simple-lambda-process.md

To call a Bedrock model, using a Python Lambda Function, follow the steps below:

1. Prerequisites:
   1. From the Bedrock console get access to the specific model in the same region that you are deploying your Lambda function in.
   2. Provide an IAM role to access Bedrock models

PolicyDocument:
Version: "2012-10-17"
Statement: 
- Effect: Allow
Action:
- bedrock:InvokeModel
Resource: !Sub arn:aws:bedrock:${AWS::Region}::foundation-model/*

2. Ensure your Lambda Function time-out is set to 60 secs (can be lower or higher depending on your prompt)
3. Lambda Runtime should be Python 3.9 or higher
4. Have a requirements.txt file with the following included:

boto3==1.28.57

5. Lambda code (to call anthropic.claude-v2 foe example) is as follows:

import os
import json
import boto3

region = os.environ.get('AWS_DEFAULT_REGION')
bedrock = boto3.client(service_name='bedrock-runtime',
                       region_name=region)

model_kwargs = {
                "max_tokens_to_sample": 300,
                "temperature": 1,
                "top_p": 0.9 
               }
               
accept = '*/*'
contentType = 'application/json'

def lambda_handler(event, context):
    prompt = "\n\nHuman:explain black holes to 8th graders in 3 sentences\n\nAssistant:"

    model_kwargs["prompt"] = prompt
    body = json.dumps(model_kwargs)

    print(body)
    modelId = 'anthropic.claude-v2'
    response = bedrock.invoke_model(body=body, modelId=modelId, accept=accept,
                                    contentType=contentType)

    response_body = json.loads(response.get('body').read())
    print(response_body)
    print(response_body.get('completion'))
    return_message = response_body.get('completion')

    return {
        "statusCode": 200,
        "body": json.dumps({
            "message": return_message
        }),
    }