reduce storage costs with lifecycle rules using the c sdk - Object Storage Service

Not all data uploaded to Object Storage Service (OSS) is accessed frequently. However, some data must be stored in a cold storage class for reasons such as data compliance or archiving. In other scenarios, you may want to batch delete data that is no longer needed in a bucket. You can configure lifecycle rules based on the last modified time to periodically transition objects from hot to cold storage classes or delete objects. This helps reduce storage costs.

Notes

Before you configure lifecycle rules based on the last modified time of objects, make sure that you familiarize yourself with this feature. For more information, see Lifecycle rules based on the last modified time.

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 configure lifecycle rules, you must have the oss:PutBucketLifecycle permission. To query lifecycle rules, you must have the oss:GetBucketLifecycle permission. To clear lifecycle rules, you must have the oss:DeleteBucketLifecycle permission. For more information, see Attach a custom policy to a RAM user.

Set lifecycle rules

The following code shows how to set lifecycle rules for a bucket named examplebucket based on the last modified time. After you set the rules, if you want to modify one or more of them, see How do I modify one or more lifecycle rule configurations?.

#include "oss_api.h"
#include "aos_http_io.h"
/* Replace yourEndpoint with the Endpoint of the region where your bucket is located. For example, for the China (Hangzhou) region, the Endpoint is https://oss-cn-hangzhou.aliyuncs.com. */
const char *endpoint = "yourEndpoint";
/* Replace with your bucket name. For example, examplebucket. */
const char *bucket_name = "examplebucket";
/* Replace yourRegion with the ID of the region where your bucket is located. For example, for the China (Hangzhou) region, the region ID is 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 variable with a char* string. */
    aos_str_set(&options->config->endpoint, endpoint);
    /* Obtain access credentials from environment variables. Before you run this sample code, make sure 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"));
    // You must also 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 means 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 point 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) for memory management is equivalent to apr_pool_t. The implementation is in the apr library. */
    aos_pool_t *pool;
    /* Create a memory pool. The second parameter is NULL, which indicates that the new memory pool does not inherit from another memory pool. */
    aos_pool_create(&pool, NULL);
    /* Create and initialize options. This parameter includes global configurations, such as endpoint, access_key_id, access_key_secret, is_cname, and curl. */
    oss_request_options_t *oss_client_options;
    /* Allocate memory for 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_table_t *resp_headers = NULL; 
    aos_status_t *resp_status = NULL; 
    aos_str_set(&bucket, bucket_name);
    aos_list_t lifecycle_rule_list;   
    aos_str_set(&bucket, bucket_name);
    aos_list_init(&lifecycle_rule_list);
    /* Specify the expiration in days. */
    oss_lifecycle_rule_content_t *rule_content_days = oss_create_lifecycle_rule_content(pool);
    aos_str_set(&rule_content_days->id, "rule-1");
    /* Set the object prefix. */
    aos_str_set(&rule_content_days->prefix, "dir1");
    aos_str_set(&rule_content_days->status, "Enabled");
    rule_content_days->days = 3;
    aos_list_add_tail(&rule_content_days->node, &lifecycle_rule_list);
    /* Specify the expiration date. */
    oss_lifecycle_rule_content_t *rule_content_date = oss_create_lifecycle_rule_content(pool);
    aos_str_set(&rule_content_date->id, "rule-2");
    aos_str_set(&rule_content_date->prefix, "dir2");
    aos_str_set(&rule_content_date->status, "Enabled");
    /* The expiration date must be in UTC format.
    aos_str_set(&rule_content_date->date, "2023-10-11T00:00:00.000Z");
    aos_list_add_tail(&rule_content_date->node, &lifecycle_rule_list);
    /* Set the lifecycle rule. */
    resp_status = oss_put_bucket_lifecycle(oss_client_options, &bucket, &lifecycle_rule_list, &resp_headers);
    if (aos_status_is_ok(resp_status)) {
        printf("put bucket lifecycle succeeded\n");
    } else {
        printf("put bucket lifecycle failed, code:%d, error_code:%s, error_msg:%s, request_id:%s\n",
            resp_status->code, resp_status->error_code, resp_status->error_msg, resp_status->req_id);
    }
    /* Release the memory pool. This releases the memory allocated to resources during the request. */
    aos_pool_destroy(pool);
    /* Release the previously allocated global resources. */
    aos_http_io_deinitialize();
    return 0;
}

View lifecycle rules

The following code provides an example on how to query the lifecycle rules configured for the bucket named examplebucket:

