## 🚀 Feature Proposal

Add support for the WebAuthn Automation API, a standard WebDriver extension that allows developers to create virtual authenticators to test websites using WebAuthn.

https://w3c.github.io/webauthn/#sctn-automation

_note: the above link may not work until https://github.com/w3c/webauthn/pull/1340 is merged_

## Motivation

At the moment there is no practical way to write e2e tests for pages using WebAuthn. Since this is a standard WebDriver API, the cost of implementing a layer on java is low.

## Example

For a page like this

```html
<button id="signup">Sign up with webauthn</button>
<span id="result"></span>
```

```javascript
document.getElmentById("signup").addEventListener("click", () => {
  navigator.credentials.create({...}).then(credentials => {
    document.getElementById("result").innerText = "Success!";
  })
});
```

A test could be written like so:

```java
// HasVirtualAuthenticator is an interface that augments a RemoteWebDriver.
HasVirtualAuthenticator virtualAuthenticatorManager = ((HasVirtualAuthenticator) driver);
VirtualAuthenticatorOptions options = new VirtualAuthenticatorOptions();
VirtualAuthenticator authenticator =
    virtualAuthenticatorManager.addVirtualAuthenticator(options);
driver.findElement(By.id("signup")).click();
WebElement result = driver.findElement(By.id("result"));
new WebDriverWait(driver, 60, 1000).until(
    driver -> !result.getText().equals(""));
assertThat(result.getText()).isEqualTo("Success!");
```

## Implementation

We can implement the AddVirtualAuthenticator and RemoveVirtualAuthenticator methods first since they're the most useful and follow up with the others in subsequent PRs.
* @param method The request method.
     * @param parts The parsed request path segments.
     * @return Whether this instance matches the request.
     */
    boolean isFor(HttpMethod method, ImmutableList<String> parts) {
      if (!this.method.equals(method)) {
        return false;
      }
      if (parts.size() != this.pathSegments.size()) {
        return false;
      }
      for (int i = 0; i < parts.size(); ++i) {
        String reqPart = parts.get(i);
        String specPart = pathSegments.get(i);
        if (!(specPart.startsWith(":") || specPart.equals(reqPart))) {
          return false;
        }
      }
      return true;
    }
    void parsePathParameters(ImmutableList<String> parts, Map<String, Object> parameters) {
      for (int i = 0; i < parts.size(); ++i) {
        if (pathSegments.get(i).startsWith(":")) {
          parameters.put(pathSegments.get(i).substring(1), parts.get(i));
        }
      }
    }
  }
}