Microservices Architecture Style

As traditional enterprises work to embrace business deployment agility of new age internet companies and innovations in engineering practices, the modern application development has grown increasingly complex. The large, monolithic codebases that traditionally power enterprise applications make it difficult to quickly launch new business capabilities. The application users are empowered and more demanding than ever – the modern enterprises need to scale effectively and enable continuous deployments to ensure customers are provided with high performance with the seamless user experience.

Due to these trends, there is a demand for a new software architecture pattern/style that can address the requirements of the modern age enterprise apps. The Microservices architecture style is the answer to business agility in the form of scalability, modularity and rapid deployments.

What Is Microservices?

It is an architectural style to develop a small/coarse grained services separated by business boundaries. Thus each service is autonomous in nature and can scale independently. Each service can communicate each other via REST APIs and can be deployed remotely or locally.

Monolithic pain points

Before Microservices, a common approach to design an application was to use a monolithic architecture. In this mode of development, the application is deployed as a single deployment artifact. Following are pain points associated with classic monolithic codebases.

1. Large monolithic code base will have the challenge to release new services and also difficulty in maintaining large code base
2. Modules can’t scale independently
3. Enable / Disable services without affecting existing features will be always a challenge
4. Any small change in the code will introduce many regression testing/complex deployment scenarios.
5. Will have challenges in continuous deployments

Difference with SOA

At outset, both architecture styles look similar. But there are subtle differences, the noteworthy are:

1. SOA uses ESBs while Microservices can leverage lightweight message gateways
2. Microservices are stateless implemented via REST APIs while SOA can be stateful
3. SOA focuses on reusability wherein Microservices is for decoupling

Tool support

Lightweight containers like Docker will provide provides a runtime environment for deployment and provides isolation with other services. There is many open sources / COTS tooling support available for Microservices enablement.

Pros / Cons

Following table summarizes briefly about Microservices advantages/disadvantages. The Microservices architecture can’t be suited for each app. The recommended approach is to gradually convert highly customer facing modules to Microservices, stabilize the rapid deployment cycle and gain the experience by maintaining these services over the period of time. This will have less impact on development teams/organization change management activities as teams have to adopt new way of developing the apps.

Advantages

1. Decoupled services can have isolated life cycle
2. Faster time to market; less regressions
3. Modular in nature, hence flexible development and deployment plans
4. Can scale independently

Disadvantages

1. Monitoring the many services
2. Developer skill set – For example: Microservices are distributed in nature. Hence there will be added complexity such as network latency, network unreliability, also understanding the DevOps culture
3. Technology learning curve – new set of tools to learn

Minimilist Architecture Development

Introduction

The new age enterprise application development is very challenging and poses significant design/analysis thinking before one could develop the new system. In the process, the architecture/design team would carry many architecture/design workshops and create architecture descriptions. But the problem with these teams is that descriptions are very elaborative in nature with lot more granular details covering existing “As-Is” information rather than “To-Be” system. Thus, creating lot more divide and less buy-in from project teams.
This blog would discuss how to adopt minimalist architecture description so that it will have all necessary information from the Sprint-1 onwards to kick-start the development. As a rule of thumb, the architecture description should be less than 20 pages. If we try to combine many architecture views/stakeholder’s details, it will be cluttered and understanding architecture decisions would become difficult.

The “minimalist” description

At the bare minimum, architecture description shall contain:
1. Architecturally Significant Requirements (ASR) – From the requirement perspective, scout all architecturally significant requirements and prepare catalogue out of it.
2. Architecturally Significant Decisions (ASD) – Would contain decision taken for each of the ASRs with the rationale behind for each such decision.
3. Architecture Views – Shall contain the solution, technology, data and deployment views. In addition, each view can briefly highlight the technical spikes identified / outcome of such exercises to validate decisions.

Architecture development steps

In order to achieve the minimalist useful architecture descriptions, an architect can follow ordered development steps. Following mind map would describe these steps (Personally I prepared this mindmap and use this as quick reference guide!!)
Depending on the individual application requirements, one can omit the steps – if it not found to be so useful. But in general, following steps would ensure that all critical steps under architecture design are covered.

