Hello Lambda - AWS SDK Code Examples

There are more AWS SDK examples available in the AWS Doc SDK Examples GitHub repo.

Hello Lambda

The following code examples show how to get started using Lambda.

.NET
AWS SDK for .NET
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the AWS Code Examples Repository.

namespace LambdaActions; using Amazon.Lambda; public class HelloLambda { static async Task Main(string[] args) { var lambdaClient = new AmazonLambdaClient(); Console.WriteLine("Hello AWS Lambda"); Console.WriteLine("Let's get started with AWS Lambda by listing your existing Lambda functions:"); var response = await lambdaClient.ListFunctionsAsync(); response.Functions.ForEach(function => { Console.WriteLine($"{function.FunctionName}\t{function.Description}"); }); } }
  • For API details, see ListFunctions in AWS SDK for .NET API Reference.

C++
SDK for C++
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the AWS Code Examples Repository.

Code for the CMakeLists.txt CMake file.

# Set the minimum required version of CMake for this project. cmake_minimum_required(VERSION 3.13) # Set the AWS service components used by this project. set(SERVICE_COMPONENTS lambda) # Set this project's name. project("hello_lambda") # Set the C++ standard to use to build this target. # At least C++ 11 is required for the AWS SDK for C++. set(CMAKE_CXX_STANDARD 11) # Use the MSVC variable to determine if this is a Windows build. set(WINDOWS_BUILD ${MSVC}) if (WINDOWS_BUILD) # Set the location where CMake can find the installed libraries for the AWS SDK. string(REPLACE ";" "/aws-cpp-sdk-all;" SYSTEM_MODULE_PATH "${CMAKE_SYSTEM_PREFIX_PATH}/aws-cpp-sdk-all") list(APPEND CMAKE_PREFIX_PATH ${SYSTEM_MODULE_PATH}) endif () # Find the AWS SDK for C++ package. find_package(AWSSDK REQUIRED COMPONENTS ${SERVICE_COMPONENTS}) if (WINDOWS_BUILD AND AWSSDK_INSTALL_AS_SHARED_LIBS) # Copy relevant AWS SDK for C++ libraries into the current binary directory for running and debugging. # set(BIN_SUB_DIR "/Debug") # if you are building from the command line you may need to uncomment this # and set the proper subdirectory to the executables' location. AWSSDK_CPY_DYN_LIBS(SERVICE_COMPONENTS "" ${CMAKE_CURRENT_BINARY_DIR}${BIN_SUB_DIR}) endif () add_executable(${PROJECT_NAME} hello_lambda.cpp) target_link_libraries(${PROJECT_NAME} ${AWSSDK_LINK_LIBRARIES})

Code for the hello_lambda.cpp source file.

#include <aws/core/Aws.h> #include <aws/lambda/LambdaClient.h> #include <aws/lambda/model/ListFunctionsRequest.h> #include <iostream> /* * A "Hello Lambda" starter application which initializes an AWS Lambda (Lambda) client and lists the Lambda functions. * * main function * * Usage: 'hello_lambda' * */ int main(int argc, char **argv) { Aws::SDKOptions options; // Optionally change the log level for debugging. // options.loggingOptions.logLevel = Utils::Logging::LogLevel::Debug; Aws::InitAPI(options); // Should only be called once. int result = 0; { Aws::Client::ClientConfiguration clientConfig; // Optional: Set to the AWS Region (overrides config file). // clientConfig.region = "us-east-1"; Aws::Lambda::LambdaClient lambdaClient(clientConfig); std::vector<Aws::String> functions; Aws::String marker; // Used for pagination. do { Aws::Lambda::Model::ListFunctionsRequest request; if (!marker.empty()) { request.SetMarker(marker); } Aws::Lambda::Model::ListFunctionsOutcome outcome = lambdaClient.ListFunctions( request); if (outcome.IsSuccess()) { const Aws::Lambda::Model::ListFunctionsResult &listFunctionsResult = outcome.GetResult(); std::cout << listFunctionsResult.GetFunctions().size() << " lambda functions were retrieved." << std::endl; for (const Aws::Lambda::Model::FunctionConfiguration &functionConfiguration: listFunctionsResult.GetFunctions()) { functions.push_back(functionConfiguration.GetFunctionName()); std::cout << functions.size() << " " << functionConfiguration.GetDescription() << std::endl; std::cout << " " << Aws::Lambda::Model::RuntimeMapper::GetNameForRuntime( functionConfiguration.GetRuntime()) << ": " << functionConfiguration.GetHandler() << std::endl; } marker = listFunctionsResult.GetNextMarker(); } else { std::cerr << "Error with Lambda::ListFunctions. " << outcome.GetError().GetMessage() << std::endl; result = 1; break; } } while (!marker.empty()); } Aws::ShutdownAPI(options); // Should only be called once. return result; }
  • For API details, see ListFunctions in AWS SDK for C++ API Reference.

