service-ping (sping)

Modern terminal HTTP/TCP latency monitoring tool with real-time visualization. Think httping meets modern CLI design with rich terminal UI, phase timing, and advanced analytics.

Status: Feature-complete MVP with HTTP/TCP support, phase timing, outlier detection, and comprehensive monitoring capabilities.

Demo

Real-time latency monitoring with interactive charts showing HTTP response times, outlier detection, and live statistics.

Why?

I've frequently found myself using nvitop to diagnose GPU/CPU contention issues.

The two best things about it are:

• It's easy to install if I can access pip in the container
• It makes a compelling screenshot (which helps me communicate with coworkers.)

With those two lessons in mind: Here is Sping!

Purpose: Help observe and diagnose latency issues at layer 4+ (TCP/HTTP/HTTPS)

Two good things about it:

• It's easy to install if you have pip. (Available at service-ping-sping on PyPi)
• It makes a compelling screenshot.

Features

• 🌐 HTTP & TCP Monitoring: Support for http://, https://, and tcp:// protocols
• 📊 Real-time Visualization: Interactive charts and live statistics in your terminal
• 🔍 Phase Breakdown: DNS, connection, TLS, request, and response timing
• 🚨 Outlier Detection: Automatic outlier detection using MAD (Median Absolute Deviation)
• ⚠️ Threshold Alerting: Warning and critical thresholds with exit codes
• 🌍 DNS Control: IPv4/IPv6 selection and DNS resolution caching
• 📈 Advanced Statistics: Percentiles (p50, p90, p95, p99), standard deviation
• 💾 Multiple Output Formats: Interactive UI, plain text, JSON, and JSON export
• 🔐 Authentication: Bearer tokens and basic auth support
• 🎨 Rich Terminal UI: Beautiful charts, color-coded logs, and responsive layouts
• 🌈 Color Palettes: Choose from 8 themed color schemes (sunset, ocean, forest, volcano, galaxy, arctic, neon, monochrome)

Install

pip install service-ping-sping

For development:

pip install -e .[dev]

Quick Start

# HTTP monitoring with interactive UI
sping google.com

# TCP connection monitoring
sping tcp://google.com:80

# HTTPS with custom options
sping https://api.example.com --interval 0.5 --count 20

# JSON output for automation
sping google.com --json --count 5

# Advanced monitoring with thresholds
sping example.com --warn 100 --crit 500 --percentiles

# Try different color themes
sping example.com --palette ocean

Usage Examples

HTTP/HTTPS Monitoring

# Basic HTTP monitoring (auto-adds http://)
sping example.com

# HTTPS with custom method and body transfer
sping https://api.example.com --method POST --body

# IPv4 only with DNS caching
sping google.com --ipv4 --resolve-once

# With authentication
sping api.example.com --auth "bearer:your-token"
sping api.example.com --auth "user:password"

TCP Connection Monitoring

# Test TCP connectivity
sping tcp://google.com:80
sping tcp://example.com:443

# Monitor database connections
sping tcp://localhost:5432 --interval 0.1

Advanced Features

# Outlier detection and thresholds
sping example.com --warn 100 --crit 500 --count 100

# Export detailed timing data
sping example.com --export-file results.json --count 50

# Show percentile statistics
sping example.com --percentiles --count 100

# Plain output for scripting
sping example.com --plain --count 5

Outlier Detection

sping automatically detects unusual latency spikes using Median Absolute Deviation (MAD) analysis:

What Counts as an Outlier

• Latency outliers: Response times that deviate significantly from recent baseline performance
• Statistical threshold: Latencies that are more than 6x the MAD away from the median
• Baseline requirement: Needs at least 10 successful samples to establish baseline
• Rolling window: Uses the last 30 successful requests to calculate normal behavior
• Successful requests only: Only analyzes successful responses (errors are tracked separately)

How It Works

1. Baseline calculation: Median of recent 30 successful latencies (e.g., 100ms)
2. Variability measure: MAD of those latencies (e.g., 15ms)
3. Outlier threshold: |current_latency - median| / MAD > 6.0
4. Example: If baseline is 100ms ± 15ms MAD, requests > 190ms or < 10ms would be outliers

Visual Indicators

• Interactive mode: Outlier requests show [OUTLIER] marker in the log
• Statistics bar: Shows red outlier count when detected (e.g., outliers 3)
• JSON output: "anomaly": true field in export data (kept for API compatibility)

Note: Outlier detection helps identify performance degradation, network issues, or service problems that might not trigger error thresholds.

