DeveloperOS DevUtils Suite

An independent, production-grade developer utility suite containing 20 offline, zero-storage utilities built for the DeveloperOS ecosystem.

---

🚀 Live Application: https://devos-devutils.streamlit.app

🌟 Overview & Architecture

DeveloperOS DevUtils provides developers with essential formatting, validation, encoding, inspection, and web design utilities. All operations run strictly in-memory client-side, with zero analytics, zero server telemetry, and zero remote logging.

Architectural Principles

• Decoupled Architecture: All algorithms and business logic are contained in core/ as pure Python modules with zero Streamlit dependencies.
• Plug-and-Play Registry: Tools self-register through tools/registry.py with 13 metadata fields adhering to the DeveloperOS Tool Plugin Contract.
• Security Guardrails:
  • ReDoS protection and string length limits on regex execution.
  • XXE and Billion Laughs defense on XML parsing (safe minidom parser with entity expansion rejection).
  • Explicit warning banner on JWT decoding noting structural-only decode without cryptographic verification.
  • Safe payload caps across all file and input parsers.

---

🛠️ The 20 DevUtils Utilities

#	Tool Name	Category	Module	Description & Capabilities
1	JSON Formatter	Formatters & Converters	core/json_formatter.py	Prettify, indent (2/4 spaces), sort keys, or minify JSON payloads.
2	JSON Validator	Formatters & Converters	core/json_validator.py	Strict RFC 8259 syntax validation with line/column error reporting.
3	JSON ↔ CSV Converter	Formatters & Converters	core/json_csv_converter.py	Bidirectional converter between tabular JSON objects and CSV files.
4	YAML ↔ JSON Converter	Formatters & Converters	core/yaml_json_converter.py	Seamless translation between YAML manifests and JSON payloads.
5	XML Formatter	Formatters & Converters	core/xml_formatter.py	Prettify/minify XML with XXE and entity expansion security defense.
6	Base64 Encoder/Decoder	Security & Encoders	core/base64_codec.py	Standard and URL-safe Base64 encoding/decoding with padding normalization.
7	JWT Decoder	Security & Encoders	core/jwt_decoder.py	Inspect header & payload claims with timestamps; non-cryptographic disclaimer.
8	UUID Generator	Security & Encoders	core/uuid_generator.py	Bulk generate UUIDv4 (random) and UUIDv1 (timestamp) with casing and braces.
9	Regex Tester	Security & Encoders	core/regex_tester.py	Real-time pattern evaluation, match group extraction, and text replacement.
10	Cron Builder	Security & Encoders	core/cron_builder.py	Visual 5-part cron schedule builder and English schedule explainer.
11	Unix Timestamp Converter	Text & Inspection	core/unix_timestamp.py	Epoch seconds/milliseconds to UTC, ISO 8601, local time, and date parsing.
12	URL Encoder/Decoder	Text & Inspection	core/url_codec.py	Percent-encoding, decoding, and URL component/query parameter inspector.
13	Text Diff Checker	Text & Inspection	core/text_diff.py	Side-by-side and unified diff generator with similarity and delta metrics.
14	Hash Calculator	Text & Inspection	core/hash_calculator.py	Multi-algorithm hashing (SHA-256/512/MD5), HMAC, and constant-time verification.
15	Markdown Previewer	Text & Inspection	core/markdown_previewer.py	Live preview, heading outline generator, metrics, and XSS script tag alerts.
16	HTML Minifier	Web & Design Tools	core/html_minifier.py	Strip comments and collapse whitespace while preserving code/pre blocks.
17	CSS Minifier	Web & Design Tools	core/css_minifier.py	Strip comments, collapse selectors/delimiters, and optimize stylesheets.
18	Color Converter	Web & Design Tools	core/color_converter.py	Convert HEX, RGB, HSL, CMYK, and verify WCAG AA accessibility contrast.
19	Text Case Converter	Web & Design Tools	core/text_case_converter.py	camelCase, PascalCase, snake_case, CONSTANT_CASE, kebab-case, and more.
20	QR Code Generator	Web & Design Tools	core/qr_code_generator.py	Generate vector SVG and PNG QR codes with configurable error correction.

