def test_export_basic_output(self):
"""Should be able to create and export a simple CloudFormation Output object."""
output = Output(Description="Stuff we need",
Value=6644,
Export={"Name": "ImportantThingy"})
exported = output.export("yaml")
assert exported == dedent("""
---
Description: Stuff we need
Export:
Name: ImportantThingy
Value: 6644
""")
def test_cannot_merge_if_two_outputs_have_the_same_export_name(self):
# Setup
export_name = "SpecialExportedValue"
source_output = Output(Value=123, Export={"Name": export_name})
source = Stack(Outputs={"SourceOutput": source_output})
target_output = Output(Value=987, Export={"Name": export_name})
target = Stack(Outputs={"TargetOutput": target_output})
# Exercise & Verify
with pytest.raises(StackMergeError) as excinfo:
target.merge_stack(source)
assert "the target stack already has exports" in str(
excinfo.value).lower()
def test_dont_create_export_name_for_output_when_it_is_not_set(self):
# Setup
name = "SomeItemName"
stack = Stack(Outputs={name: (Output(Value="HelloWorld"))})
# Exercise
new_stack = stack.with_prefixed_names(self.STACK_PREFIX)
# Verify
new_output = new_stack.Outputs[self.STACK_PREFIX + name]
assert getattr(new_output, "Export", None) is None
def test_prefix_export_name_for_output(self):
# Setup
name = "SomeItemName"
export_name = "SomeGloballyScopedValue"
output = Output(Value="HelloWorld", Export={"Name": export_name})
stack = Stack(Outputs={name: output})
# Exercise
new_stack = stack.with_prefixed_names(self.STACK_PREFIX)
# Verify
assert new_stack.Outputs[
self.STACK_PREFIX +
name]["Export"]["Name"] == self.STACK_PREFIX + export_name
def generate_stack_template():
stack = Stack()
stack.Resources["WebServer"] = create_ec2_instance("webserver")
stack.Resources["DatabaseServer"] = dbserver = create_ec2_instance(
"dbserver", "t2.medium")
dbserver.DeletionPolicy = "Retain"
stack.Outputs["DatabaseServerIp"] = Output(
Description=f"Internal IP address for the database server",
Value=GetAtt(dbserver, "PrivateIp"),
)
stack.tag(application="api-service",
environment="test",
owner=os.environ.get("USER"))
return stack.export("yaml")
class TestPrefixedNames:
"""Verify the object name prefixing functionality."""
ATTRIBUTE_PARAMETRIZE_NAMES = 'stack_attribute,item'
PREFIXABLE_ATTRIBUTE_EXAMPLES = [
("Parameters", Parameter(Type="String")),
("Resources", SimpleResource()),
# TODO #87 Add Condition when we have a helper class
# TODO #87 Add Mapping when we have a helper class
# TODO #87 Add Metadata when we have a helper class. Consider whether we should retain the Metadata or just throw it away
]
OUTPUT_EXAMPLES = [
("Outputs", Output(Value="HelloWorld")),
("Outputs",
Output(Value="HelloWorld", Export={"Name":
"SomeGloballyScopedValue"})),
]
STACK_PREFIX = "NewScope"
# Basic Prefixing Behaviour
# -------------------------
def test_return_value_is_a_new_stack(self):
# Setup
stack = Stack(Resources={"SomeName": SimpleResource()})
# Exercise
new_stack = stack.with_prefixed_names(self.STACK_PREFIX)
# Verify
assert isinstance(new_stack, Stack)
assert new_stack is not stack
@given(aws_logical_name_strategy())
def test_prefix_is_an_underscored_alphanumeric_string(self, prefix):
# Setup
stack = Stack(Resources={"SomeName": SimpleResource()})
# Exercise & Verify
_ = stack.with_prefixed_names(prefix) # Should not throw an error
def test_prefix_cannot_be_empty(self):
# Setup
stack = Stack(Resources={"SomeName": SimpleResource()})
# Exercise & Verify
with pytest.raises(ValueError) as excinfo:
_ = stack.with_prefixed_names("")
assert "empty" in str(excinfo.value).lower()
def test_prefix_must_have_leading_capital(self):
# Setup
stack = Stack(Resources={"SomeName": SimpleResource()})
# Exercise & Verify
with pytest.raises(ValueError) as excinfo:
_ = stack.with_prefixed_names(
"lowercasedCamelsAreBactrianButInvalid")
assert "uppercase" in str(excinfo.value).lower()
@given(st.from_regex(re.compile(r"^[A-Z]\w*\W+\w*$", re.ASCII)))
def test_prefix_cannot_contain_special_characters(self, prefix):
# Setup
stack = Stack(Resources={"SomeName": SimpleResource()})
# Exercise & Verify
with pytest.raises(ValueError) as excinfo:
_ = stack.with_prefixed_names(prefix)
assert "alphanumeric" in str(excinfo.value).lower()
@pytest.mark.parametrize('prefix', [
None,
123,
Stack(),
])
def test_prefix_must_be_string(self, prefix):
# Setup
stack = Stack(Resources={"SomeName": SimpleResource()})