Command Line Options

Core Options

• -i, --interval FLOAT: Seconds between probes (default: 1.0)
• -c, --count INT: Number of probes then exit
• --timeout FLOAT: Request timeout in seconds (default: 10.0)
• -X, --method TEXT: HTTP method (default: HEAD)

Protocol & DNS

• --ipv4: Force IPv4 only
• --ipv6: Force IPv6 only
• --resolve-once: Resolve DNS only once and cache

HTTP Options

• --body: Include full body transfer time
• --no-keepalive: Disable persistent connections
• --user-agent TEXT: Custom User-Agent string
• --auth TEXT: Authentication (user:pass or bearer:token)
• --insecure: Skip TLS verification

Monitoring & Alerts

• --warn FLOAT: Warning threshold in milliseconds
• --crit FLOAT: Critical threshold in milliseconds
• --percentiles: Show percentile statistics in summary

UI & Display

• --refresh-rate FLOAT: UI update throttling in Hz (default: 4.0, higher = more responsive, lower = less CPU)
• --palette PALETTE: Color palette for latency visualization (default: sunset)
• --xterm-colors-only: Force basic terminal color compatibility (useful for older terminals)

Color Palettes

Choose from beautiful themed color palettes to customize your latency visualization:

Sunset Palette (Default)

Warm oranges and reds reminiscent of a beautiful sunset

#626262 #808080 #6B59C3 #836FFF #8968CD #AB82FF #CD96CD #FFBBFF #CD8C95 #FFAEB9

# Examples with different palettes
sping example.com --palette ocean
sping example.com --palette volcano --count 20
sping example.com --palette neon --percentiles

Color Compatibility Notes

Terminal Color Support: sping automatically detects your terminal's color capabilities and adjusts accordingly. However, older terminals or certain environments may experience:

• Limited Color Support: Older terminals may only support basic ANSI colors rather than rich RGB colors
• Solution: Set TERM=xterm-256color in your environment or use --xterm-colors-only for consistent basic colors
• Compatibility Mode: Use --xterm-colors-only to force basic terminal colors that work everywhere

# For maximum compatibility with older terminals
sping example.com --xterm-colors-only

# Or set environment variable for better color support
TERM=xterm-256color sping example.com

Output Formats

• --json: JSON output mode (one object per line)
• --plain: Plain text output mode
• --export-file FILE: Export JSON results to file

Output Formats

Interactive Mode (Default)

Real-time terminal UI with:

• Live latency chart with gradient coloring
• Recent requests log with timing details
• Statistics panel with min/mean/max/stdev
• Outlier highlighting and threshold indicators

Plain Text Mode (--plain)

[1] 1755658486.287: 484.313ms 200 (application/json) from httpbin.org (52.1.207.236)
--- https://httpbin.org/get sping summary ---
1 probes, 1 ok, 0 errors
Latency (ms): min 484.313 mean 484.313 max 484.313

JSON Mode (--json)

{"seq": 1, "timestamp": 1755658729.193, "latency_ms": 11.110, "status_code": 0, "error": null, "bytes_read": 0, "content_type": "tcp/connection", "host_address": "google.com (142.250.65.238)", "anomaly": false, "phases": {"dns_ms": 5.444, "connect_ms": 5.598, "tls_ms": null, "request_write_ms": null, "ttfb_ms": null, "body_read_ms": null, "total_ms": 11.110}}

Phase Timing Breakdown

sping provides detailed timing for each phase of the connection:

• DNS: Domain name resolution time
• Connect: TCP connection establishment
• TLS: TLS/SSL handshake time (HTTPS only)
• Request Write: Time to send HTTP request
• TTFB: Time to first byte (response headers)
• Body Read: Time to read response body
• Total: End-to-end request time

Exit Codes

• 0: Success
• 1: Warning threshold exceeded (when --warn specified)
• 2: Critical threshold exceeded (when --crit specified)

Perfect for monitoring scripts and alerting systems.

Quit Interactive Mode

Press Ctrl+C to gracefully exit and see the final summary.

Requirements

• Python 3.9+
• Modern terminal with color support recommended
• Works on Linux, macOS, and Windows

License

MIT - see LICENSE.md