$ # Ubuntu 16.04
$ #
$ # to generate a client API as specified in the documentation
$ #
$ python src/googleapis/codegen/generate_library.py --api_name=datastore --api_version=v1 --language=cpp --output_dir=datastore
WARNING:root:object without properties ReadOnly: OrderedDict([(u'id', u'ReadOnly'), (u'description', u'Options specific to read-only transactions.'), (u'type', u'object'), (u'properties', OrderedDict())])
WARNING:root:object without properties ReserveIdsResponse: OrderedDict([(u'description', u'The response for Datastore.ReserveIds.'), (u'type', u'object'), (u'properties', OrderedDict()), (u'id', u'ReserveIdsResponse')])
WARNING:root:object without properties RollbackResponse: OrderedDict([(u'id', u'RollbackResponse'), (u'description', u'The response for Datastore.Rollback.\n(an empty message).'), (u'type', u'object'), (u'properties', OrderedDict())])
WARNING:root:object without properties Empty: OrderedDict([(u'id', u'Empty'), (u'description', u'A generic empty message that you can re-use to avoid defining duplicated\nempty messages in your APIs. A typical example is to use it as the request\nor the response type of an API method. For instance:\n\n service Foo {\n rpc Bar(google.protobuf.Empty) returns (google.protobuf.Empty);\n }\n\nThe JSON representation for `Empty` is empty JSON object `{}`.'), (u'type', u'object'), (u'properties', OrderedDict())])
$ #
$ # client files are generated despite warnings above
$ #
$ # Try to build using example CMake rubric, following the pattern in
$ # ...
[ 72%] Building CXX object service_apis/datastore/google/datastore_api/CMakeFiles/google_datastore_api.dir/array_value.cc.o
In file included from /<elided>/google-api-cpp-client/service_apis/datastore/./google/datastore_api/value.h:35:0,
from /<elided>/google-api-cpp-client/service_apis/datastore/./google/datastore_api/array_value.h:32,
from /<elided>/google-api-cpp-client/service_apis/datastore/google/datastore_api/array_value.cc:26:
/<elided>/google-api-cpp-client/service_apis/datastore/./google/datastore_api/entity.h:144:41: error: ‘Value’ was not declared in this scope
const client::JsonCppAssociativeArray<Value > get_properties() const;