localstack · MEPalma · Mar 10, 2025 · Feb 25, 2025 · Feb 26, 2025 · Mar 3, 2025
@@ -0,0 +1,121 @@
+from __future__ import annotations
+
+import copy
+import datetime
+import random
+import threading
+from typing import Final, Optional
+
+from localstack.aws.api.stepfunctions import (
+    AliasDescription,
+    Arn,
+    CharacterRestrictedName,
+    DescribeStateMachineAliasOutput,
+    RoutingConfigurationList,
+    StateMachineAliasListItem,
+)
+
+
+class Alias:
+    _mutex: Final[threading.Lock]
+    update_date: Optional[datetime.datetime]
+    name: Final[CharacterRestrictedName]
+    _description: Optional[AliasDescription]
+    _routing_configuration_list: RoutingConfigurationList
+    _state_machine_version_arns: list[Arn]
+    _execution_probability_distribution: list[int]
+    state_machine_alias_arn: Final[Arn]
+    create_date: datetime.datetime
+
+    def __init__(
+        self,
+        state_machine_arn: Arn,
+        name: CharacterRestrictedName,
+        description: Optional[AliasDescription],
+        routing_configuration_list: RoutingConfigurationList,
+    ):
+        self._mutex = threading.Lock()
+        self.update_date = None
+        self.name = name
+        self._description = None
+        self.state_machine_alias_arn = f"{state_machine_arn}:{name}"
+        self.update(description=description, routing_configuration_list=routing_configuration_list)
+        self.create_date = self._get_mutex_date()
+
+    def __hash__(self):
+        return hash(self.state_machine_alias_arn)
+
+    def __eq__(self, other):
+        if isinstance(other, Alias):
+            return self.is_idempotent(other=other)
+        return False
+
+    def is_idempotent(self, other: Alias) -> bool:
+        return all(
+            [
+                self.state_machine_alias_arn == other.state_machine_alias_arn,
+                self.name == other.name,
+                self._description == other._description,
+                self._routing_configuration_list == other._routing_configuration_list,
+            ]
+        )
+
+    @staticmethod
+    def _get_mutex
8000
_date() -> datetime.datetime:
+        return datetime.datetime.now(tz=datetime.timezone.utc)
+
+    def get_routing_configuration_list(self) -> RoutingConfigurationList:
+        return copy.deepcopy(self._routing_configuration_list)
+
+    def is_router_for(self, state_machine_version_arn: Arn) -> bool:
+        with self._mutex:
+            return state_machine_version_arn in self._state_machine_version_arns
+
+    def update(
+        self,
+        description: Optional[AliasDescription],
+        routing_configuration_list: RoutingConfigurationList,
+    ) -> None:
+        with self._mutex:
+            self.update_date = self._get_mutex_date()
+
+            if description is not None:
+                self._description = description
+
+            if routing_configuration_list:
+                self._routing_configuration_list = routing_configuration_list
+                self._state_machine_version_arns = list()
+                self._execution_probability_distribution = list()
+                for routing_configuration in routing_configuration_list:
+                    self._state_machine_version_arns.append(
+                        routing_configuration["stateMachineVersionArn"]
+                    )
+                    self._execution_probability_distribution.append(routing_configuration["weight"])
+
+    def sample(self):
+        with self._mutex:
+            samples = random.choices(
+                self._state_machine_version_arns,
+                weights=self._execution_probability_distribution,
+                k=1,
+            )
+            state_machine_version_arn = samples[0]
+            return state_machine_version_arn
+
+    def to_description(self) -> DescribeStateMachineAliasOutput:
+        with self._mutex:
+            description = DescribeStateMachineAliasOutput(
+                creationDate=self.create_date,
+                name=self.name,
+                description=self._description,
+                routingConfiguration=self._routing_configuration_list,
+                stateMachineAliasArn=self.state_machine_alias_arn,
+            )
+            if self.update_date is not None:
+                description["updateDate"] = self.update_date
+            return description
+
+    def to_item(self) -> StateMachineAliasListItem:
+        return StateMachineAliasListItem(
+            stateMachineAliasArn=self.state_machine_alias_arn, creationDate=self.create_date
+        )
@@ -103,6 +103,10 @@ class Execution:
     region_name: str
 
     state_machine: Final[StateMachineInstance]
+    state_machine_arn: Final[Arn]
+    state_machine_version_arn: Final[Optional[Arn]]
+    state_machine_alias_arn: Final[Optional[Arn]]
+
     start_date: Final[Timestamp]
     input_data: Final[Optional[json]]
     input_details: Final[Optional[CloudWatchEventsExecutionDataDetails]]
@@ -136,6 +140,7 @@ def __init__(
         activity_store: dict[Arn, Activity],
         input_data: Optional[json] = None,
         trace_header: Optional[TraceHeader] = None,
+        state_machine_alias_arn: Optional[Arn] = None,
     ):
         self.name = name
         self.sm_type = sm_type
@@ -144,6 +149,13 @@ def __init__(
         self.account_id = account_id
         self.region_name = region_name
         self.state_machine = state_machine
+        if isinstance(state_machine, StateMachineVersion):
+            self.state_machine_arn = state_machine.source_arn
+            self.state_machine_version_arn = state_machine.arn
+        else:
+            self.state_machine_arn = state_machine.arn
+            self.state_machine_version_arn = None
+        self.state_machine_alias_arn = state_machine_alias_arn
         self.start_date = start_date
         self._cloud_watch_logging_session = cloud_watch_logging_session
         self.input_data = input_data
@@ -167,7 +179,7 @@ def to_start_output(self) -> StartExecutionOutput:
     def to_describe_output(self) -> DescribeExecutionOutput:
         describe_output = DescribeExecutionOutput(
             executionArn=self.exec_arn,
-            stateMachineArn=self.state_machine.arn,
+            stateMachineArn=self.state_machine_arn,
             name=self.name,
             status=self.exec_status,
             startDate=self.start_date,
@@ -183,6 +195,10 @@ def to_describe_output(self) -> DescribeExecutionOutput:
             describe_output["error"] = self.error
         if self.cause is not None:
             describe_output["cause"] = self.cause
+        if self.state_machine_version_arn is not None:
+            describe_output["stateMachineVersionArn"] = self.state_machine_version_arn
+        if self.state_machine_alias_arn is not None:
+            describe_output["stateMachineAliasArn"] = self.state_machine_alias_arn
         return describe_output
 
     def to_describe_state_machine_for_execution_output(
@@ -231,6 +247,8 @@ def to_execution_list_item(self) -> ExecutionListItem:
         )
         if state_machine_version_arn is not None:
             item["stateMachineVersionArn"] = state_machine_version_arn
+        if self.state_machine_alias_arn is not None:
+            item["stateMachineAliasArn"] = self.state_machine_alias_arn
         return item
 
     def to_history_output(self) -> GetExecutionHistoryOutput:

@@ -30,6 +30,7 @@
 from localstack.services.stepfunctions.asl.static_analyser.variable_references_static_analyser import (
     VariableReferencesStaticAnalyser,
 )
+from localstack.services.stepfunctions.backend.alias import Alias
 from localstack.utils.strings import long_uid
 
 
@@ -163,6 +164,7 @@ class StateMachineRevision(StateMachineInstance):
     _next_version_number: int
     versions: Final[dict[RevisionId, Arn]]
     tag_manager: Final[TagManager]
+    aliases: Final[set[Alias]]
 
     def __init__(
         self,
@@ -194,6 +196,7 @@ def __init__(
         self.tag_manager = TagManager()
         if tags:
             self.tag_manager.add_all(tags)
+        self.aliases = set()
 
     def create_revision(
         self,

@@ -3,6 +3,7 @@
 
 from localstack.aws.api.stepfunctions import Arn
 from localstack.services.stepfunctions.backend.activity import Activity
+from localstack.services.stepfunctions.backend.alias import Alias
 from localstack.services.stepfunctions.backend.execution import Execution
 from localstack.services.stepfunctions.backend.state_machine import StateMachineInstance
 from localstack.services.stores import AccountRegionBundle, BaseStore, LocalAttribute
@@ -11,6 +12,8 @@
 class SFNStore(BaseStore):
     # Maps ARNs to state machines.
     state_machines: Final[dict[Arn, StateMachineInstance]] = LocalAttribute(default=dict)
+    # Map Alias ARNs to state machine aliases
+    aliases: Final[dict[Arn, Alias]] = LocalAttribute(default=dict)
     # Maps Execution-ARNs to state machines.
     executions: Final[dict[Arn, Execution]] = LocalAttribute(
         default=OrderedDict