How to add a progress bar to an Elixir CLI tool?

Use ProgressBar.render/2 or /3 with the current and total values, and call it repeatedly for updates. For example, ProgressBar.render(50, 100) shows a 50% bar. Customize with options like width or suffix for bytes.

ProgressBar vs simple_bar for Elixir?

ProgressBar offers more features like spinners, indeterminate bars, and ANSI color customization, while simple_bar is likely simpler. However, ProgressBar is not actively maintained, so for new projects, consider forking or using alternatives with ongoing support.

How to customize spinner frames in ProgressBar?

Specify the frames option as a list of strings or use predefined atoms like :braille. For instance, ProgressBar.render_spinner([frames: ["O", "o"]], fn -> end) creates a custom spinner. Details are in the 'Predefined spinners' section.

ProgressBar not showing in Docker or CI environments?

This library relies on terminal interactivity and ANSI escape codes. Ensure STDOUT is a TTY; in non-interactive environments like Docker logs, it may fail. The automatic width detection might also default to 80 columns if unsupported.

How to handle download progress with ProgressBar?

Use the suffix: :bytes option to display byte counts with automatic unit conversion. For example, ProgressBar.render(bytes_received, total_bytes, suffix: :bytes) shows MB or KB, as demonstrated in the 'suffix: :bytes' section.

Can ProgressBar be used for high-frequency updates?

While you can set low intervals (e.g., 10ms), frequent redraws with ANSI styling might cause performance overhead or flicker. It's best suited for moderate update rates, such as progress on batch processing or downloads.

progress_bar — Elixir CLI Progress Bar Library

What is progress_bar?

ProgressBar is an Elixir library that provides customizable progress bars and spinners for command-line interfaces. It helps developers visualize task progress, downloads, or indeterminate operations directly in the terminal, enhancing user experience for CLI tools.

Target Audience

Elixir developers building command-line tools or scripts that require visual feedback for long-running tasks, such as data processing, file downloads, or batch operations.

Value Proposition

Developers choose ProgressBar for its straightforward API and extensive customization options, including configurable colors, formats, and animations, allowing it to fit diverse CLI use cases without unnecessary complexity.

Command-line progress bars and spinners for Elixir.

Use Cases

Best For

Adding determinate progress bars to CLI tools that process a known number of items or bytes.
Implementing indeterminate progress indicators for tasks with unknown duration, like network requests or complex computations.
Displaying animated spinners with custom text for loading states in terminal applications.
Visualizing download progress with automatic byte unit formatting (e.g., MB, KB).
Creating custom-styled progress indicators with specific colors, characters, and ANSI styling for branded CLI tools.
Enhancing user experience in Elixir scripts by providing real-time feedback on task execution.

Not Ideal For

Projects requiring actively maintained dependencies with long-term support and security updates.
Applications needing progress visualization in non-interactive or redirected output streams (e.g., logs, files).
Systems where minimal external dependencies are critical, as it adds a library for terminal-specific functionality.

Pros & Cons

Pros

Simple and Intuitive API

Functions like ProgressBar.render/2 allow easy integration with minimal code, as demonstrated in the basic usage examples where passing current and total values renders a bar.

Extensive Customization Options

Supports custom formats, colors using IO.ANSI, and adjustable widths, enabling tailored progress indicators for any CLI aesthetic, as detailed in the 'Customize format' and 'Customize color' sections.

Automatic Terminal Adaptation

The bar automatically fits its width to the terminal size, with a fallback to 80 columns if undetectable, ensuring compatibility across different environments without manual configuration.

Multiple Indicator Types

Offers determinate bars, indeterminate bars, and spinners with predefined styles like :braille, catering to various progress visualization needs, as shown in the examples for each type.

Cons

Inactive Maintenance Status

The README explicitly states the project is 'Not actively maintained' as of 2025-07-22, posing risks for bug fixes, compatibility updates, and long-term viability in production environments.

Limited Output Flexibility

Designed primarily for STDOUT overwriting with carriage returns, making it unsuitable for environments where output is redirected or non-interactive, as it relies on terminal-specific behavior.

Basic Animation Control

While intervals are configurable, the animation logic for spinners and indeterminate bars is simplistic, with fixed frame sequences that may not support advanced effects or dynamic adjustments beyond user-defined lists.

What is progress_bar?

Target Audience

Elixir developers building command-line tools or scripts that require visual feedback for long-running tasks, such as data processing, file downloads, or batch operations.

Value Proposition

Use Cases

Best For

Adding determinate progress bars to CLI tools that process a known number of items or bytes.
Implementing indeterminate progress indicators for tasks with unknown duration, like network requests or complex computations.
Displaying animated spinners with custom text for loading states in terminal applications.
Visualizing download progress with automatic byte unit formatting (e.g., MB, KB).
Creating custom-styled progress indicators with specific colors, characters, and ANSI styling for branded CLI tools.
Enhancing user experience in Elixir scripts by providing real-time feedback on task execution.

Not Ideal For

Projects requiring actively maintained dependencies with long-term support and security updates.
Applications needing progress visualization in non-interactive or redirected output streams (e.g., logs, files).
Systems where minimal external dependencies are critical, as it adds a library for terminal-specific functionality.

Pros & Cons

Pros

Simple and Intuitive API

Functions like ProgressBar.render/2 allow easy integration with minimal code, as demonstrated in the basic usage examples where passing current and total values renders a bar.

Extensive Customization Options

Automatic Terminal Adaptation

The bar automatically fits its width to the terminal size, with a fallback to 80 columns if undetectable, ensuring compatibility across different environments without manual configuration.

Multiple Indicator Types

Offers determinate bars, indeterminate bars, and spinners with predefined styles like :braille, catering to various progress visualization needs, as shown in the examples for each type.

Cons

Inactive Maintenance Status

The README explicitly states the project is 'Not actively maintained' as of 2025-07-22, posing risks for bug fixes, compatibility updates, and long-term viability in production environments.

Limited Output Flexibility

Designed primarily for STDOUT overwriting with carriage returns, making it unsuitable for environments where output is redirected or non-interactive, as it relies on terminal-specific behavior.

Basic Animation Control

progress_bar

What is progress_bar?

Overview

Use Cases

Best For

Not Ideal For

Pros & Cons

Pros

Cons

Frequently Asked Questions

Related Projects

Found a gem we're missing?

progress_bar

What is progress_bar?

Overview

Use Cases

Best For

Not Ideal For

Pros & Cons

Pros

Cons

Frequently Asked Questions

Related Projects

Found a gem we're missing?