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AWS code-library documentation change

Service: code-library · 2026-05-01 · Documentation low

File: code-library/latest/ug/lambda_example_lambda_GettingStarted_019_section.md

Summary

Enhanced script robustness with error handling, input validation, and security improvements in Lambda function code

Security assessment

Changes focus on improving input validation and error handling in Lambda functions (Python/Node.js) to reject invalid/malformed inputs, but don't reference any specific CVE or security incident. Added input sanitization and resource cleanup reduce potential error conditions but aren't explicitly security fixes.

Diff

diff --git a/code-library/latest/ug/lambda_example_lambda_GettingStarted_019_section.md b/code-library/latest/ug/lambda_example_lambda_GettingStarted_019_section.md
index 70ae7187a..142d0f63c 100644
--- a//code-library/latest/ug/lambda_example_lambda_GettingStarted_019_section.md
+++ b//code-library/latest/ug/lambda_example_lambda_GettingStarted_019_section.md
@@ -49 +49 @@ There's more on GitHub. Find the complete example and learn how to set up and ru
-    set -eE
+    set -eE -o pipefail
@@ -55 +55 @@ There's more on GitHub. Find the complete example and learn how to set up and ru
-    UNIQUE_ID=$(cat /dev/urandom | tr -dc 'a-z0-9' | fold -w 8 | head -n 1)
+    UNIQUE_ID=$(head -c 8 /dev/urandom | od -An -tx1 | tr -d ' ')
@@ -60,0 +61 @@ There's more on GitHub. Find the complete example and learn how to set up and ru
+    readonly TEMP_DIR
@@ -169,0 +171,10 @@ There's more on GitHub. Find the complete example and learn how to set up and ru
+    validate_input() {
+        local input="$1"
+        local pattern="$2"
+        if ! [[ "$input" =~ $pattern ]]; then
+            echo "ERROR: Invalid input: $input"
+            return 1
+        fi
+        return 0
+    }
+    
@@ -194,2 +205,2 @@ There's more on GitHub. Find the complete example and learn how to set up and ru
-    echo "Enter your choice (1 or 2): "
-    read -r RUNTIME_CHOICE
+    echo "Using default: Python 3.13"
+    RUNTIME_CHOICE="1"
@@ -208,2 +219,7 @@ There's more on GitHub. Find the complete example and learn how to set up and ru
-        length = event['length']
-        width = event['width']
+        if not isinstance(event, dict) or 'length' not in event or 'width' not in event:
+            raise ValueError('Event must contain length and width')
+        try:
+            length = float(event['length'])
+            width = float(event['width'])
+            if length < 0 or width < 0:
+                raise ValueError('Length and width must be non-negative')
@@ -213,0 +230,3 @@ There's more on GitHub. Find the complete example and learn how to set up and ru
+        except (TypeError, ValueError) as e:
+            logger.error(f'Error processing input: {str(e)}')
+            raise
@@ -224,0 +244,6 @@ There's more on GitHub. Find the complete example and learn how to set up and ru
+      if (!event || typeof event.length !== 'number' || typeof event.width !== 'number') {
+        throw new Error('Event must contain numeric length and width');
+      }
+      if (event.length < 0 || event.width < 0) {
+        throw new Error('Length and width must be non-negative');
+      }
@@ -267,0 +293,6 @@ There's more on GitHub. Find the complete example and learn how to set up and ru
+    
+    if ! validate_input "$ROLE_OUTPUT" "^arn:aws:iam::[0-9]+:role/"; then
+        echo "ERROR: Failed to create IAM role"
+        exit 1
+    fi
+    
@@ -297,3 +328,11 @@ There's more on GitHub. Find the complete example and learn how to set up and ru
-    cd "$TEMP_DIR"
-    zip -j function.zip "$CODE_FILE" > /dev/null 2>&1
-    cd "$ORIGINAL_DIR"
+    cd "$TEMP_DIR" || exit 1
+    zip -j function.zip "$CODE_FILE" > /dev/null 2>&1 || {
+        echo "ERROR: Failed to create deployment package"
+        exit 1
+    }
+    cd "$ORIGINAL_DIR" || exit 1
+    
+    if [ ! -f "${TEMP_DIR}/function.zip" ]; then
+        echo "ERROR: Deployment package creation failed"
+        exit 1
+    fi
@@ -314,0 +354,6 @@ There's more on GitHub. Find the complete example and learn how to set up and ru
+    
+    if [ -z "$CREATE_OUTPUT" ]; then
+        echo "ERROR: Failed to create Lambda function"
+        exit 1
+    fi
+    
@@ -337,0 +383,5 @@ There's more on GitHub. Find the complete example and learn how to set up and ru
+    if ! validate_input "$TEST_EVENT" '"length": [0-9]+, "width": [0-9]+'; then
+        echo "ERROR: Invalid test event format"
+        exit 1
+    fi
+    
@@ -344,0 +395,5 @@ There's more on GitHub. Find the complete example and learn how to set up and ru
+    if [ ! -f "${TEMP_DIR}/response.json" ]; then
+        echo "ERROR: No response file generated"
+        exit 1
+    fi
+    
@@ -418 +473 @@ There's more on GitHub. Find the complete example and learn how to set up and ru
-    echo "CLEANUP CONFIRMATION"
+    echo "CLEANUP"
@@ -421,4 +476 @@ There's more on GitHub. Find the complete example and learn how to set up and ru
-    echo "Do you want to clean up all created resources? (y/n): "
-    read -r CLEANUP_CHOICE
-    
-    if [[ "$CLEANUP_CHOICE" =~ ^[Yy]$ ]]; then
+    echo "Cleaning up all created resources..."
@@ -426,19 +477,0 @@ There's more on GitHub. Find the complete example and learn how to set up and ru
-    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