Microservices become more and more popular in software development. Now, it is a trend because of a lot of advantages: flexibility, agility, scalability. That’s why this architecture reacts to changes very fast. Also, it is customer-centered. Today, we are going to talk about microservices. We want to compare it to monolithic architecture and describe the main advantages and disadvantages.
Based on the information in this article, you can make a decision about what type is better in your case. Monolithic vs Microservices: what is better?
What is Monolithic Architecture?
What does “monolithic architecture” mean? What place does it take in the IT-sphere? Let’s describe this technical term in detail.
It’s a word meaning that an app was created using one code block. All the parts of the code use the common space in the memory and resources of the device. At the core of this app is a solid block of code like a monolith.
This approach is checked by time, and software developers have been using it for many years.
The basic principles in the core of a monolithic type of development:
- One database stores the entire application. It doesn’t have separate modules, all of them are connected to a single system. Yes, code can have classes and packages but they are not autonomous.
- The code of an application is packed into a single version as soon as it is handy to be released. When you need to make some small or significant changes, you need to stop the application, make changes, and restart it. It takes a lot of time.
- Parts of a monolithic application can communicate with each other without problems. They use internal procedures for it.
- Every iteration makes an application bigger. It makes it less friendly to people who want to manage this app.
- If you want to scale one component, you need to scale a whole app. It is inconvenient but you need to do a lot of unnecessary things.
These features have a lot of positive sides, but they also have negative aspects. Let’s start with advantages of the monolithic architecture. Their number is significantly bigger than an average person thinks. Just read the text below, and you will be sure of it.
As we said previously, this architecture is time-tested. For this reason, for many people in monolithic vs microservices competition, the first one wins. That’s why almost all applications that were successful are monoliths (with exceptions but they always are). People who like microservices usually say that monoliths are not modern and are a bad idea. At the initial step of project realization, there isn’t any need to use microservices. Monolithic applications are better in some cases. Let’s describe the basic benefits of it:
- Simplicity in the process of creating this application. Every developer knows this architecture. It is a standard method of creating different types of applications for a period of time, which is very huge for a lot of people. It is understandable for everyone who wants to create an application. It is important both for beginners and professionals that know how to actually create software. The process of development is simple. A lot of different instruments for creating this type of application, servers, and interfaces are compatible with this type of app.
- Simplicity in deployment. If you want to deploy the application created with this architecture, it will be very easy for you. This process includes only one step: copying a single archive to a server. That’s all.
- Simplicity in testing. You only need to deploy an app one time and all features will be available. You don’t need to do a lot of additional things to test an application. It is really convenient, isn’t it? You don’t need to wait for additional dependencies, and this fact makes the process easier, which is great.
- Simple sharing. If you want to share the code, you can do it without any trouble. The main reason for it is in how it is stored. It exists in one base. It makes sharing easier across all the stages of the development pipeline.
- Friendly to IDE. You don’t need to look up the best development environment. They can be set up for monoliths without additional spending of time.
Monolithic architecture has a lot of advantages. But let’s describe disadvantages that make this application not flexible and can bring some problems in development.
A quantity of disadvantages is also great. It makes this architecture fit for a few tasks. You need to understand what to do and use the appropriate architecture in your application. Let’s describe the cons of monoliths in detail:
- It is difficult to understand how applications with this architecture work and make some changes in the code. It is hard to understand a certain part of the app and what dependencies there are in this app. This is significant for new workers in the company, who need to adapt to the team and understand the algorithms of applications. If the app is complicated, it is difficult to make proper changes according to the task.
- Limited agility. If you want to modify the smallest part, you need to deploy the entire application again. When one person is working, others need to wait to make changes in other parts. Due to this unpleasant fact, the team’s agility and flexibility become much lower.
- A lot of unnecessary problems. For example, you can face troubles in delivering, deployment, or integration. Some applications need to be updated a lot of times per a certain period of time. If we talk about monolith, this task is really impossible because you need to deploy an application every time you want to perform a change.
