Integrate Opentelemetry with Flask

Watch tracing into console with ConsoleSpanExporter

.gitignore

@@ -8,3 +8,6 @@ venv/
 
 # production environment config
 .env
+
+# vscode
+.vscode/

app.py

@@ -7,13 +7,36 @@
 from flask_restful import Resource, Api
 from dotenv import load_dotenv
 
+from opentelemetry import trace
+from opentelemetry.instrumentation.flask import FlaskInstrumentor
+from opentelemetry.instrumentation.requests import RequestsInstrumentor
+from opentelemetry.sdk.trace import TracerProvider
+from opentelemetry.sdk.trace.export import (
+    ConsoleSpanExporter,
+    SimpleSpanProcessor,
+)
+
 load_dotenv()  # take environment variables from .env
 
+# set trace provider as default one
+trace.set_tracer_provider(TracerProvider())
+trace.get_tracer_provider().add_span_processor(
+    SimpleSpanProcessor(ConsoleSpanExporter())
+)
+
 app = Flask(__name__)
 api = Api(app)
 
+FlaskInstrumentor().instrument_app(app)
+RequestsInstrumentor().instrument()
+
+
 class HelloWorld(Resource):
     def get(self):
+        tracer = trace.get_tracer(__name__)
+        with tracer.start_as_current_span("example-request"):
+            requests.get("http://www.example.com")
+            print("Hello World")
         return {'hello': 'world'}
 
 api.add_resource(HelloWorld, '/')