add metrics

Author: ks6088ts

docs/index.md

@@ -25,3 +25,7 @@
 - [FastAPI のテレメトリデータを Azure Application Insights に送る](https://qiita.com/hoto17296/items/2f366dfabdbe3d1d4e97)
 - [【Azure Functions】 - Application Insights のログが表示されない問題](https://zenn.dev/headwaters/articles/ff19f7e1b99b44)
 - [opentelemetry-instrumentation-fastapi (python) から OpenTelemetry に入門する](https://zenn.dev/taxin/articles/opentelemetry-fast-api-instrumentation-basics)
+
+## OpenTelemetry
+
+- [Docs > Language APIs & SDKs > Python > Getting Started](https://opentelemetry.io/docs/languages/python/getting-started/)

template_fastapi/app.py

@@ -9,20 +9,14 @@
 
 from azure.monitor.opentelemetry import configure_azure_monitor
 from fastapi import FastAPI, HTTPException, Query
-from opentelemetry import trace
 from opentelemetry.instrumentation.fastapi import FastAPIInstrumentor
-from opentelemetry.sdk.trace import TracerProvider
-from opentelemetry.sdk.trace.export import (
-    BatchSpanProcessor,
-    ConsoleSpanExporter,
-)
 from opentelemetry.trace import Span
 from pydantic import BaseModel
 
-trace.set_tracer_provider(TracerProvider())
-trace.get_tracer_provider().add_span_processor(BatchSpanProcessor(ConsoleSpanExporter()))
-tracer = trace.get_tracer(__name__)
+from template_fastapi.opentelemetry import get_meter, get_tracer
 
+tracer = get_tracer(__name__)
+meter = get_meter(__name__)
 app = FastAPI()
 
 # If APPLICATIONINSIGHTS_CONNECTION_STRING exists, configure Azure Monitor
@@ -189,6 +183,7 @@ async def flaky(failure_rate: int):
 
 
 # Add flaky API which raises an exception
+@tracer.start_as_current_span("flaky_exception")
 @app.get("/flaky/exception", tags=["flaky"], operation_id="flaky_exception")
 async def flaky_exception():
     """
@@ -216,9 +211,29 @@ async def heavy_sync_with_sleep(sleep_ms: int):
 
     import time
 
-    with tracer.start_as_current_span("foo"):
+    with tracer.start_as_current_span("parent"):
         print(f"Sleeping for {sleep_ms} milliseconds")
         time.sleep(sleep_ms / 1000.0)
+        with tracer.start_as_current_span("child"):
+            print("Child span")
     return {
         "message": f"Slept for {sleep_ms} milliseconds",
     }
+
+
+# Add counter for dice rolls
+roll_counter = meter.create_counter(
+    "dice.rolls",
+    description="The number of rolls by roll value",
+)
+
+
+@app.get("/roll_dice", operation_id="roll_dice")
+async def roll_dice():
+    """
+    Simulate rolling a dice and record the roll in the meter.
+    """
+    with tracer.start_as_current_span("roll_dice"):
+        roll = random.randint(1, 6)
+        roll_counter.add(1, {"roll.value": str(roll)})
+    return roll

template_fastapi/opentelemetry.py

@@ -0,0 +1,16 @@
+from opentelemetry import metrics, trace
+from opentelemetry.sdk.trace import TracerProvider
+from opentelemetry.sdk.trace.export import (
+    BatchSpanProcessor,
+    ConsoleSpanExporter,
+)
+
+
+def get_tracer(name: str):
+    trace.set_tracer_provider(TracerProvider())
+    trace.get_tracer_provider().add_span_processor(BatchSpanProcessor(ConsoleSpanExporter()))
+    return trace.get_tracer(name)
+
+
+def get_meter(name: str):
+    return metrics.get_meter(name)