sceptre.resolvers package¶
- class sceptre.resolvers.CustomYamlTagBase(argument=None, stack=None)[source]¶
Bases:
object
A base class for custom Yaml Elements (i.e. hooks and resolvers).
This base class takes care of common functionality needed by subclasses: | * logging setup (associated with stacks) | * Creating unique clones associated with individual stacks (applied recursively down to all | resolvers in the argument) | * On-stack-connect setup that might be needed once connected to a Stack (applied recursively down to | all resolvers in the argument) | * Automatically resolving resolvers in the argument when accessing self.argument
- property argument: Any¶
This is the resolver or hook’s argument.
This property will resolve all nested resolvers inside the argument, but only if this instance has been associated with a Stack.
Resolving nested resolvers will result in their values being replaced in the dict/list they were in with their resolved value, so we won’t have to resolve them again.
Any resolvers that “resolve to nothing” (i.e. return None) will be removed from the dict/list they were in.
If this property is accessed BEFORE the instance has a stack, it will return the raw argument value. This is to safeguard any __init__() behaviors from triggering resolution prematurely.
- Return type
- clone_for_stack(stack)[source]¶
Obtains a clone of the current object, setup and ready for use for a given Stack instance.
- Return type
TypeVar
(Self
)
- logger = <Logger sceptre.resolvers (WARNING)>¶
- class sceptre.resolvers.ResolvableContainerProperty(name, placeholder_type=PlaceholderType.explicit)[source]¶
Bases:
ResolvableProperty
This is a descriptor class used to store an attribute that may CONTAIN Resolver objects. Resolvers will be resolved upon access of this property. When resolvers are resolved, they will be replaced in the container with their resolved value, in order to avoid redundant resolutions.
Supports nested dictionary and lists.
- Parameters
name (str) – Attribute suffix used to store the property in the instance.
- class ResolveLater(instance, name, key, resolution_function)[source]¶
Bases:
object
Represents a value that could not yet be resolved but can be resolved in the future.
- assign_value_to_stack(stack, value)[source]¶
Assigns a COPY of the specified value to the stack instance. This method copies the value rather than directly assigns it to avoid bugs related to shared objects in memory.
- get_resolved_value(stack, stack_class)[source]¶
Obtains the resolved value for this property. Any resolvers that resolve to None will have their key/index removed from their dict/list where they are. Other resolvers will have their key/index’s value replace with the resolved value to avoid redundant resolutions.
- class sceptre.resolvers.ResolvableProperty(name, placeholder_type=PlaceholderType.explicit)[source]¶
Bases:
ABC
This is an abstract base class for a descriptor used to store an attribute that have values associated with Resolver objects.
- Parameters
name (
str
) – Attribute suffix used to store the property in the instance.placeholder_type – The type of placeholder that should be returned, when placeholders are allowed, when a resolver can’t be resolved.
- abstract assign_value_to_stack(stack, value)[source]¶
Implement this method to assign the value to the resolvable property.
- abstract get_resolved_value(stack, stack_class)[source]¶
Implement this method to return the value of the resolvable_property.
- Return type
- class sceptre.resolvers.ResolvableValueProperty(name, placeholder_type=PlaceholderType.explicit)[source]¶
Bases:
ResolvableProperty
This is a descriptor class used to store an attribute that may BE a single Resolver object. If it is a resolver, it will be resolved upon access of this property. When resolved, the resolved value will replace the resolver on the stack in order to avoid redundant resolutions.
- Parameters
name (str) – Attribute suffix used to store the property in the instance.
- assign_value_to_stack(stack, value)[source]¶
Assigns the value to the Stack instance passed, setting up and cloning the value if it is a Resolver.
- class sceptre.resolvers.Resolver(argument=None, stack=None)[source]¶
Bases:
CustomYamlTagBase
Resolver is an abstract base class that should be subclassed by all Resolvers.
Submodules¶
sceptre.resolvers.environment_variable module¶
sceptre.resolvers.file_contents module¶
sceptre.resolvers.stack_output module¶
- class sceptre.resolvers.stack_output.StackOutput(*args, **kwargs)[source]¶
Bases:
StackOutputBase
Resolver for retrieving the value of a Stack output within the current Sceptre StackGroup. Adds the target Stack to the dependencies of the Stack using the Resolver.
- Parameters
argument (str in the format
"<stack name>::<output key>"
) – The Stack name and output name to get.
- class sceptre.resolvers.stack_output.StackOutputBase(*args, **kwargs)[source]¶
Bases:
Resolver
A abstract base class which provides methods for getting Stack outputs.
- class sceptre.resolvers.stack_output.StackOutputExternal(*args, **kwargs)[source]¶
Bases:
StackOutputBase
Resolver for retrieving the value of an output of any Stack within the current Sceptre stack_group’s account and region.
- Parameters
argument (str in the format
"<full stack name>::<output key>"
) – The Stack name and output name to get.