Last updated: Jul 26, 2018 10:08
By Guy Heimann
Progressive Web Apps (PWA) are creating waves in the mobile application community. Allowing a web application to act like a mobile application allows the user to know that his application is in-sync with the service provider's web-site services. Apple's Safari browser has introduced, in iOS 11.3, support for configuring any website, whose creator defined the ability to configure the site as a PWA, to install the corresponding PWA on the home page of your iOS device.
Perfecto Lab provides the tools to launch, test, and close the PWA on the iOS device. Whether you use Appium or Perfecto's Native Automation you can test the PWA as if it were a hybrid application without performing any instrumentation.
This article does not address how to create the PWA, but, rather with how one works on iOS and how you can automate it using the Perfecto Lab.
Safari Support for Installing PWA
When using the Safari browser, it’s possible to generate a special shortcut to the current open page, using the share tool that Safari supplies in the status line of the display (see below):
To install the PWA:
- Browse to the website that is defined, by the website creator, to be PWA-ready:
- Click on the share icon (red circle, above).
- In the share options popup, click on the Add to Home Screen button.
- You can accept the default name (based on the website title) or supply a new name. Click Add.
- The PWA is "installed" on the home-page of the device, linked to the URL of the website, and ready to be activated.
How it works
If the web developer configured the site to allow it to work as a PWA, once the PWA is launched from the shortcut- the URL will be open without the Safari native part. If the site is not configured to work as PWA, Safari will be launched with the URL (same as regular work with Safari web pages).
When PWA is launched, it behaves like an independent app. Safari isn’t involved in the process and it looks to the user just like a new native iOS application, without the Safari wrapper - meaning no URL text-box at top and no status line at bottom:
In actuality, when “installing” the PWA, no new application is being added to the device. When clicking on the PWA icon, Apple’s Webapp is launched without Safari. This Webapp (com.apple.webapp) is a container that runs a web view, different PWAs will run in different Webapp instances.
Automating the PWA from Appium
As we outlined, the PWA is not coupled to Safari but, on the other hand, it is not a unique application. Therefore, to test it, user must:
- Use the Appium IOSDriver
- Explicitly launch the PWA from inside the script using the Start PWA command (see below).
Meaning that the application cannot be launched from the Desired Capabilities, like a native application, but should be considered a mobile hybrid application that runs in an iOS environment (without Safari).
Launching the application
Use the Perfecto Extension Command mobile:pwa:start to launch the PWA with the displayName as a parameter.
The display name is the label of the PWA icon on the home page:
Closing the application
Use Perfecto Extension Command mobile:pwa:stop to close the PWA (no parameters needed):
Switch Context to Identify UI Elements
The Perfecto Lab considers the PWA as if it were a hybrid application, meaning:
The website user interface elements are all DOM elements, and should be accessed (via XPath) using the WEBVIEW context.
The application wrapper elements (for example, application header), and the XCUIElementTypeWebViewthat encapsulates the website are all native application elements, and should be accessed (via XPath) using the NATIVE_APP context.
Automating the PWA from Native Automation
Using the Perfecto Lab IDE to automate the PWA, is possible using the new Applications functions:
- Use the Start PWA (under “Applications”) function to activate the PWA and provide the display name of the PWA icon as a parameter.
- Use the Stop PWA (under “Applications”) function to stop the PWA execution, no parameters needed.
Note: Stop PWA function will only close the PWA if it is running in the foreground, otherwise it will throw an error.
The Object Spy will identify the UI Elements of the PWA and provide accurate placement of the elements to support using the Native Automation functions and commands to automate the application functionality.
The following limitations exist in the current version of the Perfecto support for PWA automation:
- Only applicable for devices running iOS 11.3 or later.
- Not supported for iPad devices in Landscape Mode.
- No instrumentation supported for PWA - this limits the use of the Sensor Instrumentation related functionality of Camera Image Injection, Fingerprint authentication, etc.