How to control Chromedriver using curl

Here is how to use Chromedriver without libraries like selenium-webdriver. This can be useful for debugging.

The following example visits a web page and reads the a headline's text contents.

1. Create a session:

   Copycurl -XPOST http://localhost:9515/session -d '{"desiredCapabilities":{"browserName":"chrome"}}'
   

   You will get a JSON response containing lots of information about your Chrome session, including a sessionId. Use this to send any future commands to your chromedriver session.

   Copy{"sessionId":"your-session-id-here","status":0,"value":{...}}
   

   You might want to pass options as into the chromeOptions capabilities e.g. --headless: '{"desiredCapabilities":{"browserName":"chrome", "chromeOptions":{"args":["--headless"]}}}'

2. Visit a URL like this:

   Copycurl http://localhost:9515/session/your-session-id-here/url -d '{"url":"http://example.com/"}'
   

   Copy{"sessionId":"...","status":0,"value":null}
   

3. Finding elements is fairly simple:

   Copycurl http://localhost:9515/session/your-session-id-here/element -d '{"using":"tagName","value":"h1"}'
   

   Copy{"sessionId":"...","status":0,"value":{"ELEMENT":"element-object-id-here"}}
   

4. Read the element's text content by using the element's identifier received above:

   Copycurl http://localhost:9515/session/your-session-id-here/element/element-object-id-here/text
   

   Copy{"sessionId":"...","status":0,"value":"Example Domain"}
   

5. To close Chrome, terminate your session:

   Copycurl -XDELETE http://localhost:9515/session/your-session-id-here
   

   Copy{"sessionId":"...","status":0,"value":null}
   

Chromedriver follows the W3C WebDriver spec. There are tons of things you can do with it, but performing more advanced tasks without a tool like selenium-webdriver can be quite difficult.
However, for simple debugging or remote-controlling, curl might be an adequate option.