Microservices are becoming increasingly popular these days. A microservice is an architectural approach to software development that regards a software application as a series of independent services. And all of these services are connected using well-defined APIs, which also enables them to communicate with each other. Indeed, businesses can effectively leverage microservices best practices to offer a large array of benefits, but building microservices comes with its own set of challenges.
In this article, we are going to discuss some common problems you might face during the development and usage of microservices and how to solve them.
Microservices are just one type of architectural style used for distributed computing. Here, the application is formed by combining various independent services that are capable of communicating through a network. When a customer wants to use this service, they must know the specific location of the network. In the case of one available location, there wouldn't be much of a problem. But if the location keeps on changing, then we have got a very complex problem at hand.
To resolve this issue, the designers have to install a service registry along with the database of every service network location. Service discovery and registry could also be accomplished using a third party with a common registry. A common registry will enable the customers to quickly discover the network locations of services. Such solutions are already implemented in the Kubernetes service and Netflix Eureka service registry.
As we already discussed, microservices are the combination of loosely connected multiple services. These services are rendered to a large number of customers. Not every customer would want the same thing in the same way. Everyone might have different requirements. For example, for a web application, you will need a set of information that is grained coarsely, but for a mobile application, you need a set of information that is grained finely. And things might get worse if these services are implemented with protocols such as REST and JMS.
To simplify the process of accessing these different services, you might need something called a unified access mechanism. This mechanism can be built by utilizing a simple API gateway as a single-entry point for every service associated with the microservices architecture.
To access the services, the customers would have to call the API gateway. Then the API will route the users to their requested services. On top of that, the API gateway also offers additional services like security metering, aggregation of services, and more. You can see such a mechanism implemented in Apigee, Amazon API Gateway, and Spring Cloud Zuul.
Security will be one of the main concerns no matter what software services you are using. The same is true for microservices. To make your services secure, you can apply a simple centralized authentication service. It will ensure that all the customers who want to utilize the microservices are authenticated first. On the other hand, every single service should be charged with authorizing their customers as well.
To fulfill some of your needs, only a single service in microservices architecture can be enough, but other times, it may require multiple services to work together to meet your demands. In microservices, every service has its log. It would be overwhelming for a developer to go through these logs manually, aggregate all the services, and then troubleshoot the bugs. The alternate way to accomplish logging and debugging is to play it smartly. All you have to do is to use a simple logging service every service will be connected to for writing their logs. Some common examples of such technical implementation are Kibana, Logstash, and Elasticsearch.
Similar to logging and debugging, configuration gets complicated when you are working with microservices. Because every service is independent in the architecture, and they have to be configured individually. Here, things can get really difficult if you have to run the app in different environments without making any changes to it. Configuration can vary from network locations to DB credentials to environment variables and so on.
One way out of this jam is to enable centralized configuration services wherein every service is connected with this service to configure itself. Now this service must have a common configuration repository that allows the centralized service to read the configurations of all the services. One example of such a system is Kubernetes configmap.
Another challenge you might face is that your services can't work together in sync to fulfill your needs. One possible cause for that is a lack of a communication medium between various services. There are three ways to resolve this issue and establish communication among microservices:
- Service mesh
- Point-to-point using API gateway
- Using a messaging event drive platform
Testing the services can be challenging when there are a lot of them to deal with. If you want to conduct a unit test or an integration test, you can do it by either mocking the microservices individually or mocking the dependent APIs available for the test. You can conduct various mock tests with the help of Cucumber, BDD, WireMock, etc.
There can be a lot of problems when you are dealing with microservices, and we can hardly get to address a few. But the ones we discussed here are some of the common problems that you might face while developing or working with microservices. We hope that this article can be helpful to you in overcoming the microservices challenges.