Listing Versioning Objects

You can call OBSListObjectsVersionsRequest to list versioning objects in a bucket.

The following table describes the parameters involved in this API.

• If the value of versionIDMarker is not a version ID specified by keyMarker, versionIDMarker is invalid.
• The returned result of OBSListObjectsVersionsRequest includes the versioning objects and delete markers.

static OBSClient *client;
NSString *endPoint = @"your-endpoint";
// Hard-coded or plaintext AK/SK are risky. For security purposes, encrypt your AK/SK and store them in the configuration file or environment variables. In this example, the AK/SK are stored in environment variables for identity authentication. Before running this example, configure environment variables AccessKeyID and SecretAccessKey.
// Obtain an AK/SK pair on the management console. For details, see https://support.huaweicloud.com/intl/en-us/usermanual-ca/ca_01_0003.html.
char* ak_env = getenv("AccessKeyID");
char* sk_env = getenv("SecretAccessKey");
NSString *AK = [NSString stringWithUTF8String:ak_env];
NSString *SK = [NSString stringWithUTF8String:sk_env];
    
// Initialize identity authentication.
 OBSStaticCredentialProvider *credentialProvider = [[OBSStaticCredentialProvider alloc] initWithAccessKey:AK secretKey:SK];
   
//Initialize service configuration.
OBSServiceConfiguration *conf = [[OBSServiceConfiguration alloc] initWithURLString:endPoint credentialProvider:credentialProvider];
    
// Initialize an instance of OBSClient.
client = [[OBSClient alloc] initWithConfiguration:conf];
    
//List versioning objects.
OBSListObjectsVersionsRequest *request = [[OBSListObjectsVersionsRequest alloc] initWithBucketName:@"bucketname"];
    
[client listObjectsVersions:request completionHandler:^(OBSListObjectsVersionsResponse *response, NSError *error) {
     for (int i =0; i<response.versionList.count; i++) {
        NSLog(@"%@ \n",response.versionList[i].key);
    }
 }];

• Information about a maximum of 1000 versioning objects can be listed each time. If a bucket contains more than 1000 objects and response.isTruncated is YES in the returned result, not all versioning objects are listed. In such cases, you can use response.nextKeyMarker and response.versionIdMarker to obtain the start position for next listing.
• If you want to obtain all versioning objects in a specified bucket, you can use the paging mode for listing objects.

static OBSClient *client;
NSString *endPoint = @"your-endpoint";
// Hard-coded or plaintext AK/SK are risky. For security purposes, encrypt your AK/SK and store them in the configuration file or environment variables. In this example, the AK/SK are stored in environment variables for identity authentication. Before running this example, configure environment variables AccessKeyID and SecretAccessKey.
// Obtain an AK/SK pair on the management console. For details, see https://support.huaweicloud.com/intl/en-us/usermanual-ca/ca_01_0003.html.
char* ak_env = getenv("AccessKeyID");
char* sk_env = getenv("SecretAccessKey");
NSString *AK = [NSString stringWithUTF8String:ak_env];
NSString *SK = [NSString stringWithUTF8String:sk_env];
    
// Initialize identity authentication.
OBSStaticCredentialProvider *credentialProvider = [[OBSStaticCredentialProvider alloc] initWithAccessKey:AK secretKey:SK];
    
//Initialize service configuration.
OBSServiceConfiguration *conf = [[OBSServiceConfiguration alloc] initWithURLString:endPoint credentialProvider:credentialProvider];
    
// Initialize an instance of OBSClient.
client = [[OBSClient alloc] initWithConfiguration:conf];
    
// List versioning objects.
OBSListObjectsVersionsRequest *request = [[OBSListObjectsVersionsRequest alloc] initWithBucketName:@"bucketname"];
    
// Set the number of versioning objects to be listed to 100.
request.maxKeys = [NSNumber numberWithInt:100];
    
