Object Storage Service:Multipart upload using OSS SDK for Node.js

Background information

The multipartUpload method is designed for large objects. It splits an object into parts and uploads them individually. If an upload is interrupted, you can resume it, and only the failed or missing parts will be re-uploaded, saving time and bandwidth.

If the ConnectionTimeoutError error occurs when you use the MultipartUpload method, you need to fix the error. You can reduce the part size, extend the timeout period, or resend the request. You can also capture the ConnectionTimeoutError error and fix the error based on the cause. For more information, see Network connection timeout handling.

The table below outlines the parameters that can be configured during a multipart object upload.

Multipart upload example

The following sample code provides an example on how to use the multipartUpload method to perform multipart upload:

const OSS = require('ali-oss');
const path = require("path");

const client = new OSS({
  // Specify the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the region to oss-cn-hangzhou. 
  region: 'yourregion',
  // Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured. 
  accessKeyId: process.env.OSS_ACCESS_KEY_ID,
  accessKeySecret: process.env.OSS_ACCESS_KEY_SECRET,
  authorizationV4: true,
  // Specify the name of the bucket. 
  bucket: 'yourbucketname',
});


const progress = (p, _checkpoint) => {
  // Record the upload progress of the object. 
  console.log(p); 
  // Record the checkpoint information about the multipart upload task. 
  console.log(_checkpoint); 
};

const headers = {  
  // Specify the storage class of the object. 
  'x-oss-storage-class': 'Standard', 
  // Specify tags for the object. You can specify multiple tags for the object. 
  'x-oss-tagging': 'Tag1=1&Tag2=2', 
  // Specify whether to overwite an existing object with the same name when the multipart upload task is initialized. In this example, this parameter is set to true, which indicates that an existing object with the same name as the object to upload is not overwritten. 
  'x-oss-forbid-overwrite': 'true'
}

// Start the multipart upload task. 
async function multipartUpload() {
  try {
    // Specify the full path of the object. Example: exampledir/exampleobject.txt. Then, specify the full path of the local file. Example: D:\\localpath\\examplefile.txt. Do not include the bucket name in the full path. 
    // By default, if you set this parameter to the name of a local file such as examplefile.txt without specifying the local path, the local file is uploaded from the local path of the project to which the sample program belongs. 
    const result = await client.multipartUpload('exampledir/exampleobject.txt', path.normalize('D:\\localpath\\examplefile.txt'), {
      progress,
      // headers,
      // Configure the meta parameter to specify metadata for the object. You can call the HeadObject operation to obtain the object metadata. 
      meta: {
        year: 2020,
        people: 'test',
      },
    });
    console.log(result);
    // Specify the full path of the object. Example: exampledir/exampleobject.txt. Do not include the bucket name in the full path. 
    const head = await client.head('exampledir/exampleobject.txt');
    console.log(head);
  } catch (e) {
    // Handle timeout exceptions. 
    if (e.code === 'ConnectionTimeoutError') {
      console.log('TimeoutError');
      // do ConnectionTimeoutError operation
    }
    console.log(e);
  }
}

multipartUpload();

The multipartUpload method in the preceding code sample contains the initMultipartUpload, uploadPart, and completeMultipartUpload operations. If you want to perform multipart upload step by step, call the preceding operations in sequence. For more information, see .initMultipartUpload, .uploadPart, and .completeMultipartUpload.

Cancel a multipart upload task

Use the client.abortMultipartUpload method to cancel a multipart upload task. If you cancel a multipart upload task, you cannot use the upload ID to upload parts and the uploaded parts are deleted.

The following sample code provides an example on how to cancel a multipart upload task.

const OSS = require("ali-oss");

const client = new OSS({
  // Specify the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the region to oss-cn-hangzhou. 
  region: "yourregion",
  // Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured. 
  accessKeyId: process.env.OSS_ACCESS_KEY_ID,
  accessKeySecret: process.env.OSS_ACCESS_KEY_SECRET,
  authorizationV4: true,
  // Specify the name of the bucket. 
  bucket: "yourbucketname",
});

async function abortMultipartUpload() {
  // Specify the full path of the object. Example: exampledir/exampleobject.txt. Do not include the bucket name in the full path. 
  const name = "exampledir/exampleobject.txt";
  // Specify the upload ID. You can obtain the upload ID from the response to the InitiateMultipartUpload operation. 
  const uploadId = "0004B999EF518A1FE585B0C9360D****";
  const result = await client.abortMultipartUpload(name, uploadId);
  console.log(result);
}

abortMultipartUpload();

List multipart upload tasks

Use the client.listUploads method to list all ongoing multipart upload tasks, which are tasks that have been initiated but are not completed or canceled.

const OSS = require("ali-oss");

const client = new OSS({
  // Specify the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the region to oss-cn-hangzhou. 
  region: "yourregion",
  // Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured. 
  accessKeyId: process.env.OSS_ACCESS_KEY_ID,
  accessKeySecret: process.env.OSS_ACCESS_KEY_SECRET,
  authorizationV4: true,
  // Specify the name of the bucket. 
  bucket: "yourbucketname",
});

async function listUploads(query = {}) {
  // You can configure the following parameters for query: prefix, marker, delimiter, upload-id-marker, and max-uploads. 
  const result = await client.listUploads(query);

  result.uploads.forEach((upload) => {
    // Specify the upload IDs of the multipart upload tasks. 
    console.log(upload.uploadId);
    // Combine all parts into a complete object and specify the full path of the object. 
    console.log(upload.name);
  });
}

const query = {
  // Specify the maximum number of multipart upload tasks to return for the current list operation. The default value and the maximum value of max-uploads are both 1000. 
  "max-uploads": 1000,
};
listUploads(query);

List uploaded parts

Use the client.listParts method to list all parts that are uploaded by using the multipart upload task with the specified upload ID.

const OSS = require("ali-oss");

const client = new OSS({
  // Specify the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the region to oss-cn-hangzhou. 
  region: "yourregion",
  // Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured. 
  accessKeyId: process.env.OSS_ACCESS_KEY_ID,
  accessKeySecret: process.env.OSS_ACCESS_KEY_SECRET,
  authorizationV4: true,
  // Specify the name of the bucket. 
  bucket: "yourbucketname",
});

async function listParts() {
  const query = {
    // Specify the maximum number of parts to return for the current list operation. The default value and the maximum value of max-parts are both 1000. 
    "max-parts": 1000,
  };
  let result;
  do { 
    result = await client.listParts(
      // Specify the full path of the object. Example: exampledir/exampleobject.txt. Do not include the bucket name in the full path. 
      "exampledir/exampleobject.txt",
      // Obtain the upload ID from the response to the InitiateMultipartUpload operation. You must obtain the upload ID before you call the CompleteMultipartUpload operation to complete the multipart upload task.
      "0004B999EF518A1FE585B0C9360D****",
      query
    );
    // Specify the starting position of the next list operation. Only parts with part numbers greater than the value of this parameter are listed. 
    query["part-number-marker"] = result.nextPartNumberMarker;
    result.parts.forEach((part) => {
      console.log(part.PartNumber);
      console.log(part.LastModified);
      console.log(part.ETag);
      console.log(part.Size);
    });
  } while (result.isTruncated === "true");
}

listParts();

References

• For the complete sample code for multipart upload, visit GitHub.

• The high-level multipartUpload method in the OSS SDK for Node.js internally wraps the following three low-level API operations:

  • InitiateMultipartUpload

  • UploadPart

  • CompleteMultipartUpload

• For more details on the underlying API operations, see the following topics:

  • AbortMultipartUpload: Cancels an in-progress multipart upload task and deletes any uploaded parts.

  • ListParts: Lists all successfully uploaded parts for a specific upload task.

  • ListMultipartUploads: Lists all multipart upload tasks that are currently in progress (initiated but not yet completed or aborted).