Get Object

Updated at：2025-11-03

Simple object get

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

Basic workflow

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

Example code

Swift

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;

Note:

BOSObjectContent contains detailed information about the object, including its bucket location, object name, metadata, and data storage.

BOSObjectMetadata includes the ETag set during the object upload, HTTP headers, and custom metadata.

Retrieve the object's data through the objectData property of BOSObjectContent.

Complete example

Swift

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

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

Example code

Swift

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;

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

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

Example code

Swift

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:

Swift

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

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

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

Example code

Swift

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

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}

Multipart upload of objects

View the object in the bucket