    
[client listObjectsVersions:request completionHandler:^(OBSListObjectsVersionsResponse *response, NSError *error) {
     for (int i =0; i<response.versionList.count; i++) {
        NSLog(@"%@ \n",response.versionList[i].key);
   }
}];

static OBSClient *client;
NSString *endPoint = @"your-endpoint";
// Hard-coded or plaintext AK/SK are risky. For security purposes, encrypt your AK/SK and store them in the configuration file or environment variables. In this example, the AK/SK are stored in environment variables for identity authentication. Before running this example, configure environment variables AccessKeyID and SecretAccessKey.
// Obtain an AK/SK pair on the management console. For details, see https://support.huaweicloud.com/intl/en-us/usermanual-ca/ca_01_0003.html.
char* ak_env = getenv("AccessKeyID");
char* sk_env = getenv("SecretAccessKey");
NSString *AK = [NSString stringWithUTF8String:ak_env];
NSString *SK = [NSString stringWithUTF8String:sk_env];
    
// Initialize identity authentication.
OBSStaticCredentialProvider *credentialProvider = [[OBSStaticCredentialProvider alloc] initWithAccessKey:AK secretKey:SK];
    
//Initialize service configuration.
OBSServiceConfiguration *conf = [[OBSServiceConfiguration alloc] initWithURLString:endPoint credentialProvider:credentialProvider];
    
// Initialize an instance of OBSClient.
client = [[OBSClient alloc] initWithConfiguration:conf];
    
// List versioning objects.
OBSListObjectsVersionsRequest *request = [[OBSListObjectsVersionsRequest alloc] initWithBucketName:@"bucketname"];
    
// Set the prefix.
request.prefix = @"/";
    
[client listObjectsVersions:request completionHandler:^(OBSListObjectsVersionsResponse *response, NSError *error) {
     for (int i =0; i<response.versionList.count; i++) {
        NSLog(@"%@ \n",response.versionList[i].key);
    }
        
}];

static OBSClient *client;
NSString *endPoint = @"your-endpoint";
// Hard-coded or plaintext AK/SK are risky. For security purposes, encrypt your AK/SK and store them in the configuration file or environment variables. In this example, the AK/SK are stored in environment variables for identity authentication. Before running this example, configure environment variables AccessKeyID and SecretAccessKey.
// Obtain an AK/SK pair on the management console. For details, see https://support.huaweicloud.com/intl/en-us/usermanual-ca/ca_01_0003.html.
char* ak_env = getenv("AccessKeyID");
char* sk_env = getenv("SecretAccessKey");
NSString *AK = [NSString stringWithUTF8String:ak_env];
NSString *SK = [NSString stringWithUTF8String:sk_env];
    
// Initialize identity authentication.
OBSStaticCredentialProvider *credentialProvider = [[OBSStaticCredentialProvider alloc] initWithAccessKey:AK secretKey:SK];
    
//Initialize service configuration.
OBSServiceConfiguration *conf = [[OBSServiceConfiguration alloc] initWithURLString:endPoint credentialProvider:credentialProvider];
    
// Initialize an instance of OBSClient.
client = [[OBSClient alloc] initWithConfiguration:conf];
    
// List versioning objects.
OBSListObjectsVersionsRequest *request = [[OBSListObjectsVersionsRequest alloc] initWithBucketName:@"bucketname"];
    
// Specify the start position for listing.
request.keyMarker = @"/";
    
[client listObjectsVersions:request completionHandler:^(OBSListObjectsVersionsResponse *response, NSError *error) {
     for (int i =0; i<response.versionList.count; i++) {
        NSLog(@"%@ \n",response.versionList[i].key);
    }
}];

static OBSClient *client;
NSString *endPoint = @"your-endpoint";
// Hard-coded or plaintext AK/SK are risky. For security purposes, encrypt your AK/SK and store them in the configuration file or environment variables. In this example, the AK/SK are stored in environment variables for identity authentication. Before running this example, configure environment variables AccessKeyID and SecretAccessKey.
// Obtain an AK/SK pair on the management console. For details, see https://support.huaweicloud.com/intl/en-us/usermanual-ca/ca_01_0003.html.
char* ak_env = getenv("AccessKeyID");
char* sk_env = getenv("SecretAccessKey");
NSString *AK = [NSString stringWithUTF8String:ak_env];
NSString *SK = [NSString stringWithUTF8String:sk_env];
    
// Initialize identity authentication.
OBSStaticCredentialProvider *credentialProvider = [[OBSStaticCredentialProvider alloc] initWithAccessKey:AK secretKey:SK];
    
//Initialize service configuration.
OBSServiceConfiguration *conf = [[OBSServiceConfiguration alloc] initWithURLString:endPoint credentialProvider:credentialProvider];
    
// Initialize an instance of OBSClient.
client = [[OBSClient alloc] initWithConfiguration:conf];
    
// List versioning objects.
    
