Object management

Upload Object

Simplest upload

• Basic workflow

  1. Instantiate the BOSClient class.
  2. Use the BOSClient putObject method to upload objects either as files or binary strings.
  3. For the returned instance of type BOSPutObjectResponse, you can retrieve the eTag.

• Example code

  Swift Copy

  1BOSObjectContent* content = [[BOSObjectContent alloc] init];
  2// In file mode
  3content.objectData.file = @"<file path>";
  4// Or in binary data mode
  5NSData* data = [[NSData alloc] init];
  6content.objectData.data = data;
  7BOSPutObjectRequest* request = [[BOSPutObjectRequest alloc] init];
  8request.bucket = @"<bucketname>";
  9request.key = @"<objectname>";
  10request.objectContent = content;
  11__block BOSPutObjectResponse* response = nil;
  12BCETask* task = [client putObject:request];
  13task.then(^(BCEOutput* output) {
  14  if (output.progress) {
  15      NSLog(@"put object progress is %@", output.progress);
  16  }
  17  if (output.response) {
  18      response = (BOSPutObjectResponse*)output.response;
  19      NSLog(@"put object success!");
  20  }
  21  if (output.error) {
  22      NSLog(@"put object failure");
  23  }
  24});
  25[task waitUtilFinished];

  Plain Text Copy

  1> **Note**: Objects are uploaded to BOS as files, and the putObject function supports uploading objects with a size not exceeding 5GB. After the putObject request is processed successfully, BOS will return the ETag of the object in the Header as the file identifier.

• Complete example

  Swift Copy

  1#import <BaiduBCEBasic/BaiduBCEBasic.h>
  2#import <BaiduBCEBOS/BaiduBCEBOS.h>
  3void example(void) {
  4// Initialize
  5    BCECredentials* credentials = [[BCECredentials alloc] init];
  6    credentials.accessKey = @"<access key>";
  7    credentials.secretKey = @"<secret key>";
  8    BOSClientConfiguration* configuration = [[BOSClientConfiguration alloc] init];
  9    configuration.credentials = credentials;
  10    BOSClient* client = [[BOSClient alloc] initWithConfiguration:configuration];
  11    BOSObjectContent* content = [[BOSObjectContent alloc] init];
  12// In file mode
  13    content.objectData.file = @"<file path>";
  14// Or in binary data mode
  15    NSData* data = [[NSData alloc] init];
  16    content.objectData.data = data;
  17    BOSPutObjectRequest* request = [[BOSPutObjectRequest alloc] init];
  18    request.bucket = @"<bucketname>";
  19    request.key = @"<objectname>";
  20    request.objectContent = content;
  21    __block BOSPutObjectResponse* response = nil;
  22    BCETask* task = [client putObject:request];
  23    task.then(^(BCEOutput* output) {
  24        if (output.progress) {
  25            NSLog(@"put object progress is %@", output.progress);
  26        }
  27        if (output.response) {
  28            response = (BOSPutObjectResponse*)output.response;
  29            NSLog(@"put object success!");
  30        }
  31        if (output.error) {
  32            NSLog(@"put object failure");
  33        }
  34    });
  35    [task waitUtilFinished];
  36}

Set object's HTTP Header

BOS allows setting Http Headers when uploading an object.

• Basic workflow

  1. Create a BOSObjectMetadata class instance.
  2. Set fields like contentEncoding, contentType, and contentDisposition in the BOSObjectMetadata instance.
  3. Assign the BOSObjectMetadata instance to the objectContent.metadata field of the BOSPutObjectRequest.

• Example code

  Swift Copy

  1BOSObjectMetadata* metadata = [[BOSObjectMetadata alloc] init];
  2metadata.contentEncoding = @"<encoding>";
  3metadata.contentDisposition = @"<content disposition>";
  4content.metadata = metadata;

• Complete example

  Swift Copy

  1#import <BaiduBCEBasic/BaiduBCEBasic.h>
  2#import <BaiduBCEBOS/BaiduBCEBOS.h>
  3void example(void) {
  4// Initialize
  5    BCECredentials* credentials = [[BCECredentials alloc] init];
  6    credentials.accessKey = @"<access key>";
  7    credentials.secretKey = @"<secret key>";
  8    BOSClientConfiguration* configuration = [[BOSClientConfiguration alloc] init];
  9    configuration.credentials = credentials;
  10    BOSClient* client = [[BOSClient alloc] initWithConfiguration:configuration];
  11    BOSObjectContent* content = [[BOSObjectContent alloc] init];
  12// In file mode
  13    content.objectData.file = @"<file path>";
  14// Or in binary data mode
  15    NSData* data = [[NSData alloc] init];
  16    content.objectData.data = data;
  17    BOSObjectMetadata* metadata = [[BOSObjectMetadata alloc] init];
  18    metadata.contentEncoding = @"<encoding>";
  19    metadata.contentDisposition = @"<content disposition>";
  20    content.metadata = metadata;
  21    BOSPutObjectRequest* request = [[BOSPutObjectRequest alloc] init];
  22    request.bucket = @"<bucketname>";
  23    request.key = @"<Objectname>";
  24    request.objectContent = content;
  25    __block BOSPutObjectResponse* response = nil;
  26    BCETask* task = [client putObject:request];
  27    task.then(^(BCEOutput* output) {
  28        if (output.progress) {
  29            NSLog(@"put object progress is %@", output.progress);
  30        }
  31        if (output.response) {
  32            response = (BOSPutObjectResponse*)output.response;
  33            NSLog(@"put object success!");
  34        }
  35        if (output.error) {
  36            NSLog(@"put object failure");
  37        }
  38    });
  39    [task waitUtilFinished];
  40}

User-defined metadata

BOS supports user-defined metadata for object descriptions.

• Basic workflow

  1. Create a BOSObjectMetadata class instance.
  2. Assign a custom metadata dictionary to the userMetadata field of the BOSObjectMetadata.

• Example code

  Swift Copy

  1BOSObjectMetadata* metadata = [[BOSObjectMetadata alloc] init];
  2metadata.contentEncoding = @"<encoding>";
  3metadata.contentDisposition = @"<content disposition>";
  4content.metadata = metadata;
  5NSDictionary* customMetadata = @{
  6  @"name" : @"my-data"
  7};
  8content.metadata.userMetadata = customMetadata;

  Plain Text Copy

  1> **Note:** In the provided example, a user-defined metadata property is created with the key "name" and the value "my-data." This metadata can be retrieved when the object is downloaded. Though multiple such parameters can be added, the combined size of all User Metadata must not exceed 2KB.  

