render_engine):
     ]
 
 
-def options_are_ignored(ports):
-    spec = MSSQL.generate(auth=True, ports=ports, answers={"options": {"x": 1}})
-    assert spec.options == {}
+def only_non_default_options_reach_the_agent(ports):
+    spec = MSSQL.generate(auth=True, ports=ports, answers={})
+    bacpac = spec.with_options({"backup_format": "bacpac", "unknown": 1})
+    assert MSSQL.non_default_options(bacpac) == {"backup_format": "bacpac"}
+    assert MSSQL.agent_entry(bacpac)["options"] == {"backup_format": "bacpac"}
+    dacpac = spec.with_options({"backup_format": "dacpac"})
+    assert "options" not in MSSQL.agent_entry(dacpac)