__block OBSListObjectsVersionsResponse *result;
    
    // List objects.
OBSListObjectsVersionsRequest *request = [[OBSListObjectsVersionsRequest alloc] initWithBucketName:@"bucketname"];
    
request.maxKeys = [NSNumber numberWithInt:1];
// List all versioning objects.
do {
    dispatch_semaphore_t sema = dispatch_semaphore_create(0);
    [client listObjectsVersions:request completionHandler:^(OBSListObjectsVersionsResponse *response, NSError *error) {
        result = response;
     for (int i =0; i<response.versionList.count; i++) {
        NSLog(@"%@ \n",response.versionList[i].key);
    }
        request.keyMarker = result.nextKeyMarker;
        dispatch_semaphore_signal(sema);
   }];
   dispatch_semaphore_wait(sema, DISPATCH_TIME_FOREVER);
} while (result.isTruncated);

static OBSClient *client;
NSString *endPoint = @"your-endpoint";
// Hard-coded or plaintext AK/SK are risky. For security purposes, encrypt your AK/SK and store them in the configuration file or environment variables. In this example, the AK/SK are stored in environment variables for identity authentication. Before running this example, configure environment variables AccessKeyID and SecretAccessKey.
// Obtain an AK/SK pair on the management console. For details, see https://support.huaweicloud.com/intl/en-us/usermanual-ca/ca_01_0003.html.
char* ak_env = getenv("AccessKeyID");
char* sk_env = getenv("SecretAccessKey");
NSString *AK = [NSString stringWithUTF8String:ak_env];
NSString *SK = [NSString stringWithUTF8String:sk_env];
    
// Initialize identity authentication.
OBSStaticCredentialProvider *credentialProvider = [[OBSStaticCredentialProvider alloc] initWithAccessKey:AK secretKey:SK];
    
//Initialize service configuration.
OBSServiceConfiguration *conf = [[OBSServiceConfiguration alloc] initWithURLString:endPoint credentialProvider:credentialProvider];
    
// Initialize an instance of OBSClient.
client = [[OBSClient alloc] initWithConfiguration:conf];
    
// List versioning objects.
    
__block OBSListObjectsVersionsResponse *result;
    
// List objects.
OBSListObjectsVersionsRequest *request = [[OBSListObjectsVersionsRequest alloc] initWithBucketName:@"bucketname"];
    
request.delimiter = @"/";
// Objects in the root directory
[client listObjectsVersions:request completionHandler:^(OBSListObjectsVersionsResponse *response, NSError *error) {
        
    for (int i =0; i<response.versionList.count; i++) {
        NSLog(@"%@ \n",response.versionList[i].key);
    }
    [self listVersionObjectsByPrefix:client request:request result:response];
}];

listVersionObjectsByPrefix function:

-(void) listVersionObjectsByPrefix:(OBSClient*) client request:(OBSListObjectsVersionsRequest *) request result:            (OBSListObjectsVersionsResponse*) result{
    
    for (NSString * prefix in result.commonPrefixesList){
        NSLog(@"Objects in folder [%@]:",prefix);
        request.prefix = prefix;
        [client listObjectsVersions:request completionHandler:^(OBSListObjectsVersionsResponse *response, NSError *error) {
            for (int i =0; i<response.versionList.count; i++) {
                NSLog(@"%@ \n",response.versionList[i].key);
            }
            [self listVersionObjectsByPrefix:client request:request result:response];
        }];
    }
    
}

• The previous sample code does not include scenarios where the number of objects in a folder exceeds 1000.
• Because objects and sub-folders in a folder are to be listed and all the object names end with a slash (/), delimiter is always a slash (/).
• In the returned result of each recursion, ListVersionsResult.getVersions includes the versioning objects in the folder and ListVersionsResult.getCommonPrefixes includes the sub-folders in the folder.