• Complete example

  Swift Copy

  1#import <BaiduBCEBasic/BaiduBCEBasic.h>
  2#import <BaiduBCEBOS/BaiduBCEBOS.h>
  3void example(void) {
  4// Initialize
  5    BCECredentials* credentials = [[BCECredentials alloc] init];
  6    credentials.accessKey = @"<access key>";
  7    credentials.secretKey = @"<secret key>";
  8    BOSClientConfiguration* configuration = [[BOSClientConfiguration alloc] init];
  9    configuration.credentials = credentials;
  10    BOSClient* client = [[BOSClient alloc] initWithConfiguration:configuration];
  11    BOSObjectContent* content = [[BOSObjectContent alloc] init];
  12// In file mode
  13    content.objectData.file = @"<file path>";
  14// Or in binary data mode
  15    NSData* data = [[NSData alloc] init];
  16    content.objectData.data = data;
  17    BOSObjectMetadata* metadata = [[BOSObjectMetadata alloc] init];
  18    metadata.contentEncoding = @"<encoding>";
  19    metadata.contentDisposition = @"<content disposition>";
  20    content.metadata = metadata;
  21    NSDictionary* customMetadata = @{
  22        @"name" : @"my-data"
  23    };
  24    content.metadata.userMetadata = customMetadata;
  25    BOSPutObjectRequest* request = [[BOSPutObjectRequest alloc] init];
  26    request.bucket = @"<bucketname>";
  27    request.key = @"<objectname>";
  28    request.objectContent = content;
  29    __block BOSPutObjectResponse* response = nil;
  30    BCETask* task = [client putObject:request];
  31    task.then(^(BCEOutput* output) {
  32        if (output.progress) {
  33            NSLog(@"put object progress is %@", output.progress);
  34        }
  35        if (output.response) {
  36            response = (BOSPutObjectResponse*)output.response;
  37            NSLog(@"put object success!");
  38        }
  39        if (output.error) {
  40            NSLog(@"put object failure");
  41        }
  42    });
  43    [task waitUtilFinished];
  44}

View the object in the bucket.

Simple query

View the list of objects in a bucket.

• Basic workflow

  1. Instantiate the BOSClient class.
  2. Executing the BOSClient listObjects method will return an instance of the BOSListObjectsResponse class.
  3. You can iterate through the contents field of the BOSListObjectsResponse type to retrieve keys, lastModified dates, eTags, sizes, and owners.

• Example code

  Swift Copy

  1BOSListObjectsRequest* listObjRequest = [[BOSListObjectsRequest alloc] init];
  2listObjRequest.bucket = @"<bucketname>";
  3__block BOSListObjectsResponse* listObjResponse = nil;
  4BCETask* task = [client listObjects:listObjRequest];
  5task.then(^(BCEOutput* output) {
  6  if (output.response) {
  7      listObjResponse = (BOSListObjectsResponse*)output.response;
  8      for (BOSObjectInfo* object in listObjResponse.contents) {
  9          NSLog(@"the object key is %@", object.key);
  10          NSLog(@"the object lastModified is %@", object.lastModified);
  11          NSLog(@"the object eTag is %@", object.eTag);
  12          NSLog(@"the object size is %llu", object.size);
  13          NSLog(@"the object owner id is %@", object.owner.ownerID);
  14      }
  15  }
  16  if (output.error) {
  17      NSLog(@"list objects failure");
  18  }
  19});
  20[task waitUtilFinished];

  Plain Text Copy

  1> **Note:** The listObjects method returns a BOSListObjectsResponse object, which contains the results of this listObject request. Users can obtain the description information of all objects through the contents attribute in BOSListObjectsResponse.
  2>
  3> -   By default, if the number of objects in a bucket exceeds 1,000, only 1,000 objects will be returned. The isTruncated value in the result will be YES, and nextMarker will indicate the starting point for the next query.  
  4> -   To retrieve more objects, use the marker parameter for reading in batches. Refer to [Extended Query](#Extended query).

• Complete example

  Swift Copy

  1#import <BaiduBCEBasic/BaiduBCEBasic.h>
  2#import <BaiduBCEBOS/BaiduBCEBOS.h>
  3void example(void) {
  4 // Initialize
  5    BCECredentials* credentials = [[BCECredentials alloc] init];
  6    credentials.accessKey = @"<access key>";
  7    credentials.secretKey = @"<secret key>";
  8    BOSClientConfiguration* configuration = [[BOSClientConfiguration alloc] init];
  9    configuration.credentials = credentials;
  10    BOSClient* client = [[BOSClient alloc] initWithConfiguration:configuration];
  11    BOSListObjectsRequest* listObjRequest = [[BOSListObjectsRequest alloc] init];
  12    listObjRequest.bucket = @"<bucketname>";
  13    __block BOSListObjectsResponse* listObjResponse = nil;
  14    BCETask* task = [client listObjects:listObjRequest];
  15    task.then(^(BCEOutput* output) {
  16        if (output.response) {
  17            listObjResponse = (BOSListObjectsResponse*)output.response;
  18            for (BOSObjectInfo* object in listObjResponse.contents) {
  19                NSLog(@"the object key is %@", object.key);
  20                NSLog(@"the object lastModified is %@", object.lastModified);
  21                NSLog(@"the object eTag is %@", object.eTag);
  22                NSLog(@"the object size is %llu", object.size);
  23                NSLog(@"the object owner id is %@", object.owner.ownerID);
  24            }
  25        }
  26        if (output.error) {
  27            NSLog(@"list objects failure");
  28        }
  29    });
  30    [task waitUtilFinished];
  31}

Extended query

Users can configure BOSListObjectsRequest parameters to enable additional query operations. The available extended parameters in BOSListObjectsRequest include:

• Basic workflow

  1. Create a BOSListObjectsRequest class instance.
  2. Configure fields like delimiter, marker, prefix, and maxKeys in the BOSListObjectsRequest to enable extended query operations.
  3. Create a BOSClient instance and execute the listObjects method.

