lambda

README

Overview

Documentation

Index

• func Start(handler interface{})
• func StartHandler(handler Handler)
• type Function
  • func (fn *Function) Invoke(req *messages.InvokeRequest, response *messages.InvokeResponse) error
  • func (fn *Function) Ping(req *messages.PingRequest, response *messages.PingResponse) error
• type Handler
  • func NewHandler(handlerFunc interface{}) Handler

Functions

func Start

func Start(handler interface{})

Start takes a handler and talks to an internal Lambda endpoint to pass requests to the handler. If the handler does not match one of the supported types an appropriate error message will be returned to the caller. Start blocks, and does not return after being called.

Rules:

• handler must be a function
• handler may take between 0 and two arguments.
• if there are two arguments, the first argument must satisfy the "context.Context" interface.
• handler may return between 0 and two arguments.
• if there are two return values, the second argument must be an error.
• if there is one return value it must be an error.

Valid function signatures:

func ()
func () error
func (TIn) error
func () (TOut, error)
func (TIn) (TOut, error)
func (context.Context) error
func (context.Context, TIn) error
func (context.Context) (TOut, error)
func (context.Context, TIn) (TOut, error)

Where "TIn" and "TOut" are types compatible with the "encoding/json" standard library. See https://golang.org/pkg/encoding/json/#Unmarshal for how deserialization behaves

func StartHandler

func StartHandler(handler Handler)

StartHandler takes in a Handler wrapper interface which can be implemented either by a custom function or a struct.

Handler implementation requires a single "Invoke()" function:

func Invoke(context.Context, []byte) ([]byte, error)

Types

type Function

type Function struct {
	// contains filtered or unexported fields
}

func (*Function) Invoke

func (fn *Function) Invoke(req *messages.InvokeRequest, response *messages.InvokeResponse) error

func (*Function) Ping

func (fn *Function) Ping(req *messages.PingRequest, response *messages.PingResponse) error

type Handler

type Handler interface {
	Invoke(ctx context.Context, payload []byte) ([]byte, error)
}

func NewHandler

func NewHandler(handlerFunc interface{}) Handler

NewHandler creates a base lambda handler from the given handler function. The returned Handler performs JSON deserialization and deserialization, and delegates to the input handler function. The handler function parameter must satisfy the rules documented by Start. If handlerFunc is not a valid handler, the returned Handler simply reports the validation error.