Library to help Go developers handle multiple types of events (de-multiplexing) in AWS Lambda functions.
The primary function of this library is to create events of a specific type and dispatch those to appropriate handlers.
To do so the demuxer is configured with Factory
and Handler
instances.
Factories are responsible for determining the type of the event (based off the incoming JSON) and creating an instance of that event.
Handlers are responsible for, well, handling that event. Handlers are as used in aws-lambda-go , with the restriction
of having a signature of func(context.Context, *eventType) (*responseType, error)
. eventType
and responseType
can be any struct with the appropriate json tags to map from the event JSON.
A minimal usage showing a lambda that handles REST API request and Websocket lifecycle events:
// main.go
package main
import (
"github.com/aws/aws-lambda-go/lambda"
"github.com/cloudshiftinc/aws-lambda-demux/demux"
)
func main() {
cfg := &demux.Cfg{
Factories: []demux.Factory{
func(ctx *demux.EventContext) any {
if demux.HasAttribute(ctx.Event, "connectionId") {
return &events.APIGatewayWebsocketProxyRequest{}
}
return &events.APIGatewayProxyRequest{}
},
},
Handlers: []any{
func(ctx context.Context, event *events.APIGatewayWebsocketProxyRequest) (
*events.APIGatewayProxyResponse, error) {
// TODO - your code here to handle websocket event
return &events.APIGatewayProxyResponse{}, nil
},
func(ctx context.Context, event *events.APIGatewayProxyRequest) (
*events.APIGatewayProxyResponse,
error) {
// TODO - your code here to handle HTTP/REST event
return &events.APIGatewayProxyResponse{}, nil
},
},
}
lambda.Start(demux.NewHandler(cfg))
}
This library is not limited to event types in aws-lambda-go; any event type (including your own custom ones) that as appropriate JSON mappings can be used.