If you are living in the same world as I am, you must have heard the latest coding buzzer termed MICROSERVICES — A lifeline for developers and enterprise scale businesses. Over the last few years, Microservice Architecture emerged out to be on top of conventional SOA(Service Oriented Architecture). This much more precise and smaller architecture brought in many benefits along with it. Enough to make the business more scalable in a fly by paralleling development, testing and maintenance across various independent teams. Considering how different this approach is from the conventional monolithic process, the testing strategies that apply are also different. With different testing strategies emerge different testing challenges.
If you are not already aware of what a microservice architecture is or how it could be tested? Then refer to our blog regarding How to test a Microservice Architecture Application.
By far everyone in the tech world is aware that Microservice Architecture is useful in delivering a more responsive and agile application. Some major organizations such as Netflix, Nike, Facebook etc. have backed their performance on the basis of this architecture.
Key challenges for Testing Microservices:
Integration Testing and Debugging
To write effective integration test cases, a quality assurance engineer should have thorough knowledge regarding each of the various services that a software is delivering. Analyzing logs across multiple microservices can be very twitchy and mentally taxing.
With so many independent teams working simultaneously on improving different functionalities, it becomes very challenging to coordinate the overall development of the software. For instance, it is tough to spot out an idle time window for extensive testing of the entire software.
Decoupling of Databases
Each microservice helps to establish a single business capability and should have its own separate database. However, if that isn’t feasible then you may also know that in some applications, there may not exist a necessity for decoupling database. So a sound evaluation is required to judge which microservice needs decoupling and which doesn’t?
Re-Architecturing a software product
It can be very tiresome for a software architect to redesign the working of an application in accordance to microservices, especially if we are talking about an enterprise with gigantic and compound systems.
Complexity of a software is directly proportional to the number of microservices that the product is either delivering or adding.
If you are transitioning from monolithic to microservice architecture then large number of tiny components are bound to be generated. These components should communicate consistently. Performance tracing for business transactions could turn out to humongous.
Difficult to visualize after effects
Involving numerous distinctively functioning teams, requires a top notch interface for communication. If all interfaces aren’t properly updated in a software then it may doom the collaboration. It becomes very strenuous to consider the after effects of bringing any enhancement in the existing communication platform.
It is true that microservices provide developers the freedom to not be dependent on a specific programming language, increasing their flexibility. However, you would have to face the hassle of maintaining multiple libraries and database versions.
Cleaning up software libraries
As quoted by Fowler-Rigetti, “You have some script running on a box somewhere doing God knows what and nobody wants to go clean that up, They all want to build the next new thing.” With variety of developers from different microservice teams, there are numerous ways for performing a single action. Deploying custom scripts from different languages it happens very often that we forget about a certain piece of code. This results in recreating that feature by some other custom script belonging to some other language. Effective maintenance and management is needed to overcome this.
Having great number of microservices at your disposal it becomes vital to prioritize these services in terms of resource allocation. You cannot afford to launch unnecessary number of resources in a microservice team that is responsible for a relatively small functionality.
How to overcome such challenges?
- Specific API endpoints- API endpoint must be provided by every microservice in order to communicate either synchronously or asynchronously with other microservices. These endpoints work on http verbs say get request, post request and delete request etc. Each Microservice has to let the other services know exactly what pattern should be followed, for appropriate routing of the request? Usually it is a REST endpoint for facilitating synchronous communication but it could also be a WSDL endpoint for facilitating asynchronous communication. The formats of these APIs have to published to other microservice teams so that they know how to connect to your microservice.
Once the routing is published and passed on to every microservice team, then a standardized communication takes place among the system. Boosting the efficiency of the integrated software.
- Every microservice is responsible for its own data model. Ideally, each database model should be 100% decoupled from another. The idea behind this is to know what persistence model is needed for the team working on facilitating a single microservice?
- Autonomous selection of technically sound staff for every microservice. Hiring effective developers, testers, quality analysts, business analysts and project managers will definitely bring you the key to success.
- Not all microservices are bound to provide some form of UI. Some are there to support the integrated interaction such as middleware team.
- Standardized development practices along teams calls for a bigger investment on platform basis. This is where cloud based providers come into the picture like AWS(Amazon Web Services), Heroku, Google cloud etc. Therefore, if you are planning a small scale organization and not envisioned to go for scalability anytime soon then you are better off microservice Architecture.
- Make it a necessity to correlate calls with the help of various methods like IDs, tokens or headers. Also, when logging to locate a bug we need to make sure about correlating events across all platforms to avoid ambiguity in this stateless, independently distributed architecture.
- Devops need to be more integrated than they ever were. Security needs to be more robust and unbiased as the diversified structure provides hackers the opportunity to hit the soft target of your system.
- Fault tolerance should be optimized and consistent monitoring must be performed. Effective use of caching would also help to speed up response time by reducing the number of requests that the software will aim to meet.
- Also, if you are planning on developing a feature to aid your respective microservice. You need to make sure that it doesn’t affect the functionality that is being delivered by some other microservice team. Your enhancement must support the entire pre-existing functionality of the application.
You need to have excellent monitoring tools to display the working of your software. Effective logging and documentation may seem exhausting but are indispensable for the software maintenance and enhancement. We don’t intend to criticise microservice architecture, however we want you to be aware about them in detail before it gets deployed into your organization. Microservice architecture will definitely boost the scalability of your business development, bringing a top notch product in the market. All you need is a little precaution regarding the pros and cons of its implementation. Remember, prevention is better than cure!