• Example code

  Swift Copy

  1BOSListObjectsRequest* listObjRequest = [[BOSListObjectsRequest alloc] init];
  2listObjRequest.bucket = @"<bucketname>";
  3listObjRequest.marker = @"<marker>";
  4__block BOSListObjectsResponse* listObjResponse = nil;
  5BCETask* task = [client listObjects:listObjRequest];
  6task.then(^(BCEOutput* output) {
  7  if (output.response) {
  8      listObjResponse = (BOSListObjectsResponse*)output.response;
  9      for (BOSObjectInfo* object in listObjResponse.contents) {
  10          NSLog(@"the object key is %@", object.key);
  11          NSLog(@"the object lastModified is %@", object.lastModified);
  12          NSLog(@"the object eTag is %@", object.eTag);
  13          NSLog(@"the object size is %llu", object.size);
  14          NSLog(@"the object owner id is %@", object.owner.ownerID);
  15      }
  16  }
  17  if (output.error) {
  18      NSLog(@"list objects failure");
  19  }
  20});
  21[task waitUtilFinished];

• Complete example

  Example 1:

  Swift Copy

  1#import <BaiduBCEBasic/BaiduBCEBasic.h>
  2#import <BaiduBCEBOS/BaiduBCEBOS.h>
  3void example(void) {
  4 // Initialize
  5    BCECredentials* credentials = [[BCECredentials alloc] init];
  6    credentials.accessKey = @"<access key>";
  7    credentials.secretKey = @"<secret key>";
  8    BOSClientConfiguration* configuration = [[BOSClientConfiguration alloc] init];
  9    configuration.credentials = credentials;
  10    BOSClient* client = [[BOSClient alloc] initWithConfiguration:configuration];
  11    BOSListObjectsRequest* listObjRequest = [[BOSListObjectsRequest alloc] init];
  12    listObjRequest.bucket = @"<bucketname>";
  13    listObjRequest.marker = @"<marker>";
  14    __block BOSListObjectsResponse* listObjResponse = nil;
  15    BCETask* task = [client listObjects:listObjRequest];
  16    task.then(^(BCEOutput* output) {
  17        if (output.response) {
  18            listObjResponse = (BOSListObjectsResponse*)output.response;
  19            for (BOSObjectInfo* object in listObjResponse.contents) {
  20                NSLog(@"the object key is %@", object.key);
  21                NSLog(@"the object lastModified is %@", object.lastModified);
  22                NSLog(@"the object eTag is %@", object.eTag);
  23                NSLog(@"the object size is %llu", object.size);
  24                NSLog(@"the object owner id is %@", object.owner.ownerID);
  25            }
  26        }
  27        if (output.error) {
  28            NSLog(@"list objects failure");
  29        }
  30    });
  31    [task waitUtilFinished];
  32}

  Example II: A complete example using nextMarker.

  Swift Copy

  1#import <BaiduBCEBasic/BaiduBCEBasic.h>
  2#import <BaiduBCEBOS/BaiduBCEBOS.h>
  3void example(void) {
  4 // Initialize
  5    BCECredentials* credentials = [[BCECredentials alloc] init];
  6    credentials.accessKey = @"<access key>";
  7    credentials.secretKey = @"<secret key>";
  8    BOSClientConfiguration* configuration = [[BOSClientConfiguration alloc] init];
  9    configuration.credentials = credentials;
  10    BOSClient* client = [[BOSClient alloc] initWithConfiguration:configuration];
  11    BOSListObjectsRequest* listObjRequest = [[BOSListObjectsRequest alloc] init];
  12    listObjRequest.bucket = @"<bucketname>";
  13    listObjRequest.marker = @"<marker>";
  14    __block BOSListObjectsResponse* listObjResponse = nil;
  15    BCETask* task = [client listObjects:listObjRequest];
  16    task.then(^(BCEOutput* output) {
  17        if (output.response) {
  18            listObjResponse = (BOSListObjectsResponse*)output.response;
  19        }
  20        if (output.error) {
  21            NSLog(@"list objects failure");
  22        }
  23    });
  24    [task waitUtilFinished];
  25    if (listObjResponse != nil) {
  26        listObjRequest.marker = listObjResponse.nextMarker;
  27        task = [client listObjects:listObjRequest];
  28        task.then(^(BCEOutput* output) {
  29            if (output.response) {
  30                listObjResponse = (BOSListObjectsResponse*)output.response;
  31                for (BOSObjectInfo* object in listObjResponse.contents) {
  32                    NSLog(@"the object key is %@", object.key);
  33                    NSLog(@"the object lastModified is %@", object.lastModified);
  34                    NSLog(@"the object eTag is %@", object.eTag);
  35                    NSLog(@"the object size is %llu", object.size);
  36                    NSLog(@"the object owner id is %@", object.owner.ownerID);
  37                }
  38            }
  39        });
  40    }
  41}

Query simulated folders

Since BOS is inherently a (<Key>,<Value>) storage system, the concept of "folder" does not exist in principle. However, you can simulate the folder function by combining the delimiter and prefix} parameters.

Suppose the bucket contains five files: bos.jpg, fun/, fun/test.jpg, fun/movie/001.avi, and fun/movie/007.avi. The "/" symbol can be used as a delimiter to mimic folder structures.

Recursively list all files under the simulated folder

You can obtain all files under a simulated folder by setting the prefix parameter:

1BOSListObjectsRequest* listObjRequest = [[BOSListObjectsRequest alloc] init];
2listObjRequest.bucket = @"<bucketname>";
3 listObjRequest.prefix = @"fun/";
4__block BOSListObjectsResponse* listObjResponse = nil;
5BCETask* task = [client listObjects:listObjRequest];
6task.then(^(BCEOutput* output) {
7    if (output.response) {
8        listObjResponse = (BOSListObjectsResponse*)output.response;
9        for (BOSObjectInfo* object in listObjResponse.contents) {
10            NSLog(@"%@", object.key);
11        }
12    }
13});
14[task waitUtilFinished];

Output:

1Objects:
2fun/
3fun/movie/001.avi
4fun/movie/007.avi
5fun/test.jpg

View files and subfolders under the simulated folder

With the combination of prefix and delimiter, it can list files and subfolders under the simulated folder:

1BOSListObjectsRequest* listObjRequest = [[BOSListObjectsRequest alloc] init];
2listObjRequest.bucket = @"<bucketname>";
3// Specify "/" as the delimiter for simulated folder
4listObjRequest.delimiter = @"/";
5// List all files and subfolders under the fun folder
6listObjRequest.prefix = @"fun/";
7__block BOSListObjectsResponse* listObjResponse = nil;
8BCETask* task = [client listObjects:listObjRequest];
9task.then(^(BCEOutput* output) {
10    if (output.response) {
11        listObjResponse = (BOSListObjectsResponse*)output.response;
12    }
13    if (output.error) {
14        NSLog(@"list objects failure");
15    }
16});
17[task waitUtilFinished];
18// Traverse all objects
19NSLog(@"Objects:");
20for (BOSObjectInfo* object in listObjResponse.contents) {
21    NSLog(@"%@", object.key);
22}
23// Traverse all CommonPrefixes
24NSLog(@"CommonPrefixs:");
25for (NSString* commonPrefix in listObjResponse.commonPrefixes) {
26    NSLog(@"%@", commonPrefix);
27}

Output:

1Objects:
2fun/
3fun/test.jpg
4CommonPrefixs:
5fun/movie/

Note: In the returned results, the list of contents shows the files under the “fun” folder. The list in commonPrefixs shows all subfolders under the fun folder. It can be seen that the two files fun/movie/001.avi and fun/movie/007.avi are not listed because they belong to the movie subfolder under the fun folder.

