使用HtmlUnit下载JavaScript图像 [英] Downloading javascript image with HtmlUnit

问题描述

如何使用HtmlUnit下载在 Leaflet easyPrint 按钮生成的图像?

How do I go about downloading the image generated at Leaflet easyPrint button using HtmlUnit?

我正在这样尝试:

public static void main(String[] args) {
        try{
            WebClient webClient = new WebClient();
            HtmlPage test = webClient.getPage("http://rowanwins.github.io/leaflet-easyPrint/");
            webClient.waitForBackgroundJavaScript(5000);

            final DomElement button = test.getFirstByXPath("/html/body/button");
            final InputStream image = button.click().getWebResponse().getContentAsStream();
            System.out.println(image);

            File file = new File("/home/josue/Basis/STS4/map.png");
            copyInputStreamToFile(image, file);
        }
        catch (Exception e) {
            e.printStackTrace();
        }
    }

private static void copyInputStreamToFile(InputStream inputStream, File file) 
        throws IOException {

        try (FileOutputStream outputStream = new FileOutputStream(file)) {

            int read;
            byte[] bytes = new byte[1024];

            while ((read = inputStream.read(bytes)) != -1) {
                outputStream.write(bytes, 0, read);
            }
        }
    }

并获得一个大约3Kb的空白PNG文件. 使它正常工作的正确方法是什么?

And getting a blank PNG file with about 3Kb. What is the proper way to get it working?

编辑:我要完成此操作的原因是，它是Google Maps静态API的一种简单替代方案，目前我已在运行中的项目中对其进行了部署.

EDIT: The reason I want to accomplish it, is to get a simple alternative for Google Maps static API, which I currently have deployed in a running project.

推荐答案

在其他人对此功能感兴趣的情况下，我无法使其与HtmlUnit一起使用，但使用Selenium可获得了预期的结果:

I couldn't get it to work with HtmlUnit, but got the expected result using Selenium, in case someone else is interested in this feature:

public class PG1 {


    static WebDriver driver;

    public static void main(String[] args) throws InterruptedException {
        System.setProperty("webdriver.gecko.driver","/Users/home/Downloads/geckodriver");
        FirefoxOptions fxProfile = new FirefoxOptions();
        fxProfile.setHeadless(true);
        fxProfile.addPreference("browser.download.folderList",2);
        fxProfile.addPreference("browser.download.manager.showWhenStarting",false);
        fxProfile.addPreference("browser.download.dir","/Users/home/Downloads/");
        fxProfile.addPreference("browser.helperApps.neverAsk.saveToDisk","image/png");
        driver = new FirefoxDriver(fxProfile);
        String baseUrl = "http://rowanwins.github.io/leaflet-easyPrint/";
        driver.get(baseUrl);
        while(checkForPresenceOfElementByXpath("")) {
        }
        System.out.println("Loaded");
        driver.findElement(By.xpath("/html/body/button")).click();
        while(checkForPresenceOfElementByXpath("")) {
        }
        System.out.println("Downloaded");
        driver.close();
    }

    public static boolean checkForPresenceOfElementByXpath(String xpath){
        try{
            new WebDriverWait(driver, 5).until(ExpectedConditions.visibilityOfElementLocated(By.xpath("(xpath)[last()]")));
            return true;
        }catch(Exception e){
            return false;
        }
    }
}

这篇关于使用HtmlUnit下载JavaScript图像的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！