Fix method name collisions for getProperties() (#434)

* Fix method name collisions for getProperties()

* Add a specialized method to fix name collisions for getProperties().

Author: mrinaudo-aws

README.md

@@ -54,6 +54,12 @@ source env/bin/activate
 pip3 install -e /path/to/cloudformation-cli-java-plugin
 ```
 
+Install `pytest-cov`, used when running unit tests for this plugin:
+
+```shell
+pip3 install pytest-cov
+```
+
 You may also want to check out the [CloudFormation CLI](https://github.com/aws-cloudformation/cloudformation-cli) if you wish to make edits to that. In this case, installing them in one operation works well:
 
 ```shell

python/rpdk/java/codegen.py

@@ -17,7 +17,12 @@
 
 from . import __version__
 from .resolver import UNDEFINED, translate_type
-from .utils import safe_reserved, validate_codegen_model, validate_namespace
+from .utils import (
+    safe_reserved,
+    safe_reserved_hook_target,
+    validate_codegen_model,
+    validate_namespace,
+)
 
 LOG = logging.getLogger(__name__)
 
@@ -86,6 +91,7 @@ def __init__(self):
         self.codegen_template_path = None
         self.env.filters["translate_type"] = translate_type
         self.env.filters["safe_reserved"] = safe_reserved
+        self.env.filters["safe_reserved_hook_target"] = safe_reserved_hook_target
         self.namespace = None
         self.package_name = None
 

python/rpdk/java/templates/generate/hook/ResourceHookTarget.java

@@ -47,7 +47,7 @@ public class {{ model_name|uppercase_first_letter }} extends ResourceHookTarget
 
     {% for name, type in properties.items() %}
     @JsonProperty("{{ name }}")
-    private {{ type|translate_type }} {{ name|lowercase_first_letter|safe_reserved }};
+    private {{ type|translate_type }} {{ name|lowercase_first_letter|safe_reserved_hook_target }};
 
     {% endfor %}
     @JsonIgnore

python/rpdk/java/utils.py

@@ -58,12 +58,48 @@
 }
 
 
+# Keywords used in the context of AWS CloudFormation Hooks, when
+# classes are generated, by this plugin, for target resource
+# types. For example, the `properties` item below is marked as a
+# keyword because if a target resource type has a property called
+# `Properties` (see the `AWS::ApiGateway::DocumentationPart` resource
+# type as one of the examples), the generated class code for the
+# target resource type will contain a getter, `getProperties()`, that
+# will collide with `getProperties()` that is already defined for
+# `ResourceHookTarget`. By marking `properties` as a keyword, the
+# generated code for the class will still have a relevant, private
+# variable for the resource type target's property, but whose name
+# will contain an underscore as a suffix: the Lombok-generated getter
+# (and setter) for that private variable will, in turn, contain an
+# underscore suffix as well; see `safe_reserved_hook_target()` below
+# for more information (`safe_reserved_hook_target()` is, in turn,
+# consumed by other parts of a hook's code generation logic in this
+# plugin).
+HOOK_TARGET_KEYWORDS = {
+    "properties",
+}
+
+
 def safe_reserved(token):
     if token in LANGUAGE_KEYWORDS:
         return token + "_"
     return token
 
 
+# This is a specialized method for hooks only. In addition to using
+# LANGUAGE_KEYWORDS (used by safe_reserved()), this function uses
+# HOOK_TARGET_KEYWORDS: the reason for having such a specialized
+# method is that since excluding `properties` will alter an affected
+# target's getters and setters (see this specific case explained in
+# comments for `HOOK_TARGET_KEYWORDS`), we do not want to have the
+# same behavior for resource type extensions, that you also model with
+# this plugin of the CloudFormation CLI.
+def safe_reserved_hook_target(token):
+    if token in LANGUAGE_KEYWORDS or token in HOOK_TARGET_KEYWORDS:
+        return token + "_"
+    return token
+
+
 def validate_namespace(default):
     pattern = r"^[_a-z][_a-z0-9]+$"
 

tests/test_utils.py

@@ -4,6 +4,7 @@
 from rpdk.core.exceptions import WizardValidationError
 from rpdk.java.utils import (
     safe_reserved,
+    safe_reserved_hook_target,
     validate_codegen_model as validate_codegen_model_factory,
     validate_namespace as validate_namespace_factory,
 )
@@ -29,6 +30,14 @@ def test_safe_reserved_unsafe_string():
     assert safe_reserved("class") == "class_"
 
 
+def test_safe_reserved_hook_target_safe_string():
+    assert safe_reserved_hook_target("foo") == "foo"
+
+
+def test_safe_reserved_hook_target_unsafe_string():
+    assert safe_reserved_hook_target("properties") == "properties_"
+
+
 def test_validate_namespace_empty(validate_namespace):
     assert validate_namespace("") == DEFAULT