本文介绍如何进行跨域资源共享。

跨域资源共享（Cross-origin resource sharing，简称CORS）允许Web端的应用程序访问不属于本域的资源。OSS提供跨域资源共享接口，方便您控制跨域访问的权限。

更多关于跨域资源共享的介绍，请参见开发指南中的设置跨域访问和API参考中PutBucketcors。

#include "oss_api.h"
#include "aos_http_io.h"
const char *endpoint = "<yourEndpoint>";
const char *access_key_id = "<yourAccessKeyId>";
const char *access_key_secret = "<yourAccessKeySecret>";
const char *bucket_name = "<yourBucketName>";
void init_options(oss_request_options_t *options)
{
    options->config = oss_config_create(options->pool);
    /* 用char*类型的字符串初始化aos_string_t类型。*/
    aos_str_set(&options->config->endpoint, endpoint);
    aos_str_set(&options->config->access_key_id, access_key_id);
    aos_str_set(&options->config->access_key_secret, access_key_secret);
    /* 是否使用了CNAME。0表示不使用。*/
    options->config->is_cname = 0;
    /* 用于设置网络相关参数，比如超时时间等。*/
    options->ctl = aos_http_controller_create(options->pool, 0);
}
int main(int argc, char *argv[])
{
    /* 在程序入口调用aos_http_io_initialize方法来初始化网络、内存等全局资源。*/
    if (aos_http_io_initialize(NULL, 0) != AOSE_OK) {
        exit(1);
    }
    /* 用于内存管理的内存池（pool），等价于apr_pool_t。其实现代码在apr库中。*/
    aos_pool_t *pool;
    /* 重新创建一个内存池，第二个参数是NULL，表示没有继承其它内存池。*/
    aos_pool_create(&pool, NULL);
    /* 创建并初始化options，该参数包括endpoint、access_key_id、acces_key_secret、is_cname、curl等全局配置信息。*/
    oss_request_options_t *oss_client_options;
    /* 在内存池中分配内存给options。*/
    oss_client_options = oss_request_options_create(pool);
    /* 初始化Client的选项oss_client_options。*/
    init_options(oss_client_options);
    /* 初始化参数。*/
    aos_string_t bucket;
    aos_table_t *resp_headers = NULL; 
    aos_status_t *resp_status = NULL;
    aos_list_t cors_rule_list;
    oss_cors_rule_t *cors_rule1 = NULL, *cors_rule2 = NULL;
    aos_str_set(&bucket, bucket_name);
    aos_list_init(&cors_rule_list);
    cors_rule1 = oss_create_cors_rule(pool);
    aos_list_add_tail(&cors_rule1->node, &cors_rule_list);
    oss_create_sub_cors_rule(pool, &cors_rule1->allowed_origin_list, "allowed_origin_1_1");
    oss_create_sub_cors_rule(pool, &cors_rule1->allowed_origin_list, "allowed_origin_1_1");
    oss_create_sub_cors_rule(pool, &cors_rule1->allowed_method_list, "PUT");
    oss_create_sub_cors_rule(pool, &cors_rule1->allowed_method_list, "GET");
    oss_create_sub_cors_rule(pool, &cors_rule1->allowed_head_list, "Authorization");
    oss_create_sub_cors_rule(pool, &cors_rule1->expose_head_list, "expose_head_1_1");
    oss_create_sub_cors_rule(pool, &cors_rule1->expose_head_list, "expose_head_1_1");
    cors_rule2 = oss_create_cors_rule(pool);
    aos_list_add_tail(&cors_rule2->node, &cors_rule_list);
    oss_create_sub_cors_rule(pool, &cors_rule2->allowed_origin_list, "allowed_origin_2_1");
    oss_create_sub_cors_rule(pool, &cors_rule2->allowed_origin_list, "allowed_origin_2_2");
    oss_create_sub_cors_rule(pool, &cors_rule2->allowed_method_list, "PUT");
    oss_create_sub_cors_rule(pool, &cors_rule2->allowed_method_list, "GET");
    oss_create_sub_cors_rule(pool, &cors_rule2->allowed_head_list, "Authorization");
    oss_create_sub_cors_rule(pool, &cors_rule2->expose_head_list, "expose_head_2_1");
    oss_create_sub_cors_rule(pool, &cors_rule2->expose_head_list, "expose_head_2_2");
    /* 设置跨域资源共享规则。*/
    resp_status = oss_put_bucket_cors(oss_client_options, &bucket, &cors_rule_list, &resp_headers);
    if (aos_status_is_ok(resp_status)) {
        printf("put bucket cors succeeded\n");
    } else {
        printf("put bucket cors failed\n");      
    }
    /* 释放内存池，相当于释放了请求过程中各资源分配的内存。*/
    aos_pool_destroy(pool);
    /* 释放之前分配的全局资源。*/
    aos_http_io_deinitialize();
    return 0;
}

