AWS API网关默认限制输入/输出负载大小为10MB。但是，如果您的API负载超过API网关的限制，则API网关将拒绝该请求。要解决这个问题，可以通过在API Gateway设置中修改负载大小限制来扩展它。

以下是一个示例，将API Gateway负载限制增加到50MB：

Resources:
  MyResource:
    Type: AWS::ApiGateway::Resource
    Properties:
      ParentId: !GetAtt ApiGateway.RestApiRootResourceId
      PathPart: myresource

  MyMethod:
    Type: AWS::ApiGateway::Method
    Properties:
      HttpMethod: POST
      ResourceId: !Ref MyResource
      RestApiId: !Ref ApiGateway
      AuthorizationType: NONE
      Integration:
        Type: AWS_PROXY
        IntegrationHttpMethod: POST
        Uri: !Sub
            - "https://${MyLambdaFunction.Arn}/"
            - { MyLambdaFunction: !Ref MyLambdaFunction }
        PassthroughBehavior: WHEN_NO_MATCH
        ContentHandling: CONVERT_TO_BINARY
        RequestParameters:
          integration.request.header.Content-Type: "'application/json'"
        RequestTemplates:
          application/json: !Ref RequestTemplate
      MethodResponses:
        - StatusCode: 200
          ResponseModels:
            application/json: "Empty"

  ApiGateway:
    Type: AWS::ApiGateway::RestApi
    Properties:
      Name: "My API"
      BinaryMediaTypes:
        - 'application/octet-stream'
        - 'image/jpeg'
      EndpointConfiguration:
        Types:
          - "EDGE"
      Policy: !Join
          - "\n"
          - - "Version: '2012-10-17'"
            - "Statement:"
            - "  - Effect: Allow"
            - "    Principal: '*'"
            - "    Action:"
            - "      - execute-api:Invoke"
            - "    Resource:"
            - "      - !Sub 'arn:aws:execute-api:${AWS::Region}:${AWS::AccountId}:${ApiGateway}/test/POST/myresource/*'"
  Stage:
    Type: AWS::ApiGateway::Stage
    Properties: