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 from other Alibaba Cloud services in the same region as OSS, use an internal endpoint. For more information about OSS regions and endpoints, 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:GetBucketLocationpermission. 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 any OSS region. Example: https://oss-cn-hangzhou.aliyuncs.com. */
const char *endpoint = "yourEndpoint";
/* Specify the bucket name. */
const char *bucket_name = "yourBucket";
/* Set yourRegion to the region where the bucket is located. For example, if the bucket is in the China (Hangzhou) region, set the region to cn-hangzhou. */
const char *region = "yourRegion";
void init_options(oss_request_options_t *options)
{
options->config = oss_config_create(options->pool);
/* Initialize an aos_string_t type with a char* string. */
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 set. */
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"));
// Configure the following two parameters.
aos_str_set(&options->config->region, region);
options->config->signature_version = 4;
/* Specify whether to use a CNAME to access OSS. A value of 0 indicates that a CNAME is not used. */
options->config->is_cname = 0;
/* Set 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 at the program entry to initialize global resources such as the network and memory. */
if (aos_http_io_initialize(NULL, 0) != AOSE_OK) {
exit(1);
}
/* The memory pool (pool) is used for memory management and is equivalent to apr_pool_t. The implementation code is in the apr library. */
aos_pool_t *pool;
/* Create a memory pool. The second parameter is NULL, which indicates that the memory pool does not inherit from another memory pool. */
aos_pool_create(&pool, NULL);
/* Create and initialize options. The options include global configurations such as endpoint, access_key_id, access_key_secret, is_cname, and curl. */
oss_request_options_t *oss_client_options;
/* Allocate memory to options in the memory pool. */
oss_client_options = oss_request_options_create(pool);
/* Initialize the client options oss_client_options. */
init_options(oss_client_options);
/* Initialize parameters. */
aos_string_t bucket;
aos_string_t oss_location;
aos_table_t *resp_headers = NULL;
aos_status_t *resp_status = NULL;
/* Assign the char* data to the aos_string_t bucket. */
aos_str_set(&bucket, bucket_name);
/* Get 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", oss_location.data);
} else {
printf("get bucket location failed\n");
}
/* Release the memory pool. This releases the memory allocated for various resources during the request. */
aos_pool_destroy(pool);
/* Release the previously allocated global resources. */
aos_http_io_deinitialize();
return 0;
}References
For information about the API operation that you can call to retrieve the region of a bucket, see GetBucketLocation.