Menginstrumentasi kode Python di AWS Lambda

Inisialisasi aplikasi menggunakan template Hello World Python.

sam init --app-template hello-world-powertools-python --name sam-app --package-type Zip --runtime python3.9 --no-tracing

Bangun aplikasi.

cd sam-app && sam build

Terapkan aplikasi.

sam deploy --guided

Ikuti petunjuk di layar. Untuk menerima opsi default yang disediakan dalam pengalaman interaktif, tekanEnter.

Dapatkan URL aplikasi yang digunakan:

aws cloudformation describe-stacks --stack-name sam-app --query 'Stacks[0].Outputs[?OutputKey==`HelloWorldApi`].OutputValue' --output text

Memanggil titik akhir API:

curl -X GET <URL_FROM_PREVIOUS_STEP>

Jika berhasil, Anda akan melihat tanggapan ini:

{"message":"hello world"}

Untuk mendapatkan jejak untuk fungsi tersebut, jalankan jejak sam.

sam traces

Output jejak terlihat seperti ini:

New XRay Service Graph
  Start time: 2023-02-03 14:59:50+00:00
  End time: 2023-02-03 14:59:50+00:00
  Reference Id: 0 - (Root) AWS::Lambda - sam-app-HelloWorldFunction-YBg8yfYtOc9j - Edges: [1]
   Summary_statistics:
     - total requests: 1
     - ok count(2XX): 1
     - error count(4XX): 0
     - fault count(5XX): 0
     - total response time: 0.924
  Reference Id: 1 - AWS::Lambda::Function - sam-app-HelloWorldFunction-YBg8yfYtOc9j - Edges: []
   Summary_statistics:
     - total requests: 1
     - ok count(2XX): 1
     - error count(4XX): 0
     - fault count(5XX): 0
     - total response time: 0.016
  Reference Id: 2 - client - sam-app-HelloWorldFunction-YBg8yfYtOc9j - Edges: [0]
   Summary_statistics:
     - total requests: 0
     - ok count(2XX): 0
     - error count(4XX): 0
     - fault count(5XX): 0
     - total response time: 0

XRay Event [revision 1] at (2023-02-03T14:59:50.204000) with id (1-63dd2166-434a12c22e1307ff2114f299) and duration (0.924s)
 - 0.924s - sam-app-HelloWorldFunction-YBg8yfYtOc9j [HTTP: 200]
 - 0.016s - sam-app-HelloWorldFunction-YBg8yfYtOc9j
   - 0.739s - Initialization
   - 0.016s - Invocation
     - 0.013s - ## lambda_handler
       - 0.000s - ## app.hello
   - 0.000s - Overhead

Ini adalah titik akhir API publik yang dapat diakses melalui internet. Kami menyarankan Anda menghapus titik akhir setelah pengujian.

sam delete

Buat direktori proyek untuk aplikasi baru Anda.

mkdir hello-world
cd hello-world

Inisialisasi aplikasi.

cdk init app --language python

Instal dependensi Python.

pip install -r requirements.txt

Buat direktori lambda_function di bawah folder root.

mkdir lambda_function
cd lambda_function

Buat file app.py dan tambahkan kode berikut ke file. Ini adalah kode untuk fungsi Lambda.

from aws_lambda_powertools.event_handler import APIGatewayRestResolver
from aws_lambda_powertools.utilities.typing import LambdaContext
from aws_lambda_powertools.logging import correlation_paths
from aws_lambda_powertools import Logger
from aws_lambda_powertools import Tracer
from aws_lambda_powertools import Metrics
from aws_lambda_powertools.metrics import MetricUnit

app = APIGatewayRestResolver()
tracer = Tracer()
logger = Logger()
metrics = Metrics(namespace="PowertoolsSample")

@app.get("/hello")
@tracer.capture_method
def hello():
    # adding custom metrics
    # See: https://docs.powertools.aws.dev/lambda-python/latest/core/metrics/
    metrics.add_metric(name="HelloWorldInvocations", unit=MetricUnit.Count, value=1)

    # structured log
    # See: https://docs.powertools.aws.dev/lambda-python/latest/core/logger/
    logger.info("Hello world API - HTTP 200")
    return {"message": "hello world"}

# Enrich logging with contextual information from Lambda
@logger.inject_lambda_context(correlation_id_path=correlation_paths.API_GATEWAY_REST)
# Adding tracer
# See: https://docs.powertools.aws.dev/lambda-python/latest/core/tracer/
@tracer.capture_lambda_handler
# ensures metrics are flushed upon request completion/failure and capturing ColdStart metric
@metrics.log_metrics(capture_cold_start_metric=True)
def lambda_handler(event: dict, context: LambdaContext) -> dict:
    return app.resolve(event, context)

Buka direktori hello_world. Anda akan melihat file bernama hello_world_stack.py.

