feat: add OpenTelemetry with OTLP exporter

docker-compose.yaml

@@ -0,0 +1,19 @@
+services:
+  docling-serve:
+    build:
+      context: .
+      dockerfile: Containerfile
+    ports:
+      - 5001:5001
+    environment:
+      - DOCLING_SERVE_ENABLE_UI=1
+      - OTEL_EXPORTER_OTLP_ENDPOINT=http://otel:4317
+      - OTEL_SERVICE_NAME=docling-serve
+      - OTEL_ENVIRONMENT=development
+
+  otel:
+    image: grafana/otel-lgtm:latest
+    ports:
+      - 3000:3000 # Web UI
+      - 4317:4317 # OTLP gRPC
+      - 4318:4318 # OTLP HTTP

docling_serve/app.py

@@ -28,6 +28,12 @@
 )
 from fastapi.responses import JSONResponse, RedirectResponse
 from fastapi.staticfiles import StaticFiles
+from opentelemetry import trace
+from opentelemetry.sdk.resources import Resource, SERVICE_NAME
+from opentelemetry.sdk.trace import TracerProvider
+from opentelemetry.sdk.trace.export import BatchSpanProcessor
+from opentelemetry.exporter.otlp.proto.grpc.trace_exporter import OTLPSpanExporter
+from opentelemetry.instrumentation.fastapi import FastAPIInstrumentor
 from scalar_fastapi import get_scalar_api_reference
 
 from docling.datamodel.base_models import DocumentStream
@@ -167,6 +173,13 @@ def create_app():  # noqa: C901
         version=version,
     )
 
+    resource = Resource(attributes={SERVICE_NAME: "docling-serve"})
+    traceProvider = TracerProvider(resource=resource)
+    traceProvider.add_span_processor(BatchSpanProcessor(OTLPSpanExporter()))
+
+    trace.set_tracer_provider(traceProvider)
+    FastAPIInstrumentor.instrument_app(app)
+
     origins = docling_serve_settings.cors_origins
     methods = docling_serve_settings.cors_methods
     headers = docling_serve_settings.cors_headers

pyproject.toml

@@ -46,6 +46,10 @@ dependencies = [
     "websockets~=14.0",
     "scalar-fastapi>=1.0.3",
     "docling-mcp>=1.0.0",
+    "opentelemetry-instrumentation-fastapi>=0.57b0,<0.58",
+    "opentelemetry-api (>=1.36.0,<2.0.0)",
+    "opentelemetry-sdk (>=1.36.0,<2.0.0)",
+    "opentelemetry-exporter-otlp>=1.15.0",
 ]
 
 [project.optional-dependencies]