createCurlForS3UsingIAMCreds.js

const crypto = require("crypto");

const fetchData = (fetchURL) => {
    fetch(fetchURL, {
        headers,
    })
        .then((response) => {
            console.log("Buckets:", response);
            const reader = response.body.getReader();
            let result = "";
            let done, value;

            (async () => {
                // console.log(await reader.read() );
                while (!done) {
                    const data = await reader.read();
                    done = data.done;
                    value = data.value;
                    result += new TextDecoder().decode(value);
                }
                console.log("Result:", result);
            })();
        })
        .catch((error) => {
            console.error(
                "Error:",
                error.response ? error.response.data : error.message
            );
        });
};

const createCURLCommand = (fetchURL, headers) => {
    const curlCommand = `curl -X GET '${fetchURL}' \\\n-H 'Authorization: ${headers["Authorization"]}' \\\n-H 'x-amz-date: ${headers["x-amz-date"]}' \\\n-H 'x-amz-security-token: ${headers["x-amz-security-token"]}' \\\n-H 'x-amz-content-sha256: ${headers["x-amz-content-sha256"]}'`;
    console.log("CURL command is:- \n\n\n", curlCommand);
};

const data = {
    AccessKeyId: "ASIA.....",
    Expiration: 1.727944934e9,
    SecretKey: "MAb....",
    SessionToken: "c6o6tw=",
};

const accessKeyId = data.AccessKeyId;
const secretAccessKey = data.SecretKey;
const sessionToken = data.SessionToken;
const region = "ap-south-1";
const service = "s3";

// Generate the current date and timestamp in the required formats
const date = new Date();
const amzDate = date.toISOString().replace(/[:-]|\.\d{3}/g, ""); // Format: YYYYMMDD'T'HHMMSS'Z'
const dateStamp = date.toISOString().slice(0, 10).replace(/-/g, ""); // Format: YYYYMMDD

// Create a canonical request
const canonicalUri = "/";
const canonicalQuerystring = "max-buckets=10";
const canonicalHeaders = `host:s3.${region}.amazonaws.com\nx-amz-content-sha256:UNSIGNED-PAYLOAD\nx-amz-date:${amzDate}\nx-amz-security-token:${sessionToken}\n`;
const signedHeaders =
    "host;x-amz-content-sha256;x-amz-date;x-amz-security-token";
const payloadHash = "UNSIGNED-PAYLOAD";

const canonicalRequest = [
    "GET",
    canonicalUri,
    canonicalQuerystring,
    canonicalHeaders,
    signedHeaders,
    payloadHash,
].join("\n");

// Create the string to sign
const credentialScope = `${dateStamp}/${region}/${service}/aws4_request`;
const stringToSign = [
    "AWS4-HMAC-SHA256",
    amzDate,
    credentialScope,
    crypto.createHash("sha256").update(canonicalRequest).digest("hex"),
].join("\n");

// Create the signing key
const kDate = crypto
    .createHmac("sha256", `AWS4${secretAccessKey}`)
    .update(dateStamp)
    .digest();
const kRegion = crypto.createHmac("sha256", kDate).update(region).digest();
const kService = crypto.createHmac("sha256", kRegion).update(service).digest();
const signingKey = crypto
    .createHmac("sha256", kService)
    .update("aws4_request")
    .digest();

// Create the signature
const signature = crypto
    .createHmac("sha256", signingKey)
    .update(stringToSign)
    .digest("hex");

// Create the authorization header
const authorizationHeader = [
    `AWS4-HMAC-SHA256 Credential=${accessKeyId}/${credentialScope},`,
    `SignedHeaders=${signedHeaders},`,
    `Signature=${signature}`,
].join(" ");

const headers = {
    Authorization: authorizationHeader,
    "x-amz-date": amzDate,
    "x-amz-security-token": sessionToken,
    "x-amz-content-sha256": payloadHash,
};

const fetchURL = `https://s3.${region}.amazonaws.com/?${canonicalQuerystring}`;

// fetchData(fetchURL);

createCURLCommand(fetchURL, headers);