Bromium

Bromium as a project aims to provide the required infrastructure to automate tasks in Microsoft Windows Desktop Applications. It is devided in two main components:

• the bromium Python library that provides bindings to interact with the Windows UI Automation API through Rust. It enables users to automate tasks and interact with Windows UI elements programmatically.
• the UI Expore Desktop application (inspired by inspect.exe) which allows users to inspect the current Windows Desktop, get xpath locators to any ui element on the desktop and test custom xpah locators. It can be run without a need to install the application and without admin rights. This can be built from source by cloning the github repository https://github.com/dangrazh/bromium/

This is the actual Python library that provides bindings to interact with the Windows UI Automation API.

Key Features of python library

• Get representation of all UI elements on the current desktop (UI tree)
• Launch an application or activate an already running appliation window
• Interact with UI elements on the current desktop
• Get screen context information (size, scaling, etc.)
• Take screen shots
• Get cursor position coordinates
• Retrieve UI element information at specific coordinates

Installation

pip install bromium

Usage

Quickstart

import bromium

# Initialize logging (optional, but helpful for debugging)
bromium.init_logging(log_level="Info", enable_console=True)

# Create a WinDriver — builds the UI Automation tree
driver = bromium.WinDriver(timeout_ms=5000, window_title=None)
print(f"Elements in tree: {len(driver)}")

# Get cursor position and find the element under it
x, y = driver.get_cursor_pos()
element = driver.get_element_by_coordinates(x, y)
print(f"Element at cursor: {element.name} ({element.control_type})")

# Look up an element by XPath (retries until timeout_ms if not found)
found = driver.get_element_by_xpath(element.xpath)
print(f"Found: {found.name}")

# Click the element
found.send_click()

App Launch Example

import bromium
import time

bromium.init_logging(log_level="Info", enable_console=True)

driver = bromium.WinDriver(timeout_ms=5000)
print(f"Driver has {driver.element_count} elements.")

# Launch or activate an application
app_path = r"ms-teams.exe"
xpath = r"/Pane[@Name='Desktop 1']/Window[@Name='Microsoft Teams']"

try:
    app_window = driver.launch_or_activate_app(app_path, xpath)
    print(f"App window: {app_window.name}")
    time.sleep(3)

    # Refresh the tree in place (no need to reassign)
    driver.refresh(window_title="Microsoft Teams")
    print(f"Tree refreshed: {driver.element_count} elements.")

    # Find and click a button
    login_btn = driver.get_element_by_xpath("//Button[@Name='Sign in']", timeout_ms=3000)
    login_btn.send_click()

except bromium.ElementNotFoundError:
    print("Element not found — app may already be logged in.")
except bromium.AutomationError as e:
    print(f"Automation error: {e}")

Iterating & Filtering Elements

import bromium

driver = bromium.WinDriver(timeout_ms=5000)

# Collection protocols
print(f"Total elements: {len(driver)}")
print(f"XPath exists: {'//Button[@Name=\"OK\"]' in driver}")

# Iterate all elements
for elem in driver:
    if elem.control_type == "Button":
        print(f"  Button: {elem.name}")

# Filter with find_elements (case-insensitive substring match)
buttons = driver.find_elements(control_type="Button")
edits = driver.find_elements(control_type="Edit", name="Search")

API Reference

Module-level Functions

These are the recommended entry points for logging configuration:

• init_logging(log_path=None, log_level=None, enable_console=None, enable_file=None) -> None: Initialize the bromium logging system.
• get_version() -> str: Returns the current bromium version string.
• get_log_file() -> str: Returns the current log file path.
• set_log_file(log_file: str) -> None: Sets the full path for the log file. Creates parent directories if needed.
• get_log_level() -> str: Returns the current logging level as a string.
• set_log_level(log_level: str) -> None: Sets the logging level ("Off", "Error", "Warn", "Info", "Debug", "Trace").
• set_log_directory(log_directory: str) -> None: Sets a custom directory for log files. A timestamped file is created automatically.
• enable_console_logging(enable: bool) -> None: Enable or disable console logging.
• enable_file_logging(enable: bool) -> None: Enable or disable file logging.
• reset_log_file() -> None: Clear all contents from the current log file.

