# Lambda examples using AWS CLI with Bash script
<a name="bash_lambda_code_examples"></a>

The following code examples show you how to perform actions and implement common scenarios by using the AWS Command Line Interface with Bash script with Lambda.

*Scenarios* are code examples that show you how to accomplish specific tasks by calling multiple functions within a service or combined with other AWS services.

Each example includes a link to the complete source code, where you can find instructions on how to set up and run the code in context.

**Topics**
+ [Scenarios](#scenarios)

## Scenarios
<a name="scenarios"></a>

### Create a REST API with Lambda proxy integration
<a name="api_gateway_GettingStarted_087_bash_topic"></a>

The following code example shows how to:
+ Create an IAM role for Lambda execution
+ Create and deploy a Lambda function
+ Create a REST API
+ Configure Lambda proxy integration
+ Deploy and test the API
+ Clean up resources

**AWS CLI with Bash script**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [Sample developer tutorials](https://github.com/aws-samples/sample-developer-tutorials/tree/main/tuts/087-apigateway-lambda-integration) repository. 

```
#!/bin/bash

# Simple API Gateway Lambda Integration Script
# This script creates a REST API with Lambda proxy integration

# Generate random identifiers
FUNCTION_NAME="GetStartedLambdaProxyIntegration-$(openssl rand -hex 4)"
ROLE_NAME="GetStartedLambdaBasicExecutionRole-$(openssl rand -hex 4)"
API_NAME="LambdaProxyAPI-$(openssl rand -hex 4)"

# Get AWS account info
ACCOUNT_ID=$(aws sts get-caller-identity --query Account --output text)
REGION=$(aws configure get region || echo "us-east-1")

echo "Creating Lambda function code..."

# Create Lambda function code
cat > lambda_function.py << 'EOF'
import json

def lambda_handler(event, context):
    print(event)
    
    greeter = 'World'
    
    try:
        if (event['queryStringParameters']) and (event['queryStringParameters']['greeter']) and (
                event['queryStringParameters']['greeter'] is not None):
            greeter = event['queryStringParameters']['greeter']
    except KeyError:
        print('No greeter')
    
    try:
        if (event['multiValueHeaders']) and (event['multiValueHeaders']['greeter']) and (
                event['multiValueHeaders']['greeter'] is not None):
            greeter = " and ".join(event['multiValueHeaders']['greeter'])
    except KeyError:
        print('No greeter')
    
    try:
        if (event['headers']) and (event['headers']['greeter']) and (
                event['headers']['greeter'] is not None):
            greeter = event['headers']['greeter']
    except KeyError:
        print('No greeter')
    
    if (event['body']) and (event['body'] is not None):
        body = json.loads(event['body'])
        try:
            if (body['greeter']) and (body['greeter'] is not None):
                greeter = body['greeter']
        except KeyError:
            print('No greeter')
    
    res = {
        "statusCode": 200,
        "headers": {
            "Content-Type": "*/*"
        },
        "body": "Hello, " + greeter + "!"
    }
    
    return res
EOF

# Create deployment package
zip function.zip lambda_function.py

echo "Creating IAM role..."

# Create IAM trust policy
cat > trust-policy.json << 'EOF'
{
  "Version":"2012-10-17",		 	 	 
  "Statement": [
    {
      "Effect": "Allow",
      "Principal": {
        "Service": "lambda.amazonaws.com"
      },
      "Action": "sts:AssumeRole"
    }
  ]
}
EOF

# Create IAM role
aws iam create-role \
    --role-name "$ROLE_NAME" \
    --assume-role-policy-document file://trust-policy.json

# Attach execution policy
aws iam attach-role-policy \
    --role-name "$ROLE_NAME" \
    --policy-arn "arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole"

# Wait for role propagation
sleep 15

echo "Creating Lambda function..."

# Create Lambda function
aws lambda create-function \
    --function-name "$FUNCTION_NAME" \
    --runtime python3.9 \
    --role "arn:aws:iam::$ACCOUNT_ID:role/$ROLE_NAME" \
    --handler lambda_function.lambda_handler \
    --zip-file fileb://function.zip

echo "Creating API Gateway..."

# Create REST API
aws apigateway create-rest-api \
    --name "$API_NAME" \
    --endpoint-configuration types=REGIONAL

