Type alias FunctionHandler

Type declaration

• [brandSymbol]: typeof functionHandlerBrand

• [dataSymbol]: FunctionHandlerData

• async:function

  • async(): AsyncFunctionHandler

  • Use async() to have this function handler invoked asynchronously. If an async() function is only handler or the final handler in a pipeline, the return type of this custom query / mutation is { success: boolean }.

    Returns AsyncFunctionHandler

    A function handler for query / mutation that is asynchronously invoked.

    Example

    import {
      type ClientSchema,
      a,
      defineData,
      defineFunction // 1.Import "defineFunction" to create new functions
    } from '@aws-amplify/backend';
    
    // 2. define a function
    const echoHandler = defineFunction({
      entry: './echo-handler/handler.ts'
    })
    
    const schema = a.schema({
      EchoResponse: a.customType({
        content: a.string(),
        executionDuration: a.float()
      }),
    
      echo: a
        .query()
        .arguments({ content: a.string() })
        .returns(a.ref('EchoResponse'))
        .authorization(allow => [allow.publicApiKey()])
        // 3. set the function has the handler
        .handler(a.handler.function(echoHandler).async())
    Copy

    See

    https://docs.amplify.aws/react/build-a-backend/data/custom-business-logic/#async-function-handlers