Get Object

Simple object get

You can load the object into memory using the provided code.

• Basic workflow

  1. Instantiate the BOSClient class.
  2. Executing the BOSClient getObject method will return a BOSGetObjectResponse instance.
  3. Access the objectContent.objectData.data property of the BOSGetObjectResponse instance to retrieve the data.

• Example code

  Swift Copy

  1__block BOSGetObjectResponse* getObjResponse = nil;
  2BOSGetObjectRequest* getObjRequest = [[BOSGetObjectRequest alloc] init];
  3getObjRequest.bucket = @"<bucketname>";
  4getObjRequest.key = @"<objectname>";
  5BCETask* task = [client getObject:getObjRequest];
  6task.then(^(BCEOutput* output) {
  7  if (output.response) {
  8      getObjResponse = (BOSGetObjectResponse*)output.response;
  9      NSLog(@"get object success!");
  10  }
  11  if (output.error) {
  12      NSLog(@"get object failure with %@", outpu****t.error);
  13  }
  14  if (output.progress) {
  15      NSLog(@"the get object progress is %@", output.progress);
  16  }
  17});
  18[task waitUtilFinished];
  19// Retrieve data from memory
  20NSData* data = getObjResponse.objectContent.objectData.data;

  Plain Text Copy

  1> **Note:**
  2>
  3> -   `BOSObjectContent` contains detailed information about the object, including its bucket location, object name, metadata, and data storage.  
  4> -   `BOSObjectMetadata` includes the ETag set during the object upload, HTTP headers, and custom metadata.  
  5> -   Retrieve the object's data through the `objectData` property of `BOSObjectContent`.  

• Complete example

  Swift Copy

  1#import <BaiduBCEBasic/BaiduBCEBasic.h>
  2#import <BaiduBCEBOS/BaiduBCEBOS.h>
  3void example(void) {
  4 // Initialize
  5    BCECredentials* credentials = [[BCECredentials alloc] init];
  6    credentials.accessKey = @"<access key>";
  7    credentials.secretKey = @"<secret key>";
  8    BOSClientConfiguration* configuration = [[BOSClientConfiguration alloc] init];
  9    configuration.credentials = credentials;
  10    BOSClient* client = [[BOSClient alloc] initWithConfiguration:configuration];
  11    __block BOSGetObjectResponse* getObjResponse = nil;
  12    BOSGetObjectRequest* getObjRequest = [[BOSGetObjectRequest alloc] init];
  13    getObjRequest.bucket = @"<bucketname>";
  14    getObjRequest.key = @"<objectname>";
  15    BCETask* task = [client getObject:getObjRequest];
  16    task.then(^(BCEOutput* output) {
  17        if (output.response) {
  18            getObjResponse = (BOSGetObjectResponse*)output.response;
  19            NSLog(@"get object success!");
  20        }
  21        if (output.error) {
  22            NSLog(@"get object failure with %@", output.error);
  23        }
  24        if (output.progress) {
  25            NSLog(@"the get object progress is %@", output.progress);
  26        }
  27    });
  28    [task waitUtilFinished];
  29    NSData* data = getObjResponse.objectContent.objectData.data;
  30}

Download part of the content of an object

• Basic workflow

  1. Instantiate the BOSGetObjectRequest class.
  2. Specify the rangeStart and/or rangeEnd fields in the BOSGetObjectRequest instance.
  3. Perform the client.getObject operation.

• Example code

  Swift Copy

  1__block BOSGetObjectResponse* getObjResponse = nil;
  2BOSGetObjectRequest* getObjRequest = [[BOSGetObjectRequest alloc] init];
  3getObjRequest.bucket = @"<bucketname>";
  4getObjRequest.key = @"<objectname>";
  5// Retrieve the first 100 bytes
  6getObjRequest.rangeStart = @"0";
  7getObjRequest.rangeEnd = @"99";
  8BCETask* task = [client getObject:getObjRequest];
  9task.then(^(BCEOutput* output) {
  10    if (output.response) {
  11        getObjResponse = (BOSGetObjectResponse*)output.response;
  12        NSLog(@"get object success!");
  13    }
  14    if (output.error) {
  15        NSLog(@"get object failure with %@", output.error);
  16    }
  17    if (output.progress) {
  18        NSLog(@"the get object progress is %@", output.progress);
  19    }
  20});
  21[task waitUtilFinished];
  22NSData* data = getObjResponse.objectContent.objectData.data;

  Plain Text Copy

  1> **Note:** Users can leverage this function for segmented downloads and resumable file uploads.  

Download object to a specified path

Users can use the following code to directly download an object to a specified path.

• Basic workflow

  1. Instantiate the BOSGetObjectRequest class.
  2. Specify the filename to be saved in the file field of the BOSGetObjectRequest instance.
  3. Perform the client.getObject operation.
  4. Download an object directly to a specified path.

• Example code

  Swift Copy

  1__block BOSGetObjectResponse* getObjResponse = nil;
  2BOSGetObjectRequest* getObjRequest = [[BOSGetObjectRequest alloc] init];
  3getObjRequest.bucket = @"<bucketname>";
  4getObjRequest.key = @"<objectname>";
  5// Set the file path for saving
  6getObjRequest.file = @"<file>";
  7BCETask* task = [client getObject:getObjRequest];
  8task.then(^(BCEOutput* output) {
  9    if (output.response) {
  10        getObjResponse = (BOSGetObjectResponse*)output.response;
  11        NSLog(@"get object success!");
  12    }
  13    if (output.error) {
  14        NSLog(@"get object failure with %@", output.error);
  15    }
  16    if (output.progress) {
  17        NSLog(@"the get object progress is %@", output.progress);
  18    }
  19});
  20[task waitUtilFinished];

Obtain the storageClass of an object

The storage class of an object is categorized into STANDARD (standard storage), STANDARD_IA (infrequent access storage), and COLD (cold storage).

Example code

1__block BOSGetObjectMetadataResponse* getObjMetaResponse = nil;
2BCETask* task = [client getObjectMetadata:@"<bucketname>" objectKey:@"<objectname>"];
3task.then(^(BCEOutput* output) {
4    if (output.response) {
5        getObjMetaResponse = (BOSGetObjectMetadataResponse*)output.response;
6        NSString storageClass = getObjMetaResponse.storageClass;
7        NSLog(@"get object storageClass success!");
8    }
9    if (output.error) {
10        NSLog(@"get object storageClass failure");
11    }
12});
13[task waitUtilFinished];

Obtain only ObjectMetadata

Use the getObjectMetadata method to retrieve only the object's metadata without including its content.