# Get API ID
API_ID=$(aws apigateway get-rest-apis --query "items[?name=='$API_NAME'].id" --output text)

# Get root resource ID
ROOT_RESOURCE_ID=$(aws apigateway get-resources --rest-api-id "$API_ID" --query 'items[?path==`/`].id' --output text)

# Create helloworld resource
aws apigateway create-resource \
    --rest-api-id "$API_ID" \
    --parent-id "$ROOT_RESOURCE_ID" \
    --path-part helloworld

# Get resource ID
RESOURCE_ID=$(aws apigateway get-resources --rest-api-id "$API_ID" --query "items[?pathPart=='helloworld'].id" --output text)

# Create ANY method
aws apigateway put-method \
    --rest-api-id "$API_ID" \
    --resource-id "$RESOURCE_ID" \
    --http-method ANY \
    --authorization-type NONE

# Set up Lambda proxy integration
LAMBDA_URI="arn:aws:apigateway:$REGION:lambda:path/2015-03-31/functions/arn:aws:lambda:$REGION:$ACCOUNT_ID:function:$FUNCTION_NAME/invocations"

aws apigateway put-integration \
    --rest-api-id "$API_ID" \
    --resource-id "$RESOURCE_ID" \
    --http-method ANY \
    --type AWS_PROXY \
    --integration-http-method POST \
    --uri "$LAMBDA_URI"

# Grant API Gateway permission to invoke Lambda
SOURCE_ARN="arn:aws:execute-api:$REGION:$ACCOUNT_ID:$API_ID/*/*"

aws lambda add-permission \
    --function-name "$FUNCTION_NAME" \
    --statement-id "apigateway-invoke-$(openssl rand -hex 4)" \
    --action lambda:InvokeFunction \
    --principal apigateway.amazonaws.com \
    --source-arn "$SOURCE_ARN"

# Deploy API
aws apigateway create-deployment \
    --rest-api-id "$API_ID" \
    --stage-name test

echo "Testing API..."

# Test the API
INVOKE_URL="https://$API_ID.execute-api.$REGION.amazonaws.com/test/helloworld"

echo "API URL: $INVOKE_URL"

# Test with query parameter
echo "Testing with query parameter:"
curl -X GET "$INVOKE_URL?greeter=John"
echo ""

# Test with header
echo "Testing with header:"
curl -X GET "$INVOKE_URL" \
    -H 'content-type: application/json' \
    -H 'greeter: John'
echo ""

# Test with body
echo "Testing with POST body:"
curl -X POST "$INVOKE_URL" \
    -H 'content-type: application/json' \
    -d '{ "greeter": "John" }'
echo ""

echo "Tutorial completed! API is available at: $INVOKE_URL"

# Cleanup
echo "Cleaning up resources..."

# Delete API
aws apigateway delete-rest-api --rest-api-id "$API_ID"

# Delete Lambda function
aws lambda delete-function --function-name "$FUNCTION_NAME"

# Detach policy and delete role
aws iam detach-role-policy \
    --role-name "$ROLE_NAME" \
    --policy-arn "arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole"

aws iam delete-role --role-name "$ROLE_NAME"

# Clean up local files
rm -f lambda_function.py function.zip trust-policy.json

echo "Cleanup completed!"
```
+ For API details, see the following topics in *AWS CLI Command Reference*.
  + [AddPermission](https://docs.aws.amazon.com/goto/aws-cli/lambda-2015-03-31/AddPermission)
  + [AttachRolePolicy](https://docs.aws.amazon.com/goto/aws-cli/iam-2010-05-08/AttachRolePolicy)
  + [CreateDeployment](https://docs.aws.amazon.com/goto/aws-cli/apigateway-2015-07-09/CreateDeployment)
  + [CreateFunction](https://docs.aws.amazon.com/goto/aws-cli/lambda-2015-03-31/CreateFunction)
  + [CreateResource](https://docs.aws.amazon.com/goto/aws-cli/apigateway-2015-07-09/CreateResource)
  + [CreateRestApi](https://docs.aws.amazon.com/goto/aws-cli/apigateway-2015-07-09/CreateRestApi)
  + [CreateRole](https://docs.aws.amazon.com/goto/aws-cli/iam-2010-05-08/CreateRole)
  + [DeleteFunction](https://docs.aws.amazon.com/goto/aws-cli/lambda-2015-03-31/DeleteFunction)
  + [DeleteRestApi](https://docs.aws.amazon.com/goto/aws-cli/apigateway-2015-07-09/DeleteRestApi)
  + [DeleteRole](https://docs.aws.amazon.com/goto/aws-cli/iam-2010-05-08/DeleteRole)
  + [DetachRolePolicy](https://docs.aws.amazon.com/goto/aws-cli/iam-2010-05-08/DetachRolePolicy)
  + [GetCallerIdentity](https://docs.aws.amazon.com/goto/aws-cli/sts-2011-06-15/GetCallerIdentity)
  + [GetResources](https://docs.aws.amazon.com/goto/aws-cli/apigateway-2015-07-09/GetResources)
  + [GetRestApis](https://docs.aws.amazon.com/goto/aws-cli/apigateway-2015-07-09/GetRestApis)
  + [PutIntegration](https://docs.aws.amazon.com/goto/aws-cli/apigateway-2015-07-09/PutIntegration)
  + [PutMethod](https://docs.aws.amazon.com/goto/aws-cli/apigateway-2015-07-09/PutMethod)

