使用打字稿向 AWS Elasticsearch Service 发出签名请求

Question

我需要的是使用 typescript lambda 将流数据从 DynamoDB 加载到 Amazon Elasticsearch Service。

流数据按预期到达，但我无法弄清楚如何使用签名对 HTTP 请求进行身份验证。 AWS 似乎有一些私有 API 用于签署和发出此 JS 代码中引用的 HTTP 请求（用于将数据从 S3 加载到 ES）：

/*
 * Add the given document to the ES domain.
 * If all records are successfully added, indicate success to lambda
 * (using the "context" parameter).
 */
function postDocumentToES(doc, context) {
    var req = new AWS.HttpRequest(endpoint);

    req.method = 'POST';
    req.path = path.join('/', esDomain.index, esDomain.doctype);
    req.region = esDomain.region;
    req.body = doc;
    req.headers['presigned-expires'] = false;
    req.headers['Host'] = endpoint.host;

    // Sign the request (Sigv4)
    var signer = new AWS.Signers.V4(req, 'es');
    signer.addAuthorization(creds, new Date());

    // Post document to ES
    var send = new AWS.NodeHttpClient();
    send.handleRequest(req, null, function(httpResp) {
        var body = '';
        httpResp.on('data', function (chunk) {
            body += chunk;
        });
        httpResp.on('end', function (chunk) {
            numDocsAdded ++;
            if (numDocsAdded === totLogLines) {
                // Mark lambda success.  If not done so, it will be retried.
                console.log('All ' + numDocsAdded + ' log records added to ES.');
                context.succeed();
            }
        });
    }, function(err) {
        console.log('Error: ' + err);
        console.log(numDocsAdded + 'of ' + totLogLines + ' log records added to ES.');
        context.fail();
    });
}

来源： https : //github.com/aws-samples/amazon-elasticsearch-lambda-samples/blob/master/src/s3_lambda_es.js

但是在用 TS 编写时，我似乎无法导入Signers.V4或NodeHttpClient库，我猜是因为它们是“私有 API”。

另一个令人困惑的因素是，在本文档中，我们被告知 aws-sdk 会自动对传出请求进行身份验证，而我们不需要自己进行身份验证： https : //docs.aws.amazon.com/general/latest/gr/ signing_aws_api_requests.html

任何人都可以对如何使用 TypeScript 进行身份验证/签名并将带有 AWS Lambda 凭证的 http 请求发送到 AWS 服务（如 Elasticsearch）有一些见解吗？

Answer 1

这是我对与 Amazon Elasticsearch AWS4 签名请求兼容的 Elasticsearch 客户端的实现：

import { Client } from "@elastic/elasticsearch";
import * as AWS4 from "aws4";
import { Connection } from "@elastic/elasticsearch";
import { ConnectionOptions } from "@elastic/elasticsearch/lib/Connection";
import * as http from "http";
import { Readable } from "stream";

interface RequestOptions extends http.ClientRequestArgs {
    asStream?: boolean;
    body?: string | Buffer | Readable | null;
    querystring?: string;
}

class AwsEsConnection extends Connection {
    constructor(opts?: ConnectionOptions) {
        super(opts);
    }

    getBodyString(body?: string | Buffer | Readable | null): string | null {
        if (!body) {
            return body as null;
        }

        if (typeof body === "string" || body instanceof String) {
            return body as string;
        }

        if (body instanceof Buffer) {
            return body.toString();
        }

        if (body instanceof Readable) {
            throw new Error("Haven't implemented stream handling!!");
        }

        return body;
    }

    public request(
        params: RequestOptions,
        callback: (
            err: Error | null,
            response: http.IncomingMessage | null
        ) => void
    ): http.ClientRequest {
        const body = this.getBodyString(params.body);
        const opts = {
            method: params.method,
            host: params.host,
            path: `${params.path}?${params.querystring}`,
            service: "es",
            region: "eu-west-1",
            body: body,
            headers: params.headers
        };

        AWS4.sign(opts);

        params.headers = opts.headers;
        params.body = opts.body;

        return super.request(params, callback);
    }
}

export class ElasticClientFactory {
    constructor(
        private esClusterBaseUrl: string,
    ) {}

    create(): Client {
        return new Client({
            node: this.esClusterBaseUrl,
            Connection: AwsEsConnection
        });
    }
}

Answer 2

我用这个包也有很好的结果，它在引擎盖下做同样的事情，本质上：

https://www.npmjs.com/package/aws-elasticsearch-connector