• Example code

  Swift Copy

  1__block BOSGetObjectMetadataResponse* getObjMetaResponse = nil;
  2BCETask* task = [client getObjectMetadata:@"<bucketname>" objectKey:@"<objectname>"];
  3task.then(^(BCEOutput* output) {
  4    if (output.response) {
  5        getObjMetaResponse = (BOSGetObjectMetadataResponse*)output.response;
  6        NSLog(@"get object metadata success!");
  7    }
  8    if (output.error) {
  9        NSLog(@"get object metadata failure");
  10    }
  11});
  12[task waitUtilFinished];

Get object URL

The following code allows you to get the URL of a specific object, which is commonly used for temporarily sharing the object's URL with others.

• Basic workflow

  1. Instantiate the BOSClient class.
  2. Execute the BOSClient.generatePresignedUrl method.
  3. The method returns the URL of the object.

• Example code

  Swift Copy

  1__block BOSGeneratePresignedUrlResponse *generateObjetUrlRes = nil;
  2  BCEOutput_ output = [client generatePresignedUrl:@"<bucketname>" objectKey:@"<objectname>" expirationInSeconds:<ExpirationInSeconds>];
  3  if (output.response) {
  4      generateObjetUrlRes = (BOSGeneratePresignedUrlResponse_)output.response;
  5      NSLog(@"get url success, the usrlstting is : %@", [generateObjetUrlRes.objectUrl absoluteString]);
  6  }
  7  if (output.error) {
  8      NSLog(@"get url failure, error : %@:", output.error);
  9  }

Note: ExpirationInSeconds is the specified URL validity period, calculated from the current time. It is an optional parameter, and the system default value is 1,800 seconds if not configured. To set a permanent non-expiration time, the ExpirationInSeconds parameter can be set to -1. You cannot set it to any other negative value.

• Complete example

  Swift Copy

  1#import <BaiduBCEBasic/BaiduBCEBasic.h>
  2#import <BaiduBCEBOS/BaiduBCEBOS.h>
  3void example(void) {
  4 // Initialize
  5    BCECredentials* credentials = [[BCECredentials alloc] init];
  6    credentials.accessKey = @"<access key>";
  7    credentials.secretKey = @"<secret key>";
  8    BOSClientConfiguration* configuration = [[BOSClientConfiguration alloc] init];
  9    configuration.credentials = credentials;
  10    BOSClient* client = [[BOSClient alloc] initWithConfiguration:configuration];
  11    __block BOSGeneratePresignedUrlResponse *generateObjetUrlRes = nil;
  12      BCEOutput* output = [client generatePresignedUrl:@"<bucketname>" objectKey:@"<objectname>" expirationInSeconds:<ExpirationInSeconds>];
  13    if (output.response) {
  14    generateObjetUrlRes = 	(BOSGeneratePresignedUrlResponse*)output.response;
  15    NSLog(@"get url success, the usrlstting is : %@", [generateObjetUrlRes.objectUrl absoluteString]);
  16    }
  17    if (output.error) {
  18    NSLog(@"get url failure, error : %@:", output.error);
  19    }
  20}

Delete Object

• Basic workflow

  1. Instantiate the BOSClient class.
  2. Call the eTag or lastModified method.
  3. Handle errors that arise after an operation fails.

• Example code

  Swift Copy

  1__block BOSDeleteObjectResponse* response = nil;
  2BCETask* task = [client deleteObject:@"<bucketname>" objectKey:@"<objectname>"];
  3task.then(^(BCEOutput* output) {
  4    if (output.response) {
  5        response = (BOSDeleteObjectResponse*)output.response;
  6        NSLog(@"delete obj success!");
  7    }
  8    if (output.error) {
  9        NSLog(@"delete obj failure");
  10    }
  11});
  12[task waitUtilFinished];

• Complete example

  Swift Copy

  1#import <BaiduBCEBasic/BaiduBCEBasic.h>
  2#import <BaiduBCEBOS/BaiduBCEBOS.h>
  3void example(void) {
  4 // Initialize
  5    BCECredentials* credentials = [[BCECredentials alloc] init];
  6    credentials.accessKey = @"<access key>";
  7    credentials.secretKey = @"<secret key>";
  8    BOSClientConfiguration* configuration = [[BOSClientConfiguration alloc] init];
  9    configuration.credentials = credentials;
  10    BOSClient* client = [[BOSClient alloc] initWithConfiguration:configuration];
  11    __block BOSDeleteObjectResponse* response = nil;
  12    BCETask* task = [client deleteObject:@"<bucketname>" objectKey:@"<objectname>"];
  13    task.then(^(BCEOutput* output) {
  14      if (output.response) {
  15          response = (BOSDeleteObjectResponse*)output.response;
  16          NSLog(@"delete obj success!");
  17      }
  18      if (output.error) {
  19          NSLog(@"delete obj failure");
  20      }
  21    });
  22    [task waitUtilFinished];
  23}

Copy Object

Simply Copy Object

• Basic workflow

  1. Instantiate the BOSClient class.
  2. Execute the BOSClient.copyObject method.
  3. Return a BOSCopyObjectResponse instance. The eTag and last modification timestamp can be accessed via eTag/lastModified, among other methods.

• Example code

  Swift Copy

  1BOSCopyObjectRequest* request = [[BOSCopyObjectRequest alloc] init];
  2request.bucket = @"<bucketname>";
  3request.key = @"<objectname>";
  4request.source = @"<sourceBucket>/<sourceObject";
  5__block BOSCopyObjectResponse* response = nil;
  6BCETask* task = [client copyObject:request];
  7task.then(^(BCEOutput* output) {
  8    if (output.response) {
  9        response = (BOSCopyObjectResponse*)output.response;
  10        NSLog(@"copy obj success!");
  11    }
  12    if (output.error) {
  13        NSLog(@"copy obj failure");
  14    }
  15});
  16[task waitUtilFinished];

• Complete example

  Swift Copy

  1#import <BaiduBCEBasic/BaiduBCEBasic.h>
  2#import <BaiduBCEBOS/BaiduBCEBOS.h>
  3void example(void) {
  4 // Initialize
  5    BCECredentials* credentials = [[BCECredentials alloc] init];
  6    credentials.accessKey = @"<access key>";
  7    credentials.secretKey = @"<secret key>";
  8    BOSClientConfiguration* configuration = [[BOSClientConfiguration alloc] init];
  9    configuration.credentials = credentials;
  10    BOSClient* client = [[BOSClient alloc] initWithConfiguration:configuration];
  11    BOSCopyObjectRequest* request = [[BOSCopyObjectRequest alloc] init];
  12    request.bucket = @"<bucketname>";
  13    request.key = @"<objectname>";
  14    request.source = @"<sourceBucket>/<sourceObject";
  15    __block BOSCopyObjectResponse* response = nil;
  16    BCETask* task = [client copyObject:request];
  17    task.then(^(BCEOutput* output) {
  18      if (output.response) {
  19          response = (BOSCopyObjectResponse*)output.response;
  20          NSLog(@"copy obj success!");
  21      }
  22      if (output.error) {
  23          NSLog(@"copy obj failure");
  24      }
  25    });
  26    [task waitUtilFinished];
  27}

  Plain Text Copy

  1> **Note:** The copyObject method returns a  `BOSCopyObjectResponse` object containing the new object's ETag and modification time.