### Creating a CloudWatch dashboard with function name as a variable
<a name="cloudwatch_GettingStarted_031_bash_topic"></a>

The following code example shows how to:
+ Create a CloudWatch dashboard
+ Add Lambda metrics widgets with a function name variable
+ Verify the dashboard
+ Clean up resources

**AWS CLI with Bash script**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [Sample developer tutorials](https://github.com/aws-samples/sample-developer-tutorials/tree/main/tuts/031-cloudwatch-dynamicdash) repository. 

```
#!/bin/bash

# Script to create a CloudWatch dashboard with Lambda function name as a variable
# This script creates a CloudWatch dashboard that allows you to switch between different Lambda functions

# Set up logging
LOG_FILE="cloudwatch-dashboard-script.log"
exec > >(tee -a "$LOG_FILE") 2>&1

echo "$(date): Starting CloudWatch dashboard creation script"

# Function to handle errors
handle_error() {
    echo "ERROR: $1"
    echo "Resources created:"
    echo "- CloudWatch Dashboard: LambdaMetricsDashboard"
    echo ""
    echo "==========================================="
    echo "CLEANUP CONFIRMATION"
    echo "==========================================="
    echo "An error occurred. Do you want to clean up the created resources? (y/n): "
    read -r CLEANUP_CHOICE
    
    if [[ "${CLEANUP_CHOICE,,}" == "y" ]]; then
        echo "Cleaning up resources..."
        aws cloudwatch delete-dashboards --dashboard-names LambdaMetricsDashboard
        echo "Cleanup complete."
    else
        echo "Resources were not cleaned up. You can manually delete them later."
    fi
    exit 1
}

# Check if AWS CLI is installed and configured
echo "Checking AWS CLI configuration..."
aws sts get-caller-identity > /dev/null 2>&1
if [ $? -ne 0 ]; then
    handle_error "AWS CLI is not properly configured. Please configure it with 'aws configure' and try again."
fi

# Get the current region
REGION=$(aws configure get region)
if [ -z "$REGION" ]; then
    REGION="us-east-1"
    echo "No region found in AWS config, defaulting to $REGION"
fi
echo "Using region: $REGION"

# Check if there are any Lambda functions in the account
echo "Checking for Lambda functions..."
LAMBDA_FUNCTIONS=$(aws lambda list-functions --query "Functions[*].FunctionName" --output text)
if [ -z "$LAMBDA_FUNCTIONS" ]; then
    echo "No Lambda functions found in your account. Creating a simple test function..."
    
    # Create a temporary directory for Lambda function code
    TEMP_DIR=$(mktemp -d)
    
    # Create a simple Lambda function
    cat > "$TEMP_DIR/index.js" << EOF
exports.handler = async (event) => {
    console.log('Event:', JSON.stringify(event, null, 2));
    return {
        statusCode: 200,
        body: JSON.stringify('Hello from Lambda!'),
    };
};
EOF
    
    # Zip the function code
    cd "$TEMP_DIR" || handle_error "Failed to change to temporary directory"
    zip -q function.zip index.js
    
    # Create a role for the Lambda function
    ROLE_NAME="LambdaDashboardTestRole"
    ROLE_ARN=$(aws iam create-role \
        --role-name "$ROLE_NAME" \
        --assume-role-policy-document '{"Version":"2012-10-17",		 	 	 "Statement":[{"Effect":"Allow","Principal":{"Service":"lambda.amazonaws.com"},"Action":"sts:AssumeRole"}]}' \
        --query "Role.Arn" \
        --output text)
    
    if [ $? -ne 0 ]; then
        handle_error "Failed to create IAM role for Lambda function"
    fi
    
    echo "Waiting for role to be available..."
    sleep 10
    
    # Attach basic Lambda execution policy
    aws iam attach-role-policy \
        --role-name "$ROLE_NAME" \
        --policy-arn "arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole"
    
    if [ $? -ne 0 ]; then
        aws iam delete-role --role-name "$ROLE_NAME"
        handle_error "Failed to attach policy to IAM role"
    fi
    
    # Create the Lambda function
    FUNCTION_NAME="DashboardTestFunction"
    aws lambda create-function \
        --function-name "$FUNCTION_NAME" \
        --runtime nodejs18.x \
        --role "$ROLE_ARN" \
        --handler index.handler \
        --zip-file fileb://function.zip
    
    if [ $? -ne 0 ]; then
        aws iam detach-role-policy \
            --role-name "$ROLE_NAME" \
            --policy-arn "arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole"
        aws iam delete-role --role-name "$ROLE_NAME"
        handle_error "Failed to create Lambda function"
    fi
    
    # Invoke the function to generate some metrics
    echo "Invoking Lambda function to generate metrics..."
    for i in {1..5}; do
        aws lambda invoke --function-name "$FUNCTION_NAME" --payload '{}' /dev/null > /dev/null
        sleep 1
    done
    
    # Clean up temporary directory
    cd - > /dev/null
    rm -rf "$TEMP_DIR"
    
    # Set the function name for the dashboard
    DEFAULT_FUNCTION="$FUNCTION_NAME"
else
    # Use the first Lambda function as default
    DEFAULT_FUNCTION=$(echo "$LAMBDA_FUNCTIONS" | awk '{print $1}')
    echo "Found Lambda functions. Using $DEFAULT_FUNCTION as default."
fi

# Create a dashboard with Lambda metrics and a function name variable
echo "Creating CloudWatch dashboard with Lambda function name variable..."

# Create a JSON file for the dashboard body
cat > dashboard-body.json << EOF
{
  "widgets": [
    {
      "type": "metric",
      "x": 0,
      "y": 0,
      "width": 12,
      "height": 6,
      "properties": {
        "metrics": [
          [ "AWS/Lambda", "Invocations", "FunctionName", "\${FunctionName}" ],
          [ ".", "Errors", ".", "." ],
          [ ".", "Throttles", ".", "." ]
        ],
        "view": "timeSeries",
        "stacked": false,
        "region": "$REGION",
        "title": "Lambda Function Metrics for \${FunctionName}",
        "period": 300
      }
    },
    {
      "type": "metric",
      "x": 0,
      "y": 6,
      "width": 12,
      "height": 6,
      "properties": {
        "metrics": [
          [ "AWS/Lambda", "Duration", "FunctionName", "\${FunctionName}", { "stat": "Average" } ]
        ],
        "view": "timeSeries",
        "stacked": false,
        "region": "$REGION",
        "title": "Duration for \${FunctionName}",
        "period": 300
      }
    },
    {
      "type": "metric",
      "x": 12,
      "y": 0,
      "width": 12,
      "height": 6,
      "properties": {
        "metrics": [
          [ "AWS/Lambda", "ConcurrentExecutions", "FunctionName", "\${FunctionName}" ]
        ],
        "view": "timeSeries",
        "stacked": false,
        "region": "$REGION",
        "title": "Concurrent Executions for \${FunctionName}",
        "period": 300
      }
    }
  ],
  "periodOverride": "auto",
  "variables": [
    {
      "type": "property",
      "id": "FunctionName",
      "property": "FunctionName",
      "label": "Lambda Function",
      "inputType": "select",
      "values": [
        {
          "value": "$DEFAULT_FUNCTION",
          "label": "$DEFAULT_FUNCTION"
