Merge pull request #678 from cloudtools/in-progress

Add `in_progress` option to stack config.

docs/config.rst

@@ -404,6 +404,12 @@ A stack has the following keys:
   that will be applied when the CloudFormation stack is created and updated.
   You can use stack policies to prevent CloudFormation from making updates to
   protected resources (e.g. databases). See: https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/protect-stack-resources.html
+**in_progress_behavior**:
+  (optional): If provided, specifies the behavior for when a stack is in
+  `CREATE_IN_PROGRESS` or `UPDATE_IN_PROGRESS`. By default, stacker will raise
+  an exception if the stack is in an `IN_PROGRESS` state. You can set this
+  option to `wait` and stacker will wait for the previous update to complete
+  before attempting to update the stack.
 
 Stacks Example
 ~~~~~~~~~~~~~~

stacker/actions/build.py

@@ -23,6 +23,8 @@
     CompleteStatus,
     FailedStatus,
     SkippedStatus,
+    PENDING,
+    WAITING,
     SUBMITTED,
     INTERRUPTED
 )
@@ -256,7 +258,7 @@ def _launch_stack(self, stack, **kwargs):
 
         """
         old_status = kwargs.get("status")
-        wait_time = STACK_POLL_TIME if old_status == SUBMITTED else 0
+        wait_time = 0 if old_status is PENDING else STACK_POLL_TIME
         if self.cancel.wait(wait_time):
             return INTERRUPTED
 
@@ -340,6 +342,9 @@ def _launch_stack(self, stack, **kwargs):
             return SubmittedStatus("creating new stack")
 
         try:
+            wait = stack.in_progress_behavior == "wait"
+            if wait and provider.is_stack_in_progress(provider_stack):
+                return WAITING
             if provider.prepare_stack_for_update(provider_stack, tags):
                 existing_params = provider_stack.get('Parameters', [])
                 provider.update_stack(

stacker/actions/destroy.py

@@ -10,6 +10,7 @@
 from ..status import (
     CompleteStatus,
     SubmittedStatus,
+    PENDING,
     SUBMITTED,
     INTERRUPTED
 )
@@ -45,7 +46,7 @@ def _generate_plan(self, tail=False):
 
     def _destroy_stack(self, stack, **kwargs):
         old_status = kwargs.get("status")
-        wait_time = STACK_POLL_TIME if old_status == SUBMITTED else 0
+        wait_time = 0 if old_status is PENDING else STACK_POLL_TIME
         if self.cancel.wait(wait_time):
             return INTERRUPTED
 

stacker/config/__init__.py

@@ -332,6 +332,8 @@ class Stack(Model):
 
     stack_policy_path = StringType(serialize_when_none=False)
 
+    in_progress_behavior = StringType(serialize_when_none=False)
+
     def validate_class_path(self, data, value):
         if value and data["template_path"]:
             raise ValidationError(

stacker/stack.py

@@ -74,6 +74,7 @@ def __init__(self, definition, context, variables=None, mappings=None,
         self.protected = protected
         self.context = context
         self.outputs = None
+        self.in_progress_behavior = definition.in_progress_behavior
 
     def __repr__(self):
         return self.fqn

stacker/status.py

@@ -77,6 +77,7 @@ class StackDoesNotExist(SkippedStatus):
 
 
 PENDING = PendingStatus()
+WAITING = PendingStatus(reason="waiting")
 SUBMITTED = SubmittedStatus()
 COMPLETE = CompleteStatus()
 SKIPPED = SkippedStatus()