API网关-主体映射模板-可选主体参数

问题描述

我有一个POST API网关方法，我将向其中发送以下application/json主体，以将参数从其传递到该方法所连接的Lambda:

I have a POST API Gateway method to which I am sending the following application/json body in order to pass parameters from it to a Lambda that the method is connected to:

{
    "otherClientId": "12345",
    "message": "Text",
    "seconds": 0,
    "hours": 0
}

我正在使用以下映射模板:

I am using the following mapping template:

#set($inputRoot = $input.path('$'))
{
  "authorizedUser": "$context.authorizer.principalId",
  "otherClientId": "$inputRoot.otherClientId",
  "message": "$inputRoot.message",
  "amount": $inputRoot.amount,
  "duration": $inputRoot.duration
}

我遇到的问题是，尝试发送没有数量或持续时间的请求时收到错误字符串"错误.由于某些原因，这些参数似乎不是可选的(但我需要将它们设为！).我能够错过其他参数，例如message，但是不能错过两个数字参数.

The problem I am experiencing is that I receive a "Bad String" error when attempting to send the request without amount or duration. For some reason these parameters do not seem to be optional (but I need them to be!).I am able to miss out other parameters, like message for instance, but not the two number parameters.

是否有人经历过这种情况，或者有人可以指出我很可能会失踪的明显现象?AWS文档对此主题很少.

Has anybody else experienced this or can somebody point out the obvious that I am probably missing? The AWS documentation is a little sparse on the subject.

推荐答案

可能是因为没有传递这些参数，您的json请求看起来像这样:

Probably, this is happening because without passing those params, your json request looks like:

#set($inputRoot = $input.path('$'))
{
  "authorizedUser": "$context.authorizer.principalId",
  "otherClientId": "$inputRoot.otherClientId",
  "message": "$inputRoot.message",
  "amount": ,
  "duration":
}

最简单的解决方法是用引号将 $ inputRoot.amount 和 $ inputRoot.duration 包裹起来:

The simplest way to fix is to wrap $inputRoot.amount and $inputRoot.duration with quotes:

#set($inputRoot = $input.path('$'))
{
   "authorizedUser": "$context.authorizer.principalId",
   "otherClientId": "$inputRoot.otherClientId",
   "message": "$inputRoot.message",
   "amount": "$inputRoot.amount",
   "duration": "$inputRoot.duration"
}

或者，您可以使用if条件连接请求，例如:

Alternatively, you can concatenate request using if condition for example:

#set($hasLimit = $input.params('limit') != "")
#set($hasOffset = $input.params('offset') != "")
#set($hasPeriod = $input.params('period') != "")
#set($hasType = $input.params('type') != "")
{
    "environment": "$input.params('environment')"
    #if($hasLimit),"limit": $input.params('limit')#end
    #if($hasOffset),"offset": $input.params('offset')#end
    #if($hasPeriod),"period": "$input.params('period')"#end
    #if($hasType),"type": "$input.params('type')"#end
}

这篇关于API网关-主体映射模板-可选主体参数的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！