Copy object with specified conditions

Copy an object with conditions specified. This functionality is typically applied in scenarios like:

• Copy an object while resetting its metadata.
• Resetting the metadata of an existing object by setting both the source and the target to the same object.
• Copy when the eTag of the source object is the same as the specified eTag;
• Copy when the eTag of the source object is the different from the specified eTag;
• Copy when the source object has not been modified after the specified time;
• Copy when the source object has been modified after the specified time;

Details as follows:

• Basic workflow

  1. Create an instance of the BOSCopyObjectRequest class, and pass in the parameters <source>, <ifMatchEtag>, <ifNotMatchEtag>, <ifModifiedSince>, <ifUnmodifiedSince>, <metadataDirective>.
  2. Return a BOSCopyObjectResponse instance. The eTag and last modification timestamp can be accessed via eTag/lastModified, among other methods.

• Example code

  Swift Copy

  1BOSCopyObjectRequest* request = [[BOSCopyObjectRequest alloc] init];
  2request.bucket = @"<bucketname>";
  3request.key = @"<objectname>";
  4request.source = @"<sourceBucket>/<sourceObject";
  5request.metadataDirective = @"replace";
  6request.ifModifiedSince = @"Wed, 01 Mar 2006 12:00:00 GMT";
  7__block BOSCopyObjectResponse* response = nil;
  8BCETask* task = [client copyObject:request];
  9task.then(^(BCEOutput* output) {
  10  if (output.response) {
  11      response = (BOSCopyObjectResponse*)output.response;
  12      NSLog(@"copy obj success!");
  13  }
  14  if (output.error) {
  15      NSLog(@"copy obj failure");
  16  }
  17});
  18[task waitUtilFinished];

  Plain Text Copy

  1> **Note:**`BOSCopyObjectRequest` allows users to modify the ObjectMeta of the target object and also provides the setting of the `MatchingETagConstraints` parameter.

Multipart upload of objects

In addition to using the putObject() method for file uploads to BOS, BOS also supports another upload mode called Multipart Upload. This mode can be used in scenarios such as:

• When resumable uploads are required.
• When uploading files larger than 5GB.
• When the connection to the BOS server is frequently interrupted due to unstable network conditions.
• Enable streaming file uploads.
• The file size cannot be determined before uploading.

Complete Multipart Upload in parts

Suppose there is a file with the local path /path/to/file.zip. Since the file is large, multipart upload is used to transmit it to BOS.

• Basic workflow

  1. Start a multipart upload.
  2. Upload individual parts.
  3. Finalize the multipart upload.

Initialize multipart upload

Use initiateMultipartUpload method to initialize a multipart upload event:

• Example code

  Swift Copy

  1BOSInitiateMultipartUploadRequest* initMPRequest = [[BOSInitiateMultipartUploadRequest alloc] init];
  2initMPRequest.bucket = @"<bucketname>";
  3initMPRequest.key = @"<objectname>";
  4initMPRequest.contentType = @"<content type>";
  5__block BOSInitiateMultipartUploadResponse* initMPResponse = nil;
  6BCETask* task = [client initiateMultipartUpload:initMPRequest];
  7task.then(^(BCEOutput* output) {
  8  if (output.response) {
  9      initMPResponse = (BOSInitiateMultipartUploadResponse*)output.response;
  10      NSLog(@"initiate multipart upload success!");
  11  }
  12  if (output.error) {
  13      NSLog(@"initiate multipart upload failure");
  14  }
  15});
  16[task waitUtilFinished];
  17NSString* uploadID = initMPResponse.uploadId;

  Plain Text Copy

  1> **Note:**`The return result of initiateMultipartUpload` contains `UploadId`, which is the unique identifier for distinguishing multipart upload events, and we will use it in subsequent operations.

Upload parts

Upload the file in segments.

• Example code

  Swift Copy

  1// Calculate the count of parts
  2NSString* file = @"/path/to/file.zip";
  3NSDictionary<NSString*, id>* attr = [[NSFileManager defaultManager] attributesOfItemAtPath:file error:nil];
  4uint64_t fileSize = attr.fileSize;
  5uint64_t partSize = 1024 * 1024 * 5L;
  6uint64_t partCount = fileSize / partSize;
  7if (fileSize % partSize != 0) {
  8  ++partCount;
  9}
  10NSMutableArray<BOSPart*>* parts = [NSMutableArray array];
  11NSFileHandle* handle = [NSFileHandle fileHandleForReadingAtPath:@"/path/to/file.zip"];
  12for (uint64_t i = 0; i < partCount; ++i) {
  13  // seek
  14  uint64_t skip = partSize * i;
  15  [handle seekToFileOffset:skip];
  16  uint64_t size = (partSize < fileSize - skip) ? partSize : fileSize - skip;
  17  // data
  18  NSData* data = [handle readDataOfLength:size];
  19  // request
  20  BOSUploadPartRequest* uploadPartRequest = [[BOSUploadPartRequest alloc] init];
  21  uploadPartRequest.bucket = @"<bucketname>";
  22  uploadPartRequest.key = @"<objectname>";
  23  uploadPartRequest.objectData.data = data;
  24  uploadPartRequest.partNumber = i + 1;
  25  uploadPartRequest.uploadId = uploadID;
  26  __block BOSUploadPartResponse* uploadPartResponse = nil;
  27  task = [client uploadPart:uploadPartRequest];
  28  task.then(^(BCEOutput* output) {
  29      if (output.response) {
  30          uploadPartResponse = (BOSUploadPartResponse*)output.response;
  31          BOSPart* part = [[BOSPart alloc] init];
  32          part.partNumber = i + 1;
  33          part.eTag = uploadPartResponse.eTag;
  34                  [parts addObject:part];
  35      }
  36  });
  37  [task waitUtilFinished];
  38}

  Plain Text Copy

  1> **Note:** The core of the above code is to call the `UploadPart` method to upload each part concurrently, but the following points should be noted:
  2>
  3> -   The `uploadPart` method mandates that the size of each part, except for the last one, must be at least 5 MB. However, this size requirement is only validated when the multipart upload is finalized, not during the `Upload Part` operation itself.
  4> -   To ensure no errors during network transmission, it is recommended to use the Content-MD5 value returned by BOS for each part after `uploadPart` to verify the correctness of the uploaded part data. When all part data is combined into one Object, it no longer contains the MD5 value.
  5> -   The part number must be within the range of 1 to 10,000. If this limit is exceeded, BOS will return an InvalidArgument error code.  
  6> -   For each uploaded part, the stream must be positioned at the beginning of the respective part.  
  7> -   After each Part upload, the return result of BOS will include a `BOSPart` object, which is a combination of the uploaded block's ETag and block number (PartNumber). It will be used in subsequent steps to complete the multipart upload, so it must be saved. Generally speaking, these `BOSPart` objects will be saved in an array.

