juffi 0.4.2

A feature rich TUI JSON log file viewer

Juffi - JSON Log Viewer

A feature-rich Terminal User Interface (TUI) for viewing and analyzing JSON log files with ease.

Why Juffi?

JSON logs are powerful but painful to read in their raw format. Compare these two views of the same log data:

Without Juffi

{"timestamp":"2024-01-15T10:23:45.123Z","level":"INFO","message":"User login successful","user_id":"user_12345","ip":"192.168.1.100","session_id":"abc-def-ghi","service":"auth-service"}
{"timestamp":"2024-01-15T10:23:46.456Z","level":"WARN","message":"High memory usage detected","memory_percent":85.3,"process":"api-server","service":"monitoring"}
{"timestamp":"2024-01-15T10:23:47.789Z","level":"ERROR","message":"Database connection timeout","db_host":"db-primary.example.com","retry_count":3,"error":"connection timeout after 30s","service":"database"}
{"timestamp":"2024-01-15T10:23:48.012Z","level":"INFO","message":"API request received","method":"POST","path":"/api/v1/users","response_time_ms":45,"status_code":200,"service":"api-gateway"}
{"timestamp":"2024-01-15T10:23:49.234Z","level":"DEBUG","message":"Cache hit","cache_key":"user:12345:profile","ttl_seconds":3600,"service":"cache-service"}
{"timestamp":"2024-01-15T10:23:50.567Z","level":"INFO","message":"Payment processed","amount":99.99,"currency":"USD","transaction_id":"txn_abc123","user_id":"user_12345","service":"payment-service"}
{"timestamp":"2024-01-15T10:23:51.890Z","level":"WARN","message":"Rate limit approaching","current_requests":950,"limit":1000,"window_seconds":60,"ip":"192.168.1.100","service":"rate-limiter"}
{"timestamp":"2024-01-15T10:23:52.123Z","level":"ERROR","message":"Failed to send email","recipient":"[e-mail]","error":"SMTP connection refused","retry_attempt":2,"service":"email-service"}
{"timestamp":"2024-01-15T10:23:53.456Z","level":"INFO","message":"File uploaded successfully","filename":"document.pdf","size_bytes":1048576,"user_id":"user_67890","service":"storage-service"}
{"timestamp":"2024-01-15T10:23:54.789Z","level":"DEBUG","message":"SQL query executed","query":"SELECT * FROM users WHERE id = ?","duration_ms":12,"rows_affected":1,"service":"database"}
{"timestamp":"2024-01-15T10:23:55.012Z","level":"INFO","message":"User logout","user_id":"user_12345","session_duration_seconds":1800,"service":"auth-service"}
{"timestamp":"2024-01-15T10:23:56.345Z","level":"WARN","message":"Slow query detected","query":"SELECT * FROM orders JOIN users","duration_ms":5000,"threshold_ms":1000,"service":"database"}
{"timestamp":"2024-01-15T10:23:57.678Z","level":"ERROR","message":"Authentication failed","user_id":"user_99999","reason":"invalid_credentials","ip":"10.0.0.50","service":"auth-service"}
{"timestamp":"2024-01-15T10:23:58.901Z","level":"INFO","message":"Background job completed","job_id":"job_456","job_type":"data_export","duration_seconds":120,"service":"worker"}
{"timestamp":"2024-01-15T10:23:59.234Z","level":"DEBUG","message":"WebSocket connection established","client_id":"ws_client_789","protocol":"wss","service":"websocket-server"}
{"timestamp":"2024-01-15T10:24:00.567Z","level":"INFO","message":"Metrics published","metric_count":150,"destination":"prometheus","service":"metrics-collector"}
{"timestamp":"2024-01-15T10:24:01.890Z","level":"WARN","message":"Disk space low","available_gb":5.2,"total_gb":100,"threshold_percent":10,"mount_point":"/data","service":"monitoring"}
{"timestamp":"2024-01-15T10:24:02.123Z","level":"ERROR","message":"External API timeout","api":"payment-gateway","endpoint":"/charge","timeout_seconds":30,"service":"integration"}
{"timestamp":"2024-01-15T10:24:03.456Z","level":"INFO","message":"Cache cleared","cache_type":"redis","keys_deleted":1500,"service":"cache-service"}
{"timestamp":"2024-01-15T10:24:04.789Z","level":"DEBUG","message":"Request validation passed","endpoint":"/api/v1/orders","validation_time_ms":5,"service":"api-gateway"}
{"timestamp":"2024-01-15T10:24:05.012Z","level":"INFO","message":"Scheduled task started","task_name":"daily_backup","schedule":"0 2 * * *","service":"scheduler"}
{"timestamp":"2024-01-15T10:24:06.345Z","level":"WARN","message":"Connection pool exhausted","pool_size":50,"active_connections":50,"waiting_requests":10,"service":"database"}
{"timestamp":"2024-01-15T10:24:07.678Z","level":"ERROR","message":"Message queue full","queue_name":"notifications","current_size":10000,"max_size":10000,"service":"message-queue"}
{"timestamp":"2024-01-15T10:24:08.901Z","level":"INFO","message":"Health check passed","endpoint":"/health","response_time_ms":2,"status":"healthy","service":"api-gateway"}
{"timestamp":"2024-01-15T10:24:09.234Z","level":"DEBUG","message":"Token refreshed","user_id":"user_12345","token_type":"JWT","expires_in_seconds":3600,"service":"auth-service"}

