https://github.com/rstudio/webdriver

WebDriver client in R
https://github.com/rstudio/webdriver

Last synced: 3 days ago
JSON representation

WebDriver client in R

• Host: GitHub
• URL: https://github.com/rstudio/webdriver
• Owner: rstudio
• License: other
• Created: 2016-08-18T11:20:46.000Z (about 8 years ago)
• Default Branch: main
• Last Pushed: 2022-06-10T20:44:17.000Z (over 2 years ago)
• Last Synced: 2024-06-11T18:14:49.658Z (5 months ago)
• Language: R
• Homepage: https://rstudio.github.io/webdriver/
• Size: 1.82 MB
• Stars: 68
• Watchers: 10
• Forks: 17
• Open Issues: 27
• Metadata Files:
  • Readme: README.Rmd
  • License: LICENSE

Awesome Lists containing this project

• jimsghstars - rstudio/webdriver - WebDriver client in R (R)

README

        
---

output: github_document

---

```{r, setup, echo = FALSE, message = FALSE}

knitr::opts_chunk$set(

  tidy = FALSE,

  fig.width = 4,

  fig.height = 12,

  fig.path = "man/figures")

```

```{r screenshot-manual, eval = FALSE, include = FALSE}

# Run this code to update the images (since results are random)

pjs <- webdriver::run_phantomjs()

ses <- Session$new(port = pjs$port)

ses$go("https://r-pkg.org/pkg/callr")

ses$takeScreenshot(file="man/figures/screenshot-1.png")

search <- ses$findElement("#cran-input")

search$sendKeys("html", key$enter)

ses$takeScreenshot(file="man/figures/screenshot-2.png")

```

# webdriver

> 'WebDriver' Client for 'PhantomJS'

[![R-CMD-check](https://github.com/rstudio/webdriver/actions/workflows/R-CMD-check.yaml/badge.svg)](https://github.com/rstudio/webdriver/actions)

[![](https://www.r-pkg.org/badges/version/webdriver)](https://www.r-pkg.org/pkg/webdriver)

[![CRAN RStudio mirror downloads](https://cranlogs.r-pkg.org/badges/webdriver)](https://www.r-pkg.org/pkg/webdriver)

[![Coverage Status](https://img.shields.io/codecov/c/github/rstudio/webdriver/main.svg)](https://codecov.io/github/rstudio/webdriver?branch=main)

A client for the 'WebDriver' 'API'. It allows driving a (probably headless)

web browser, and can be used to test web applications, including 'Shiny'

apps. In theory it works with any 'WebDriver' implementation, but it was only

tested with 'PhantomJS'.

## Installation

```r

install.packages("webdriver")

```

## Usage

```{r}

library(webdriver)

```

### PhantomJS

webdriver uses PhantomJS as a headless web browser. (In theory in works

with other WebDriver clients as well.) You can use the `install_phantomjs()`

function to download and install PhantomJS on your system. Alternatively

an installation that is in the PATH is sufficient.

The `run_phantomjs()` function starts PhantomJS, and waits until it is ready

to serve queries. It returns a process object that you can terminate

manually, and the port on which PhantomJS is listening.

```{r, results='hide'}

pjs <- run_phantomjs()

pjs

```

    ## $process

    ## PROCESS 'phantomjs', running, pid 17405.

    ##

    ## $port

    ## [1] 6795

### Sessions

Use the `Session` class to connection to a running PhantomJS process.

One process can save multiple sessions, and the sessions are independent

of each other.

```{r}

ses <- Session$new(port = pjs$port)

```

Once a session is established, you can manipulate the headless web browser

through it:

```{r}

ses$go("https://r-pkg.org/pkg/callr")

ses$getUrl()

ses$getTitle()

```

You can also take a screenshot of the whole web page, and show it on R's

graphics device, or save it to a PNG file:

```{r screenshot-1, eval = FALSE}

ses$takeScreenshot()

```

![](man/figures/screenshot-1.png)

### HTML elements

The `Session` object has two methods to find HTML elements on the current

web page, which can then be further manipulated: `findElement()` and

`findElements()`. They work with CSS or XPATH selectors, and also with

(possibly partial) HTML text.

```{r}

install <- ses$findElement(".install-package")

install$getName()

install$getText()

```

If you have an HTML element that can receive keyboard keys, you can use

the `sendKeys()` method to send them. The `key` list helps with sending

special, characters, e.g. `key$enter` corresponds to pressing ENTER. For

example we can type into a search box:

```{r}

search <- ses$findElement("#cran-input")

search$sendKeys("html", key$enter)

ses$getUrl()

ses$getTitle()

```

```{r screenshot-2, eval = FALSE}

ses$takeScreenshot()

```

![](man/figures/screenshot-2.png)

### JavaScript

The `executeScript()` method of a `Session` object runs arbitrary JavaScript

in the headless browser. It puts the supplied code into the body of a

JavaScript function, and the function will receive the additional arguments,

in its `arguments` array. `Element` objects as arguments are automatically

converted to the corresponding DOM elements in the browser.

The JavaScript function can return values to R. Returned HTML elements are

automatically converted to `Element` objects.

```{r}

ses$executeScript("return 42 + 'foobar';")

```

```{r}

search2 <- ses$executeScript("return document.getElementById('cran-input');")

search2$getName()

```

`Element` objects also have an `executeScript()` method, which works the

same way as the `Session` method, but it automatically supplies the HTML

element as the first argument of the JavaScript function.

`executeScript()` works synchronously. If you need asynchronous execution,

you can use the `executeScriptAsync()` function.

## License

MIT © Mango Solutions, RStudio