January 31, 2023

Monolithic To Microservices Migration For Modern Applications

Monolithic systems have traditionally been employed alongside legacy systems, finding utility in the development of straightforward programs and proof-of-concept applications. Nevertheless, as the complexity of applications grows, businesses are now prioritizing adaptable and scalable software solutions.

The migrating from monolithic to microservices is evident in the tech industry, with approximately 63% of companies, including major players like Spotify and Amazon, embarking on migration journeys. Recognizing the need for flexibility and scalability, forward-thinking tech enterprises are exploring this transition.

To execute a seamless monolithic to microservices migration, it is crucial to formulate a well-defined and achievable strategy that takes into account the distinctions between monolithic and microservices architectures. This strategic approach is essential for navigating the evolving landscape of software development and meeting the demands of modern, intricate applications.

What is Monolithic Architecture?

In a monolithic architecture, all operations, data storage, and migration from on-premise to the cloud are managed by a single codebase. Typically, monoliths include a client-side user interface, a server-side application, and a database. The server-side application is responsible for receiving and processing requests, executing domain logic, retrieving data from the database, and presenting it to the user interface of the requesting client.

What are microservices?

Microservices architecture, or simply microservices, is an alternative application development approach. Instead of a single, monolithic structure, it constructs a larger application from multiple modular services that communicate through APIs. These independently deployable services, designed with specific business goals, operate with loosely coupled components and utilize separate databases and coding.

In a microservices setup, each service is typically managed by an individual team. This enables independent processes for updating, testing, deployment, and scaling for each service, contributing to a more manageable level of complexity.

Need Of Migration From Monolithic To Microservices

Scalability: Microservices allow for independent scaling of individual services based on specific needs. This flexibility ensures efficient resource allocation and cost-effectiveness.
Agility and Flexibility: With microservices, development teams can work independently on different services, enabling faster development cycles. This agility is crucial for businesses to adapt to changing requirements and market demands.
Enhanced Fault Isolation: Isolating services means that if one service fails, it doesn’t necessarily affect the entire system. This improves fault tolerance and makes it easier to identify and address issues.
Technology Diversity: Each microservice can use the most suitable technology stack for its specific task. This allows for technology diversity within the overall system, promoting innovation and the use of the best tools for each job.
Ease of Maintenance and Updates: Updating or modifying a specific microservice is simpler compared to making changes in a monolithic system. This ease of maintenance reduces downtime and facilitates continuous integration and continuous deployment (CI/CD) practices.
Improved Fault Tolerance: Microservices promote fault tolerance by allowing failures in one service to be isolated from others. This results in a more resilient and reliable system.
Team Autonomy: Individual teams can be assigned to develop and maintain specific microservices, fostering autonomy and specialization. This can lead to increased productivity and expertise within each team.
Scalability of Development: Microservices enable parallel development by different teams, speeding up the overall development process. This can be especially advantageous for large and complex projects.
Easier Adoption of New Technologies: Since each microservice operates independently, it’s easier to adopt new technologies for individual services without affecting the entire system. This facilitates the integration of the latest tools and methodologies.
Improved Fault Detection and Isolation: Microservices typically have well-defined interfaces and communicate through APIs. This makes it easier to detect faults and isolate issues, leading to quicker resolution of problems.

While microservices offer numerous benefits, it’s essential to consider factors such as increased operational complexity and potential challenges in communication between services. The suitability of microservices depends on the specific needs and goals of a business.

The Move to Microservices

As VUCA dominates the world and digital transformation with SAP & SAP CX Solutions becomes imperative, development agility becomes essential for enterprise businesses across industries. Microservices are a response to this enterprise need and provide the agility and responsiveness required to navigate today’s business environment.

Microservices allow enterprises to develop a complete product from a collection of small, isolated services. Each of these services owns its data, is isolated from each other, independently scalable, and far more resilient towards failure. These services integrate seamlessly and deliver a system that is more flexible and easier to maintain, update, and scale than monolithic applications.

Along with this, microservices also render themselves well to APIs. APIs have become instrumental in helping enterprises drive product modernization opportunities and deliver robust, reliable, and scalable products into the market faster.