        }
      ]
    }
  ]
}
EOF

# Create the dashboard using the JSON file
DASHBOARD_RESULT=$(aws cloudwatch put-dashboard --dashboard-name LambdaMetricsDashboard --dashboard-body file://dashboard-body.json)
DASHBOARD_EXIT_CODE=$?

# Check if there was a fatal error
if [ $DASHBOARD_EXIT_CODE -ne 0 ]; then
    # If we created resources, clean them up
    if [ -n "${FUNCTION_NAME:-}" ]; then
        aws lambda delete-function --function-name "$FUNCTION_NAME"
        aws iam detach-role-policy \
            --role-name "$ROLE_NAME" \
            --policy-arn "arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole"
        aws iam delete-role --role-name "$ROLE_NAME"
    fi
    handle_error "Failed to create CloudWatch dashboard."
fi

# Display any validation messages but continue
if [[ "$DASHBOARD_RESULT" == *"DashboardValidationMessages"* ]]; then
    echo "Dashboard created with validation messages:"
    echo "$DASHBOARD_RESULT"
    echo "These validation messages are warnings and the dashboard should still function."
else
    echo "Dashboard created successfully!"
fi

# Verify the dashboard was created
echo "Verifying dashboard creation..."
DASHBOARD_INFO=$(aws cloudwatch get-dashboard --dashboard-name LambdaMetricsDashboard)
DASHBOARD_INFO_EXIT_CODE=$?

if [ $DASHBOARD_INFO_EXIT_CODE -ne 0 ]; then
    # If we created resources, clean them up
    if [ -n "${FUNCTION_NAME:-}" ]; then
        aws lambda delete-function --function-name "$FUNCTION_NAME"
        aws iam detach-role-policy \
            --role-name "$ROLE_NAME" \
            --policy-arn "arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole"
        aws iam delete-role --role-name "$ROLE_NAME"
    fi
    handle_error "Failed to verify dashboard creation."
fi

echo "Dashboard verification successful!"
echo "Dashboard details:"
echo "$DASHBOARD_INFO"

# List all dashboards to confirm
echo "Listing all dashboards:"
DASHBOARDS=$(aws cloudwatch list-dashboards)
DASHBOARDS_EXIT_CODE=$?

if [ $DASHBOARDS_EXIT_CODE -ne 0 ]; then
    # If we created resources, clean them up
    if [ -n "${FUNCTION_NAME:-}" ]; then
        aws lambda delete-function --function-name "$FUNCTION_NAME"
        aws iam detach-role-policy \
            --role-name "$ROLE_NAME" \
            --policy-arn "arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole"
        aws iam delete-role --role-name "$ROLE_NAME"
    fi
    handle_error "Failed to list dashboards."
fi
echo "$DASHBOARDS"

# Show instructions for accessing the dashboard
echo ""
echo "Dashboard created successfully! To access it:"
echo "1. Open the CloudWatch console at https://console.aws.amazon.com/cloudwatch/"
echo "2. In the navigation pane, choose Dashboards"
echo "3. Select LambdaMetricsDashboard"
echo "4. You should see a dropdown menu labeled 'Lambda Function' at the top of the dashboard"
echo "5. Use this dropdown to select different Lambda functions and see their metrics"
echo ""

# Create a list of resources for cleanup
RESOURCES=("- CloudWatch Dashboard: LambdaMetricsDashboard")
if [ -n "${FUNCTION_NAME:-}" ]; then
    RESOURCES+=("- Lambda Function: $FUNCTION_NAME")
    RESOURCES+=("- IAM Role: $ROLE_NAME")
fi

# Prompt for cleanup
echo "==========================================="
echo "CLEANUP CONFIRMATION"
echo "==========================================="
echo "Resources created:"
for resource in "${RESOURCES[@]}"; do
    echo "$resource"
done
echo ""
echo "Do you want to clean up all created resources? (y/n): "
read -r CLEANUP_CHOICE

if [[ "${CLEANUP_CHOICE,,}" == "y" ]]; then
    echo "Cleaning up resources..."
    
    # Delete the dashboard
    aws cloudwatch delete-dashboards --dashboard-names LambdaMetricsDashboard
    if [ $? -ne 0 ]; then
        echo "WARNING: Failed to delete dashboard. You may need to delete it manually."
    else
        echo "Dashboard deleted successfully."
    fi
    
    # If we created a Lambda function, delete it and its role
    if [ -n "${FUNCTION_NAME:-}" ]; then
        echo "Deleting Lambda function..."
        aws lambda delete-function --function-name "$FUNCTION_NAME"
        if [ $? -ne 0 ]; then
            echo "WARNING: Failed to delete Lambda function. You may need to delete it manually."
        else
            echo "Lambda function deleted successfully."
        fi
        
        echo "Detaching role policy..."
        aws iam detach-role-policy \
            --role-name "$ROLE_NAME" \
            --policy-arn "arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole"
        if [ $? -ne 0 ]; then
            echo "WARNING: Failed to detach role policy. You may need to detach it manually."
        else
            echo "Role policy detached successfully."
        fi
        
        echo "Deleting IAM role..."
        aws iam delete-role --role-name "$ROLE_NAME"
        if [ $? -ne 0 ]; then
            echo "WARNING: Failed to delete IAM role. You may need to delete it manually."
        else
            echo "IAM role deleted successfully."
        fi
    fi
    
    # Clean up the JSON file
    rm -f dashboard-body.json
    
    echo "Cleanup complete."
else
    echo "Resources were not cleaned up. You can manually delete them later with:"
    echo "aws cloudwatch delete-dashboards --dashboard-names LambdaMetricsDashboard"
    if [ -n "${FUNCTION_NAME:-}" ]; then
        echo "aws lambda delete-function --function-name $FUNCTION_NAME"
        echo "aws iam detach-role-policy --role-name $ROLE_NAME --policy-arn arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole"
        echo "aws iam delete-role --role-name $ROLE_NAME"
    fi
fi

echo "Script completed successfully!"
```
+ For API details, see the following topics in *AWS CLI Command Reference*.
  + [AttachRolePolicy](https://docs.aws.amazon.com/goto/aws-cli/iam-2010-05-08/AttachRolePolicy)
  + [CreateFunction](https://docs.aws.amazon.com/goto/aws-cli/lambda-2015-03-31/CreateFunction)
  + [CreateRole](https://docs.aws.amazon.com/goto/aws-cli/iam-2010-05-08/CreateRole)
  + [DeleteDashboards](https://docs.aws.amazon.com/goto/aws-cli/monitoring-2010-08-01/DeleteDashboards)
  + [DeleteFunction](https://docs.aws.amazon.com/goto/aws-cli/lambda-2015-03-31/DeleteFunction)
  + [DeleteRole](https://docs.aws.amazon.com/goto/aws-cli/iam-2010-05-08/DeleteRole)
  + [DetachRolePolicy](https://docs.aws.amazon.com/goto/aws-cli/iam-2010-05-08/DetachRolePolicy)
  + [GetCallerIdentity](https://docs.aws.amazon.com/goto/aws-cli/sts-2011-06-15/GetCallerIdentity)
  + [GetDashboard](https://docs.aws.amazon.com/goto/aws-cli/monitoring-2010-08-01/GetDashboard)
  + [Invoke](https://docs.aws.amazon.com/goto/aws-cli/lambda-2015-03-31/Invoke)
  + [ListDashboards](https://docs.aws.amazon.com/goto/aws-cli/monitoring-2010-08-01/ListDashboards)
  + [ListFunctions](https://docs.aws.amazon.com/goto/aws-cli/lambda-2015-03-31/ListFunctions)
  + [PutDashboard](https://docs.aws.amazon.com/goto/aws-cli/monitoring-2010-08-01/PutDashboard)

