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Listing Versioning Objects

If you have any questions during development, post them on the Issues page of GitHub. For details about parameters and usage of each API, see the API Reference

You can call ObsClient.ListVersions to list versioning objects.

The following table describes the parameters involved in this API.

Parameter

Description

Property in OBS .NET SDK

BucketName

Bucket name

ListVersionsRequest.BucketName

Prefix

Name prefix that the objects to be listed must contain

ListVersionsRequest.Prefix

KeyMarker

Object name to start with when listing versioning objects in a bucket. All versioning objects following this parameter are listed in the lexicographical order.

ListVersionsRequest.KeyMarker

MaxKeys

Maximum number of listed versioning objects. The value ranges from 1 to 1000. If the value is not in this range, 1000 versioning objects are returned by default.

ListVersionsRequest.MaxKeys

Delimiter

Character used to group object names. If the object name contains the Delimiter parameter, the character string from the first character to the first delimiter in the object name is grouped under a single result element, CommonPrefix. (If a prefix is specified in the request, the prefix must be removed from the object name.)

ListVersionsRequest.Delimiter

VersionIdMarker

Object name to start with when listing versioning objects in a bucket. All versioning objects are listed in the lexicographical order by object name and version ID. This parameter must be used together with KeyMarker.

ListVersionsRequest.VersionIdMarker
  • If the value of VersionIdMarker is not a version ID specified by KeyMarker, VersionIdMarker is ineffective.
  • The returned result of ObsClient.ListVersions includes the versioning objects and delete markers.

Listing Versioning Objects in Simple Mode

The following sample code shows how to list versioning objects in simple mode. A maximum of 1000 versioning objects can be returned.

// Create an instance of ObsClient.
ObsClient client = new ObsClient("*** Provide your Access Key ***", "*** Provide your Secret Key ***", "https://your-endpoint");
//List versioning objects.
try
{
    ListVersionsRequest request = new ListVersionsRequest();
    request.BucketName = "bucketname";
    ListVersionsResponse response = client.ListVersions(request);
    foreach (ObsObjectVersion objectVersion in response.Versions)
    {
        Console.WriteLine("Key: {0}", objectVersion.ObjectKey);
        Console.WriteLine("VersionId: {0}", objectVersion.VersionId);
    }
    Console.WriteLine("List versions response: {0}", response.StatusCode);
}
catch (ObsException ex)
{
    Console.WriteLine("ErrorCode: {0}", ex.ErrorCode);
    Console.WriteLine("ErrorMessage: {0}", ex.ErrorMessage);
}

Information about a maximum of 1000 versioning objects can be listed each time. If a bucket contains more than 1000 objects and ListVersionsResponse.IsTruncated is true in the returned result, not all versioning objects are listed. In such cases, you can use ListVersionsResponse.NextKeyMarker and ListVersionsResponse.NextVersionIdMarker to obtain the start position for next listing.

Listing Versioning Objects by Specifying the Number

Sample code:

// Create an instance of ObsClient.
ObsClient client = new ObsClient("*** Provide your Access Key ***", "*** Provide your Secret Key ***", "https://your-endpoint");
//List versioning objects by specifying the number.
try
{
    ListVersionsRequest request = new ListVersionsRequest();
    request.BucketName = "bucketname";
    request.MaxKeys = 100;
    ListVersionsResponse response = client.ListVersions(request);
    foreach (ObsObjectVersion objectVersion in response.Versions)
    {
        Console.WriteLine("Key: {0}", objectVersion.ObjectKey);
        Console.WriteLine("VersionId: {0}", objectVersion.VersionId);
    }
    Console.WriteLine("List versions response: {0}", response.StatusCode);
}
catch (ObsException ex)
{
    Console.WriteLine("ErrorCode: {0}", ex.ErrorCode);
    Console.WriteLine("ErrorMessage: {0}", ex.ErrorMessage);
}

Listing Versioning Objects by Specifying a Prefix

Sample code:

