Appium is a popular open-source tool for automating mobile application testing. Understanding its architecture and components is essential to create effective mobile automation testing strategies. In this article, we will explore Appium’s architecture and its components, along with their roles in mobile automation testing. In this article, we will explore the architecture and components of Appium, an open-source tool used for automating mobile applications. Whether you are a developer or a tester, understanding Appium’s architecture can help you effectively automate mobile testing.

Introduction

Mobile automation testing has become a critical aspect of mobile application development, and with the growing demand for mobile applications, the need for automation testing tools has also increased. Appium is a popular open-source tool used to automate mobile testing on different platforms such as Android, iOS, and Windows. In this article, we will explore the architecture and components of Appium that make it one of the most preferred automation testing tools.

Appium Architecture

Appium’s architecture is based on a client-server model, where the Appium server is the central component that interacts with the device or emulator, and the client sends the commands to the server. The server processes the commands and interacts with the device or emulator using the WebDriver protocol and JSON wire protocol. Appium comprises several components, including Appium server, client libraries, drivers, and JSON wire protocol, which work together to automate mobile testing. The client libraries are available in different programming languages and offer a platform-independent interface for mobile automation testing. Understanding Appium’s architecture is essential to create effective mobile automation testing strategies.

• Appium is an HTTP server written using node.js
• The client communicates to the server using a session, where key elements of the communication process is sent with the help JSON objects. Communication is handled by the mobile JSON Wire Protocol.
• The server differentiates between an iOS request and an Android request using the desiredCapabilites arguments.
• Appium server then processes the request to the respective UI Automators as seen in the Appium architecture diagram below.
• The UI Automator then processes the request and executes the command on a simulator/emulator/real device.
• The results of the test session are then communicated to the server and then back to the client system in terms of logs, using the mobile JSON Wire Protocol.

Appium Components

Appium comprises several components that work together to automate mobile testing. The components include Appium server, client libraries, drivers, and JSON wire protocol. Each component has a specific role to play in mobile automation testing. The client libraries are available in different programming languages like Java, Python, and Ruby.

Understanding Appium Server

The Appium server is the central component of Appium’s architecture. It receives commands from the client and interacts with the device or emulator to execute the test cases. The server communicates with the device using the WebDriver protocol and JSON wire protocol. The Appium server supports different drivers to execute the test cases, including the Android driver, iOS driver, and Windows driver. The server is responsible for managing the automation session and performing actions on the device or emulator, such as installing the application, launching it, and interacting with the application’s UI elements. Understanding the Appium server’s role is critical to creating effective mobile automation testing strategies.Appium is a server written in Node.js. It can be built and installed from source or installed directly from NPM:

$ npm install -g appium
$ appium

The beta of Appium is available via NPM with npm install -g appium@beta. It is the development version so it might have breaking changes. Please uninstall appium@beta (npm uninstall -g appium@beta) before installing new versions in order to have a clean set of dependencies.

Automation is always performed in the context of a session. Clients initiate a session with a server in ways specific to each library, but they all end up sending a POST /session request to the server, with a JSON object called the ‘desired capabilities’ object. At this point the server will start up the automation session and respond with a session ID which is used for sending further commands.

The Appium Client

The Appium client is the component that sends commands to the Appium server. The client libraries are available in different programming languages, including Java, Python, Ruby, and others. The client libraries offer a platform-independent interface for mobile automation testing, allowing automation testers to write automation scripts in their preferred language. The Appium client provides a set of APIs that allow testers to automate different types of mobile testing scenarios, such as automating user interactions with the application’s UI elements, testing application flows, and validating the application’s behavior. Understanding the Appium client is essential for automation testers to create effective mobile automation testing strategies.

Appium Desktop

There is a GUI wrapper around the Appium server that can be downloaded for any platform. It comes bundled with everything required to run the Appium server, so you don’t need to worry about Node. It also comes with an Inspector, which enables you to check out the hierarchy of your app. This can come in handy when writing tests.

Appium’s Desired Capabilities

Appium’s Desired Capabilities are a set of key-value pairs that define the testing requirements for the mobile application. These capabilities include the platform name, device name, application path, and other capabilities that are essential for testing the mobile application. The Desired Capabilities define the device and platform on which the tests will be executed, as well as the capabilities required to test the specific application.

Appium supports both iOS and Android, and Desired Capabilities can be set up accordingly to execute tests on the desired platform. Understanding Appium’s Desired Capabilities is essential for automation testers to create effective mobile automation testing strategies. By setting up the desired capabilities correctly, testers can ensure that the mobile application is tested thoroughly across different devices and platforms.

Conclusion

Appium is a popular open-source automation testing tool used for mobile application testing. Understanding its architecture and components can help testers and developers effectively automate mobile testing. The Appium server, client, and desired capabilities are essential components that make Appium one of the most preferred mobile automation testing tools. By understanding these components, automation testers can create robust and effective automation testing strategies for mobile applications.