How do design patterns improve microservices architecture?

Design Patterns are the result of the collective wisdom of software architects, who over the years have created re-usable blueprints of software design. While the use of design patterns assist in avoiding common pitfalls, they should not be over-used. Inexperienced developers tend to use design patterns even for simple tasks, which may introduce inefficiencies. The knowledge of which design pattern to use - for which problem statement comes only from experience. One should consider design patterns only as a “toolbox”, and developers should use their creativity and thinking to design their software.

The Strangler pattern is an architectural approach employed during the migration from a monolithic application to a microservices-based architecture. It derives its name from the way a vine slowly strangles a tree, gradually replacing its growth. Similarly, the Strangler pattern involves replacing parts of a monolithic application with microservices over time. In order to implement strangler pattern, we need to follow 3 steps that are as follows: Transform Co-exists Eliminate

Design patterns have indeed proven track record and often shared within team members. Just as design patterns can help us get started, it can also run us into restrictions that aren't questioned early on.

They represent best practices evolved through years of experience in software development and are used to address recurring design problems efficiently. Design patterns provide a template or blueprint for how to solve a problem in a way that has been proven to work, which can then be adapted to suit the specific context of a project. They cover various aspects of software design, from creating objects to defining object relationships and facilitating communication between objects. In the context of microservices architecture, design patterns help in managing the complexities of developing and maintaining a distributed system.

Design patterns are symphonies that form a masterpiece. realistically beyond just the ability to keep code clean, organized and extensible they are literal superpowers that allowed developers to produce high performing modular web applications that also integrates super well within and outside the organizational boundaries. eg, consider pairing a strategy pattern, where a developer keep the classes that implement a strategy interface in a registry. Now pair this up with a explorer, where the explorer will dynamically locate all the classes with some metadata and form a strategy registry at the runtime. Won't that not just create super modular and extensible code within but also for external contributors ?

Creational patterns help identify a starting point for the data as it evolves and flows through the system. Perhaps the roots come from religious views but it seems to help a person figure out a starting point. Technically helps create and maintain testable code.

Creational design patterns play a significant role in enhancing microservices architecture by streamlining the process of creating service instances and managing their lifecycles. These patterns, such as Singleton, Factory Method, and Abstract Factory, provide flexible and efficient ways to instantiate services, which is particularly important in a distributed environment where services need to be scalable and independently deployable. For instance, the Factory Method pattern can be used to create a service or a group of related services without specifying their concrete classes, allowing for greater flexibility and decoupling.

Creational pattern ensures the single responsibility design principle. It makes the programmer to implement the objects definition to be more reliable to make it reliable in other patterns

Creational patterns can enhance any design architecture, not exclusively microservices architecture, by providing an efficient mechanism to identify the main resource for the creation of any object in object-oriented programming. Regarding microservices architecture, I see that some creational design patterns, such as the Factory Method Pattern, can help in "Consistent Object Creation" by providing an interface for creating instances, supporting consistent object creation across services. This is particularly useful if the business logic requires a common structure initialization for multiple sibling services.

Consider the flow of raw obfuscated object on some boring logging service. If clearly designed, the service will assess the object and enhance or escalate (e.g. uptime threshold ) with appropriate flagging. Reviewing patterns every 6-12 months is helpful for objectivity.

Structural design patterns are instrumental in improving microservices architecture by organizing and managing relationships between services, ensuring the system is scalable, flexible, and easy to maintain. These patterns, such as Adapter, Proxy, and Composite, help in building well-structured and organized microservice systems. The Adapter pattern, for instance, allows services with incompatible interfaces to communicate with each other, promoting interoperability and reducing the impact of changes in external services. The Proxy pattern can be used to control access to a microservice, adding a layer for security, logging, or lazy instantiation, which is crucial in a distributed environment.

