[feat] Improve enums. (#127)

This uses proto-plus enums, which add enum support to the
marshal and cause enums (rather than ints) to be returned,
and add support for accepting strings.

Author: Luke Sneeringer

packages/gapic-generator/gapic/templates/$namespace/$name_$version/$sub/types/$proto.py.j2

@@ -1,12 +1,8 @@
 {% extends "_base.py.j2" %}
 
 {% block content -%}
-{% with e = proto.disambiguate('enum'), p = proto.disambiguate('proto') %}
-{% if proto.all_enums|length -%}
-import enum{% if e != 'enum' %} as {{ e }}{% endif %}
-
-{% endif -%}
-{% if proto.messages|length -%}
+{% with p = proto.disambiguate('proto') %}
+{% if proto.messages|length or proto.all_enums|length -%}
 import proto{% if p != 'proto' %} as {{ p }}{% endif -%}
 {% endif %}
 

packages/gapic-generator/gapic/templates/$namespace/$name_$version/$sub/types/_enum.py.j2

@@ -1,4 +1,4 @@
-class {{ enum.name }}({{ e }}.IntEnum):
+class {{ enum.name }}({{ p }}.Enum):
     r"""{{ enum.meta.doc|rst(indent=4) }}"""
     {% for enum_value in enum.values -%}
     {{ enum_value.name }} = {{ enum_value.number }}

packages/gapic-generator/gapic/templates/setup.py.j2

@@ -22,7 +22,7 @@ setuptools.setup(
         'google-api-core >= 1.8.0, < 2.0.0dev',
         'googleapis-common-protos >= 1.5.8',
         'grpcio >= 1.10.0',
-        'proto-plus >= 0.3.0',
+        'proto-plus >= 0.4.0',
     ),
     classifiers=[
         'Development Status :: 3 - Alpha',