golambda

README

Go goodies for AWS Lambda

The main features of this module are the various wrappers around different AWS Lambda events, for example:

• Lambda Function URL, supporting both BUFFERED and RESPONSE_STREAM modes.
• API Gateway HTTP Integration with custom authoriser wrapper.
• DynamoDB Stream and other events.

Other utilities:

• Must provides Must, Must0, Must2, etc. to reduce typing out if a, err := someFunction(); err != nil.
• DynamoDB needs such as modeling version attribute, timestamps, utilities around making GetItem, PutItem, UpdateItem, and DeleteItem requests.
• Metrics measures arbitrary counters, timings, properties, and produce a JSON message describing about those metrics.
• Parse or log Smithy errors.

The module is very opinionated about how things are done because they work for me, but I'm always looking for feedback and suggestions.

Getting Started

The root module exposes a generic wrapper that attaches a metrics instance to the context:

# Download build.py to make it easier to build and update Lambda functions.
curl --proto '=https' -fo build.py https://raw.githubusercontent.com/nguyengg/golambda/main/build.py

package main

import (
	"context"

	"github.com/aws/aws-lambda-go/events"
	"github.com/nguyengg/golambda"
	"github.com/nguyengg/golambda/logsupport"
)

func main() {
	golambda.StartHandlerFunc(func(ctx context.Context, request events.LambdaFunctionURLRequest) (events.LambdaFunctionURLResponse, error) {
		// will set LambdaContext.AwsRequestID to log prefix and reset upon completion.
		defer logsupport.SetUpGlobalLogger(ctx)()

		return events.LambdaFunctionURLResponse{
			StatusCode: 200,
			Body:       "hello, world!",
		}, nil
	})
}

Documentation

Index

• func StartHandlerFunc[TIn any, TOut any, H lambda.HandlerFunc[TIn, TOut]](handler H, options ...start.Option)

Functions

func StartHandlerFunc

func StartHandlerFunc[TIn any, TOut any, H lambda.HandlerFunc[TIn, TOut]](handler H, options ...start.Option)

StartHandlerFunc calls lambda.StartHandlerFunc passing the given handler after wrapping the context with a metrics instance that is used to populate basis statistics about the invocation.

Use this wrapper if there isn't one created for specific events.