Let us say we have a producer and some consumers. The Producer moves to a new version (v2) i.e. the format of the produced data is now different. Should we implement an adaptor from v2(new) to v1 (old) OR place data in both v1 and v2 formats in a packet OR introduce v2 on a different topic/queue OR request consumers to migrate OR define interfaces in an extensible way? This should be the first step: identify the problem and the different solutions, including any relevant patterns. Debate these, not the patterns.

Structural patterns and the Microservices architectural pattern share a common goal, emphasizing the modularity of code by breaking down solutions into multiple standalone services. Implementing structural patterns in Microservices is akin to adding a cherry on top of the solution. The Bridge pattern, in particular, can play a significant role in achieving the 'Separation of Concerns.' By separating abstraction from implementation, it allows services to evolve independently, ensuring flexibility and adaptability as the system grows.

This is purely related to semi-autonomous policy creation. Such patterns help with designing rule rule-based execution framework.

These patterns focus on how objects and services communicate and cooperate. The Strategy pattern, for instance, allows the definition of a family of algorithms, encapsulating each one and making them interchangeable; this is particularly useful in microservices for implementing various business logic or policies dynamically. The Observer pattern enables a microservice to publish changes to multiple other services, which is beneficial for event-driven architectures commonly seen in microservices, fostering asynchronous communication and reducing coupling. The Chain of Responsibility pattern can be used to pass requests along a chain of handlers, allowing multiple microservices to process a request in sequence or conditionally.

Chain of responsibility is a great pattern that can be employed to create rule engines that are not just flexible but also less error prone consider this DSL I created prop: users type: array items: type: object properties: first_name: type: string required: true status: type: string required: true enum: [active, pending, inactive] Chain of responsibility allow us to implement a base validator on base types like string and then each base validator sets the next sub validator, now in places where i validate if an entity is string I call validate() on baseValidator and that sets the next validator for any of sub types like enum, and the sub validator call validate() in a chain.

Start by analyzing the individual components and interactions within your microservices system, identifying areas where patterns can enhance scalability, maintainability, or communication. Use creational patterns like Factory Method for service instantiation, structural patterns like Proxy for managing service access, and behavioral patterns like Observer for efficient inter-service messaging. It's crucial to ensure that the chosen patterns align with the principles of microservices, such as loose coupling, high cohesion, and independent scalability. Implement these patterns consistently across the system to maintain a coherent architecture.

This is already a team effort. Engage with others that design or own the services. Provide options and value. Be the owner of such knowledge in case others need to add/modify policies, data flow, chaining. Don't over-engineer because you think you did little!

The object communication and viewpoints relations are to be obtained. The pattern should ensure the flow of data across viewpoints and the defined architecture to be the one that meets the design objective

Yes I created a microservices API aggregator that used the strategy pattern with strategy registry and automatic strategy exploration. I used decorator pattern to label functions as @Route which allowed me to set properties of an external API route to the decorated function and I used the decorated function to perform pre transformations on the request before calling the external API. Now I used explorer to get all the functions with @Route decorator and created a metadata store so later my connection runner just had to take a name into input and it used to get the entire context of function from the metadata store. I used strategy pattern to authenticate external APIs using various mechanisms like Oauth2, Digest, X-API-KEY etc

In a project i was part of, we had a firehost of data coming from GPS based telematics systems on cars. Building a queue provided challenging so we created a series of flows based on volume to provide updates in a reasonable way. Analytics on a firehose is challenging. After all, people don't want massive dashboards with lots of moving parts. Design for yourself, design for others.

One thing we should all remember is that engineers are human too. ADHD is real and the search for truth is unchecked. Over engineering happens when users and engineers are far apart and layers of management/owners/stakeholders/labels is full of fluff. We have come from monolithic to loose (SOA) to monolithic angular/next and to microservices mayhem. Software ought to be kept in check and at times called out for making things worse. Ask why the service is needed and weight rationally and objectively instead of appeasing to DevOPS gods. I could be wrong, I'm just a human.