Microservices Architecture – The Backbone of Products Today

Microservices demand an inherent change to application architecture. This architecture allows developers to increase development velocity and scale products faster. They can drive incremental product modernization as well as horizontal and granular scaling. Developers can also take advantage of the modern software development ecosystem made up of technologies such as containers, cloud, Serverless cloud computing , DevOps, etc.

The microservices architecture splits the application into smaller, interconnected services instead of a large monolith. Each microservice can be considered a small application in itself and has its own hexagonal architecture that contains the business logic along with various adapters. Each service has its database schema and does not have to share its database schema with other services.

This architecture is very versatile and can be designed in different patterns according to the business needs, making it well-suited for today’s enterprise demands.

Choosing the Strategy to Migrate Monolith to Microservices

Successfully migrating from a monolithic architecture to microservices hinges on selecting the appropriate migration strategy. One viable option is the “Strangler Fig” method, where microservices gradually replace components of the monolith over time. This incremental approach minimizes risks associated with a complete overhaul, preserving existing functionalities while introducing microservices’ benefits gradually. Another effective strategy is the “Parallel Run” or “Rewrite” approach, involving the development of a new microservices version alongside the monolith. The switch occurs once the new version is ready, minimizing downtime and providing a clear transition point, albeit requiring careful synchronization to prevent data inconsistencies. Organizations may also opt for a “Hybrid Approach,” combining multiple migration strategies tailored to specific components or modules, providing flexibility across different parts of the application. Regardless of the chosen strategy, a meticulous assessment of the current system, strategic planning, and a well-executed phased approach are essential for a smooth and successful migration to microservices.

Monolithic To Microservices Migration – Step By Step Guide

Microservices can be used for anything. Some might use it to build macro services or a well-defined system design. Others might use it to modernize business processes. Getting an understanding of the concept and how it can be of business use is essential to leverage its benefits.

Identifying the Technology Stack

Microservices can be exciting for developers since it gives them a lot of flexibility in choosing their tech stack. However, it is key to remember that this has to be done for each service within a microservices architecture. Standardization issues, for example, could occur if the services are heterogeneous.

There could be people contributing from different teams to develop individual microservices. It can be challenging to manage the tech stack if all the teams use different ones across the application.

Taking a balanced approach and selecting a tech stack that meets the current and future needs of the application is an important consideration point here. Identifying the business vertical, process, compliance, and industry-specific needs becomes crucial in selecting this process and hence requires tech expertise.

Degree of Independence

Microservices promise independence. But how independent do we want the services to be? The choice here has to be made between:

Each service is completely independent, with its own UI and database
Share some components between the services, such as the database

The first option is an instance of an extreme microservices architecture where services are entirely decoupled and share nothing. Each microservice chooses the database that best addresses its requirements. However, ensuring that all data stores are in sync and consistent is challenging.

The latter option makes it easier to enforce standards across all teams and ensure data consistency across all services. However, this also means that services are not entirely decoupled.

Choosing the right approach becomes critical here.

Managing Operational Complexity

Microservices introduces a little bit of operational complexity as it demands a close look at aspects such as the existing infrastructure and its need to be scaled up or down to meet the application needs.

Creating a load balancing and scaling strategy also are important consideration points. Determining whether to scale all services or just a subset when there is a spike in demand is essential.

It is important to define the growth scale of the microservices. Identifying the qualitative growth scale determines where the service fits into the overall microservice ecosystem and the key high-level business metrics its impacts.

Configuring and maintaining microservices monitoring and identifying automation opportunities are also essential to manage operational complexity.

Refactoring the Underlying Data Structures

This is perhaps one of the most complex parts of migrating to microservices and needs careful consideration. Getting the data design right, identifying the data storage and management needs, and ensuring that all databases work together to support an application is essential during the move to microservices.

The Role of Expert Product Development Partners

Moving from a monolith to microservices architecture makes great sense today, especially as technology trends like serverless, cloud-native, APIs, etc., are becoming crucial to leverage. While there are a few complexities to navigate when moving to microservices, the journey becomes smooth when there is the support of expert product development partners.

Technology and domain expertise complemented with development and implementation experience can help enterprises make those key considerations and weigh the several pros and cons. With assistance from a reliable partner, enterprises can even shift hyper-complex monoliths to nimble, agile, and infinitely more flexible microservices without worries about the hiccups that can come along the way. Connect with us to learn more.