AWS Lambda worker

Abstract AWS Lambda worker process

The github.com/go-nacelle/lambdabase package provides an abstract AWS Lambda worker process.

This library supplies an abstract AWS Lambda RPC server process whose behavior can be be configured by implementing a Handler interface. This interface wraps the handler defined by aws-lambda-go.

A Lambda server process is created by supplying a handler, described below, that controls its behavior.

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server := lambdabase.NewServer(NewHandler(), options...)

A handler is a struct with an Init and a Handle method. The initialization method, like the process that runs it, that takes a context as a parameter adn returns an error value. The handle method of the base server takes a context object and the request payload as parameters and returns the response payload and an error value. The handle method of an event-specific server takes a context object, the request payload, and a logger populated with request and event identifiers as parameters and returns an error value. Return an error from either method signals a fatal error to the process that runs it.

The following example implements a handler that transforms a request value to upper-case.

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type Handler struct {}

type ReqResp struct {
    Value string `json:"text"`
}

func (h *Handler) Init(ctx context.Context) error {
    return nil
}

func (h *Handler) (ctx context.Context, payload []byte) ([]byte, error) {
    request := &ReqResp{}
    if err := json.Unmarshal(payload, &request); err != nil {
        return nil, err
    }

    return json.Marshal(&ReqResp{Value: strings.ToUpper(request.Value)})
}

This library comes with an example project that logs values received from a Kinesis stream.

Abstract AWS Lambda worker process

Related resources