AWS DevOps Agent (Preview)をPagerDutyからトリガーしてみた #AWSreInvent

// index.mjs
import { createHmac } from "node:crypto";
import https from "node:https";
import { URL } from "node:url";

const EVENT_AI_WEBHOOK_URL = process.env.EVENT_AI_WEBHOOK_URL;
const EVENT_AI_SECRET = process.env.EVENT_AI_SECRET;
const AWS_ACCOUNT_ID = process.env.AWS_ACCOUNT_ID || "unknown";
const AWS_REGION = process.env.AWS_REGION || "us-east-1";

export const handler = async (event) => {
  try {
    console.log("Raw event:", JSON.stringify(event, null, 2));
    if (event.source !== "pagerduty") {
      console.warn("Not a PagerDuty event, skipping:", event.source);
      return { statusCode: 200, body: "Not a PagerDuty event, ignored" };
    }
    const payload = processPagerDutyEvent(event);
    const response = await sendToEventAi(payload);
    console.log("event-ai response:", response.statusCode, response.body);
    return response;
  } catch (err) {
    console.error("Error in event handler:", err);
    return { statusCode: 500, body: "Internal server error" };
  }
};

function processPagerDutyEvent(event) {
  console.log("Processing PagerDuty event");
  const incidentId = event.incident_id || "";
  const incidentTitle = event.incident_title || "PagerDuty Incident";
  const incidentStatus = event.incident_status || "";
  const incidentUrl = event.incident_url || "";
  // alert_detailsからCloudWatch Alarm情報を取得
  const alertDetails = event.alert_details?.body?.details || {};
  const cefDetails = event.alert_details?.body?.cef_details || {};
  const trigger = alertDetails.Trigger || {};
  const dimensions = trigger.Dimensions || [];
  // timestampは現在時刻を使用（重複回避のため）
  const timestamp = new Date().toISOString();
  // descriptionを構築（alert_detailsから詳細情報を取得）
  const descriptionLines = [];
  descriptionLines.push("Please respond in Japanese.");
  descriptionLines.push(`Status: ${incidentStatus}`);
  if (alertDetails.NewStateReason) {
    descriptionLines.push(`Reason: ${alertDetails.NewStateReason}`);
  }
  // Lambda関数名をDimensionsから取得
  const functionDim = dimensions.find(d => d.name === "FunctionName");
  if (functionDim?.value) {
    descriptionLines.push(`Lambda Function: ${functionDim.value}`);
  }
  if (trigger.Namespace && trigger.MetricName) {
    descriptionLines.push(`Metric: ${trigger.Namespace}/${trigger.MetricName}`);
  }
  if (alertDetails.AlarmName) {
    descriptionLines.push(`Alarm Name: ${alertDetails.AlarmName}`);
  }
  if (alertDetails.Region) {
    descriptionLines.push(`Region: ${alertDetails.Region}`);
  }
  if (alertDetails.AWSAccountId) {
    descriptionLines.push(`Account ID: ${alertDetails.AWSAccountId}`);
  }
  if (alertDetails.StateChangeTime) {
    descriptionLines.push(`Incident Time: ${alertDetails.StateChangeTime}`);
  }
  if (incidentUrl) {
    descriptionLines.push(`URL: ${incidentUrl}`);
  }
  const description = descriptionLines.join("\n");
  // affectedResources: alert_detailsからARNを取得
  const affectedResources = [];
  if (alertDetails.AlarmArn) {
    affectedResources.push(alertDetails.AlarmArn);
  }
  if (cefDetails.source_origin) {
    affectedResources.push(cefDetails.source_origin);
  }
  // alert_detailsにARNがない場合はダミーARNを生成
  if (affectedResources.length === 0) {
    affectedResources.push(`arn:aws:pagerduty:${AWS_REGION}:${AWS_ACCOUNT_ID}:incident/${incidentId}`);
  }
  return {
    eventType: "incident",
    incidentId: `pagerduty:${incidentId}`,
    action: "created",
    priority: "HIGH",
    title: incidentTitle,
    description,
    timestamp,
    service: "pagerduty",
    affectedResources
  };
}

async function sendToEventAi(payload) {
  const payloadString = JSON.stringify(payload);
  const tsHeader = new Date().toISOString();
  const hmac = createHmac("sha256", EVENT_AI_SECRET);
  hmac.update(`${tsHeader}:${payloadString}`, "utf8");
  const signature = hmac.digest("base64");
  const url = new URL(EVENT_AI_WEBHOOK_URL);
  const options = {
    hostname: url.hostname,
    path: url.pathname + url.search,
    method: "POST",
    port: url.port || 443,
    headers: {
      "Content-Type": "application/json",
      "x-amzn-event-timestamp": tsHeader,
      "x-amzn-event-signature": signature,
      "Content-Length": Buffer.byteLength(payloadString)
    }
  };
  console.log("Sending payload to event-ai:", JSON.stringify(payload, null, 2));
  console.log("Request headers - timestamp:", tsHeader, "signature:", signature);
  return new Promise((resolve, reject) => {
    const req = https.request(options, (res) => {
      let data = "";
      res.on("data", (chunk) => {
        data += chunk;
      });
      res.on("end", () => {
        resolve({
          statusCode: res.statusCode || 200,
          body: data
        });
      });
    });
    req.on("error", (err) => reject(err));
    req.write(payloadString);
    req.end();
  });
}

{
  "source": "pagerduty",
  "incident_id": "{{incident.id}}",
  "incident_title": "{{incident.title}}",
  "incident_status": "{{incident.status}}",
  "incident_url": "{{incident.url}}",
  "created_at": "{{incident.created_at}}",
  "alert_details": {{steps['Get Alerts for an Incident'].fields['First Alert Details']}}
}

Amazon.Runtime.Internal.HttpErrorResponseException