Complete multipart upload

• Example code

  Swift Copy

  1BOSCompleteMultipartUploadRequest* compMultipartRequest = [[BOSCompleteMultipartUploadRequest alloc] init];
  2compMultipartRequest.bucket = @"<bucketname>";
  3compMultipartRequest.key = @"<objectname>";
  4compMultipartRequest.uploadId = uploadID;
  5compMultipartRequest.parts = parts;
  6__block BOSCompleteMultipartUploadResponse* complResponse = nil;
  7task = [client completeMultipartUpload:compMultipartRequest];
  8task.then(^(BCEOutput* output) {
  9  if (output.response) {
  10      complResponse = (BOSCompleteMultipartUploadResponse*)output.response;
  11      NSLog(@"complte multiparts success!");
  12  }
  13  if (output.error) {
  14      NSLog(@"complte multiparts failure %@", output.error);
  15  }
  16});
  17[task waitUtilFinished];

  Plain Text Copy

  1> **Note:** The `parts` in the above code is the list of parts saved in the second step. After BOS receives the list of parts submitted by the user, it will verify the validity of each data Part one by one. Once all data parts are validated, BOS will assemble the data parts into a complete Object.

• Complete example

  Swift Copy

  1#import <BaiduBCEBasic/BaiduBCEBasic.h>
  2#import <BaiduBCEBOS/BaiduBCEBOS.h>
  3void example(void) {
  4// Initialize
  5BCECredentials* credentials = [[BCECredentials alloc] init];
  6credentials.accessKey = @"<access key>";
  7credentials.secretKey = @"<secret key>";
  8BOSClientConfiguration* configuration = [[BOSClientConfiguration alloc] init];
  9configuration.credentials = credentials;
  10BOSClient* client = [[BOSClient alloc] initWithConfiguration:configuration];
  11// Initialize multipart upload
  12BOSInitiateMultipartUploadRequest* initMPRequest = [[BOSInitiateMultipartUploadRequest alloc] init];
  13initMPRequest.bucket = @"<bucketname>";
  14initMPRequest.key = @"<objectname>";
  15initMPRequest.contentType = @"<content type>";
  16 __block BOSInitiateMultipartUploadResponse* initMPResponse = nil;
  17 BCETask* task = [client initiateMultipartUpload:initMPRequest];
  18 task.then(^(BCEOutput* output) {
  19     if (output.response) {
  20         initMPResponse = (BOSInitiateMultipartUploadResponse*)output.response;
  21         NSLog(@"initiate multipart upload success!");
  22     }
  23     if (output.error) {
  24         NSLog(@"initiate multipart upload failure");
  25     }
  26 });
  27 [task waitUtilFinished];
  28 NSString* uploadID = initMPResponse.uploadId;
  29// Calculate the count of parts
  30 NSString* file = @"/path/to/file.zip";
  31 NSDictionary<NSString*, id>* attr = [[NSFileManager defaultManager] attributesOfItemAtPath:file error:nil];
  32 uint64_t fileSize = attr.fileSize;
  33 uint64_t partSize = 1024 * 1024 * 5L;
  34 uint64_t partCount = fileSize / partSize;
  35 if (fileSize % partSize != 0) {
  36     ++partCount;
  37 }
  38 NSMutableArray<BOSPart*>* parts = [NSMutableArray array];
  39 NSFileHandle* handle = [NSFileHandle fileHandleForReadingAtPath:@"/path/to/file.zip"];
  40 for (uint64_t i = 0; i < partCount; ++i) {
  41     // seek
  42     uint64_t skip = partSize * i;
  43     [handle seekToFileOffset:skip];
  44     uint64_t size = (partSize < fileSize - skip) ? partSize : fileSize - skip;
  45     // data
  46     NSData* data = [handle readDataOfLength:size];
  47     // request
  48     BOSUploadPartRequest* uploadPartRequest = [[BOSUploadPartRequest alloc] init];
  49     uploadPartRequest.bucket = @"<bucketname>";
  50     uploadPartRequest.key = @"<objectname>";
  51     uploadPartRequest.objectData.data = data;
  52     uploadPartRequest.partNumber = i + 1;
  53     uploadPartRequest.uploadId = uploadID;
  54     __block BOSUploadPartResponse* uploadPartResponse = nil;
  55     task = [client uploadPart:uploadPartRequest];
  56     task.then(^(BCEOutput* output) {
  57         if (output.response) {
  58             uploadPartResponse = (BOSUploadPartResponse*)output.response;
  59             BOSPart* part = [[BOSPart alloc] init];
  60             part.partNumber = i + 1;
  61             part.eTag = uploadPartResponse.eTag;
  62                     [parts addObject:part];
  63         }
  64     });
  65     [task waitUtilFinished];
  66 }
  67 BOSCompleteMultipartUploadRequest* compMultipartRequest = [[BOSCompleteMultipartUploadRequest alloc] init];
  68 compMultipartRequest.bucket = @"<bucketname>";
  69 compMultipartRequest.key = @"<objectname>";
  70 compMultipartRequest.uploadId = uploadID;
  71 compMultipartRequest.parts = parts;
  72 __block BOSCompleteMultipartUploadResponse* complResponse = nil;
  73 task = [client completeMultipartUpload:compMultipartRequest];
  74 task.then(^(BCEOutput* output) {
  75     if (output.response) {
  76         complResponse = (BOSCompleteMultipartUploadResponse*)output.response;
  77         NSLog(@"complte multiparts success!");
  78     }
  79     if (output.error) {
  80         NSLog(@"complte multiparts failure %@", output.error);
  81     }
  82 });
  83 [task waitUtilFinished];
  84}

Cancel multipart upload

Users can cancel multipart uploads by using the abortMultipartUpload method.

