Jeamlit's native app testing framework

Jeamlit provides Playwright end-to-end test utilities to make it simple for developers to build and run automated tests.

Import the test dependencies:

maven (pom.xml):

<dependency>
    <groupId>io.jeamlit</groupId>
    <artifactId>jeamlit</artifactId>
    <version>0.19.0</version>
    <type>test-jar</type>
    <scope>test</scope>
</dependency>

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Warning

The testing utilities depend on JUnit. Please reach out on Github to get help with other testing frameworks.

Test your app

import io.jeamlit.e2e.helpers.PlaywrightUtils;
import static io.jeamlit.e2e.helpers.PlaywrightUtils.WAIT_1_SEC_MAX;

import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.TestInfo;

import static com.microsoft.playwright.assertions.PlaywrightAssertions.assertThat;

@Test
public void testMyApp(TestInfo testInfo) {
    PlaywrightUtils.runInSharedBrowser(testInfo, app, page -> {
        // interact with the app and perform assertions
        // example: ensure a dateInput component appears properly
        assertThat(page.locator("jt-date-input").first()).isVisible(WAIT_1_SEC_MAX);
    });
}

Explanations :

TestInfo is injected by JUnit.
app is the Jeamlit app as a String, a Path or a Class. See full documentation below.
page is a com.microsoft.playwright.Page. For more information, visit the Playwright For Java documentation
PlaywrightUtils.runInSharedBrowser takes care of starting a Jeamlit server, launching a headless browser on an available port and navigating to the app page.
WAIT_1_SEC_MAX means the timeout for the check is 1 second. The default timeout in Playwright is often 30 seconds. A lot of option constants with lower timeout values are provided, just type WAIT_ in your IDE when filling options of a Playwright method, it should suggest all relevant constants from io.jeamlit.e2e.helpers.PlaywrightUtils.

The Jeamlit server runs with the test classpath.
Test traces are written in the target/playwright-traces/ folder.

Available methods

// run in a shared browser (recommended, faster) 
// The tests run on different pages in the browser, but the browser is shared so cookies, storage, etc... are shared
// Thread safe. Each call launches a Jeamlit server.  
PlaywrightUtils.runInSharedBrowser(String testName, Path appFile, Consumer<Page> run);
PlaywrightUtils.runInSharedBrowser(String testName, String app, Consumer<Page> run);

// run in a dedicated browser
// use when you need to test behaviors that depend on the browser cookies, storage, cache 
PlaywrightUtils.runInDedicatedBrowser(String testName, Path appFile, Consumer<Page> run);
PlaywrightUtils.runInDedicatedBrowser(String testName, String app, Consumer<Page> run);
PlaywrightUtils.runInDedicatedBrowser(String testName, Class<?> appClass, Consumer<Page> run);

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