Question

我已经创建了Lambda函数，将其订阅了SNS主题，并且试图将SNS消息中的值传递给Nodejs中的CloudFormation createStack函数。 SNS消息仅包含一个数字，该数字将转换为变量并传递给我的create_stack_function。从那里，我不确定如何正确传递它。模板需要一个名为InstanceNumber的值，该值告诉它要创建的主机数。

topic_arn = "arn:aws:sns:us-west-2:xxxxxxxxxxxx:xxxxxxxxxxxxxxx";
var AWS = require('aws-sdk'); 
AWS.config.region_array = topic_arn.split(':'); // splits the ARN in to and array 
AWS.config.region = AWS.config.region_array[3];  // makes the 4th variable in the array (will always be the region)


// Searches SNS messages for number of hosts to create
exports.handler = function (event, context) {
    const message = event.Records[0].Sns.Message;
        var NumberOfHosts = message;

        return create_stack_function(NumberOfHosts);

    // Might change return value, but all code branches should return.
    return true;
};

// Creates stack and publishes number of instances to the send_SNS_notification function
async function create_stack_function(NumberOfHosts) {
    const cloudformation = new AWS.CloudFormation();

    try {
        const resources = await cloudformation.createStack({
            StackName: "Launch-Test",
            TemplateURL: "https://s3-us-west-2.amazonaws.com/cf-templates-xxxxxxxxxxx-us-west-2/xxxinstances.yaml",
            InstanceNumber: NumberOfHosts,
        }).promise();
        return send_SNS_notification(NumberOfHosts);
    } catch(err) {
        console.log(err, err.stack);
    }
}
// Publishes message to SNS
async function send_SNS_notification(NumberOfHosts) {
    const sns = new AWS.SNS();
    const resources_str = JSON.stringify(NumberOfHosts);

    try {
        const data = await sns.publish({
            Subject: "CloudFormation Stack Created",
            Message:  "A new stack was created containing" + NumberOfHosts + "host(s).",
            TopicArn: topic_arn
        }).promise();

        console.log('push sent');
        console.log(data);
    } catch (err) {
        console.log(err.stack);
    }
}

我希望此Lambda函数接收SNS消息，将其转换为变量，创建CloudFormation堆栈，并发送有关正在创建的堆栈的SNS消息。

Answer 1

根据docs，您传入一个Parameters参数，该参数是一个对象数组，每个对象至少包含名称（ParameterKey）和值（{{ 1}}）中要传递给Cloudformation的参数。

尝试以下操作：

ParameterValue

使用Node.js将参数传递给CloudFormation函数

1 个答案: