> ## Documentation Index
> Fetch the complete documentation index at: https://docs.shardcloud.app/llms.txt
> Use this file to discover all available pages before exploring further.

# How to Host Selenium Applications

> Learn how to run Selenium browser automation scripts on Shard Cloud.

## Introduction

Selenium is a powerful tool for automating web browsers. This guide covers deploying Selenium scripts on Shard Cloud using Python.

## Creating Your Project

Ensure you have **Python** and **pip** installed.

### Installing Dependencies

```bash theme={null}
pip install selenium
```

### Basic Selenium Script

Create a `main.py` file:

```python main.py theme={null}
import time
from selenium import webdriver
from selenium.webdriver.chrome.service import Service
from selenium.webdriver.chrome.options import Options

# Chrome options for headless operation
options = Options()
options.add_argument("--headless")
options.add_argument("--no-sandbox")
options.add_argument("--disable-dev-shm-usage")
options.add_argument("--disable-gpu")

# Initialize the driver
service = Service('/usr/bin/chromedriver')
driver = webdriver.Chrome(service=service, options=options)

# Set window size
driver.set_window_size(1920, 1080)

try:
    # Navigate to a page
    driver.get('https://www.google.com')
    print(f"Page title: {driver.title}")

    # Take a screenshot
    driver.save_screenshot('screenshot.png')
    print("Screenshot saved!")

    # Keep running and take screenshots periodically
    while True:
        driver.save_screenshot('page.png')
        print("Screenshot updated")
        time.sleep(60)

except Exception as e:
    print(f"Error: {e}")
finally:
    driver.quit()
```

### Requirements File

Create a `requirements.txt`:

```txt requirements.txt theme={null}
selenium
```

<Warning>
  The Chrome options `--no-sandbox` and `--disable-dev-shm-usage` are required
  for Selenium to work in containerized environments.
</Warning>

## Chrome/Chromium Path

On Shard Cloud, Chromium is installed at `/usr/bin/chromium` and ChromeDriver at `/usr/bin/chromedriver`. The WebDriver can locate these automatically.

## Shard Cloud Configuration

Create a `.shardcloud` file:

```systemd .shardcloud theme={null}
DISPLAY_NAME=Selenium Bot
DESCRIPTION=Browser Automation Script
MAIN=main.py
MEMORY=1024
VERSION=recommended
```

<Note>
  Selenium applications typically require at least 512MB-1024MB of memory due to
  the browser overhead.
</Note>

## Advanced Example: Web Scraping

```python scraper.py theme={null}
import time
from selenium import webdriver
from selenium.webdriver.chrome.service import Service
from selenium.webdriver.chrome.options import Options
from selenium.webdriver.common.by import By
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC

def setup_driver():
    options = Options()
    options.add_argument("--headless")
    options.add_argument("--no-sandbox")
    options.add_argument("--disable-dev-shm-usage")
    options.add_argument("--disable-gpu")
    options.add_argument("--window-size=1920,1080")

    service = Service('/usr/bin/chromedriver')
    return webdriver.Chrome(service=service, options=options)

def scrape_page(url):
    driver = setup_driver()

    try:
        driver.get(url)

        # Wait for an element to load
        wait = WebDriverWait(driver, 10)
        element = wait.until(
            EC.presence_of_element_located((By.TAG_NAME, "body"))
        )

        # Get page content
        title = driver.title
        content = driver.page_source

        print(f"Title: {title}")
        print(f"Content length: {len(content)} characters")

        return content

    except Exception as e:
        print(f"Error: {e}")
        return None
    finally:
        driver.quit()

if __name__ == "__main__":
    url = "https://example.com"
    result = scrape_page(url)
```

## Deploying

<Steps>
  <Step title="Prepare Your Files">
    Ensure you have: - `main.py` (or your script) - `requirements.txt` -
    `.shardcloud`
  </Step>

  <Step title="Exclude Unnecessary Files">
    Remove: `__pycache__/`, `venv/`, `*.pyc`
  </Step>

  <Step title="Create ZIP Archive">Compress your project folder.</Step>

  <Step title="Upload to Shard Cloud">
    Go to [Shard Cloud Dashboard](https://shardcloud.app/dash/applications) and
    upload.
  </Step>
</Steps>

## Accessing Screenshots

Screenshots saved by your script can be downloaded from Shard Cloud's file manager in the dashboard.

## Additional Resources

* [Selenium Documentation](https://www.selenium.dev/documentation/)
* [Selenium Python Bindings](https://selenium-python.readthedocs.io/)

## Troubleshooting

<AccordionGroup>
  <Accordion title="Chrome crashed">
    * Ensure you're using headless mode - Add `--disable-dev-shm-usage` flag -
      Increase memory allocation
  </Accordion>

  <Accordion title="Element not found">
    * Use WebDriverWait for dynamic content - Verify the selector is correct -
      Take a screenshot to debug the page state
  </Accordion>

  <Accordion title="Out of memory">
    Close the driver after each task and increase the `MEMORY` value in your
    config.
  </Accordion>
</AccordionGroup>