- Low speed of work. Codebase size is huge. It loads IDE too much. It is associated with a longer time of development and starting the application requires a lot of time.
- Unreliability. If one bug appears in the system, all the applications can be stopped.
All of these disadvantages are important reasons why a lot of people select microservices architecture. Let’s say some words about it.
What is Microservices Architecture
Today is the era of mobile devices. Today, customers want their providers to be always available from smartphones or tablets. For this reason, mobile applications became popular. Companies also need to supply quality mobile software.
To meet this need, software needs to be extendable and able to exchange data between each other. It isn’t possible without an API. It is a reason why microservices have been spread so fast. The classic monolith architecture isn’t enough to realize this task.
Microservices is a set of services that have weak connections with each other. It makes this system flexible. However, it is not possible to use it in all cases.
What are the key features of this type of architecture?
- Code of every part is isolated from others and has its own part of memory.
- There are more complicated connections between services.
- The size doesn’t become bigger after iterations.
- Every component can be scaled independently. It is the most important feature for modern applications.
- It is possible to use a shared library.
- Continuous delivery can be easily performed.
This architecture is flexible and has a lot of features. But it doesn’t have only advantages. It has disadvantages too. Let’s consider the pros and cons of the microservices architecture in detail.
The architecture of microservices is well organized. All of them are obvious. Every block tries to complete its own tasks. They can be recombined and their configuration can be changed without corrections to the entire structure. Let’s consider the advantages of microservices compared to monoliths:
- Diversity. Developers can choose any programming languages they want. It is possible to mix different tools in one solution. It also requires rewriting some functions using more modern tools. This choice opens a lot of additional opportunities for developers.
- Easy to understand and evolving application. Due to the small codebase, you can work with one module. It makes it more understandable and easier to develop. You don’t need to know how other parts of the application work.
- More scalable applications. If services need to be scalable horizontally or vertically, they can easily do it. Local changes can be deployed without any problems. In this case, they don’t affect other stacks and work autonomously. It is a very big advantage if we talk about the difference between microservices and monoliths.
- Reliability. An error affects only the service where it occurs. Other parts of the application work without any trouble. It makes the system safer and more reliable.
- Easiness of new technologies implementation. Microservices are able to be easily adapted to changes in the world and use the most innovative technologies.
- Flexible teams. You can have different teams for every block of the application. Some of them can be created by a couple of developers. Others need to be created by a lot of professionals from different spheres.
To sum up, there are a lot of positive sides that microservices have. It isn’t surprising that they are so popular. But we have some disadvantages that make them hard to use for some tasks. Let’s consider them.
Despite all the positive sides described above, microservices can’t solve all the problems of applications. In some situations, they can be not so easy and have disadvantages:
- They are hard for integration testing. Microservices are easy to be tested in different environments. But if you want to test the entire application, it can be difficult for you. The more modules we have, the harder integration of the services is and the more difficult it is to make the process more effective.
- There are a lot of difficulties in usage. It is hard to manage several databases compared to monoliths. You can use Docker, Ansible to solve this problem but using these tools is also associated with some troubles.
- You need a lot of time for creating separate modules instead of creating one code for an entire application.
- You need additional skills. Working with microservices isn’t for beginners. When you are only studying coding, you need to understand how monoliths work and only after that start creating different modules.
What can we say about these services? Which of them is better? Monolithic vs microservices? Yes, microservices is the more modern architecture, but it is harder to implement and you need some additional skills to do it.
Moreover, it is true that some applications are friendly for monolith architecture. If you want to have your applications be able to be extended using add-ons, you’d better use monoliths. If you want to make an application that can be fully integrated into the operating system (especially, Android) and use an API for connecting with other applications, microservices are actually the only option.
If you need to create a simple application, you don’t need to go through such difficult logic. You can create applications based on monolith architecture that works. It isn’t as flexible but it is a convenient and fast solution.