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Object Storage Service:Query the region of a bucket

Last Updated:Jan 15, 2024

A bucket is a container that is used to store objects in Object Storage Service (OSS). Every object is contained in a bucket. This topic describes how to query the region of a bucket.

Usage notes

  • In this topic, the public endpoint of the China (Hangzhou) region is used. If you want to access OSS by using other Alibaba Cloud services in the same region as OSS, use an internal endpoint. For more information about the regions and endpoints supported by OSS, see Regions and endpoints.

  • In this topic, an OSSClient instance is created by using an OSS endpoint. If you want to create an OSSClient instance by using custom domain names or Security Token Service (STS), see Initialization.

  • To query the region of a bucket, you must have the oss:GetBucketLocation permission. For more information, see Attach a custom policy to a RAM user.

Sample code

The following sample code shows how to query the region or location of a bucket:

#include "oss_api.h"
#include "aos_http_io.h"
/* Specify the endpoint of a region that is supported by OSS. Example: */
const char *endpoint = "yourEndpoint";

/* Specify the bucket name. */
const char *bucket_name = "yourBucket";
void init_options(oss_request_options_t *options)
    options->config = oss_config_create(options->pool);
    /* Use a char* string to initialize data of the aos_string_t type. */
    aos_str_set(&options->config->endpoint, endpoint);
    /* Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured. */    
    aos_str_set(&options->config->access_key_id, getenv("OSS_ACCESS_KEY_ID"));
    aos_str_set(&options->config->access_key_secret, getenv("OSS_ACCESS_KEY_SECRET"));
    /* Specify whether to use CNAME to access OSS. The value 0 indicates that CNAME is not used. */
    options->config->is_cname = 0;
    /* Configure network parameters, such as the timeout period. */
    options->ctl = aos_http_controller_create(options->pool, 0);
int main(int argc, char *argv[])
    /* Call the aos_http_io_initialize method in main() to initialize global resources, such as network and memory resources. */
    if (aos_http_io_initialize(NULL, 0) != AOSE_OK) {
    /* Create a pool for memory management. aos_pool_t is equivalent to apr_pool_t. The code that is used to create a memory pool is included in the APR library. */
    aos_pool_t *pool;
    /* Create a memory pool. The value of the second parameter is NULL. This value indicates that the pool does not inherit other memory pools. */
    aos_pool_create(&pool, NULL);
    /* Create and initialize options. This parameter includes global configuration information, such as endpoint, access_key_id, access_key_secret, is_cname, and curl. */
    oss_request_options_t *oss_client_options;
    /* Allocate the memory resources in the memory pool to the options. */
    oss_client_options = oss_request_options_create(pool);
    /* Initialize oss_client_options. */
    /* Initialize the parameters. */
    aos_string_t bucket;
    aos_string_t oss_location;
    aos_table_t *resp_headers = NULL; 
    aos_status_t *resp_status = NULL; 
    /* Assign char* data to a bucket of the aos_string_t type. */
    aos_str_set(&bucket, bucket_name);
    /* Query the region of the bucket. */
    resp_status = oss_get_bucket_location(oss_client_options, &bucket, &oss_location, &resp_headers);
    if (aos_status_is_ok(resp_status)) {
        printf("get bucket location succeeded : %s \n",;
    } else {
        printf("get bucket location failed\n");
    /* Release the memory pool. This operation releases memory resources allocated for the request. */
    /* Release the allocated global resources. */
    return 0;


For more information about the API operation that you can call to query the region of a bucket, see GetBucketLocation.