# Exercise & Verify
with pytest.raises(TypeError) as excinfo:
_ = stack.with_prefixed_names(prefix)
assert "string" in str(excinfo.value).lower()
# Prefixable Dictionaries
# -----------------------
@pytest.mark.parametrize(ATTRIBUTE_PARAMETRIZE_NAMES,
PREFIXABLE_ATTRIBUTE_EXAMPLES)
def test_item_is_prefixed_in_the_new_stack(self, stack_attribute, item):
# Setup
item_name = "SomeItemName"
stack = Stack()
stack[stack_attribute] = {item_name: item}
# Exercise
new_stack = stack.with_prefixed_names(self.STACK_PREFIX)
# Verify
new_name = self.STACK_PREFIX + item_name
assert len(new_stack[stack_attribute]) == 1
assert item_name not in new_stack[stack_attribute]
assert new_stack[stack_attribute][new_name] is item
@pytest.mark.parametrize(ATTRIBUTE_PARAMETRIZE_NAMES, OUTPUT_EXAMPLES)
def test_output_is_prefixed_in_the_new_stack_but_not_same_object(
self, stack_attribute, item):
# Setup
item_name = "SomeItemName"
stack = Stack()
stack[stack_attribute] = {item_name: item}
# Exercise
new_stack = stack.with_prefixed_names(self.STACK_PREFIX)
# Verify
new_name = self.STACK_PREFIX + item_name
assert len(new_stack[stack_attribute]) == 1
assert item_name not in new_stack[stack_attribute]
new_item = new_stack[stack_attribute][new_name]
assert new_item is not item
assert getattr(new_item, "Description",
None) == getattr(item, "Description", None)
assert getattr(new_item, "Value", None) is getattr(item, "Value", None), \
"This should be the same because it might be a Reference function or some such"
@pytest.mark.parametrize(ATTRIBUTE_PARAMETRIZE_NAMES,
PREFIXABLE_ATTRIBUTE_EXAMPLES + OUTPUT_EXAMPLES)
def test_item_is_not_removed_from_original_stack(self, stack_attribute,
item):
# Setup
item_name = "SomeItemName"
stack = Stack()
stack[stack_attribute] = {item_name: item}
# Exercise
_ = stack.with_prefixed_names(self.STACK_PREFIX)
# Verify
assert len(stack[stack_attribute]) == 1
assert stack[stack_attribute][item_name] is item
assert stack[stack_attribute][item_name] == item
# Special Cases
# -------------
def test_copy_cfn_template_version(self):
"""AWSTemplateFormatVersion should be a string which we copy across unchanged"""
# Setup
version_string = "WhatIfThisWaSemanticallyVersioned.1.0"
stack = Stack(AWSTemplateFormatVersion=version_string)
# Exercise
new_stack = stack.with_prefixed_names(self.STACK_PREFIX)
# Verify
assert new_stack.AWSTemplateFormatVersion == version_string
assert stack.AWSTemplateFormatVersion == version_string, "Old stack should not be modified"
def test_copy_sam_version_in_transform(self):
"""If set, Transform should be the version of the Serverless Application Model
being used, which we copy across unchanged.
"""
# Setup
version_string = "AWS::Serverless-1999-12-31"
stack = Stack(Transform=version_string)
# Exercise
new_stack = stack.with_prefixed_names(self.STACK_PREFIX)
# Verify
assert new_stack.Transform == version_string
assert stack.Transform == version_string, "Old stack should not be modified"
def test_modify_content_of_description(self):
# Setup
stack = Stack(Description=LOREM_IPSUM)
# Exercise
new_stack = stack.with_prefixed_names(self.STACK_PREFIX)
# Verify
assert self.STACK_PREFIX in new_stack.Description
assert LOREM_IPSUM in new_stack.Description
assert stack.Description == LOREM_IPSUM, "Old stack should not be modified"
def test_create_description_when_it_is_not_set(self):
# Setup
stack = Stack()
# Exercise
new_stack = stack.with_prefixed_names(self.STACK_PREFIX)
# Verify
assert self.STACK_PREFIX == new_stack.Description
assert not hasattr(
stack, "Description"
) or stack.Description is None, "Old stack should not be modified"
def test_prefix_export_name_for_output(self):
# Setup
name = "SomeItemName"
export_name = "SomeGloballyScopedValue"
output = Output(Value="HelloWorld", Export={"Name": export_name})
stack = Stack(Outputs={name: output})
# Exercise
new_stack = stack.with_prefixed_names(self.STACK_PREFIX)
# Verify
assert new_stack.Outputs[
self.STACK_PREFIX +
name]["Export"]["Name"] == self.STACK_PREFIX + export_name
def test_dont_create_export_name_for_output_when_it_is_not_set(self):
# Setup
name = "SomeItemName"
stack = Stack(Outputs={name: (Output(Value="HelloWorld"))})
# Exercise
new_stack = stack.with_prefixed_names(self.STACK_PREFIX)
# Verify
new_output = new_stack.Outputs[self.STACK_PREFIX + name]
assert getattr(new_output, "Export", None) is None
class TestMergeStack:
"""Verify the stack merge functionality."""
