How to use resource_config_differs method in localstack

Best Python code snippet using localstack_python

template_deployer.py

Source:template_deployer.py

...1157                "Replacement": "False",1158                "ChangeSetId": change_set_id,1159            },1160        }1161    def resource_config_differs(self, resource_new):1162        """Return whether the given resource properties differ from the existing config (for stack updates)."""1163        resource_id = resource_new["LogicalResourceId"]1164        resource_old = self.resources[resource_id]1165        props_old = resource_old["Properties"]1166        props_new = resource_new["Properties"]1167        ignored_keys = ["LogicalResourceId", "PhysicalResourceId"]1168        old_keys = set(props_old.keys()) - set(ignored_keys)1169        new_keys = set(props_new.keys()) - set(ignored_keys)1170        if old_keys != new_keys:1171            return True1172        for key in old_keys:1173            if props_old[key] != props_new[key]:1174                return True1175        old_status = self.stack.resource_states.get(resource_id) or {}1176        previous_state = (1177            old_status.get("PreviousResourceStatus") or old_status.get("ResourceStatus") or ""1178        )1179        if old_status and "DELETE" in previous_state:1180            return True1181    def merge_properties(self, resource_id, old_stack, new_stack):1182        old_resources = old_stack.template["Resources"]1183        new_resources = new_stack.template["Resources"]1184        new_resource = new_resources[resource_id]1185        old_resource = old_resources[resource_id] = old_resources.get(resource_id) or {}1186        for key, value in new_resource.items():1187            if key == "Properties":1188                continue1189            old_resource[key] = old_resource.get(key, value)1190        old_res_props = old_resource["Properties"] = old_resource.get("Properties", {})1191        for key, value in new_resource["Properties"].items():1192            old_res_props[key] = value1193        # overwrite original template entirely1194        old_stack.template_original["Resources"][resource_id] = new_stack.template_original[1195            "Resources"1196        ][resource_id]1197    def resolve_param(1198        self, logical_id: str, param_type: str, default_value: Optional[str] = None1199    ) -> Optional[str]:1200        if param_type == "AWS::SSM::Parameter::Value<String>":1201            ssm_client = aws_stack.connect_to_service("ssm")1202            param = ssm_client.get_parameter(Name=default_value)1203            return param["Parameter"]["Value"]1204        return None1205    def apply_parameter_changes(self, old_stack, new_stack) -> None:1206        parameters = {1207            p["ParameterKey"]: p1208            for p in old_stack.metadata["Parameters"]  # go through current parameter values1209        }1210        for logical_id, value in new_stack.template["Parameters"].items():1211            default = value.get("Default")1212            provided_param_value = parameters.get(logical_id)1213            param = {1214                "ParameterKey": logical_id,1215                "ParameterValue": provided_param_value if default is None else default,1216            }1217            if default is not None:1218                resolved_value = self.resolve_param(logical_id, value.get("Type"), default)1219                if resolved_value is not None:1220                    param["ResolvedValue"] = resolved_value1221            parameters[logical_id] = param1222        def _update_params(params_list: List[Dict]):1223            for param in params_list:1224                # make sure we preserve parameter values if UsePreviousValue=true1225                if not param.get("UsePreviousValue"):1226                    parameters.update({param["ParameterKey"]: param})1227        _update_params(new_stack.metadata["Parameters"])1228        for change_set in new_stack.change_sets:1229            _update_params(change_set.metadata["Parameters"])1230        # TODO: unclear/undocumented behavior in implicitly updating old_stack parameter here1231        # Note: Indeed it seems that parameters from Change Sets are applied to a stack1232        #   itself, and are preserved even after a change set has been deleted. However,1233        #   a proper implementation would distinguish between (1) Change Sets and (2) Change1234        #   Set Executions - the former are only a template for the changes to be applied,1235        #   whereas the latter actually perform changes (including parameter updates).1236        #   Also, (1) can be deleted, and (2) can only be rolled back (in case of errors).1237        #   Once we have the distinction between (1) and (2) in place, this logic (updating1238        #   the parameters of the stack itself) will become obsolete, then the parameter1239        #   values can be determined by replaying the values of the sequence of (immutable)1240        #   Change Set Executions.1241        old_stack.metadata["Parameters"] = [v for v in parameters.values() if v]1242    # TODO: fix circular import with cloudformation_api.py when importing Stack here1243    def construct_changes(1244        self,1245        existing_stack,1246        new_stack,1247        initialize=False,1248        change_set_id=None,1249        append_to_changeset=False,1250        filter_unchanged_resources=False,1251    ):1252        from localstack.services.cloudformation.provider import StackChangeSet1253        old_resources = existing_stack.template["Resources"]1254        new_resources = new_stack.template["Resources"]1255        deletes = [val for key, val in old_resources.items() if key not in new_resources]1256        adds = [val for key, val in new_resources.items() if initialize or key not in old_resources]1257        modifies = [val for key, val in new_resources.items() if key in old_resources]1258        changes = []1259        for action, items in (("Remove", deletes), ("Add", adds), ("Modify", modifies)):1260            for item in items:1261                item["Properties"] = item.get("Properties", {})1262                if (1263                    not filter_unchanged_resources1264                    or action != "Modify"1265                    or self.resource_config_differs(item)1266                ):1267                    change = self.get_change_config(action, item, change_set_id=change_set_id)1268                    changes.append(change)1269        # append changes to change set1270        if append_to_changeset and isinstance(new_stack, StackChangeSet):1271            new_stack.changes.extend(changes)1272        return changes1273    def apply_changes(1274        self,1275        existing_stack,1276        new_stack,1277        stack_name,1278        change_set_id=None,1279        initialize=False,1280        action=None,1281    ):1282        old_resources = existing_stack.template["Resources"]1283        new_resources = new_stack.template["Resources"]1284        action = action or "CREATE"1285        self.init_resource_status(old_resources, action="UPDATE")1286        # apply parameter changes to existing stack1287        self.apply_parameter_changes(existing_stack, new_stack)1288        # construct changes1289        changes = self.construct_changes(1290            existing_stack,1291            new_stack,1292            initialize=initialize,1293            change_set_id=change_set_id,1294        )1295        # check if we have actual changes in the stack, and prepare properties1296        contains_changes = False1297        for change in changes:1298            res_action = change["ResourceChange"]["Action"]1299            resource = new_resources.get(change["ResourceChange"]["LogicalResourceId"])1300            if res_action != "Modify" or self.resource_config_differs(resource):1301                contains_changes = True1302            if res_action in ["Modify", "Add"]:1303                self.merge_properties(resource["LogicalResourceId"], existing_stack, new_stack)1304        if not contains_changes:1305            raise NoStackUpdates("No updates are to be performed.")1306        # merge stack outputs and conditions1307        existing_stack.outputs.update(new_stack.outputs)1308        existing_stack.conditions.update(new_stack.conditions)1309        # start deployment loop1310        return self.apply_changes_in_loop(1311            changes, existing_stack, stack_name, action=action, new_stack=new_stack1312        )1313    def apply_changes_in_loop(self, changes, stack, stack_name, action=None, new_stack=None):1314        from localstack.services.cloudformation.provider import StackChangeSet...

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