### Creating your first Lambda function
<a name="lambda_GettingStarted_019_bash_topic"></a>

The following code example shows how to:
+ Create an IAM role for Lambda
+ Create function code
+ Create a Lambda function
+ Test your Lambda function
+ Clean up resources

**AWS CLI with Bash script**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [Sample developer tutorials](https://github.com/aws-samples/sample-developer-tutorials/tree/main/tuts/019-lambda-gettingstarted) repository. 

```
#!/bin/bash
# AWS Lambda - Create Your First Function
# This script creates a Lambda function, invokes it with a test event,
# views CloudWatch logs, and cleans up all resources.
#
# Source: https://docs.aws.amazon.com/lambda/latest/dg/getting-started.html
#
# Resources created:
#   - IAM role (Lambda execution role with basic logging permissions)
#   - Lambda function (Python 3.13 or Node.js 22.x runtime)
#   - CloudWatch log group (created automatically by Lambda on invocation)

set -eE

###############################################################################
# Setup
###############################################################################

UNIQUE_ID=$(cat /dev/urandom | tr -dc 'a-z0-9' | fold -w 8 | head -n 1)
FUNCTION_NAME="my-lambda-function-${UNIQUE_ID}"
ROLE_NAME="lambda-execution-role-${UNIQUE_ID}"
LOG_GROUP_NAME="/aws/lambda/${FUNCTION_NAME}"

TEMP_DIR=$(mktemp -d)
LOG_FILE="${TEMP_DIR}/lambda-gettingstarted.log"

exec > >(tee -a "$LOG_FILE") 2>&1

declare -a CREATED_RESOURCES

###############################################################################
# Helper functions
###############################################################################

cleanup_resources() {
    # Disable error trap to prevent recursion during cleanup
    trap - ERR
    set +eE

    echo ""
    echo "Cleaning up resources..."
    echo ""

    for ((i=${#CREATED_RESOURCES[@]}-1; i>=0; i--)); do
        local RESOURCE="${CREATED_RESOURCES[$i]}"
        local TYPE="${RESOURCE%%:*}"
        local NAME="${RESOURCE#*:}"

        case "$TYPE" in
            log-group)
                echo "Deleting CloudWatch log group: ${NAME}"
                aws logs delete-log-group \
                    --log-group-name "$NAME" 2>&1 || echo "  WARNING: Could not delete log group ${NAME}."
                ;;
            lambda-function)
                echo "Deleting Lambda function: ${NAME}"
                aws lambda delete-function \
                    --function-name "$NAME" 2>&1 || echo "  WARNING: Could not delete Lambda function ${NAME}."
                echo "  Waiting for function deletion to complete..."
                local DELETE_WAIT=0
                while aws lambda get-function --function-name "$NAME" > /dev/null 2>&1; do
                    sleep 2
                    DELETE_WAIT=$((DELETE_WAIT + 2))
                    if [ "$DELETE_WAIT" -ge 60 ]; then
                        echo "  WARNING: Timed out waiting for function deletion."
                        break
                    fi
                done
                ;;
            iam-role-policy)
                local ROLE_PART="${NAME%%|*}"
                local POLICY_PART="${NAME#*|}"
                echo "Detaching policy from role: ${ROLE_PART}"
                aws iam detach-role-policy \
                    --role-name "$ROLE_PART" \
                    --policy-arn "$POLICY_PART" 2>&1 || echo "  WARNING: Could not detach policy from role ${ROLE_PART}."
                ;;
            iam-role)
                echo "Deleting IAM role: ${NAME}"
                aws iam delete-role \
                    --role-name "$NAME" 2>&1 || echo "  WARNING: Could not delete IAM role ${NAME}."
                ;;
        esac
    done

    if [ -d "$TEMP_DIR" ]; then
        rm -rf "$TEMP_DIR"
    fi

    echo ""
    echo "Cleanup complete."
}

handle_error() {
    echo ""
    echo "==========================================="
    echo "ERROR: Script failed at $1"
    echo "==========================================="
    echo ""
    if [ ${#CREATED_RESOURCES[@]} -gt 0 ]; then
        echo "Attempting to clean up ${#CREATED_RESOURCES[@]} resource(s)..."
        cleanup_resources
    fi
    exit 1
}

trap 'handle_error "line $LINENO"' ERR

wait_for_resource() {
    local DESCRIPTION="$1"
    local COMMAND="$2"
    local TARGET_VALUE="$3"
    local TIMEOUT=300
    local ELAPSED=0
    local INTERVAL=5

    echo "Waiting for ${DESCRIPTION}..."
    while true; do
        local RESULT
        RESULT=$(eval "$COMMAND" 2>&1) || true
        if echo "$RESULT" | grep -q "$TARGET_VALUE"; then
            echo "  ${DESCRIPTION} is ready."
            return 0
        fi
        if [ "$ELAPSED" -ge "$TIMEOUT" ]; then
            echo "ERROR: Timed out waiting for ${DESCRIPTION} after ${TIMEOUT} seconds."
            return 1
        fi
        sleep "$INTERVAL"
        ELAPSED=$((ELAPSED + INTERVAL))
    done
}

###############################################################################
# Region pre-check
###############################################################################

CONFIGURED_REGION=$(aws configure get region 2>/dev/null || true)
if [ -z "$CONFIGURED_REGION" ] && [ -z "$AWS_DEFAULT_REGION" ] && [ -z "$AWS_REGION" ]; then
    echo "ERROR: No AWS region configured."
    echo "Run 'aws configure set region <region>' or export AWS_DEFAULT_REGION."
    exit 1
fi

###############################################################################
# Runtime selection
###############################################################################

echo ""
echo "==========================================="
echo "AWS Lambda - Create Your First Function"
echo "==========================================="
echo ""
echo "Select a runtime for your Lambda function:"
echo "  1) Python 3.13"
echo "  2) Node.js 22.x"
echo ""
echo "Enter your choice (1 or 2): "
read -r RUNTIME_CHOICE

case "$RUNTIME_CHOICE" in
    1)
        RUNTIME="python3.13"
        HANDLER="lambda_function.lambda_handler"
        CODE_FILE="lambda_function.py"
        cat > "${TEMP_DIR}/${CODE_FILE}" << 'PYTHON_EOF'
import json
import logging
logger = logging.getLogger()
logger.setLevel(logging.INFO)
def lambda_handler(event, context):
    length = event['length']
    width = event['width']
    area = calculate_area(length, width)
    print(f'The area is {area}')
    logger.info(f'CloudWatch logs group: {context.log_group_name}')
    return json.dumps({'area': area})
def calculate_area(length, width):
    return length * width
PYTHON_EOF
        echo "Selected runtime: Python 3.13"
        ;;
    2)
        RUNTIME="nodejs22.x"
        HANDLER="index.handler"
        CODE_FILE="index.mjs"
        cat > "${TEMP_DIR}/${CODE_FILE}" << 'NODEJS_EOF'
export const handler = async (event, context) => {
  const area = event.length * event.width;
  console.log(`The area is ${area}`);
  console.log('CloudWatch log group: ', context.logGroupName);
  return JSON.stringify({area});
};
NODEJS_EOF
        echo "Selected runtime: Node.js 22.x"
        ;;
    *)
        echo "ERROR: Invalid choice. Please enter 1 or 2."
        exit 1
        ;;
esac

###############################################################################
# Step 1: Create IAM execution role
###############################################################################

echo ""
echo "==========================================="
