HyperDX Java Otel Demo

This is a minimal Java application that demonstrates how to send logs and distributed traces to HyperDX using the OpenTelemetry Java Agent.

The app:

• Starts an embedded HTTP server on localhost:8080
• Exposes several endpoints that simulate workflows, internal processing, and external calls
• Uses the OpenTelemetry Java agent to auto-instrument traces and logs
• Sends all observability data to HyperDX with minimal setup

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✨ Features

• ✅ Auto-instrumented HTTP server with SLF4J (Logback)
• ✅ Rich logs with trace_id and span_id included
• ✅ Simulated internal and external requests (e.g., httpbin.org)
• ✅ A /full-run route that triggers all endpoints in sequence to showcase full trace trees
• ✅ One-command setup via ./build.sh

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🛠 Requirements

• Java 21+
• Maven 3.8+
• HyperDX account and API key
• Internet access to download the OpenTelemetry Java agent

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🚀 Quick Start

1. Clone the Repository

git clone https://github.com/hyperdxio/sample-java-app.git
cd hyperdx-java-demo

2. Set Your API Key

export API_KEY="your-hyperdx-api-key"

3. Run the Project (build, download agent, launch)

./build.sh

☝️ This script:

• Compiles the app with Maven
• Downloads the OpenTelemetry Java agent
• Sets the required environment variables
• Runs the app with instrumentation enabled

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🔍 Endpoints

Route	Description
/hello	Basic response with traceable log
/user?id=123	Simulates a DB-like operation
/order?id=999	Simulates an external HTTP call
/workflow	Calls /user and /order internally
/full-run	Calls all the above to simulate a full trace

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📈 What You'll See in HyperDX

• Each route generates a trace with logs and spans
• /full-run builds a full nested trace tree like this:

/full-run
├── /hello
├── /user?id=123
├── /order?id=999
│   └── https://httpbin.org/delay/1
└── /workflow
    ├── /user?id=123
    └── /order?id=999
        └── https://httpbin.org/delay/1

• Logs attached to each span contain trace_id and span_id

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🧩 Customization Ideas

• Add error handling or latency simulation
• Add custom span attributes (e.g. user.id)
• Build a second service to simulate cross-service traces
• Add metrics using OTEL SDK

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📄 License

MIT – feel free to use, fork, modify, and contribute.