• Example code

  Swift Copy

  1BOSAbortMultipartUploadRequest* abortRequest = [[BOSAbortMultipartUploadRequest alloc] init];
  2abortRequest.bucket = @"bucket";
  3abortRequest.key = @"<objectname>";
  4abortRequest.uploadId = uploadID;
  5__block BOSAbortMultipartUploadResponse* abortResponse = nil;
  6task = [client abortMultipartUpload:abortRequest];
  7task.then(^(BCEOutput* output) {
  8  if (output.response) {
  9      abortResponse = (BOSAbortMultipartUploadResponse*)output.response;
  10      NSLog(@"abort multiparts success!");
  11  }
  12  if (output.error) {
  13      NSLog(@"abort multiparts failure %@", output.error);
  14  }
  15});
  16[task waitUtilFinished];

Retrieve unfinished multipart uploads

Users can obtain the unfinished multipart upload events in the bucket by the listMultipartUploads method.

• Basic workflow

  1. Create an instance of the BOSListMultipartUploadsRequest class, and pass in the parameter <BucketName>.
  2. Instantiate the BOSClient class and call its listMultipartUploads method.
  3. The listMultipartUploads method provides details about all ongoing multipart uploads.

• Example code

  Swift Copy

  1BOSListMultipartUploadsRequest* listMultipartRequest = [[BOSListMultipartUploadsRequest alloc] init];
  2listMultipartRequest.bucket = @"<bucketname>";
  3__block BOSListMultipartUploadsResponse* listMultipartResponse = nil;
  4task = [client listMultipartUploads:listMultipartRequest];
  5task.then(^(BCEOutput* output) {
  6  if (output.response) {
  7      listMultipartResponse = (BOSListMultipartUploadsResponse*)output.response;
  8      NSLog(@"list multipart success");
  9  }
  10  if (output.error) {
  11      NSLog(@"list multipart failure %@", output.error);
  12  }
  13});
  14[task waitUtilFinished];

  Plain Text Copy

  1> **Note:**
  2>
  3> -   By default, if there are more than 1,000 multipart upload events in a bucket, only 1,000 entries will be returned. The IsTruncated field in the response will be True, and the nextKeyMarker will indicate the starting point for subsequent data.  
  4> -   To fetch additional multipart upload events, use the keyMarker parameter to read data in batches.  

• Complete example

  Swift Copy

  1#import <BaiduBCEBasic/BaiduBCEBasic.h>
  2#import <BaiduBCEBOS/BaiduBCEBOS.h>
  3void example(void) {
  4 // Initialize
  5    BCECredentials* credentials = [[BCECredentials alloc] init];
  6    credentials.accessKey = @"<access key>";
  7    credentials.secretKey = @"<secret key>";
  8    BOSClientConfiguration* configuration = [[BOSClientConfiguration alloc] init];
  9    configuration.credentials = credentials;
  10    BOSClient* client = [[BOSClient alloc] initWithConfiguration:configuration];
  11    BOSListMultipartUploadsRequest* listMultipartRequest = [[BOSListMultipartUploadsRequest alloc] init];
  12    listMultipartRequest.bucket = @"<bucketname>";
  13    __block BOSListMultipartUploadsResponse* listMultipartResponse = nil;
  14    BCETask* task = [client listMultipartUploads:listMultipartRequest];
  15    task.then(^(BCEOutput* output) {
  16      if (output.response) {
  17          listMultipartResponse = (BOSListMultipartUploadsResponse*)output.response;
  18          NSLog(@"list multipart success");
  19      }
  20      if (output.error) {
  21          NSLog(@"list multipart failure %@", output.error);
  22      }
  23    });
  24    [task waitUtilFinished];
  25    for (BOSMultipartUpload* upload in listMultipartResponse.uploads) {
  26        NSLog(@"upload id : %@", upload.uploadId);
  27    }
  28}

Get all uploaded part information

Users can obtain all uploaded parts in an upload event by the listParts method.

• Basic workflow

  1. Create an instance of the BOSListPartsRequest class, and pass in the parameters <BucketName>, <ObjectKey> and <UploadId>
  2. Instantiate the BOSClient class and call its listParts method.
  3. The listParts method provides information about all the parts that have been uploaded.

• Example code

  Swift Copy

  1BOSListPartsRequest* listPartsRequest = [[BOSListPartsRequest alloc] init];
  2listPartsRequest.bucket = @"<bucketname>";
  3listPartsRequest.key = @"<objectname>";
  4listPartsRequest.uploadId = @"<upload id>";;
  5__block BOSListPartsResponse* listPartsResponse = nil;
  6BCETask* task = [client listParts:listPartsRequest];
  7task.then(^(BCEOutput* output) {
  8  if (output.response) {
  9      listPartsResponse = (BOSListPartsResponse*)output.response;
  10      NSLog(@"list parts success!");
  11  }
  12  if (output.error) {
  13      NSLog(@"list part failure %@", output.error);
  14  }
  15});
  16[task waitUtilFinished];
  17for (BOSPart* part in listPartsResponse.parts) {
  18    NSLog(@"part etag %@", part.eTag);
  19}

  Plain Text Copy

  1> **Note:**
  2>
  3> -   By default, if the number of multipart upload events in a bucket surpasses 1,000, only 1,000 records will be returned. In such cases, the IsTruncated value in the response will be True, and the NextPartNumberMarker will indicate the starting point for the next query.  
  4> -   To retrieve more information about uploaded parts, use the PartNumberMarker parameter to fetch data in batches.  

• Complete example

  Swift Copy

  1#import <BaiduBCEBasic/BaiduBCEBasic.h>
  2#import <BaiduBCEBOS/BaiduBCEBOS.h>
  3void example(void) {
  4 // Initialize
  5    BCECredentials* credentials = [[BCECredentials alloc] init];
  6    credentials.accessKey = @"<access key>";
  7    credentials.secretKey = @"<secret key>";
  8    BOSClientConfiguration* configuration = [[BOSClientConfiguration alloc] init];
  9    configuration.credentials = credentials;
  10    BOSClient* client = [[BOSClient alloc] initWithConfiguration:configuration];
  11    BOSListPartsRequest* listPartsRequest = [[BOSListPartsRequest alloc] init];
  12    listPartsRequest.bucket = @"<bucketname>";
  13    listPartsRequest.key = @"<objectname>";
  14    listPartsRequest.uploadId = @"<upload id>";;
  15    __block BOSListPartsResponse* listPartsResponse = nil;
  16    BCETask* task = [client listParts:listPartsRequest];
  17    task.then(^(BCEOutput* output) {
  18    if (output.response) {
  19        listPartsResponse = (BOSListPartsResponse*)output.response;
  20        NSLog(@"list parts success!");
  21    }
  22    if (output.error) {
  23        NSLog(@"list part failure %@", output.error);
  24    }
  25    });
  26    [task waitUtilFinished];
  27    for (BOSPart* part in listPartsResponse.parts) {
  28        NSLog(@"part etag %@", part.eTag);
  29    }
  30}