echo "Step 1: Create IAM execution role"
echo "==========================================="
echo ""

TRUST_POLICY='{
    "Version":"2012-10-17",		 	 	 
    "Statement": [
        {
            "Effect": "Allow",
            "Principal": {
                "Service": "lambda.amazonaws.com"
            },
            "Action": "sts:AssumeRole"
        }
    ]
}'

echo "Creating IAM role: ${ROLE_NAME}"
ROLE_OUTPUT=$(aws iam create-role \
    --role-name "$ROLE_NAME" \
    --assume-role-policy-document "$TRUST_POLICY" \
    --query 'Role.Arn' \
    --output text 2>&1)
echo "$ROLE_OUTPUT"
ROLE_ARN="$ROLE_OUTPUT"
CREATED_RESOURCES+=("iam-role:${ROLE_NAME}")
echo "Role ARN: ${ROLE_ARN}"

echo ""
echo "Attaching AWSLambdaBasicExecutionRole policy..."
aws iam attach-role-policy \
    --role-name "$ROLE_NAME" \
    --policy-arn "arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole" 2>&1
CREATED_RESOURCES+=("iam-role-policy:${ROLE_NAME}|arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole")
echo "Policy attached."

# IAM roles can take a few seconds to propagate
echo "Waiting for IAM role to propagate..."
sleep 10

###############################################################################
# Step 2: Create Lambda function
###############################################################################

echo ""
echo "==========================================="
echo "Step 2: Create Lambda function"
echo "==========================================="
echo ""

echo "Creating deployment package..."
ORIGINAL_DIR=$(pwd)
cd "$TEMP_DIR"
zip -j function.zip "$CODE_FILE" > /dev/null 2>&1
cd "$ORIGINAL_DIR"

echo "Creating Lambda function: ${FUNCTION_NAME}"
echo "  Runtime: ${RUNTIME}"
echo "  Handler: ${HANDLER}"
echo ""

CREATE_OUTPUT=$(aws lambda create-function \
    --function-name "$FUNCTION_NAME" \
    --runtime "$RUNTIME" \
    --role "$ROLE_ARN" \
    --handler "$HANDLER" \
    --architectures x86_64 \
    --zip-file "fileb://${TEMP_DIR}/function.zip" \
    --query '[FunctionName, FunctionArn, Runtime, State]' \
    --output text 2>&1)
echo "$CREATE_OUTPUT"
CREATED_RESOURCES+=("lambda-function:${FUNCTION_NAME}")

wait_for_resource "Lambda function to become Active" \
    "aws lambda get-function-configuration --function-name ${FUNCTION_NAME} --query State --output text" \
    "Active"

###############################################################################
# Step 3: Invoke the function
###############################################################################

echo ""
echo "==========================================="
echo "Step 3: Invoke the function"
echo "==========================================="
echo ""

TEST_EVENT='{"length": 6, "width": 7}'
echo "Invoking function with test event: ${TEST_EVENT}"
echo ""

echo "$TEST_EVENT" > "${TEMP_DIR}/test-event.json"

INVOKE_OUTPUT=$(aws lambda invoke \
    --function-name "$FUNCTION_NAME" \
    --payload "fileb://${TEMP_DIR}/test-event.json" \
    --cli-read-timeout 30 \
    "${TEMP_DIR}/response.json" 2>&1)
echo "$INVOKE_OUTPUT"

RESPONSE=$(cat "${TEMP_DIR}/response.json")
echo ""
echo "Function response: ${RESPONSE}"
echo ""

if echo "$INVOKE_OUTPUT" | grep -qi "functionerror"; then
    echo "WARNING: Function returned an error."
fi

###############################################################################
# Step 4: View CloudWatch logs
###############################################################################

echo ""
echo "==========================================="
echo "Step 4: View CloudWatch Logs"
echo "==========================================="
echo ""

echo "Log group: ${LOG_GROUP_NAME}"
echo ""

echo "Waiting for CloudWatch logs to be available..."

LOG_STREAMS=""
for i in $(seq 1 6); do
    LOG_STREAMS=$(aws logs describe-log-streams \
        --log-group-name "$LOG_GROUP_NAME" \
        --order-by LastEventTime \
        --descending \
        --query 'logStreams[0].logStreamName' \
        --output text 2>/dev/null) || true
    if [ -n "$LOG_STREAMS" ] && [ "$LOG_STREAMS" != "None" ]; then
        break
    fi
    LOG_STREAMS=""
    sleep 5
done

if [ -n "$LOG_STREAMS" ] && [ "$LOG_STREAMS" != "None" ]; then
    echo "Latest log stream: ${LOG_STREAMS}"
    echo ""
    echo "--- Log events ---"
    LOG_EVENTS=$(aws logs get-log-events \
        --log-group-name "$LOG_GROUP_NAME" \
        --log-stream-name "$LOG_STREAMS" \
        --query 'events[].message' \
        --output text 2>&1) || true
    echo "$LOG_EVENTS"
    echo "--- End of log events ---"
else
    echo "No log streams found yet. Logs may take a moment to appear."
    echo "You can view them in the CloudWatch console:"
    echo "  Log group: ${LOG_GROUP_NAME}"
fi

CREATED_RESOURCES+=("log-group:${LOG_GROUP_NAME}")

###############################################################################
# Summary and cleanup
###############################################################################

echo ""
echo "==========================================="
echo "SUMMARY"
echo "==========================================="
echo ""
echo "Resources created:"
echo "  IAM role:          ${ROLE_NAME}"
echo "  Lambda function:   ${FUNCTION_NAME}"
echo "  CloudWatch logs:   ${LOG_GROUP_NAME}"
echo ""
echo "==========================================="
echo "CLEANUP CONFIRMATION"
echo "==========================================="
echo ""
echo "Do you want to clean up all created resources? (y/n): "
read -r CLEANUP_CHOICE

if [[ "$CLEANUP_CHOICE" =~ ^[Yy]$ ]]; then
    cleanup_resources
else
    echo ""
    echo "Resources were NOT deleted. To clean up manually, run:"
    echo ""
    echo "  # Delete the Lambda function"
    echo "  aws lambda delete-function --function-name ${FUNCTION_NAME}"
    echo ""
    echo "  # Delete the CloudWatch log group"
    echo "  aws logs delete-log-group --log-group-name ${LOG_GROUP_NAME}"
    echo ""
    echo "  # Detach the policy and delete the IAM role"
    echo "  aws iam detach-role-policy --role-name ${ROLE_NAME} --policy-arn arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole"
    echo "  aws iam delete-role --role-name ${ROLE_NAME}"
    echo ""

    if [ -d "$TEMP_DIR" ]; then
        rm -rf "$TEMP_DIR"
    fi
fi

echo ""
echo "Done."
```
+ For API details, see the following topics in *AWS CLI Command Reference*.
  + [AttachRolePolicy](https://docs.aws.amazon.com/goto/aws-cli/iam-2010-05-08/AttachRolePolicy)
  + [CreateFunction](https://docs.aws.amazon.com/goto/aws-cli/lambda-2015-03-31/CreateFunction)
  + [CreateRole](https://docs.aws.amazon.com/goto/aws-cli/iam-2010-05-08/CreateRole)
  + [DeleteFunction](https://docs.aws.amazon.com/goto/aws-cli/lambda-2015-03-31/DeleteFunction)
  + [DeleteLogGroup](https://docs.aws.amazon.com/goto/aws-cli/logs-2014-03-28/DeleteLogGroup)
  + [DeleteRole](https://docs.aws.amazon.com/goto/aws-cli/iam-2010-05-08/DeleteRole)
  + [DescribeLogStreams](https://docs.aws.amazon.com/goto/aws-cli/logs-2014-03-28/DescribeLogStreams)
  + [DetachRolePolicy](https://docs.aws.amazon.com/goto/aws-cli/iam-2010-05-08/DetachRolePolicy)
  + [GetFunction](https://docs.aws.amazon.com/goto/aws-cli/lambda-2015-03-31/GetFunction)
  + [GetFunctionConfiguration](https://docs.aws.amazon.com/goto/aws-cli/lambda-2015-03-31/GetFunctionConfiguration)
  + [GetLogEvents](https://docs.aws.amazon.com/goto/aws-cli/logs-2014-03-28/GetLogEvents)
  + [Invoke](https://docs.aws.amazon.com/goto/aws-cli/lambda-2015-03-31/Invoke)