With Juffi

Features

🔍 Smart Log Viewing

• Automatic column detection - Juffi analyzes your JSON logs and creates columns for all fields
• Tabular display - View logs in a clean, organized table format
• Details view - Dive deep into individual log entries with full JSON expansion

📊 Powerful Filtering & Search

• Column filtering - Filter by any column to focus on relevant entries
• Global search - Search across all fields simultaneously
• Clear filters - Easily reset filters to start fresh

🎯 Column Management

• Sortable columns - Sort by any column (ascending or descending)
• Reorderable columns - Arrange columns in the order that makes sense to you
• Adjustable widths - Resize columns to fit your data
• Column management screen - Hide/show columns as needed

📡 Real-time Monitoring

• Follow mode - Like tail -f, automatically show new log entries as they're written
• Live reload - Refresh the view to pick up new entries
• Responsive updates - Smooth scrolling and navigation even with large files

Installation

From PyPI (Recommended)

pip install juffi

From Source

git clone https://github.com/YotamAlon/juffi.git
cd juffi
pip install -e .

Quick Start

Basic Usage

juffi app.log

Requirements

• Python 3.11 or higher
• Terminal with curses support (most Unix-like systems)
• No external dependencies required

Use Cases

Juffi is perfect for:

• Debugging - Quickly find errors and warnings in application logs
• Monitoring - Watch logs in real-time with follow mode
• Analysis - Sort and filter logs to identify patterns
• Development - Review structured logging output during development
• Operations - Investigate production issues with powerful search and filtering

Technical Details

Architecture

Juffi follows a clean MVVM (Model-View-ViewModel) architecture:

• Models (juffi/models/) - Data structures and business logic
• ViewModels (juffi/viewmodels/) - Presentation logic and state management
• Views (juffi/views/) - UI rendering using Python's curses library
• Input Controller (juffi/input_controller.py) - Handles file reading and input streaming

Project Structure

juffi/
├── juffi/
│   ├── __main__.py           # Entry point
│   ├── input_controller.py   # File input handling
│   ├── models/               # Data models
│   ├── viewmodels/           # Presentation logic
│   ├── views/                # UI components
│   └── helpers/              # Utility functions
├── tests/                    # Test suite
├── pyproject.toml           # Project configuration
└── README.md

Building from Source

Prerequisites

# Install development dependencies
pip install -e ".[dev]"

Build

# Build wheel and source distribution
make build

# Or building a wheel
make wheel

Testing

# Run tests
make test

# Run tests with coverage
make coverage

# Run linter
make lint

Development Setup

1. Clone the repository

   git clone https://github.com/YotamAlon/juffi.git
   cd juffi
   

2. Create virtual environment

   python -m venv .venv
   source .venv/bin/activate
   

3. Install in development mode

   pip install -e ".[dev]"
   

4. Install pre-commit hooks

   pre-commit install
   

Code Quality

The project uses:

• Black - Code formatting
• isort - Import sorting
• mypy - Type checking
• pylint - Linting
• pytest - Testing

All checks run automatically via pre-commit hooks.

License

This project is licensed under the GNU General Public License v3.0 - see the LICENSE file for details.

Author

Yotam Alon - [e-mail]

Links

• Homepage: https://github.com/YotamAlon/juffi
• Issues: https://github.com/YotamAlon/juffi/issues
• PyPI: https://pypi.org/project/juffi/