// Create an instance of ObsClient.
ObsClient client = new ObsClient("*** Provide your Access Key ***", "*** Provide your Secret Key ***", "https://your-endpoint");
//List versioning objects by specifying a prefix.
try
{
    ListVersionsRequest request = new ListVersionsRequest();
    request.BucketName = "bucketname";
    request.MaxKeys = 100;
    request.Prefix = "prefix";
    ListVersionsResponse response = client.ListVersions(request);
    foreach (ObsObjectVersion objectVersion in response.Versions)
    {
        Console.WriteLine("Key: {0}", objectVersion.ObjectKey);
        Console.WriteLine("VersionId: {0}", objectVersion.VersionId);
    }
    Console.WriteLine("List versions response: {0}", response.StatusCode);
}
catch (ObsException ex)
{
    Console.WriteLine("ErrorCode: {0}", ex.ErrorCode);
    Console.WriteLine("ErrorMessage: {0}", ex.ErrorMessage);
}

Listing Versioning Objects by Specifying the Start Position

Sample code:

// Create an instance of ObsClient.
ObsClient client = new ObsClient("*** Provide your Access Key ***", "*** Provide your Secret Key ***", "https://your-endpoint");
//Specify the start position for listing.
try
{
    ListVersionsRequest request = new ListVersionsRequest();
    request.BucketName = "bucketname";
    request.MaxKeys = 100;
    request.Prefix = "prefix";
    request.KeyMarker = "keyMarker";
    ListVersionsResponse response = client.ListVersions(request);
    foreach (ObsObjectVersion objectVersion in response.Versions)
    {
        Console.WriteLine("Key: {0}", objectVersion.ObjectKey);
        Console.WriteLine("VersionId: {0}", objectVersion.VersionId);
    }
    Console.WriteLine("List versions response: {0}", response.StatusCode);
}
catch (ObsException ex)
{
    Console.WriteLine("ErrorCode: {0}", ex.ErrorCode);
    Console.WriteLine("ErrorMessage: {0}", ex.ErrorMessage);
}

Listing All Versioning Objects in Paging Mode

Sample code:

// Create an instance of ObsClient.
ObsClient client = new ObsClient("*** Provide your Access Key ***", "*** Provide your Secret Key ***", "https://your-endpoint");
//List all versioning objects in paging mode.
try
{
    ListVersionsRequest request = new ListVersionsRequest();
    request.BucketName = "bucketname";
    request.MaxKeys = 100;
    ListVersionsResponse response;
    do
    {
        response = client.ListVersions(request);
        Console.WriteLine("List versions response: {0}", response.StatusCode);
        foreach (ObsObjectVersion objectVersion in response.Versions)
        {
            Console.WriteLine("Key: {0}", objectVersion.ObjectKey);
            Console.WriteLine("VersionId: {0}", objectVersion.VersionId);
        }
        request.KeyMarker = response.NextKeyMarker;
        request.VersionIdMarker = response.NextVersionIdMarker;
    }
    while (response.IsTruncated);
}
catch (ObsException ex)
{
    Console.WriteLine("ErrorCode: {0}", ex.ErrorCode);
    Console.WriteLine("ErrorMessage: {0}", ex.ErrorMessage);
}

Listing All Versioning Objects in a Folder

There is no folder concept in OBS. All elements in buckets are objects. Folders are actually objects whose sizes are 0 and whose names end with a slash (/). When you set a folder name as the prefix, objects in this folder will be listed. Sample code is as follows:

// Create an instance of ObsClient.
ObsClient client = new ObsClient("*** Provide your Access Key ***", "*** Provide your Secret Key ***", "https://your-endpoint");
//List all versioning objects in paging mode.
try
{
    ListVersionsRequest request = new ListVersionsRequest();
    request.BucketName = "bucketname";
    request.MaxKeys = 1000;
    // Set the prefix to dir/.
    request.Prefix = "dir/";
    ListVersionsResponse response;
    do
    {
        response = client.ListVersions(request);
        Console.WriteLine("List versions response: {0}", response.StatusCode);
        foreach (ObsObjectVersion objectVersion in response.Versions)
        {
            Console.WriteLine("Key: {0}", objectVersion.ObjectKey);
            Console.WriteLine("VersionId: {0}", objectVersion.VersionId);
        }
        request.KeyMarker = response.NextKeyMarker;
        request.VersionIdMarker = response.NextVersionIdMarker;
    }
    while (response.IsTruncated);
}
catch (ObsException ex)
{
    Console.WriteLine("ErrorCode: {0}", ex.ErrorCode);
    Console.WriteLine("ErrorMessage: {0}", ex.ErrorMessage);
}
Parent topic: Versioning Management