OpenTelemetry Java Custom Instrumentation Example

This repository provides an example of using custom instrumentation with OpenTelemetry in a simple Java application. The application consists of two parts: the application code (in /simple-java/src/main/java/org/davidgeorgehope/Main.java) and the custom instrumentation code (in /opentelemetry-custom-instrumentation/src/main/java/org/davidgeorgehope/WordCountInstrumentation.java).

Files

1. WordCountInstrumentation.java - This file contains the code for custom instrumentation. It instruments the method countWords in the Main class and adds custom telemetry to track method execution.

2. Main.java - This file contains the code for the simple Java application. It asks for a sentence from the user and calculates the word count of the sentence.

3. Dockerfile - This is a Dockerfile for packaging the application and the instrumentation into a single Docker image.

Building and Running the Application

1. You can build the application using Docker. The provided Dockerfile builds the simple-java and opentelemetry-custom-instrumentation Maven projects and packages them into a Docker image along with the OpenTelemetry Java agent.

   To build the Docker image, navigate to the root directory of this repository and run:

   docker build -t djhope99/custom-otel-instrumentation:1 .
   

   Replace djhope99/custom-otel-instrumentation:1 with your desired image name.

2. To run the Docker container, use the following command:

   docker run -it -e 'SERVER_URL=XXX' -e 'SECRET_KEY=XXX' djhope99/custom-otel-instrumentation:1
   

   Replace YourEndpointURL and YourSecretKey with your actual endpoint URL and secret key for the OpenTelemetry collector. Replace simple-java-opentelemetry with your image name if you chose a different name during build.

Contributing

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

License

Apache 2.0