How do you use software architecture to facilitate testing and quality assurance?

Good architecture designs are driven by Test Driven Development. Testable code is easily changed, so when we design it as we go to be "testable" we can implicitly change our architecture rapidly. Except in rare cases it's important to start out as a modular monolith, which can later be easily split into micro-services when the boundaries become clear and have settled. This makes it easier to test, and requires much less refactoring. Refactoring a distributed system is very time consuming, while refactoring a single codebase is simple, quick, and easy. As the boundaries become clear, we can start splitting into separate services very rapidly.

An ideal proposed architecture conveys the proposed solution to the entire development team, and each member implements it per the architect's intent. Once the solution is clean and accurate, testing becomes an enjoyable process, ensuring the development team's creativity continues to meet the customer's needs - my 2 cents!

Test Levels & Test Type Unit Level - Static code analysis, Review, Unit Test Component Level-Component Test (Mock) System Level-Integration Test Product Level-UI Automation, Functional Test

Good software architectures are evolutionary and therefore facilitate testing by adding fitness functions. The fitness function's job is to assess objectively the architectural decisions that were/are made. Fitness functions are tightly coupled to architectural reuqirements. For example, you have a requirement that a compensating action executes within x milliseconds. You would then write a perfomance test for that. Another example, the software is required to anonymize data. You would then have a fitness function or set of functions that checks for anonymization. Even larger things can be captured for fitness: your requirement is that the code is maintainable. You have a fitness function set of linters, code coverage and unit tests.

An architectural style brings out the knowledge and research expertise of the architect to solve the customer's needs, keeping in mind the development team's capabilities. The patterns are intended to solve the problem and should not be leveraged just because it sounds cool. Microservices, Mini Services, or Macro Services might be an ideal pattern for a problem, depending on the customer's need and the turnaround time requirement based on the development team's capabilities. I suggest breaking patterns if required to provide an ideal solution and path to the solution - my 2 cents!

High Level or Product Level Design pattern. Consider in Beginning of Development cycle(Inception, Elaboration stage) Eg: Layer Architecture Loosely coupled Component Integration : Pub Sub MVC (UI & Data layer separation)

An architect should guide the team towards investing the right effort towards testing without overdoing it! Blackbox and automation testing would be a great place to start validating the end-to-end system being built first and ensuring unit tests are built as and when functionality is being developed. Many times unit tests are seldom maintained as the product evolves. Let's ensure the QC team is creatively validating the solution without repeating each test in a mundane manner for every release - this is my humble request to the developers and architects :-) - my 2 cents!

It is important to understand the relative priorities of the underlying quality attributes because most times, they tend to conflict with one another. This will then help with testing priorities and use-cases.

Over the years we see some established patterns regarding software architecture and testing. Modular software: Breaking down a system into modular components helps in isolating different functionalities. This makes it easier to test individual modules independently, reducing the complexity of testing. Clean API and interfaces: Well-defined APIs and interfaces make it easier to create automated tests, as they provide a stable contract between different components or services. Inversion of Control: Injecting different implementations to the consumer class or method allows us to mock external dependencies and allow us to test in isolation. CI/CD: Automating the pipeline ensures tests are run constantly, allowing early detection of issues.

Practical software architecture enhances testability and quality assurance by incorporating modularity, observability, configurability, and scalability. It enables component testing, monitoring, and robust automation of testing processes. Such architecture supports the creation of high-quality software, making it easier to test, maintain, and adapt to varying loads, ensuring robustness and performance. Integrating these features from the design phase helps avoid costly redesigns and meets quality standards.

Design Testability is important for Quality Attributes and functional req. While Design component consider below to achieve testability -Visibility/Observability -Controllability of component. -Operability of component

Architectural analysis and evaluation are crucial processes that ensure a software architecture meets stakeholder requirements throughout the development lifecycle stages. These assessments serve several purposes: 1. Designing a robust architecture by identifying potential dependencies and interfaces. 2. Allowing ongoing adjustments in response to emerging challenges or requirement changes. 3. Confirming compliance with requirements. 4. Supporting thorough testing and quality assurance. 5. Facilitating informed decision-making for a stable, efficient, and maintainable software system.

Architectural analysis can be a great way of identifying gluing points where most disconnects can occur. A unified testing strategy can be defined in a way that when different parts of the architecture are developed in isolation it does not result in large flaws down the line.

Architectures should continuously evolve over time. We do very rough designs up front, with no commitment to them, and we iteratively evolve the architecture as the software is developed and maintained. This removes a lot of our guess work, as we strive to solve problems for the business in the moment, based on what we know now. This is a very core part of Agile, and is one of the reasons agile organizations are so successful at delivering and maintaining software. This saves in the area of wasted effort, as we only implement what we know we need, instead of trying to predict architecture before we have enough information.

Architecture evaluations : Quantitative & Qualitative. complement each other. Quantitative -Code analysis & Matrix, Dependency -component boundary, Public Interface access Qualitative -Scenario based & Experience based Architecture Review -> Check Architecture can facilitate future scenario. ->Identify Risk & suggest mitigation -> Productivity, Complexity -> Review business' driver requirements -> sufficient documented to maintain -> Design principles & KDD for maintain Architecture

Testing is something that literally happens starting on day 1, continuing to day N. We start by deploying a "Hello World" application that asserts with an automated test that "Hello World" was output to the user. We then iteratively change the software, rearchitecting as we go, adding tests as we go, testing manually as needed, throughout the process of Continuous Delivery or Continuous Deployment, with the latter being preferred.

Testability is Biggest Challenge. Tools & Skill to use them Design Test case for various Test Levels. Best Practice Unit test, Dependency Injection, Mock dependency, Unit Test & Integration test = 100 % code coverage Requirement to Test Case Traceability