In-App Engine User will provide the application code, one App per project it is Regional, Serverless, PaaS also provide CaaS service, which is fully managed service, it provides auto load balancing, auto-scaling, versioning of the App, and traffic splitting. The programmer will focus on the code, not on the infra.
Two Types of App Engine.
App Engine Standard
App Engine Flexible
App Engine Standard:
App Engine Standard-application run on preconfigured Standbox, restrictions in langauges-Go,Java,PHP,Node.js,Python,Ruby,It can scale to zero instances when there is no traffic. Maximum request timeout ranges from 1 to 10 minutes. SSH access for debugging is not available. Applications can write to the /temp directory.
Use Case:
App Engine Standard is an excellent choice for applications written in supported languages that require rapid scalability based on traffic fluctuations. It is particularly suitable for stateless HTTP web applications that often experience sudden surges in traffic.
App Engine Flexible:
App Engine Flexible-Application instances run within Docker containers,App Engine Flexible offers runtime environments that grant access to background processes and local disks. It requires a minimum of one instance and allows a maximum request timeout of 60 minutes. With SSH support for debugging, you can leverage its flexibility to deploy custom Docker containers. In addition, you have the ability to specify CPU and memory configurations. App Engine Flexible also provides health checks and autohealing capabilities. Notably, containers in App Engine Flexible are restarted once per week to maintain optimal performance.
Use Case:
App Engine Flexible is designed to scale, although the startup time of its instances typically takes minutes rather than seconds. It becomes an optimal choice when your application relies on microservices, custom code, or when specific libraries are not accessible in App Engine Standard. It is particularly suitable for applications that consistently experience traffic and for general-purpose apps.