PARAMETRIZE_NAMES = 'stack_attribute,item'
MERGED_ATTRIBUTE_EXAMPLES = [
("Outputs", Output(Value="HelloWorld")),
("Parameters", Parameter(Type="String")),
("Resources", SimpleResource()),
# TODO #87 Add Condition when we have a helper class
# TODO #87 Add Mapping when we have a helper class
]
# TODO #87 test_does_not_copy_metadata when we have a Metadata class
def test_merge_returns_target_stack(self):
# Setup
source = Stack(Resources={"SomeResource": SimpleResource()})
target = Stack()
# Exercise
result = target.merge_stack(source)
# Verify
assert target is result
@pytest.mark.parametrize(PARAMETRIZE_NAMES, MERGED_ATTRIBUTE_EXAMPLES)
def test_item_is_added_to_the_target_stack(self, stack_attribute, item):
# Setup
item_name = "SomeChildProperty"
source = Stack()
source[stack_attribute] = {item_name: item}
target = Stack()
# Exercise
target.merge_stack(source)
# Verify
assert len(target[stack_attribute]) == 1
assert target[stack_attribute][item_name] is item
@pytest.mark.parametrize(PARAMETRIZE_NAMES, MERGED_ATTRIBUTE_EXAMPLES)
def test_item_is_not_removed_from_source_stack(self, stack_attribute,
item):
# Setup
item_name = "SomeChildProperty"
source = Stack()
source[stack_attribute] = {item_name: item}
target = Stack()
# Exercise
target.merge_stack(source)
# Verify
assert len(source[stack_attribute]) == 1
assert source[stack_attribute][item_name] is item
@pytest.mark.parametrize(PARAMETRIZE_NAMES, MERGED_ATTRIBUTE_EXAMPLES)
def test_does_not_clobber_existing_items_in_target_stack(
self, stack_attribute, item):
# Setup
item_name = "SomeChildProperty"
source = Stack()
source[stack_attribute] = {item_name: item}
existing_item = copy(item)
existing_item_name = "SomeOldItem"
target = Stack()
target[stack_attribute] = {existing_item_name: existing_item}
# Exercise
target.merge_stack(source)
# Verify
assert len(target[stack_attribute]) == 2
assert target[stack_attribute][item_name] is item
assert target[stack_attribute][existing_item_name] is existing_item
def test_does_not_copy_description(self):
# Setup
source = Stack(Description="Source Description")
original_description = "Target Description"
target = Stack(Description=original_description)
# Exercise
target.merge_stack(source)
# Verify
assert target.Description == original_description
def test_cannot_merge_if_template_version_is_different(self):
source = Stack(AWSTemplateFormatVersion="123")
target = Stack(AWSTemplateFormatVersion="456")
# Exercise & Verify
with pytest.raises(StackMergeError) as excinfo:
target.merge_stack(source)
assert "template version" in str(excinfo.value).lower()
def test_cannot_merge_if_sam_transform_version_is_different(self):
source = Stack(Transform="123")
target = Stack(Transform="456")
# Exercise & Verify
with pytest.raises(StackMergeError) as excinfo:
target.merge_stack(source)
assert "transform version" in str(excinfo.value).lower()
@pytest.mark.parametrize(PARAMETRIZE_NAMES, MERGED_ATTRIBUTE_EXAMPLES)
def test_cannot_merge_if_logical_name_is_already_used_for_that_item_type(
self, stack_attribute, item):
# Setup
item_name = "SomeChildProperty"
source = Stack()
source[stack_attribute] = {item_name: item}
existing_item = copy(item)
target = Stack()
target[stack_attribute] = {item_name: existing_item}
# Exercise & Verify
with pytest.raises(StackMergeError) as excinfo:
target.merge_stack(source)
assert "in this stack already has an item with the logical name" in str(
excinfo.value)
def test_cannot_merge_if_two_outputs_have_the_same_export_name(self):
# Setup
export_name = "SpecialExportedValue"
source_output = Output(Value=123, Export={"Name": export_name})
source = Stack(Outputs={"SourceOutput": source_output})
target_output = Output(Value=987, Export={"Name": export_name})
target = Stack(Outputs={"TargetOutput": target_output})
# Exercise & Verify
with pytest.raises(StackMergeError) as excinfo:
target.merge_stack(source)
assert "the target stack already has exports" in str(
excinfo.value).lower()