### Using property variables in CloudWatch dashboards to monitor multiple Lambda functions
<a name="iam_GettingStarted_032_bash_topic"></a>

The following code example shows how to:
+ Create Lambda functions for monitoring
+ Create a CloudWatch dashboard
+ Add a property variable to the dashboard
+ Clean up resources

**AWS CLI with Bash script**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [Sample developer tutorials](https://github.com/aws-samples/sample-developer-tutorials/tree/main/tuts/032-cloudwatch-streams) repository. 

```
#!/bin/bash

# CloudWatch Dashboard with Lambda Function Variable Script
# This script creates a CloudWatch dashboard with a property variable for Lambda function names

# Set up logging
LOG_FILE="cloudwatch-dashboard-script-v4.log"
echo "Starting script execution at $(date)" > "$LOG_FILE"

# Function to log commands and their output
log_cmd() {
    echo "$(date): Running command: $1" >> "$LOG_FILE"
    eval "$1" 2>&1 | tee -a "$LOG_FILE"
    return ${PIPESTATUS[0]}
}

# Function to check for errors in command output
check_error() {
    local cmd_output="$1"
    local cmd_status="$2"
    local error_msg="$3"
    
    if [ $cmd_status -ne 0 ] || echo "$cmd_output" | grep -i "error" > /dev/null; then
        echo "ERROR: $error_msg" | tee -a "$LOG_FILE"
        echo "Command output: $cmd_output" | tee -a "$LOG_FILE"
        cleanup_resources
        exit 1
    fi
}

# Function to clean up resources
cleanup_resources() {
    echo "" | tee -a "$LOG_FILE"
    echo "==========================================" | tee -a "$LOG_FILE"
    echo "CLEANUP PROCESS" | tee -a "$LOG_FILE"
    echo "==========================================" | tee -a "$LOG_FILE"
    
    if [ -n "$DASHBOARD_NAME" ]; then
        echo "Deleting CloudWatch dashboard: $DASHBOARD_NAME" | tee -a "$LOG_FILE"
        log_cmd "aws cloudwatch delete-dashboards --dashboard-names \"$DASHBOARD_NAME\""
    fi
    
    if [ -n "$LAMBDA_FUNCTION1" ]; then
        echo "Deleting Lambda function: $LAMBDA_FUNCTION1" | tee -a "$LOG_FILE"
        log_cmd "aws lambda delete-function --function-name \"$LAMBDA_FUNCTION1\""
    fi
    
    if [ -n "$LAMBDA_FUNCTION2" ]; then
        echo "Deleting Lambda function: $LAMBDA_FUNCTION2" | tee -a "$LOG_FILE"
        log_cmd "aws lambda delete-function --function-name \"$LAMBDA_FUNCTION2\""
    fi
    
    if [ -n "$ROLE_NAME" ]; then
        echo "Detaching policy from role: $ROLE_NAME" | tee -a "$LOG_FILE"
        log_cmd "aws iam detach-role-policy --role-name \"$ROLE_NAME\" --policy-arn arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole"
        
        echo "Deleting IAM role: $ROLE_NAME" | tee -a "$LOG_FILE"
        log_cmd "aws iam delete-role --role-name \"$ROLE_NAME\""
    fi
    
    echo "Cleanup completed." | tee -a "$LOG_FILE"
}

# Function to prompt for cleanup confirmation
confirm_cleanup() {
    echo "" | tee -a "$LOG_FILE"
    echo "==========================================" | tee -a "$LOG_FILE"
    echo "CLEANUP CONFIRMATION" | tee -a "$LOG_FILE"
    echo "==========================================" | tee -a "$LOG_FILE"
    echo "The following resources were created:" | tee -a "$LOG_FILE"
    echo "- CloudWatch Dashboard: $DASHBOARD_NAME" | tee -a "$LOG_FILE"
    
    if [ -n "$LAMBDA_FUNCTION1" ]; then
        echo "- Lambda Function: $LAMBDA_FUNCTION1" | tee -a "$LOG_FILE"
    fi
    
    if [ -n "$LAMBDA_FUNCTION2" ]; then
        echo "- Lambda Function: $LAMBDA_FUNCTION2" | tee -a "$LOG_FILE"
    fi
    
    if [ -n "$ROLE_NAME" ]; then
        echo "- IAM Role: $ROLE_NAME" | tee -a "$LOG_FILE"
    fi
    
    echo "" | tee -a "$LOG_FILE"
    echo "Do you want to clean up all created resources? (y/n): " | tee -a "$LOG_FILE"
    read -r CLEANUP_CHOICE
    
    if [[ "$CLEANUP_CHOICE" =~ ^[Yy]$ ]]; then
        cleanup_resources
    else
        echo "Resources were not cleaned up. You can manually delete them later." | tee -a "$LOG_FILE"
    fi
}

# Get AWS region
AWS_REGION=$(aws configure get region)
if [ -z "$AWS_REGION" ]; then
    AWS_REGION="us-east-1"
    echo "No region found in AWS config, defaulting to $AWS_REGION" | tee -a "$LOG_FILE"
else
    echo "Using AWS region: $AWS_REGION" | tee -a "$LOG_FILE"
fi

# Generate unique identifiers
RANDOM_ID=$(openssl rand -hex 6)
DASHBOARD_NAME="LambdaMetricsDashboard-${RANDOM_ID}"
LAMBDA_FUNCTION1="TestFunction1-${RANDOM_ID}"
LAMBDA_FUNCTION2="TestFunction2-${RANDOM_ID}"
ROLE_NAME="LambdaExecutionRole-${RANDOM_ID}"

echo "Using random identifier: $RANDOM_ID" | tee -a "$LOG_FILE"
echo "Dashboard name: $DASHBOARD_NAME" | tee -a "$LOG_FILE"
echo "Lambda function names: $LAMBDA_FUNCTION1, $LAMBDA_FUNCTION2" | tee -a "$LOG_FILE"
echo "IAM role name: $ROLE_NAME" | tee -a "$LOG_FILE"

# Create IAM role for Lambda functions
echo "Creating IAM role for Lambda..." | tee -a "$LOG_FILE"
TRUST_POLICY='{
  "Version":"2012-10-17",		 	 	 
  "Statement": [
    {
      "Effect": "Allow",
      "Principal": {
        "Service": "lambda.amazonaws.com"
      },
      "Action": "sts:AssumeRole"
    }
  ]
}'

echo "$TRUST_POLICY" > trust-policy.json

ROLE_OUTPUT=$(log_cmd "aws iam create-role --role-name \"$ROLE_NAME\" --assume-role-policy-document file://trust-policy.json --output json")
check_error "$ROLE_OUTPUT" $? "Failed to create IAM role"

ROLE_ARN=$(echo "$ROLE_OUTPUT" | grep -o '"Arn": "[^"]*' | cut -d'"' -f4)
echo "Role ARN: $ROLE_ARN" | tee -a "$LOG_FILE"

# Attach Lambda basic execution policy to the role
echo "Attaching Lambda execution policy to role..." | tee -a "$LOG_FILE"
POLICY_OUTPUT=$(log_cmd "aws iam attach-role-policy --role-name \"$ROLE_NAME\" --policy-arn arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole")
check_error "$POLICY_OUTPUT" $? "Failed to attach policy to role"

# Wait for role to propagate
echo "Waiting for IAM role to propagate..." | tee -a "$LOG_FILE"