Exceptions

• ElementNotFoundError: Raised when a UI element cannot be located (by xpath, coordinates, or runtime ID).
• AutomationError: Raised when a UI Automation operation fails (click, send_keys, etc.).
• TreeConstructionError (extends TimeoutError): Raised when the UI tree cannot be built or refreshed.

WinDriver

The main class for interacting with the Windows UI Automation tree.

Constructor

• WinDriver(timeout_ms: int, window_title: Optional[str] = None): Creates a new driver and builds the UI tree. timeout_ms is the default retry duration for element lookups. window_title optionally filters the tree to a specific window.

Properties

Collection Protocols

• len(driver) — returns element count
• for elem in driver — iterates all elements in the tree
• xpath in driver — checks if an XPath exists in the tree

Methods

• get_cursor_pos() -> tuple[int, int]: Returns the current cursor position as (x, y) coordinates.
• get_element_by_coordinates(x: int, y: int) -> Element: Returns the UI element at the given screen coordinates.
• get_element_by_xpath(xpath: str, timeout_ms: Optional[int] = None) -> Element: Finds an element by XPath. Retries with tree refreshes until timeout_ms elapses. When None, uses the driver's default timeout_ms. Pass 0 to disable retrying.
• get_elements_by_xpath(xpath: str) -> list[Element]: Returns all elements matching an XPath expression.
• find_elements(control_type: Optional[str] = None, name: Optional[str] = None) -> list[Element]: Filters elements by case-insensitive substring match on control type and/or name. Returns an empty list if none match.
• refresh(window_title: Optional[str] = None) -> None: Refreshes the UI tree in place. Uses the stored window_title if no argument is provided.
• launch_or_activate_app(app_path: str, xpath: str) -> Element: Launches or activates an application, returning the element matching the XPath.
• get_screen_context() -> ScreenContext: Returns information about all connected display screens.
• take_screenshot() -> str: Takes a screenshot, saves it to a temp directory, and returns the file path.
• pretty_print_ui_tree() -> None: Prints the UI tree to stdout for debugging.

Element

Represents a Windows UI Automation element.

Properties

Methods

• send_click() -> None: Sends a click (uses Invoke pattern if available, otherwise mouse click at center).
• send_double_click() -> None: Sends a double-click at the element center.
• send_right_click() -> None: Sends a right-click at the element center.
• hold_click(holdkeys: str) -> None: Clicks while holding modifier keys ("ctrl", "shift", "alt").
• send_keys(keys: str) -> None: Sends keyboard input. Special keys use {} syntax (e.g., {ctrl}{alt}{delete}). Groups with () (e.g., {ctrl}(AB) for Ctrl+A+B).
• send_text(text: str) -> None: Sends plain text (uses Value pattern if available, otherwise simulated keystrokes).
• hold_send_keys(holdkeys: str, keys: str, interval: int) -> None: Sends keys while holding modifiers with a custom interval in milliseconds.
• show_context_menu() -> None: Shows the context menu for this element.

ScreenContext

Information about all display screens in the system. Automatically detects all connected displays on construction.

Properties

ScreenInfo

Information about a single display screen.

Properties

LogLevel

Enum for log level values: LogLevel.Error, LogLevel.Warn, LogLevel.Info, LogLevel.Debug, LogLevel.Trace, LogLevel.Off.

Bromium (Legacy)

A static-method-only class that mirrors the module-level functions above. Prefer using bromium.init_logging(...) directly instead of Bromium.init_logging(...).

Requirements

• Python 3.12 or higher
• Windows operating system

Building from Source

To build the project from source, you'll need:

1. Rust toolchain (cargo, rustc)
2. Python 3.12+
3. maturin (for building Python wheels)

# Clone the repository
git clone https://github.com/dangrazh/bromium.git
cd bromium

# Build the project using maturin
maturin build

# Install in development mode
maturin develop

License

Apache License 2.0