The sample shop service will be used in this guide.

Follow the steps given below to view Ballerina metrics, traces and logs in OpenSearch.

Step 1 - Set up OpenSearch

This section focuses on configuring OpenSearch with Docker as a quick installation.

1. Download and unzip the opensearch-observability-dashboard.zip in your local machine.

   The opensearch-observability-dashboard directory structure should look like this:

   ├── config
   │   ├── dashboards
   │   │   └── opensearch_dashboards.yml
   │   ├── data-prepper
   │   │   └── pipelines.yaml
   │   ├── fluent-bit
   │   │   ├── fluent-bit.conf
   │   │   ├── parsers.conf
   │   │   └── scripts
   │   │       └── scripts.lua
   │   └── .env
   ├── logs
   │   └── ballerina
   ├── setup
   │   ├── opensearch-dashboards-template.ndjson
   │   └── index-template-request.json
   └── docker-compose.yml
   

2. Update OPENSEARCH_INITIAL_ADMIN_PASSWORD in the path/to/opensearch-observability-dashboard/config/.env file.

   OPENSEARCH_INITIAL_ADMIN_PASSWORD=<PASSWORD> # Password for the OpenSearch admin user

   This password will be used to access the OpenSearch server.

3. Navigate to the path/to/opensearch-observability-dashboard directory and run docker compose to start the OpenSearch server.

   docker compose -f docker-compose.yml up -d
   

Step 2 - Set up Ballerina application for observability

1. Open the main.bal file in the Ballerina package and add the following imports.

   import ballerinax/metrics.logs as _;
   import ballerinax/jaeger as _;

2. Create the Config.toml file in the package directory to set the runtime configurations as follows.

   [ballerina.observe]
   metricsLogsEnabled = true
   tracingEnabled = true
   tracingProvider = "jaeger"
    
   [ballerinax.jaeger]
   agentHostname = "localhost"
   agentPort = 4317
   samplerType = "const"
   samplerParam = 1.0
   reporterFlushInterval = 2000
   reporterBufferSize = 1000
    
   [ballerinax.metrics.logs]
   logFilePath = "<PATH>/<TO>/opensearch-observability-dashboard/logs/ballerina/<NAME_FOR_SERVICE>/app.log"

   Update the logFilePath with the path to openSearch observability dashboard logs directory, which is path/to/opensearch-observability-dashboard/logs/ballerina/<NAME_FOR_SERVICE>/app.log.

   These configurations enable metrics, logs, and traces in the Ballerina application and configure the Jaeger exporter.

   The table below provides the descriptions of each configuration option and possible values that can be assigned.

   Configuration key	Description	Default value	Possible values
   ballerinax.jaeger. agentHostname	Hostname of the Jaeger agent	localhost	IP or hostname of the Jaeger agent. Can be localhost if running on same node as Ballerina.
   ballerinax.jaeger. agentPort	Port of the Jaeger agent	4317	The port on which the Jaeger agent is listening.
   ballerinax.jaeger. samplerType	Type of sampling methods used in Jaeger tracer	const	const, probabilistic, or ratelimiting
   ballerinax.jaeger. samplerParam	Floating value parameter for sampler	1.0	const: 0 (no sampling) or 1 (sample all) probabilistic: 0.0 to 1.0 ratelimiting: positive integer (rate/sec)
   ballerinax.jaeger. reporterFlushInterval	Interval for sending spans to agent	2000	Any positive integer value
   ballerinax.jaeger. reporterBufferSize	Queue size of Jaeger client	1000	Any positive integer value
   ballerinax.metrics.logs. logFilePath	Path to application log file	none	PATH/TO/opensearch-observability-dashboard/logs/ballerina/<SERVICE_NAME>/app.log

Step 3 - Run the Ballerina service

When Ballerina observability is enabled, the Ballerina runtime collects metrics, logs, and traces.

Run the following command to start the Ballerina service.

$ bal run

Compiling source

Running executable

ballerina: started publishing traces to Jaeger on localhost:4317

Step 4 - Send requests

Send requests to http://localhost:8090/shop.

Example cURL commands:

$ curl -X GET http://localhost:8090/shop/products

$ curl -X POST http://localhost:8090/shop/product \
-H "Content-Type: application/json" \
-d '{
    "id": 4, 
    "name": "Laptop Charger", 
    "price": 50.00
}'

$ curl -X POST http://localhost:8090/shop/order \
-H "Content-Type: application/json" \
-d '{
    "productId": 1, 
    "quantity": 1
}'

$ curl -X GET http://localhost:8090/shop/order/0

Step 5 - View distributed tracing on OpenSearch dashboard

Open the OpenSearch Dashboard in your browser at http://localhost:5601 and log in using the admin credentials you set up in the .env file. Use the username admin and the password you set for OPENSEARCH_INITIAL_ADMIN_PASSWORD.

Navigate to the Traces tab under Observability section.

The image below is a sample tracing information you can see in OpenSearch.

The service map shows the relationship between different services in the system.

Step 6 - View metrics on OpenSearch dashboard

Open the OpenSearch Dashboard in your browser at http://localhost:5601 and navigate to the "Dashboards" tab under "OpenSearch Dashboards" section.

Then click on the "Integration metrics dashboard" to view the metrics.

Step 7 - View logs on OpenSearch dashboard

Open the OpenSearch Dashboard in your browser at http://localhost:5601 and navigate to the "Dashboards" tab under "OpenSearch Dashboards" section.

Then click on the "Integration logs dashboard" to view the integration logs.