---

📁 Repository Structure

suites/developeros-devutils/
├── app.py                      # Main Streamlit application entrypoint
├── manifest.yaml               # Suite metadata & 20-tool catalog
├── requirements.txt            # Runtime dependencies
├── pyproject.toml              # Build & test tooling configuration
├── LICENSE                     # MIT License
├── README.md                   # Suite documentation
├── CONTRIBUTING.md             # Developer contribution guidelines
├── .env.example                # Environment variable template
├── .streamlit/
│   └── config.toml             # DeveloperOS dark theme tokens
├── .github/workflows/
│   └── ci.yml                  # GitHub Actions CI workflow
├── assets/                     # Portable branding assets
│   ├── logo.svg
│   └── theme.json
├── components/                 # Reusable DeveloperOS UI widgets
│   ├── header.py
│   ├── footer.py
│   ├── navigation.py
│   ├── privacy.py
│   ├── alerts.py
│   └── related_tools.py
├── core/                       # Pure Python core logic (20 modules)
│   ├── base64_codec.py
│   ├── color_converter.py
│   ├── cron_builder.py
│   ├── css_minifier.py
│   ├── hash_calculator.py
│   ├── html_minifier.py
│   ├── json_csv_converter.py
│   ├── json_formatter.py
│   ├── json_validator.py
│   ├── jwt_decoder.py
│   ├── markdown_previewer.py
│   ├── qr_code_generator.py
│   ├── regex_tester.py
│   ├── text_case_converter.py
│   ├── text_diff.py
│   ├── unix_timestamp.py
│   ├── url_codec.py
│   ├── uuid_generator.py
│   ├── xml_formatter.py
│   └── yaml_json_converter.py
├── tools/                      # Streamlit UI views for all 20 tools
│   ├── __init__.py             # Auto-registration bootstrap
│   ├── registry.py             # ToolRegistry singleton & contract
│   └── *_view.py               # Individual tool UI views
└── tests/                      # Automated unit & integration tests
    ├── test_batch1_formatters.py
    ├── test_batch2_security_encoders.py
    ├── test_batch3_text_inspection.py
    ├── test_batch4_web_design.py
    ├── test_suite_registration.py
    ├── test_manifest.py
    └── test_registry.py

---

🚀 Running Locally

1. Prerequisites

• Python 3.12+

2. Setup Virtual Environment

python3 -m venv .venv
source .venv/bin/activate
pip install -r requirements.txt

3. Run Streamlit Application

streamlit run app.py

Open your browser at http://localhost:8501.

4. Run Test Suite

python3 -m unittest discover -s tests -p "test_*.py"

---

🔒 Security & Privacy Guarantees

• No Remote Processing: All utilities execute locally in the client runtime.
• Strict Bounds:
  • Payloads capped between 1MB – 5MB depending on tool category.
  • Regex patterns limited to 500 characters and 100,000 text characters to eliminate ReDoS attack vectors.
  • XML parsers explicitly disallow external entity declarations (<!ENTITY ... SYSTEM ...>).
• Cryptographic Disclaimer: The JWT tool is explicitly marked as a structural decoder only and does not verify signature authenticity.

---

🏷️ Recommended GitHub Topics

When configuring this repository on GitHub, apply these topics: devutils developer-tools formatters encoders validators streamlit offline-first developeros open-source

---

📜 License & Attribution

Distributed under the MIT License. See LICENSE for details.

• Live Application: https://devos-devutils.streamlit.app
• Main Website: https://developeros.in
• Central Tools Directory: https://toolkit.developeros.in
• GitHub Organization: https://github.com/developerOSindia