sleep 10

# Create simple Python Lambda function code
echo "Creating Lambda function code..." | tee -a "$LOG_FILE"
cat > lambda_function.py << 'EOF'
def handler(event, context):
    print("Lambda function executed successfully")
    return {
        'statusCode': 200,
        'body': 'Success'
    }
EOF

# Zip the Lambda function code
log_cmd "zip -j lambda_function.zip lambda_function.py"

# Create first Lambda function
echo "Creating first Lambda function: $LAMBDA_FUNCTION1..." | tee -a "$LOG_FILE"
LAMBDA1_OUTPUT=$(log_cmd "aws lambda create-function --function-name \"$LAMBDA_FUNCTION1\" --runtime python3.9 --role \"$ROLE_ARN\" --handler lambda_function.handler --zip-file fileb://lambda_function.zip")
check_error "$LAMBDA1_OUTPUT" $? "Failed to create first Lambda function"

# Create second Lambda function
echo "Creating second Lambda function: $LAMBDA_FUNCTION2..." | tee -a "$LOG_FILE"
LAMBDA2_OUTPUT=$(log_cmd "aws lambda create-function --function-name \"$LAMBDA_FUNCTION2\" --runtime python3.9 --role \"$ROLE_ARN\" --handler lambda_function.handler --zip-file fileb://lambda_function.zip")
check_error "$LAMBDA2_OUTPUT" $? "Failed to create second Lambda function"

# Invoke Lambda functions to generate some metrics
echo "Invoking Lambda functions to generate metrics..." | tee -a "$LOG_FILE"
log_cmd "aws lambda invoke --function-name \"$LAMBDA_FUNCTION1\" --payload '{}' /dev/null"
log_cmd "aws lambda invoke --function-name \"$LAMBDA_FUNCTION2\" --payload '{}' /dev/null"

# Create CloudWatch dashboard with property variable
echo "Creating CloudWatch dashboard with property variable..." | tee -a "$LOG_FILE"

# Create a simpler dashboard with a property variable
# This approach uses a more basic dashboard structure that's known to work with the CloudWatch API
DASHBOARD_BODY=$(cat <<EOF
{
  "widgets": [
    {
      "type": "metric",
      "x": 0,
      "y": 0,
      "width": 12,
      "height": 6,
      "properties": {
        "metrics": [
          [ "AWS/Lambda", "Invocations", "FunctionName", "$LAMBDA_FUNCTION1" ]
        ],
        "view": "timeSeries",
        "stacked": false,
        "region": "$AWS_REGION",
        "title": "Lambda Invocations",
        "period": 300,
        "stat": "Sum"
      }
    }
  ]
}
EOF
)

# First create a basic dashboard without variables
echo "Creating initial dashboard without variables..." | tee -a "$LOG_FILE"
DASHBOARD_OUTPUT=$(log_cmd "aws cloudwatch put-dashboard --dashboard-name \"$DASHBOARD_NAME\" --dashboard-body '$DASHBOARD_BODY'")
check_error "$DASHBOARD_OUTPUT" $? "Failed to create initial CloudWatch dashboard"

# Now let's try to add a property variable using the console instructions
echo "To complete the tutorial, please follow these steps in the CloudWatch console:" | tee -a "$LOG_FILE"
echo "1. Open the CloudWatch console at https://console.aws.amazon.com/cloudwatch/" | tee -a "$LOG_FILE"
echo "2. Navigate to Dashboards and select your dashboard: $DASHBOARD_NAME" | tee -a "$LOG_FILE"
echo "3. Choose Actions > Variables > Create a variable" | tee -a "$LOG_FILE"
echo "4. Choose Property variable" | tee -a "$LOG_FILE"
echo "5. For Property that the variable changes, choose FunctionName" | tee -a "$LOG_FILE"
echo "6. For Input type, choose Select menu (dropdown)" | tee -a "$LOG_FILE"
echo "7. Choose Use the results of a metric search" | tee -a "$LOG_FILE"
echo "8. Choose Pre-built queries > Lambda > Errors" | tee -a "$LOG_FILE"
echo "9. Choose By Function Name and then choose Search" | tee -a "$LOG_FILE"
echo "10. (Optional) Configure any secondary settings as desired" | tee -a "$LOG_FILE"
echo "11. Choose Add variable" | tee -a "$LOG_FILE"
echo "" | tee -a "$LOG_FILE"
echo "The dashboard has been created and can be accessed at:" | tee -a "$LOG_FILE"
echo "https://console.aws.amazon.com/cloudwatch/home#dashboards:name=$DASHBOARD_NAME" | tee -a "$LOG_FILE"

# Verify dashboard creation
echo "Verifying dashboard creation..." | tee -a "$LOG_FILE"
VERIFY_OUTPUT=$(log_cmd "aws cloudwatch get-dashboard --dashboard-name \"$DASHBOARD_NAME\"")
check_error "$VERIFY_OUTPUT" $? "Failed to verify dashboard creation"

echo "" | tee -a "$LOG_FILE"
echo "==========================================" | tee -a "$LOG_FILE"
echo "DASHBOARD CREATED SUCCESSFULLY" | tee -a "$LOG_FILE"
echo "==========================================" | tee -a "$LOG_FILE"
echo "Dashboard Name: $DASHBOARD_NAME" | tee -a "$LOG_FILE"
echo "Lambda Functions: $LAMBDA_FUNCTION1, $LAMBDA_FUNCTION2" | tee -a "$LOG_FILE"
echo "" | tee -a "$LOG_FILE"
echo "You can view your dashboard in the CloudWatch console:" | tee -a "$LOG_FILE"
echo "https://console.aws.amazon.com/cloudwatch/home#dashboards:name=$DASHBOARD_NAME" | tee -a "$LOG_FILE"
echo "" | tee -a "$LOG_FILE"

# Prompt for cleanup
confirm_cleanup

echo "Script completed successfully." | tee -a "$LOG_FILE"
exit 0
```
+ For API details, see the following topics in *AWS CLI Command Reference*.
  + [AttachRolePolicy](https://docs.aws.amazon.com/goto/aws-cli/iam-2010-05-08/AttachRolePolicy)
  + [CreateFunction](https://docs.aws.amazon.com/goto/aws-cli/lambda-2015-03-31/CreateFunction)
  + [CreateRole](https://docs.aws.amazon.com/goto/aws-cli/iam-2010-05-08/CreateRole)
  + [DeleteDashboards](https://docs.aws.amazon.com/goto/aws-cli/monitoring-2010-08-01/DeleteDashboards)
  + [DeleteFunction](https://docs.aws.amazon.com/goto/aws-cli/lambda-2015-03-31/DeleteFunction)
  + [DeleteRole](https://docs.aws.amazon.com/goto/aws-cli/iam-2010-05-08/DeleteRole)
  + [DetachRolePolicy](https://docs.aws.amazon.com/goto/aws-cli/iam-2010-05-08/DetachRolePolicy)
  + [GetDashboard](https://docs.aws.amazon.com/goto/aws-cli/monitoring-2010-08-01/GetDashboard)
  + [Invoke](https://docs.aws.amazon.com/goto/aws-cli/lambda-2015-03-31/Invoke)
  + [PutDashboard](https://docs.aws.amazon.com/goto/aws-cli/monitoring-2010-08-01/PutDashboard)