Network.Wai.Handler.Lambda

Documentation

type RawResponse = (Status, ResponseHeaders, ByteString)

data Settings

Constructors

Settings

Fields

• timeoutValue :: Int
• handleTimeout :: ByteString -> IO RawResponse
• handleException :: ByteString -> SomeException -> IO RawResponse

run :: Application -> IO ()

Run an Application.

Continuously reads requests from stdin. Each line should be a a JSON document as described in decodeInput.

All requests will be timed out after 2 seconds. If any exception is thrown while processing the request this will return an HTTP 500 Internal Server Error.

If you need more control use handleRequest directly.

runSettings :: Settings -> Application -> IO ()

setTimeoutSeconds :: Int -> Settings -> Settings

setHandleException :: (ByteString -> SomeException -> IO RawResponse) -> Settings -> Settings

setHandleTimeout :: (ByteString -> IO RawResponse) -> Settings -> Settings

defaultSettings :: Settings

defaultHandleException :: ByteString -> SomeException -> IO RawResponse

defaultTimeoutValue :: Int

Default request timeout. 2 seconds.

defaultHandleTimeout :: ByteString -> IO RawResponse

handleRequest

Arguments

:: Settings

-> Application

-> ByteString

The request (see decodeInput)

-> IO ()

Parse and handle the request.

• Returns 504 if no response is available after the specified timeout.
• Returns 500 if an exception occurs while processing the request.
• Throws an exception if the input cannot be parsed.

processRequest :: Application -> Request -> IO Response

Run the Request through the Application.

This function is completely dependent on the 'Application. Any exception thrown by the Application will be rethrown here. No timeout is implemented: if the Application never provides a Response then processRequest won't return.

decodeInput :: ByteString -> Either (JSONPath, String) (FilePath, IO Request)

Decode a ByteString into (1) a Wai Request and (2) a filepath where the response should be written. The argument is JSON document with two fields: * request: the API Gateway request (see parseRequest) * reqsponseFile: Where to write the API Gateway response (see toJSONResponse)

parseRequest :: Value -> Parser (IO Request)

Parser for a Request.

The input is an AWS API Gateway request event: https://docs.aws.amazon.com/lambda/latest/dg/eventsources.html#eventsources-api-gateway-request

originalRequestKey :: Key Object

readResponse :: Response -> IO RawResponse

Read the status, headers and body of a Response.

toJSONResponse :: Status -> ResponseHeaders -> ByteString -> Object

Make an API Gateway response from status, headers and body. https://docs.aws.amazon.com/lambda/latest/dg/eventsources.html#eventsources-api-gateway-response

writeFileAtomic :: FilePath -> ByteString -> IO ()

Atomically write the ByteString to the file.

Uses rename(2).

xif :: b -> ((b -> c) -> b -> c) -> c

flip fix

uncurry3 :: (a -> b -> c -> d) -> (a, b, c) -> d