Amazon Lambda上适用于Amazon Echo / Alexa的Java handleRequest()方法签名？
作者：互联网
我正在尝试创建一个用Java实现的Amazon Lambda函数,以便与Amazon Echo / Alexa一起使用.我正在使用Eclipse Mars作为IDE.
这是我的LambdaFunctionHandler,它将收到来自Alexa的请求,如下所示：
public class LambdaFunctionHandler implements RequestHandler<SpeechletRequestEnvelope, SpeechletResponse> {
@Override
public SpeechletResponse handleRequest(SpeechletRequestEnvelope input, Context context) {
context.getLogger().log("Input: " + input);
// TODO: implement your handler
return null;
}
}
但是,当尝试使用Alexa的示例JSON输入进行测试时,我在Eclipse中收到错误：
{“errorMessage”:”An error occurred during JSON parsing”,”errorType”:”java.lang.RuntimeException”,”stackTrace”:[],”cause”:{“errorMessage”:”Lcom/fasterxml/jackson/databind/ObjectMapper;”,”errorType”:”java.lang.NoClassDefFoundError”,”stackTrace”:[“java.lang.Class.getDeclaredFields0(Native
Method)”,”java.lang.Class.privateGetDeclaredFields(Class.java:2583)”,”java.lang.Class.getDeclaredFields(Class.java:1916)”,”com.fasterxml.jackson.databind.introspect.AnnotatedClass._findFields(AnnotatedClass.java:689)”,”com.fasterxml.jackson.databind.introspect.AnnotatedClass.resolveFields(AnnotatedClass.java:470)”,”com.fasterxml.jackson.databind.introspect.AnnotatedClass.fields(AnnotatedClass.java:282)”,”com.fasterxml.jackson.databind.introspect.POJOPropertiesCollector._addFields(POJOPropertiesCollector.java:390)”,”com.fasterxml.jackson.databind.introspect.POJOPropertiesCollector.collect(POJOPropertiesCollector.java:243)”,”com.fasterxml.jackson.databind.introspect.BasicClassIntrospector.collectProperties(BasicClassIntrospector.java:197)”,”com.fasterxml.jackson.databind.introspect.BasicClassIntrospector.forDeserialization(BasicClassIntrospector.java:110)”,”com.fasterxml.jackson.databind.introspect.BasicClassIntrospector.forDeserialization(BasicClassIntrospector.java:15)”,”com.fasterxml.jackson.databind.DeserializationConfig.introspect(DeserializationConfig.java:703)”,”com.fasterxml.jackson.databind.deser.DeserializerCache._createDeserializer(DeserializerCache.java:330)”,”com.fasterxml.jackson.databind.deser.DeserializerCache._createAndCache2(DeserializerCache.java:265)”,”com.fasterxml.jackson.databind.deser.DeserializerCache._createAndCacheValueDeserializer(DeserializerCache.java:245)”,”com.fasterxml.jackson.databind.deser.DeserializerCache.findValueDeserializer(DeserializerCache.java:143)”,”com.fasterxml.jackson.databind.DeserializationContext.findRootValueDeserializer(DeserializationContext.java:439)”,”com.fasterxml.jackson.databind.ObjectReader._prefetchRootDeserializer(ObjectReader.java:1588)”,”com.fasterxml.jackson.databind.ObjectReader.(ObjectReader.java:185)”,”com.fasterxml.jackson.databind.ObjectMapper._newReader(ObjectMapper.java:558)”,”com.fasterxml.jackson.databind.ObjectMapper.reader(ObjectMapper.java:3098)”],”cause”:{“errorMessage”:”com.fasterxml.jackson.databind.ObjectMapper”,”errorType”:”java.lang.ClassNotFoundException”,”stackTrace”:[“java.net.URLClassLoader.findClass(URLClassLoader.java:381)”,”java.lang.ClassLoader.loadClass(ClassLoader.java:424)”,”java.lang.ClassLoader.loadClass(ClassLoader.java:357)”,”java.lang.Class.getDeclaredFields0(Native
Method)”,”java.lang.Class.privateGetDeclaredFields(Class.java:2583)”,”java.lang.Class.getDeclaredFields(Class.java:1916)”,”com.fasterxml.jackson.databind.introspect.AnnotatedClass._findFields(AnnotatedClass.java:689)”,”com.fasterxml.jackson.databind.introspect.AnnotatedClass.resolveFields(AnnotatedClass.java:470)”,”com.fasterxml.jackson.databind.introspect.AnnotatedClass.fields(AnnotatedClass.java:282)”,”com.fasterxml.jackson.databind.introspect.POJOPropertiesCollector._addFields(POJOPropertiesCollector.java:390)”,”com.fasterxml.jackson.databind.introspect.POJOPropertiesCollector.collect(POJOPropertiesCollector.java:243)”,”com.fasterxml.jackson.databind.introspect.BasicClassIntrospector.collectProperties(BasicClassIntrospector.java:197)”,”com.fasterxml.jackson.databind.introspect.BasicClassIntrospector.forDeserialization(BasicClassIntrospector.java:110)”,”com.fasterxml.jackson.databind.introspect.BasicClassIntrospector.forDeserialization(BasicClassIntrospector.java:15)”,”com.fasterxml.jackson.databind.DeserializationConfig.introspect(DeserializationConfig.java:703)”,”com.fasterxml.jackson.databind.deser.DeserializerCache._createDeserializer(DeserializerCache.java:330)”,”com.fasterxml.jackson.databind.deser.DeserializerCache._createAndCache2(DeserializerCache.java:265)”,”com.fasterxml.jackson.databind.deser.DeserializerCache._createAndCacheValueDeserializer(DeserializerCache.java:245)”,”com.fasterxml.jackson.databind.deser.DeserializerCache.findValueDeserializer(DeserializerCache.java:143)”,”com.fasterxml.jackson.databind.DeserializationContext.findRootValueDeserializer(DeserializationContext.java:439)”,”com.fasterxml.jackson.databind.ObjectReader._prefetchRootDeserializer(ObjectReader.java:1588)”,”com.fasterxml.jackson.databind.ObjectReader.(ObjectReader.java:185)”,”com.fasterxml.jackson.databind.ObjectMapper._newReader(ObjectMapper.java:558)”,”com.fasterxml.jackson.databind.ObjectMapper.reader(ObjectMapper.java:3098)”]}}}
这是我的JSON输入(取自TestColors example在线)：
{
"session": {
"new": false,
"sessionId": "session1234",
"attributes": {},
"user": {
"userId": null
},
"application": {
"applicationId": "amzn1.echo-sdk-ams.app.[unique-value-here]"
}
},
"version": "1.0",
"request": {
"intent": {
"slots": {
"Color": {
"name": "Color",
"value": "red"
}
},
"name": "MyColorIsIntent"
},
"type": "IntentRequest",
"requestId": "request5678"
}
}
所以,显然Amazon SpeechletRequestEnvelope不是handleRequest()的正确输入类.
handleRequest()从Alexa接收请求的正确方法签名是什么？
我找不到适用于Alexa / Echo的Amazon Lambda的Java示例.
解决方法:
这是一个完整的工作示例：
public class LambdaFunctionHandler implements RequestStreamHandler {
@Override
public void handleRequest(InputStream inputStream, OutputStream output, Context context) throws IOException {
byte serializedSpeechletRequest[] = IOUtils.toByteArray(inputStream);
SpeechletRequestEnvelope requestEnvelope = SpeechletRequestEnvelope.fromJson(serializedSpeechletRequest);
SpeechletRequest speechletRequest = requestEnvelope.getRequest();
if (speechletRequest instanceof IntentRequest) {
IntentRequest ir = (IntentRequest) speechletRequest;
String outString = "IntentRequest name: " + ir.getIntent().getName();
context.getLogger().log(outString);
output.write(outString.getBytes());
}
}
}
请注意,此类实现RequestStreamHandler,而不是RequestHandler.
使用问题中的输入JSON,output.write(outString.getBytes())将导致Eclipse AWS Lambda控制台的输出：
==================== FUNCTION OUTPUT ====================
IntentRequest name: MyColorIsIntent
…而context.getLogger().log(outString);导致在线将相同的行写入Amazon Lambda控制台.
您还需要确保项目中有一个文件夹/ lib,并且需要包含以下JAR：
> commons-codec-1.6.jar
> commons-lang3-3.x.jar
> jackson-annotations-2.3.2.jar
> jackson-core-2.3.2.jar
> jackson-databind-2.3.2.jar
> JakartaCommons-IO-2.4.jar
> joda-time-2.3.jar
> log4j.1.2.17.jar
> servlet-api-3.0.jar
> slf4j-api-1.7.4.jar
> slf4j-log4j12-1.7.4.jar
> alexa-skills-kit-1.0.jar
这些JAR可以从Maven Central下载,也可以从AlexaSkillsKit.zip中的“第三方”子文件夹下载.
在Eclipse中,您需要刷新项目,以便它看到/ lib目录中的JAR文件(只需按F5),然后将JAR添加到Java构建路径：
>在Eclipse中右键单击Lambda项目的根目录
>点击“属性”
>选择“Java Build Path”
>选择“库”选项卡
>点击“添加JAR”
>浏览到“lib”
>选择“lib”文件夹中的所有JAR,然后单击“确定”,直到返回主Eclipse屏幕
感谢@jephers指向Github上这个伟大教程的指针,我把它拼凑在一起：
https://github.com/jjaquinta/EchoProofOfConcepts/tree/master/jo.echo.lambda
标签：alexa-skills-kit,alexa-skill,java,amazon-web-services,aws-lambda 来源： https://codeday.me/bug/20190824/1708594.html