Function read_devtools_active_port

src/browser.rs:28–65

Read DevToolsActivePort file and construct the WebSocket URL.

(user_data_dir: &Path)

/// Read DevToolsActivePort file and construct the WebSocket URL.
fn read_devtools_active_port(user_data_dir: &Path) -> Result<String> {
    let port_path = user_data_dir.join("DevToolsActivePort");

    let content = std::fs::read_to_string(&port_path).map_err(|_| {
        anyhow!(
            "Could not read DevToolsActivePort at {}\n\n\
             Make sure Chrome is running with remote debugging enabled:\n\
             1. Open Chrome\n\
             2. Go to chrome://inspect/#remote-debugging\n\
             3. Enable the remote debugging server",
            port_path.display()
        )
    })?;

    let lines: Vec<&str> = content
        .lines()
        .map(|l| l.trim())
        .filter(|l| !l.is_empty())
        .collect();

    if lines.len() < 2 {
        bail!(
            "Invalid DevToolsActivePort content: expected port and path, got: {:?}",
            content.trim()
        );
    }

    let port: u16 = lines[0]
        .parse()
        .map_err(|_| anyhow!("Invalid port '{}' in DevToolsActivePort", lines[0]))?;

    if port == 0 {
        bail!("Port 0 in DevToolsActivePort — Chrome may not be running");
    }

    let path = lines[1];
    Ok(format!("ws://127.0.0.1:{port}{path}"))
}

/// Get the default Chrome user data directory for the given channel.
fn default_chrome_user_data_dir(channel: &str) -> Result<PathBuf> {