cd ..
cd hello_world

Buka hello_world_stack.py dan tambahkan kode berikut ke file. Ini berisi Konstruktor Lambda, yang membuat fungsi Lambda, mengonfigurasi variabel lingkungan untuk Powertools dan menetapkan retensi log ke satu minggu, dan Konstruktor ApiGatewayv 1, yang membuat REST API.

from aws_cdk import (
    Stack,
    aws_apigateway as apigwv1,
    aws_lambda as lambda_,
    CfnOutput,
    Duration
)
from constructs import Construct

class HelloWorldStack(Stack):

    def __init__(self, scope: Construct, construct_id: str, **kwargs) -> None:
        super().__init__(scope, construct_id, **kwargs)

        # Powertools Lambda Layer
        powertools_layer = lambda_.LayerVersion.from_layer_version_arn(
            self,
            id="lambda-powertools",
            # At the moment we wrote this example, the aws_lambda_python_alpha CDK constructor is in Alpha, o we use layer to make the example simpler
            # See https://docs.aws.amazon.com/cdk/api/v2/python/aws_cdk.aws_lambda_python_alpha/README.html
            # Check all Powertools layers versions here: https://docs.powertools.aws.dev/lambda-python/latest/#lambda-layer
            layer_version_arn=f"arn:aws:lambda:{self.region}:017000801446:layer:AWSLambdaPowertoolsPythonV2:21"
        )

        function = lambda_.Function(self,
            'sample-app-lambda',
            runtime=lambda_.Runtime.PYTHON_3_9,
            layers=[powertools_layer],
            code = lambda_.Code.from_asset("./lambda_function/"),
            handler="app.lambda_handler",
            memory_size=128,
            timeout=Duration.seconds(3),
            architecture=lambda_.Architecture.X86_64,
            environment={
                "POWERTOOLS_SERVICE_NAME": "PowertoolsHelloWorld",
                "POWERTOOLS_METRICS_NAMESPACE": "PowertoolsSample",
                "LOG_LEVEL": "INFO"
            }
        )

        apigw = apigwv1.RestApi(self, "PowertoolsAPI", deploy_options=apigwv1.StageOptions(stage_name="dev"))

        hello_api = apigw.root.add_resource("hello")
        hello_api.add_method("GET", apigwv1.LambdaIntegration(function, proxy=True))

        CfnOutput(self, "apiUrl", value=f"{apigw.url}hello")

Men-deploy aplikasi Anda.

cd ..
cdk deploy

Dapatkan URL aplikasi yang digunakan:

aws cloudformation describe-stacks --stack-name HelloWorldStack --query 'Stacks[0].Outputs[?OutputKey==`apiUrl`].OutputValue' --output text

Memanggil titik akhir API:

curl -X GET <URL_FROM_PREVIOUS_STEP>

Jika berhasil, Anda akan melihat tanggapan ini:

{"message":"hello world"}

Untuk mendapatkan jejak untuk fungsi tersebut, jalankan jejak sam.

sam traces

Output jejak terlihat seperti ini:

New XRay Service Graph
  Start time: 2023-02-03 14:59:50+00:00
  End time: 2023-02-03 14:59:50+00:00
  Reference Id: 0 - (Root) AWS::Lambda - sam-app-HelloWorldFunction-YBg8yfYtOc9j - Edges: [1]
   Summary_statistics:
     - total requests: 1
     - ok count(2XX): 1
     - error count(4XX): 0
     - fault count(5XX): 0
     - total response time: 0.924
  Reference Id: 1 - AWS::Lambda::Function - sam-app-HelloWorldFunction-YBg8yfYtOc9j - Edges: []
   Summary_statistics:
     - total requests: 1
     - ok count(2XX): 1
     - error count(4XX): 0
     - fault count(5XX): 0
     - total response time: 0.016
  Reference Id: 2 - client - sam-app-HelloWorldFunction-YBg8yfYtOc9j - Edges: [0]
   Summary_statistics:
     - total requests: 0
     - ok count(2XX): 0
     - error count(4XX): 0
     - fault count(5XX): 0
     - total response time: 0

XRay Event [revision 1] at (2023-02-03T14:59:50.204000) with id (1-63dd2166-434a12c22e1307ff2114f299) and duration (0.924s)
 - 0.924s - sam-app-HelloWorldFunction-YBg8yfYtOc9j [HTTP: 200]
 - 0.016s - sam-app-HelloWorldFunction-YBg8yfYtOc9j
   - 0.739s - Initialization
   - 0.016s - Invocation
     - 0.013s - ## lambda_handler
       - 0.000s - ## app.hello
   - 0.000s - Overhead

Ini adalah titik akhir API publik yang dapat diakses melalui internet. Kami menyarankan Anda menghapus titik akhir setelah pengujian.

cdk destroy

Buka halaman Fungsi di konsol Lambda.

Pilih fungsi.

Pilih Konfigurasi dan kemudian pilih Alat Pemantauan dan operasi.

Pilih Edit.

Di bawah X-Ray, aktifkan penelusuran Aktif.

Pilih Simpan.