As mentioned previously in this chapter, App Engine provides several service integrations spanning the Google Cloud product and service catalog. A large set of these integrations is provided through client libraries that are only available to services running in the standard environment, but developers can achieve similar results in the flexible environment by leveraging Google's provided common libraries, shown as follows:
Many resources are shared between services in the standard environment
As depicted in the preceding diagram, many resources provided by the App Engine service integrations are shared across services rather than being provided on a per-service or per-instance basis. For example, data stored in Memcache or Datastore will be available to all services within a Google Cloud project. This sharing of resources should be considered when designing App Engine services as it can be a double-edged sword. On one hand, shared resources can simplify...