I am trying to build a service where user will upload an image to first s3 bucket. Which will trigger a Lambda function and the function will use amazon rekognition to analyze the image and get the labels. Finally store the output into a second bucket.

After uploading the image, I see this error in CloudWatch log and no output in 2nd bucket. The code that I used for Lambda function and policies for Lambda role, error message is included bellow. I am doing all these using the aws root user. Tried policy simulator, it says with these 3 policies Lambda is allowed to access DetectLabels. Please give me suggestion…

============================================Lambda Code

import boto3
import json

def lambda_handler(event, context):
# Extract the bucket and object key from the S3 event
source_bucket = event[‘Records’][0][‘s3’][‘bucket’][‘name’] source_key = event[‘Records’][0][‘s3’][‘object’][‘key’]

# Create an Amazon Rekognition client
rekognition_client = boto3.client('rekognition')

# Specify the source S3 object for Rekognition
image_source = {'S3Object': {'Bucket': source_bucket, 'Name': source_key}}

try:
    # Detect labels in the image
    response = rekognition_client.detect_labels(Image=image_source)

    # Extract labels from the response
    labels = [{'Name': label['Name'], 'Confidence': label['Confidence']} for label in response['Labels']]

    # Create a new S3 bucket to store the analysis output
    destination_bucket = 'bucket2-lambda-rekognition-100-ca-central1-26nov23'
    destination_key = f'rekognition-analysis/{source_key.split("/")[-1]}'

    # Save the analysis output as JSON to the destination S3 bucket
    s3_client = boto3.client('s3')
    s3_client.put_object(
        Bucket=destination_bucket,
        Key=destination_key,
        Body=json.dumps(labels),
        ContentType='application/json'
    )

    print(f"Image analysis completed. Analysis results saved to {destination_bucket}/{destination_key}")

    return {
        'statusCode': 200,
        'body': 'Image analysis and result storage completed successfully.'
    }

except Exception as e:
    print(f"Error analyzing image: {e}")
    return {
        'statusCode': 500,
        'body': 'Error analyzing image and storing results.'
    }

===========================Policies

Policies attached to the IAM role that is attached to the Lambda function >>

AmazonRekognitionReadOnlyAccess
AmazonS3FullAccess
AWSLambdaBasicExecutionRole

===========================

Error message >>

"Error analyzing image: An error occurred (AccessDeniedException) when calling the DetectLabels operation:"