Zig

S3 Complete a Multipart Upload

See more Amazon S3 (new) Examples

This operation completes a multipart upload by assembling previously uploaded parts.

Processing of a Complete Multipart Upload request could take several minutes to complete. After Amazon S3 begins processing the request, it sends an HTTP response header that specifies a 200 OK response. While processing is in progress, Amazon S3 periodically sends whitespace characters to keep the connection from timing out. Because a request could fail after the initial 200 OK response has been sent, it is important that you check the response body to determine whether the request succeeded.

This example sends a POST request to complete a multipart upload, which looks like this:

POST /ObjectName?uploadId=UploadId HTTP/1.1
Host: BucketName.s3.amazonaws.com
Date: Date
Content-Length: Size
Authorization: authorization string

<CompleteMultipartUpload>
  <Part>
    <PartNumber>PartNumber</PartNumber>
    <ETag>ETag</ETag>
  </Part>
  ...
</CompleteMultipartUpload>

Zig

const std = @import("std");
const chilkat = @import("chilkat");

pub fn main(init: std.process.Init) !void {
    const alloc = init.arena.allocator();

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    // The 1st step in an S3 multipart upload is to initiate it,
    // as shown here: Initiate S3 Multipart Upload

    // The 2nd step is to upload the parts
    // as shown here: S3 Upload Parts

    // The 3rd and final step (this example) is to complete the multipart upload.

    // Other S3 Multipart Upload Examples:
    // Abort Multipart Upload
    // List Parts

    // When the multipart upload was initiated, an UploadId was provided in the XML response, and it
    // was saved to a file.  Steps 2 and 3 begin by loading the XML and getting
    // the Upload ID.

    const xml_init = try chilkat.Xml.init();
    defer xml_init.deinit();
    xml_init.loadXmlFile("s3_multipart_uploads/initiate.xml") catch {
        std.debug.print("Did not find the initiate.xml XML file.\n", .{});
        return;
    };

    const upload_id = try xml_init.getChildContent(alloc, "UploadId");
    std.debug.print("UploadId = {s}\n", .{upload_id});

    // We'll also need the XML file that contains a record of the parts
    // with part numbers and ETags.  (This file was produced when parts were being uploaded.)
    const xml_parts_list = try chilkat.Xml.init();
    defer xml_parts_list.deinit();
    xml_parts_list.loadXmlFile("s3_multipart_uploads/partsList.xml") catch {
        std.debug.print("Did not find the partsList.xml XML file.\n", .{});
        return;
    };

    const rest = try chilkat.Rest.init();
    defer rest.deinit();

    // Connect to the Amazon AWS REST server.
    const b_tls = true;
    const port = 443;
    const b_auto_reconnect = true;
    try rest.connect("s3.amazonaws.com", port, b_tls, b_auto_reconnect);

    // ----------------------------------------------------------------------------
    // Important: For buckets created in regions outside us-east-1,
    // there are three important changes that need to be made.
    // See Working with S3 Buckets in Non-us-east-1 Regions for the details.
    // ----------------------------------------------------------------------------

    // Provide AWS credentials for the REST call.
    const auth_aws = try chilkat.AuthAws.init();
    defer auth_aws.deinit();
    auth_aws.setAccessKey("AWS_ACCESS_KEY");
    auth_aws.setSecretKey("AWS_SECRET_KEY");
    auth_aws.setServiceName("s3");

    try rest.setAuthAws(auth_aws);

    // Set the bucket name via the HOST header.
    // In this case, the bucket name is "chilkat100".
    rest.setHost("chilkat100.s3.amazonaws.com");

    // The "uploadId=UploadId" must be added as a query parameter.  This allows it to be
    // incorporated into the AWS signature calculation, which is a requirement.
    // Therefore, we use AddQueryParam:
    rest.addQueryParam("uploadId", upload_id) catch {};

    // Our ObjectName in this case is "somethingBig.zip".
    const response_xml = rest.fullRequestString(alloc, "POST", "/somethingBig.zip", try xml_parts_list.getXml(alloc)) catch {
        std.debug.print("{s}\n", .{try rest.getLastErrorText(alloc)});
        return;
    };

    // When successful, the S3 Storage service will respond with a 200 response code,
    // with an XML body.
    if (rest.getResponseStatusCode() != 200) {
        // Examine the request/response to see what happened.
        std.debug.print("response status code = {d}\n", .{rest.getResponseStatusCode()});
        std.debug.print("response status text = {s}\n", .{try rest.getResponseStatusText(alloc)});
        std.debug.print("response header: {s}\n", .{try rest.getResponseHeader(alloc)});
        std.debug.print("response body: {s}\n", .{response_xml});
        std.debug.print("---\n", .{});
        std.debug.print("LastRequestStartLine: {s}\n", .{try rest.getLastRequestStartLine(alloc)});
        std.debug.print("LastRequestHeader: {s}\n", .{try rest.getLastRequestHeader(alloc)});
    }

    // Load the XML response into Chilkat XMl and emit via GetXml to see the XML in a pretty-printed (indented) readable format.
    const xml = try chilkat.Xml.init();
    defer xml.deinit();
    xml.loadXml(response_xml) catch {};
    std.debug.print("{s}\n", .{try xml.getXml(alloc)});
    std.debug.print("----\n", .{});

    std.debug.print("Multipart upload completed.\n", .{});
}