我有一个如下所示的请求:
package pricing
import scala.beans.BeanProperty
class Request(@BeanProperty var name: String, @BeanProperty var surname: String) {
def this() = this(name="defName", surname="defSurname")
}
处理程序如下:
package pricing
import com.amazonaws.services.lambda.runtime.{Context, RequestHandler}
import scala.collection.JavaConverters
import spray.json._
class ApiGatewayHandler extends RequestHandler[Request, ApiGatewayResponse] {
import DefaultJsonProtocol._
def handleRequest(input: Request, context: Context): ApiGatewayResponse = {
val headers = Map("x-foo" -> "coucou")
val msg = "Hello " + input.name
val message = Map[String, String]("message" -> msg )
ApiGatewayResponse(
200,
message.toJson.toString(),
JavaConverters.mapAsJavaMap[String, Object](headers),
true
)
}
}
已记录为:
functions:
pricing:
handler: pricing.ApiGatewayHandler
events:
- http:
path: pricing/test
method: get
documentation:
summary: "submit your name and surname, the API says hi"
description: ".. well, the summary is pretty exhaustive"
requestBody:
description: "Send over name and surname"
queryParams:
- name: "name"
description: "your 1st name"
- name: "surname"
description: ".. guess .. "
methodResponses:
- statusCode: "200"
responseHeaders:
- name: "x-foo"
description: "you can foo in here"
responseBody:
description: "You'll see a funny message here"
responseModels:
"application/json": "HelloWorldResponse"
好吧,这是其中一个教程的复制和粘贴。它不起作用。
我猜 BeanProperty
指的是 body 对象属性;这是我可以从示例中猜到的 here
.
如果我想要查询字符串?
尝试是:
package pricing
import scala.beans.BeanProperty
import spray.json._
abstract class ApiGatewayGetRequest(
@BeanProperty httpMethod: String,
@BeanProperty headers: Map[String, String],
@BeanProperty queryStringParameters: Map[String, String])
abstract class ApiGatewayPostRequest(
@BeanProperty httpMethod: String,
@BeanProperty headers: Map[String, String],
@BeanProperty queryStringParameters: Map[String, String])
class HelloWorldRequest(
@BeanProperty httpMethod: String,
@BeanProperty headers: Map[String, String],
@BeanProperty queryStringParameters: Map[String, String]
) extends ApiGatewayGetRequest(httpMethod, headers, queryStringParameters) {
private def getParam(param: String): String =
queryStringParameters get param match {
case Some(s) => s
case None => "default_" + param
}
def name: String = getParam("name")
def surname: String = getParam("surname")
def this() = this("GET", Map.empty, Map.empty)
}
结果是:
{
"message":"Hello default_name"
}
建议该类已用空映射代替 queryStringParameters
进行了初始化,但已正确提交
Mon Sep 25 20:45:22 UTC 2017 : Endpoint request body after
transformations:
{"resource":"/pricing/test","path":"/pricing/test","httpMethod":"GET","headers":null,"queryStringParameters":{"name":"ciao", "surname":"bonjour"},"pathParameters":null,"stageVariables":null,
...
注意:
我遵循这条路径是因为我觉得将 @BeanProperty queryStringParameters: Map[String, String]
中的 Map
替换为类型 T 会方便且富有表现力,例如
case class Person(@beanProperty val name: String, @beanProperty val surname: String)
然而,上面的代码将 {"name":"ciao", "surname":"bonjour"}
视为一个 String
,但没有弄清楚它应该反序列化该字符串。
编辑
我也曾尝试用 java.util.Map[String, String]
替换 scala 映射,但没有成功
最佳答案
默认情况下,Serverless 启用 proxy integration between the lambda and API Gateway .正如您所注意到的,这对您来说意味着 API Gateway 会将包含有关请求的所有元数据的对象传递到您的处理程序中:
Mon Sep 25 20:45:22 UTC 2017 : Endpoint request body after transformations: {"resource":"/pricing/test","path":"/pricing/test","httpMethod":"GET","headers":null,"queryStringParameters":{"name":"ciao", "surname":"bonjour"},"pathParameters":null,"stageVariables":null, ...
这显然不会映射到您的模型,该模型中只有字段 name
和 surname
。有几种方法可以解决这个问题。
1。调整你的模型
如果您通过使字段可变(并因此为它们创 build 置器)使您的类成为适当的 POJO,您对 HelloWorldRequest
类的尝试确实有效:
class HelloWorldRequest(
@BeanProperty var httpMethod: String,
@BeanProperty var headers: java.util.Map[String, String],
@BeanProperty var queryStringParameters: java.util.Map[String, String]
) extends ApiGatewayGetRequest(httpMethod, headers, queryStringParameters) {
AWS Lambda 文档 states :
The get and set methods are required in order for the POJOs to work with AWS Lambda's built in JSON serializer.
另请记住,不支持 Scala 的 Map。
2。使用自定义请求模板
如果您不需要元数据,那么您可以使用 mapping templates 让 API 网关仅将您需要的数据传递到 lambda 中,而不是更改您的模型。 .
为此,您需要告诉 Serverless 使用普通的 lambda 集成(而不是代理)和 specify a custom request template .
Amazon API Gateway 文档有 an example request template这对你的问题来说几乎是完美的。稍微调整一下,我们得到
functions:
pricing:
handler: pricing.ApiGatewayHandler
events:
- http:
path: pricing/test
method: get
integration: lambda
request:
template:
application/json: |
#set($params = $input.params().querystring)
{
#foreach($paramName in $params.keySet())
"$paramName" : "$util.escapeJavaScript($params.get($paramName))"
#if($foreach.hasNext),#end
#end
}
此模板将从查询字符串参数中生成一个 JSON,现在它将成为 lambda 的输入:
Endpoint request body after transformations: { "name" : "ciao" }
哪个正确映射到您的模型。
请注意,禁用代理集成也会更改响应格式。您会注意到现在您的 API 直接返回您的响应模型:
{"statusCode":200,"body":"{\"message\":\"Hello ciao\"}","headers":{"x-foo":"coucou"},"base64Encoded":true}
您可以通过修改代码以仅返回正文或添加自定义响应模板来解决此问题:
response:
template: $input.path('$.body')
这会将输出转换为您所期望的,但会公然忽略 statusCode
和 headers
。您需要进行更复杂的响应配置来处理这些问题。
3。自己做映射
不是扩展 RequestHandler
并让 AWS Lambda 将 JSON 映射到 POJO,you can instead extend RequestStreamHandler
,它将为您提供一个 InputStream
和一个 OutputStream
,因此您可以使用您选择的 JSON 序列化程序进行(反)序列化。
关于java - AWS Lambda - Java Bean,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/46412929/