Overview

This document provides an overview of APIs and SDK code samples related to querying object metadata.

SDK API References

For parameters and method description of all APIs in the SDK, please see SDK API Reference.

Querying Object Metadata

Description

This API is used to query the metadata of an object.

Sample code

Objective-C

QCloudHeadObjectRequest* headerRequest = [QCloudHeadObjectRequest new];
// Object key, i.e. the full path of a COS object. If the object is in a directory, the path should be "video/xxx/movie.mp4"
headerRequest.object = @"exampleobject";
// versionId specifies the version ID of an object to query (if versioning is enabled). If versionId is not specified, the latest version will be queried.
headerRequest.versionID = @"versionID";
// Bucket name in the format of BucketName-Appid, which can be viewed in the COS console at https://console.cloud.tencent.com/cos5/bucket
headerRequest.bucket = @"examplebucket-1250000000";
[headerRequest setFinishBlock:^(NSDictionary* result, NSError *error) {
   // "result" contains the request result.
   // Obtain the CRC64 value of the object.
    NSString * crc64 = [[outputObject __originHTTPURLResponse__].allHeaderFields valueForKey:@"x-cos-hash-crc64ecma"];
}];
[[QCloudCOSXMLService defaultCOSXML] HeadObject:headerRequest];

Note：

For the complete sample, go to GitHub.

Swift

let headObject = QCloudHeadObjectRequest.init();
// Bucket name in the format of BucketName-Appid, which can be viewed in the COS console at https://console.cloud.tencent.com/cos5/bucket
headObject.bucket = "examplebucket-1250000000";
// versionId specifies the version ID of an object to query (if versioning is enabled). If versionId is not specified, the latest version will be queried.
headObject.versionID = "versionID";
// Object key, i.e. the full path of a COS object. If the object is in a directory, the path should be "video/xxx/movie.mp4"
headObject.object  = "exampleobject";
headObject.finishBlock =  {(result,error) in
  if let result = result {
      // Obtain the CRC64 value of the object.
      let crc64 = result?.__originHTTPURLResponse__.allHeaderFields["x-cos-hash-crc64ecma"];

  } else {
      print(error!);
  }
}
QCloudCOSXMLService.defaultCOSXML().headObject(headObject);

Note：

For the complete sample, go to GitHub.