Add support for ulimit in addon config (#6206)

* Add support for ulimit in addon config

Similar to docker-compose, this adds support for setting ulimits
for addons via the addon config. This is useful e.g. for InfluxDB
which on its own does not support setting higher open file descriptor
limits, but recommends increasing limits on the host.

* Make soft and hard limit mandatory if ulimit is a dict

tests/addons/test_config.py

@@ -419,3 +419,71 @@ def test_valid_schema():
     config["schema"] = {"field": "invalid"}
     with pytest.raises(vol.Invalid):
         assert vd.SCHEMA_ADDON_CONFIG(config)
+
+
+def test_ulimits_simple_format():
+    """Test ulimits simple format validation."""
+    config = load_json_fixture("basic-addon-config.json")
+
+    config["ulimits"] = {"nofile": 65535, "nproc": 32768, "memlock": 134217728}
+
+    valid_config = vd.SCHEMA_ADDON_CONFIG(config)
+    assert valid_config["ulimits"]["nofile"] == 65535
+    assert valid_config["ulimits"]["nproc"] == 32768
+    assert valid_config["ulimits"]["memlock"] == 134217728
+
+
+def test_ulimits_detailed_format():
+    """Test ulimits detailed format validation."""
+    config = load_json_fixture("basic-addon-config.json")
+
+    config["ulimits"] = {
+        "nofile": {"soft": 20000, "hard": 40000},
+        "nproc": 32768,  # Mixed format should work
+        "memlock": {"soft": 67108864, "hard": 134217728},
+    }
+
+    valid_config = vd.SCHEMA_ADDON_CONFIG(config)
+    assert valid_config["ulimits"]["nofile"]["soft"] == 20000
+    assert valid_config["ulimits"]["nofile"]["hard"] == 40000
+    assert valid_config["ulimits"]["nproc"] == 32768
+    assert valid_config["ulimits"]["memlock"]["soft"] == 67108864
+    assert valid_config["ulimits"]["memlock"]["hard"] == 134217728
+
+
+def test_ulimits_empty_dict():
+    """Test ulimits with empty dict (default)."""
+    config = load_json_fixture("basic-addon-config.json")
+
+    valid_config = vd.SCHEMA_ADDON_CONFIG(config)
+    assert valid_config["ulimits"] == {}
+
+
+def test_ulimits_invalid_values():
+    """Test ulimits with invalid values."""
+    config = load_json_fixture("basic-addon-config.json")
+
+    # Invalid string values
+    config["ulimits"] = {"nofile": "invalid"}
+    with pytest.raises(vol.Invalid):
+        vd.SCHEMA_ADDON_CONFIG(config)
+
+    # Invalid detailed format
+    config["ulimits"] = {"nofile": {"invalid_key": 1000}}
+    with pytest.raises(vol.Invalid):
+        vd.SCHEMA_ADDON_CONFIG(config)
+
+    # Missing hard value in detailed format
+    config["ulimits"] = {"nofile": {"soft": 1000}}
+    with pytest.raises(vol.Invalid):
+        vd.SCHEMA_ADDON_CONFIG(config)
+
+    # Missing soft value in detailed format
+    config["ulimits"] = {"nofile": {"hard": 1000}}
+    with pytest.raises(vol.Invalid):
+        vd.SCHEMA_ADDON_CONFIG(config)
+
+    # Empty dict in detailed format
+    config["ulimits"] = {"nofile": {}}
+    with pytest.raises(vol.Invalid):
+        vd.SCHEMA_ADDON_CONFIG(config)