WeatherStackApp

This Weather App displays the current temperature and wind direction for location Mumbai , by default. The app fetches live weather information from WeatherTrack and presents it using a clear and responsive user interface.

Features

• Real-Time Weather Data: Fetches and displays the temperature and wind direction for Mumbai. (To get for other location, for now, we need to update the code)
• MVVM Architecture: Utilizes the Model-View-ViewModel (MVVM) pattern for a clean and testable codebase.
• SOLID Principles: Built with SOLID principles to ensure scalability, maintainability, and separation of concerns.
• Comprehensive Testing: Includes both unit tests and UI tests for reliable performance and quality assurance.

Architecture

The app follows the MVVM architecture, ensuring separation between business logic, UI, and data management:

• WeatherModel: Represents weather data from WeatherTrack. Currently, we are using only Temperature/Wind Direction and Location Information from WeatherTrack JSON Output
• WeatherViewModel: Manages data fetching, processing by Connecting with Network Client (NetWorkClient protocol), and binding to the UI.
• HomeScreenView: Displays weather information and fetches whenever the HomeScreen is loaded

Code Quality

The app is built according to SOLID principles:

• Single Responsibility Principle (SRP): Each class and component has a single responsibility. HomeScreenView: Responsible for Displaying Weather Info for Mumbai Location (currently, hardcoded) AboutScreenView : Responible to Provide App Description TabBarScreenView : Responsible to Handle TabBar style Navigation based upon selected TabBar
• Open/Closed Principle (OCP): WeatherModel can be extended for adding more info from WeatherTrack Service
• Liskov Substitution Principle (LSP): NetWorkClient is used to abstract only required method fetchData. This protocol can be used to create other Network Clients
• Interface Segregation Principle (ISP): HTTPClient is the interface which segregated with only required method.
• Dependency Inversion Principle (DIP): MockHTTPClient is created from protocol NetworkClient and can be replaced with HTTPClient to achieve XCTest execution with Mock Data

Network

HTTPClient is the class responsible for fetching data from api "https://api.weatherstack.com/current?access_key=\(api_key)&query=\(location)" MockHTTPClient class creates mock publishers for providing success and failure json response to ViewModel publishers.

ErrorHandling

When there is a case of failure we will be showing the alert for the user with retry option upto 3 times.

Testing

Unit Tests

The app includes XCTests for:

• WeatherViewModelTest: Creates a WeatherViewModel from MockHttpClient and fetches data from overridden method of weatherPublisher. Executes the test by parsing weatherInfo.json with weather mock data of city Hyderabad. Also, tested failure case of decoding the content by passing invalid json object from weatherInfo_Failure.json file.
• WeatherStackAppUITests : Executes test case of UI Elements of HomeScreenView/TabBarScreenView/AboutScreenView