MW Injector 🚀

Zero-configuration Java application instrumentation that actually works.

MW Injector automatically discovers, instruments, and manages Java applications across your entire infrastructure with a single command.

⚡ Quick Start

# List all Java processes
sudo mw-injector list-all

# Auto-instrument everything (host processes)
sudo mw-injector auto-instrument

# Auto-instrument Docker containers
sudo mw-injector instrument-docker

# List instrumented containers
sudo mw-injector list-docker

Config-based mode (no prompts, uses saved config)

sudo mw-injector auto-instrument-config

Auto-instrument Docker containers

sudo mw-injector instrument-docker-config

🔧 Configuration File

Create a config file to avoid repetitive API key prompts and enable fully automated instrumentation:

# Create system-wide config
sudo tee /etc/mw-injector.conf << EOF
MW_API_KEY=your_middleware_api_key_here
MW_TARGET=https://prod.middleware.io:443
MW_JAVA_AGENT_PATH=/opt/middleware/agents/middleware-javaagent-1.8.1.jar
EOF

That's it. Your Java apps are now sending telemetry data to Middleware.io.

🎯 What Makes This Different

• Auto-Discovery: Finds Java processes everywhere - host, Docker, Docker Compose, systemd services
• Zero Configuration: No manual agent setup, no classpath hell, no environment variable gymnastics
• Intelligent Detection: Recognizes Tomcat instances, Spring Boot apps, JAR files, and service types
• Permission-Aware: Handles user contexts, systemd security, and file access automatically
• Reversible: Clean uninstrumentation that restores original state
• Production-Ready: Designed for enterprise environments with proper error handling

🔥 Core Capabilities

Process Discovery

Found 3 Java processes:

PID: 1234
  Service: user-auth-service
  Owner: appuser
  Agent: ❌ None
  Type: Spring Boot
  Config: ❌ Not configured

PID: 5678
  Service: tomcat-ecommerce
  Owner: tomcat
  Agent: ✅ MW
  Type: Tomcat
  Instance: ecommerce
  Webapps: [api, admin, shop]
  Config: ✅ /etc/middleware/tomcat/tomcat-ecommerce.conf

Docker Integration

Found 2 Java Docker containers:

Container: payment-service
  Image: openjdk:11-jre-slim
  Agent: ❌ Not instrumented
  Type: Docker Compose
  Project: microservices
  Service: payment

Container: legacy-app
  Image: tomcat:9.0
  Agent: ✅ Instrumented
  JAR Files: [legacy-app.war]

Tomcat Support

• Automatically detects Tomcat instances and webapps
• Supports multiple Tomcat deployments per host
• Handles CATALINA_OPTS integration
• Per-webapp service naming with context expansion

Systemd Integration

• Creates proper systemd drop-in files
• Manages service restarts automatically
• Handles permission contexts and security policies
• Supports both standard Java services and Tomcat

🛠 Installation

# Build the project (Yeah yeah release pipeline will be coming soon) 
go build -o mw-injector ./cmd/mw-injector

# Make executable
chmod +x mw-injector

# Move to PATH
sudo mv mw-injector /usr/local/bin/

📋 Requirements

• Linux (systemd-based distributions)
• Root privileges (for system-wide instrumentation)
• Docker (optional, for container instrumentation)
• Middleware.io account and API key

🎮 Usage Examples

Basic Workflow

# 1. See what's running
sudo mw-injector list-all

# 2. Auto-instrument everything
sudo mw-injector auto-instrument
# Enter your Middleware.io API key when prompted

# 3. Verify instrumentation, it would show the instrumented services
sudo mw-injector list-all

# 4. Check your Middleware.io dashboard
# 🎉 Data should be flowing

Docker Containers

# Instrument all Java containers
sudo mw-injector instrument-docker

# Instrument specific container
sudo mw-injector instrument-container my-java-app

# Remove instrumentation
sudo mw-injector uninstrument-docker

Cleanup

# Remove all systemd instrumentation
sudo mw-injector uninstrument

# Remove Docker instrumentation
sudo mw-injector uninstrument-docker

🏗 Architecture

MW Injector is built with a modular architecture:

• Agent Management: Handles Java agent installation and permissions
• Process Discovery: Finds and analyzes Java processes across the system
• Service Naming: Generates intelligent service names from process context
• Systemd Integration: Manages service configuration and restarts
• State Management: Tracks instrumentation state and handles cleanup

Built with ❤️ and way too much nicotine on sleepless nights

Making Java instrumentation suck less, one process at a time.