#include "oss_api.h"
#include "aos_http_io.h"
/* Replace yourEndpoint with the Endpoint of the region where your bucket is located. For example, for the China (Hangzhou) region, the Endpoint is https://oss-cn-hangzhou.aliyuncs.com. */
const char *endpoint = "yourEndpoint";
/* Replace with your bucket name. For example, examplebucket. */
const char *bucket_name = "examplebucket";
/* Replace yourRegion with the ID of the region where your bucket is located. For example, for the China (Hangzhou) region, the region ID is 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 variable with a char* string. */
    aos_str_set(&options->config->endpoint, endpoint);
    /* Obtain access credentials from environment variables. Before you run this sample code, make sure 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"));
    // You must also 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 means 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 point 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) for memory management is equivalent to apr_pool_t. The implementation is in the apr library. */
    aos_pool_t *pool;
    /* Create a memory pool. The second parameter is NULL, which indicates that the new memory pool does not inherit from another memory pool. */
    aos_pool_create(&pool, NULL);
    /* Create and initialize options. This parameter includes global configurations, such as endpoint, access_key_id, access_key_secret, is_cname, and curl. */
    oss_request_options_t *oss_client_options;
    /* Allocate memory for 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_table_t *resp_headers = NULL; 
    aos_status_t *resp_status = NULL; 
    aos_list_t lifecycle_rule_list;
    oss_lifecycle_rule_content_t *rule_content;
    char *rule_id = NULL; 
    char *prefix = NULL; 
    char *status = NULL; 
    int days = INT_MAX;
    char* date = "";
    aos_str_set(&bucket, bucket_name);
    /* Get the lifecycle rules of the bucket. */
    aos_list_init(&lifecycle_rule_list);
    resp_status = oss_get_bucket_lifecycle(oss_client_options, &bucket, &lifecycle_rule_list, &resp_headers);
    if (aos_status_is_ok(resp_status)) {
        printf("get bucket lifecycle succeeded\n");
        aos_list_for_each_entry(oss_lifecycle_rule_content_t, rule_content, &lifecycle_rule_list, node) {
            rule_id = apr_psprintf(pool, "%.*s", rule_content->id.len, rule_content->id.data);
            prefix = apr_psprintf(pool, "%.*s", rule_content->prefix.len, rule_content->prefix.data);
            status = apr_psprintf(pool,"%.*s", rule_content->status.len, rule_content->status.data);
            date = apr_psprintf(pool, "%.*s", rule_content->date.len, rule_content->date.data);
            days = rule_content->days;
            printf("rule_id: %s \n", rule_id);
            printf("prefix: %s \n", prefix);
            printf("status: %s \n", status);
            printf("date: %s \n", date);
            printf("days: %d \n", days);
        }
    } else {
        printf("get bucket lifecycle failed, code:%d, error_code:%s, error_msg:%s, request_id:%s\n",
            resp_status->code, resp_status->error_code, resp_status->error_msg, resp_status->req_id);
    }
    /* Release the memory pool. This releases the memory allocated to resources during the request. */
    aos_pool_destroy(pool);
    /* Release the previously allocated global resources. */
    aos_http_io_deinitialize();
    return 0;
}

Delete all lifecycle rules

The following code provides an example on how to clear lifecycle rules in a bucket named examplebucket. If you want to delete one or more lifecycle rules, refer to How do I delete one or more lifecycle rules?.

#include "oss_api.h"
#include "aos_http_io.h"
/* Replace yourEndpoint with the Endpoint of the region where your bucket is located. For example, for the China (Hangzhou) region, the Endpoint is https://oss-cn-hangzhou.aliyuncs.com. */
const char *endpoint = "yourEndpoint";
/* Replace with your bucket name. For example, examplebucket. */
const char *bucket_name = "examplebucket";
/* Replace yourRegion with the ID of the region where your bucket is located. For example, for the China (Hangzhou) region, the region ID is 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 variable with a char* string. */
    aos_str_set(&options->config->endpoint, endpoint);
    /* Obtain access credentials from environment variables. Before you run this sample code, make sure 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"));
    // You must also 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 means 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 point 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) for memory management is equivalent to apr_pool_t. The implementation is in the apr library. */
    aos_pool_t *pool;
    /* Create a memory pool. The second parameter is NULL, which indicates that the new memory pool does not inherit from another memory pool. */
    aos_pool_create(&pool, NULL);
    /* Create and initialize options. This parameter includes global configurations, such as endpoint, access_key_id, access_key_secret, is_cname, and curl. */
    oss_request_options_t *oss_client_options;
    /* Allocate memory for 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_table_t *resp_headers = NULL; 
    aos_status_t *resp_status = NULL; 
    aos_str_set(&bucket, bucket_name);
    /* Delete the lifecycle rules of the bucket. */
    aos_str_set(&bucket, bucket_name);
    resp_status = oss_delete_bucket_lifecycle(oss_client_options, &bucket, &resp_headers);
    if (aos_status_is_ok(resp_status)) {
        printf("delete bucket lifecycle succeeded\n");
    } else {
        printf("delete bucket lifecycle failed, code:%d, error_code:%s, error_msg:%s, request_id:%s\n",
            resp_status->code, resp_status->error_code, resp_status->error_msg, resp_status->req_id);
    }
    /* Release the memory pool. This releases the memory allocated to resources during the request. */
    aos_pool_destroy(pool);
    /* Release the previously allocated global resources. */
    aos_http_io_deinitialize();
    return 0;
}

References

For more information about the API operation to set lifecycle rules, see PutBucketLifecycle.
For more information about the API operation to view lifecycle rules, see GetBucketLifecycle.
For more information about the API operation to delete all lifecycle rules, see DeleteBucketLifecycle.