Amazon web services SNSEvent对象'；s getRecords（）返回null

我创建并部署了一个用Java编写的简单Lambda函数。我似乎有几个问题

首先，SNSEvent对象的getRecords（）方法调用返回null，我不知道为什么。我试着在SNS内部进行测试，但由于第二个问题，这不起作用

其次，Cloudwatch似乎没有从Lambda函数接收任何日志。如果没有Cloudwatch日志，我在SNS测试时无法看到任何日志

下面是Lambda函数的相关代码

public void articleHandler(SNSEvent articleMsg, Context context) {
    LambdaLogger logger = context.getLogger();

    if (articleMsg.getRecords() == null) {
        logger.log("Getrecords is null");
        System.exit(1);
    }
    for (SNSEvent.SNSRecord msg : articleMsg.getRecords()) {
        try {
            logger.log("Getting headline records");
            JsonObject headline = getMessageAsJsonObject(msg.getSNS().getMessage());
            if (headline.has("link") && headline.get("link").isJsonPrimitive() && headline.get("link").getAsJsonPrimitive().isString()) {
                headline.addProperty("body", getArticleBody(headline.get("link").getAsString()));
                logger.log(headline.toString());
            } else {
                throw new InvalidJSONException("\"link\" field either doesn't exist or is not a String primitive", headline.toString());
            }
        } catch (InvalidJSONException ex) {
            logger.log(ex.toString());
        } catch (IOException | SAXException | TikaException ex) {
            logger.log(ex.getMessage());
        }
    }

}

<dependencies>
    <dependency>
        <groupId>com.amazonaws</groupId>
        <artifactId>aws-lambda-java-core</artifactId>
        <version>1.0.0</version>
        <type>jar</type>
    </dependency>
    <dependency>
        <groupId>log4j</groupId>
        <artifactId>log4j</artifactId>
        <version>1.2.17</version>
        <type>jar</type>
    </dependency>
    <dependency>
        <groupId>com.amazonaws</groupId>
        <artifactId>aws-lambda-java-events</artifactId>
        <version>1.1.0</version>
    </dependency>
    <dependency>
        <groupId>org.apache.tika</groupId>
        <artifactId>tika-parsers</artifactId>
        <version>1.11</version>
    </dependency>
    <dependency>
        <groupId>com.google.code.gson</groupId>
        <artifactId>gson</artifactId>
        <version>2.5</version>
        <type>jar</type>
    </dependency>
</dependencies>
<properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <maven.compiler.source>1.8</maven.compiler.source>
    <maven.compiler.target>1.8</maven.compiler.target>
</properties>
<build>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-shade-plugin</artifactId>
            <version>2.4.3</version>
            <configuration>
                <createDependencyReducedPom>false</createDependencyReducedPom>
            </configuration>
            <executions>
                <execution>
                    <phase>package</phase>
                    <goals>
                        <goal>shade</goal>
                    </goals>
                </execution>
            </executions>
        </plugin>
    </plugins>
</build>

下面是我的pom文件。我尝试将aws lambda java core和aws lambda java events设置为相同的版本，但这并没有改变任何东西，我将其放回1.0.0和1.1.0版本，因为这是在不同的lambda函数中工作的

public void articleHandler(SNSEvent articleMsg, Context context) {
    LambdaLogger logger = context.getLogger();

    if (articleMsg.getRecords() == null) {
        logger.log("Getrecords is null");
        System.exit(1);
    }
    for (SNSEvent.SNSRecord msg : articleMsg.getRecords()) {
        try {
            logger.log("Getting headline records");
            JsonObject headline = getMessageAsJsonObject(msg.getSNS().getMessage());
            if (headline.has("link") && headline.get("link").isJsonPrimitive() && headline.get("link").getAsJsonPrimitive().isString()) {
                headline.addProperty("body", getArticleBody(headline.get("link").getAsString()));
                logger.log(headline.toString());
            } else {
                throw new InvalidJSONException("\"link\" field either doesn't exist or is not a String primitive", headline.toString());
            }
        } catch (InvalidJSONException ex) {
            logger.log(ex.toString());
        } catch (IOException | SAXException | TikaException ex) {
            logger.log(ex.getMessage());
        }
    }

}

<dependencies>
    <dependency>
        <groupId>com.amazonaws</groupId>
        <artifactId>aws-lambda-java-core</artifactId>
        <version>1.0.0</version>
        <type>jar</type>
    </dependency>
    <dependency>
        <groupId>log4j</groupId>
        <artifactId>log4j</artifactId>
        <version>1.2.17</version>
        <type>jar</type>
    </dependency>
    <dependency>
        <groupId>com.amazonaws</groupId>
        <artifactId>aws-lambda-java-events</artifactId>
        <version>1.1.0</version>
    </dependency>
    <dependency>
        <groupId>org.apache.tika</groupId>
        <artifactId>tika-parsers</artifactId>
        <version>1.11</version>
    </dependency>
    <dependency>
        <groupId>com.google.code.gson</groupId>
        <artifactId>gson</artifactId>
        <version>2.5</version>
        <type>jar</type>
    </dependency>
</dependencies>
<properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <maven.compiler.source>1.8</maven.compiler.source>
    <maven.compiler.target>1.8</maven.compiler.target>
</properties>
<build>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-shade-plugin</artifactId>
            <version>2.4.3</version>
            <configuration>
                <createDependencyReducedPom>false</createDependencyReducedPom>
            </configuration>
            <executions>
                <execution>
                    <phase>package</phase>
                    <goals>
                        <goal>shade</goal>
                    </goals>
                </execution>
            </executions>
        </plugin>
    </plugins>
</build>

由于Cloudwatch没有报告任何日志，我只能看到Lambda控制台报告的内容：

{
  "errorMessage": "Process exited before completing request"
}

如果我从函数中删除If（articleMsg.getRecords（）==null）语句，则在Lambda控制台中会出现以下错误

{   "errorMessage": "java.lang.NullPointerException",   "errorType": "java.lang.NullPointerException",   "stackTrace": [
    "com.myapp.articlehandler.LambdaHandler.articleHandler(LambdaHandler.java:35)",
    "sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)",
    "sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)",
    "sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)",
    "java.lang.reflect.Method.invoke(Method.java:497)"] 
}

LambdaHandler.java中的第35行（上面粘贴的代码）是指：

for (SNSEvent.SNSRecord msg : articleMsg.getRecords()) {

最后，当我单击错误“Execution result:failed（logs）”中的链接以查看Cloudwatch日志时，Cloudwatch会打开并给出以下错误，并且不会显示此Lambda函数的任何日志：

加载日志流时出错。请通过刷新重试 这一页

这两个问题似乎并不相关，尽管我不能确定

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有人对其中一个/两个问题都有什么建议吗？

我在为迪纳摩触发lambdas时遇到了同样的问题db@Tisha对不起，我不记得是怎么回事了。我应该发布一篇后续文章……我能说的是，通常当我遇到这样的问题时，这是因为发送到Lambda函数的JSON有问题。我在为dynamo触发lambdas时也面临同样的问题db@Tisha对不起，我不记得是怎么回事了。我应该发布一篇后续文章……我能说的是，通常当我遇到这样的问题时，这是因为发送到Lambda函数的JSON有问题。