Conclusion

As saying goes “less luggage more comfort”, carrying heavy architecture descriptions would be the pain for all the members involved in the engagement. So it is imperative that architecture teams would adopt “minimalist” approach as described above so that these artifacts would look neat and tidy with significant key takeaways.

Cloud Transformation Journey

CONTEXT

Every enterprise would like to mark its presence in cloud to be part of digital transformation journey. The cloud platform would offer enterprise services in best economical scale that is otherwise priced heavily when it done on-premises. The cloud transformation offers many distinct benefits, in particular

·       Cost of ownership

·       Design innovative solutions by leveraging latest cloud services

·       Business Continuity / Availability

·       On-demand scale

Concisely, need was to move applications out from on-premises data center and derive cost for running each application under enterprise portfolio.

CHALLENGES

The cloud transformation journey is not trivial and can pose adverse effects when it not assessed and planned properly. As part of the program, it is key to assess the “AS-IS” environment and identify the key challenges in “TO-BE” state. Following are few challenges present as we embarked the transformation.

o   Legacy applications developed in different timeframes (more than decade old apps)

o   Heterogeneous identify management solutions present at on-premises

o   Remediate applications to different runtime containers

o   Migrate database servers to different cloud database services

o   Refactor legacy applications to make it cloud compatible – In particular Platform as a Service (PaaS)

o   Harmonize the application build / release cycles

o   Centralize the application code base that supports modern DevOps practices / tools

SOLUTIONS

The Microsoft Azure chosen as part of the target state. All applications are destined to be part of PaaS service. The entire solution devised around people, process and technology to meet in best possible timeframe with minimal cost.

o   Re-organized the teams with unique skills on product/business owners, cloud infra engineering and application architecture / development

o   Application architecture/development teams divided into distinct technology streams with specific reusable solutions for each of those stacks

o   SCRUM adopted as engineering process with 02-week sprint duration. Teams are distributed and used Azure DevOps tool for end-to-end traceability and tracking.

o   The business/product owner team(s) is ahead of engineering teams with gap analysis on candidate apps. That is primary artefact available for DEV teams to kick start transformation activities.

o   Entire program is divided into distinct phases like pilot followed by bulk transformations. The pilot phase helped to unlock any technical spikes and baseline the target architecture. The theme for pilot phase was “fail fast and cheap”

o   All experiences and solutions recorded and made it as reusable solutions for repeated problems.

o   Many of the Azure services used for the betterment of the existing application. Created the automated environment for the application deployment and its monitoring. Few noteworthy Azure services used are - AppServices, Azure Deployment Slots, Logic Apps, Web Jobs/Schedulers, Key Vault, Redis Cache, Azure AD, Hybrid Connection Managers, Azure Portal Services, Application Insights, Azure DevOps CI/CD pipelines, Azure Automation Jobs, ARM templates, KUDU, Azure Storage accounts, Maven Feed, Azure SQL Managed Instances, API Management etc.

RESULTS

Many applications transformed to Azure PaaS with better application maintenance and monitoring with frequent release cycles. The dedicated environments for application development cycle created otherwise it was not available. On demand basis, the application wise costing /billing details are available with latest Azure capabilities. This has helped to make informed decisions on application future state.

Issue free books till 10th Standard

Can't govt take an action to issue free books for all students in India up-to class 10th. All students can return their books once they done!

It was in practice earlier in Karnataka state. But now that has been dropped. IMO, it will reduce cost and more importantly we can save lakhs of trees.

An simple idea to create low cost toilets in rural India

SBI and its associate banks has nearly 31 Cr savings bank accounts. If they deduct weekly 1.00 (One rupee) from each account, they can collect 124 Cr rupees monthly.

If they donate this amount for building low cost toilets in India, then we can build 82,000 toilets / month. To build a low cost toilet, it would cost ~12K.

Source:

http://www.thehindu.com/business/Industry/sbi-to-hike-minimum-balance-for-savings-account-hit-31-crore-people/article17417909.ece

https://www.giveindia.org/p-10147-sponsor-a-low-cost-toilet-for-a-poor-family.aspx