OpenTelemetry (Recommended)
#### Python (Flask)
```python
from opentelemetry import trace
from opentelemetry.exporter.jaeger.thrift import JaegerExporter
from opentelemetry.sdk.resources import SERVICE_NAME, Resource
from opentelemetry.sdk.trace import TracerProvider
from opentelemetry.sdk.trace.export import BatchSpanProcessor
from opentelemetry.instrumentation.flask import FlaskInstrumentor
from flask import Flask
# Initialize tracer
resource = Resource(attributes={SERVICE_NAME: "my-service"})
provider = TracerProvider(resource=resource)
processor = BatchSpanProcessor(JaegerExporter(
agent_host_name="jaeger",
agent_port=6831,
))
provider.add_span_processor(processor)
trace.set_tracer_provider(provider)
# Instrument Flask
app = Flask(__name__)
FlaskInstrumentor().instrument_app(app)
@app.route('/api/users')
def get_users():
tracer = trace.get_tracer(__name__)
with tracer.start_as_current_span("get_users") as span:
span.set_attribute("user.count", 100)
# Business logic
users = fetch_users_from_db()
return {"users": users}
def fetch_users_from_db():
tracer = trace.get_tracer(__name__)
with tracer.start_as_current_span("database_query") as span:
span.set_attribute("db.system", "postgresql")
span.set_attribute("db.statement", "SELECT * FROM users")
# Database query
return query_database()
```
#### Node.js (Express)
```javascript
const { NodeTracerProvider } = require('@opentelemetry/sdk-trace-node');
const { JaegerExporter } = require('@opentelemetry/exporter-jaeger');
const { BatchSpanProcessor } = require('@opentelemetry/sdk-trace-base');
const { registerInstrumentations } = require('@opentelemetry/instrumentation');
const { HttpInstrumentation } = require('@opentelemetry/instrumentation-http');
const { ExpressInstrumentation } = require('@opentelemetry/instrumentation-express');
// Initialize tracer
const provider = new NodeTracerProvider({
resource: { attributes: { 'service.name': 'my-service' } }
});
const exporter = new JaegerExporter({
endpoint: 'http://jaeger:14268/api/traces'
});
provider.addSpanProcessor(new BatchSpanProcessor(exporter));
provider.register();
// Instrument libraries
registerInstrumentations({
instrumentations: [
new HttpInstrumentation(),
new ExpressInstrumentation(),
],
});
const express = require('express');
const app = express();
app.get('/api/users', async (req, res) => {
const tracer = trace.getTracer('my-service');
const span = tracer.startSpan('get_users');
try {
const users = await fetchUsers();
span.setAttributes({ 'user.count': users.length });
res.json({ users });
} finally {
span.end();
}
});
```
#### Go
```go
package main
import (
"context"
"go.opentelemetry.io/otel"
"go.opentelemetry.io/otel/exporters/jaeger"
"go.opentelemetry.io/otel/sdk/resource"
sdktrace "go.opentelemetry.io/otel/sdk/trace"
semconv "go.opentelemetry.io/otel/semconv/v1.4.0"
)
func initTracer() (*sdktrace.TracerProvider, error) {
exporter, err := jaeger.New(jaeger.WithCollectorEndpoint(
jaeger.WithEndpoint("http://jaeger:14268/api/traces"),
))
if err != nil {
return nil, err
}
tp := sdktrace.NewTracerProvider(
sdktrace.WithBatcher(exporter),
sdktrace.WithResource(resource.NewWithAttributes(
semconv.SchemaURL,
semconv.ServiceNameKey.String("my-service"),
)),
)
otel.SetTracerProvider(tp)
return tp, nil
}
func getUsers(ctx context.Context) ([]User, error) {
tracer := otel.Tracer("my-service")
ctx, span := tracer.Start(ctx, "get_users")
defer span.End()
span.SetAttributes(attribute.String("user.filter", "active"))
users, err := fetchUsersFromDB(ctx)
if err != nil {
span.RecordError(err)
return nil, err
}
span.SetAttributes(attribute.Int("user.count", len(users)))
return users, nil
}
```
Reference: See references/instrumentation.md