Cloud app design pattern

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http://estado.ng.bluemix.net/,it will report all the service status.

When we design the app on the cloud ,we must think about the best pattern and best practices for developing modern applications for cloud platforms.

The twelve-factor app is a methodology for building software-as-a-service apps that:

• Use declarative formats for setup automation, to minimize time and cost for new developers joining the project;
• Have a clean contract with the underlying operating system, offering maximum portability between execution environments;
• Are suitable for deployment on modern cloud platforms, obviating the need for servers and systems administration;
• Minimize divergence between development and production, enabling continuous deployment for maximum agility;
• And can scale up without significant changes to tooling, architecture, or development practices.

The twelve-factor methodology can be applied to apps written in any programming language, and which use any combination of backing services (database, queue, memory cache, etc).The detail content you can visit http://12factor.net/

I. Codebase
One codebase tracked in revision control, many deploys
II. Dependencies
Explicitly declare and isolate dependencies
III. Config
Store config in the environment
IV. Backing Services
Treat backing services as attached resources
V. Build, release, run
Strictly separate build and run stages
VI. Processes
Execute the app as one or more stateless processes
VII. Port binding
Export services via port binding
VIII. Concurrency
Scale out via the process model
IX. Disposability
Maximize robustness with fast startup and graceful shutdown
X. Dev/prod parity
Keep development, staging, and production as similar as possible
XI. Logs
Treat logs as event streams
XII. Admin processes
Run admin/management tasks as one-off processes