Go
SDK for Go V2
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the AWS Code Examples Repository.

package main import ( "context" "fmt" "github.com/aws/aws-sdk-go-v2/aws" "github.com/aws/aws-sdk-go-v2/config" "github.com/aws/aws-sdk-go-v2/service/lambda" ) // main uses the AWS SDK for Go (v2) to create an AWS Lambda client and list up to 10 // functions in your account. // This example uses the default settings specified in your shared credentials // and config files. func main() { ctx := context.Background() sdkConfig, err := config.LoadDefaultConfig(ctx) if err != nil { fmt.Println("Couldn't load default configuration. Have you set up your AWS account?") fmt.Println(err) return } lambdaClient := lambda.NewFromConfig(sdkConfig) maxItems := 10 fmt.Printf("Let's list up to %v functions for your account.\n", maxItems) result, err := lambdaClient.ListFunctions(ctx, &lambda.ListFunctionsInput{ MaxItems: aws.Int32(int32(maxItems)), }) if err != nil { fmt.Printf("Couldn't list functions for your account. Here's why: %v\n", err) return } if len(result.Functions) == 0 { fmt.Println("You don't have any functions!") } else { for _, function := range result.Functions { fmt.Printf("\t%v\n", *function.FunctionName) } } }
  • For API details, see ListFunctions in AWS SDK for Go API Reference.

Java
SDK for Java 2.x
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the AWS Code Examples Repository.

/** * Lists the AWS Lambda functions associated with the current AWS account. * * @param awsLambda an instance of the {@link LambdaClient} class, which is used to interact with the AWS Lambda service * * @throws LambdaException if an error occurs while interacting with the AWS Lambda service */ public static void listFunctions(LambdaClient awsLambda) { try { ListFunctionsResponse functionResult = awsLambda.listFunctions(); List<FunctionConfiguration> list = functionResult.functions(); for (FunctionConfiguration config : list) { System.out.println("The function name is " + config.functionName()); } } catch (LambdaException e) { System.err.println(e.getMessage()); System.exit(1); } }
  • For API details, see ListFunctions in AWS SDK for Java 2.x API Reference.

JavaScript
SDK for JavaScript (v3)
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the AWS Code Examples Repository.

import { LambdaClient, paginateListFunctions } from "@aws-sdk/client-lambda"; const client = new LambdaClient({}); export const helloLambda = async () => { const paginator = paginateListFunctions({ client }, {}); const functions = []; for await (const page of paginator) { const funcNames = page.Functions.map((f) => f.FunctionName); functions.push(...funcNames); } console.log("Functions:"); console.log(functions.join("\n")); return functions; };
  • For API details, see ListFunctions in AWS SDK for JavaScript API Reference.

Python
SDK for Python (Boto3)
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the AWS Code Examples Repository.

import boto3 def main(): """ List the Lambda functions in your AWS account. """ # Create the Lambda client lambda_client = boto3.client("lambda") # Use the paginator to list the functions paginator = lambda_client.get_paginator("list_functions") response_iterator = paginator.paginate() print("Here are the Lambda functions in your account:") for page in response_iterator: for function in page["Functions"]: print(f" {function['FunctionName']}") if __name__ == "__main__": main()
  • For API details, see ListFunctions in AWS SDK for Python (Boto3) API Reference.

Ruby
SDK for Ruby
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the AWS Code Examples Repository.

require 'aws-sdk-lambda' # Creates an AWS Lambda client using the default credentials and configuration def lambda_client Aws::Lambda::Client.new end # Lists the Lambda functions in your AWS account, paginating the results if necessary def list_lambda_functions lambda = lambda_client # Use a pagination iterator to list all functions functions = [] lambda.list_functions.each_page do |page| functions.concat(page.functions) end # Print the name and ARN of each function functions.each do |function| puts "Function name: #{function.function_name}" puts "Function ARN: #{function.function_arn}" puts end puts "Total functions: #{functions.count}" end list_lambda_functions if __FILE__ == $PROGRAM_NAME
  • For API details, see ListFunctions in AWS SDK for Ruby API Reference.