#include "oss_api.h"
#include "aos_http_io.h"
const char *endpoint = "<yourEndpoint>";
const char *access_key_id = "<yourAccessKeyId>";
const char *access_key_secret = "<yourAccessKeySecret>";
const char *bucket_name = "<yourBucketName>";
void init_options(oss_request_options_t *options)
{
    options->config = oss_config_create(options->pool);
    /* 用char*类型的字符串初始化aos_string_t类型。*/
    aos_str_set(&options->config->endpoint, endpoint);
    aos_str_set(&options->config->access_key_id, access_key_id);
    aos_str_set(&options->config->access_key_secret, access_key_secret);
    /* 是否使用了CNAME。0表示不使用。*/
    options->config->is_cname = 0;
    /* 设置网络相关参数，比如超时时间等。*/
    options->ctl = aos_http_controller_create(options->pool, 0);
}
int main(int argc, char *argv[])
{
    /* 在程序入口调用aos_http_io_initialize方法来初始化网络、内存等全局资源。*/
    if (aos_http_io_initialize(NULL, 0) != AOSE_OK) {
        exit(1);
    }
    /* 用于内存管理的内存池（pool），等价于apr_pool_t。其实现代码在apr库中。*/
    aos_pool_t *pool;
    /* 重新创建一个内存池，第二个参数是NULL，表示没有继承其它内存池。*/
    aos_pool_create(&pool, NULL);
    /* 创建并初始化options，该参数包括endpoint、access_key_id、acces_key_secret、is_cname、curl等全局配置信息。*/
    oss_request_options_t *oss_client_options;
    /* 在内存池中分配内存给options。*/
    oss_client_options = oss_request_options_create(pool);
    /* 初始化Client的选项oss_client_options。*/
    init_options(oss_client_options);
    /* 初始化参数。*/
    aos_string_t bucket;
    aos_table_t *resp_headers = NULL; 
    aos_status_t *resp_status = NULL;
    aos_list_t cors_rule_list;
    oss_cors_rule_t *cors_rule = NULL;
    oss_sub_cors_rule_t *sub_cors_rule = NULL;
    aos_str_set(&bucket, bucket_name);
    /* 获取跨域资源共享规则。*/
    aos_list_init(&cors_rule_list);
    resp_status = oss_get_bucket_cors(oss_client_options, &bucket, &cors_rule_list, &resp_headers);
    if (aos_status_is_ok(resp_status)) {
        printf("get bucket cors succeeded\n");
        aos_list_for_each_entry(oss_cors_rule_t, cors_rule, &cors_rule_list, node) {
            printf("max_age_seconds: %d\n", cors_rule->max_age_seconds);
            aos_list_for_each_entry(oss_sub_cors_rule_t, sub_cors_rule, &cors_rule->allowed_origin_list, node) {
                printf("allowed_origin_list: %s \n", sub_cors_rule->rule.data);
            }
            aos_list_for_each_entry(oss_sub_cors_rule_t, sub_cors_rule, &cors_rule->allowed_method_list, node) {
                printf("allowed_method_list: %s \n", sub_cors_rule->rule.data);
            }
            aos_list_for_each_entry(oss_sub_cors_rule_t, sub_cors_rule, &cors_rule->allowed_head_list, node) {
                printf("allowed_head_list: %s \n", sub_cors_rule->rule.data);
            }
            aos_list_for_each_entry(oss_sub_cors_rule_t, sub_cors_rule, &cors_rule->expose_head_list, node) {
                printf("expose_head_list: %s \n", sub_cors_rule->rule.data);
            }
        }
    } else {
        printf("get bucket cors failed\n");      
    }
    /* 释放内存池，相当于释放了请求过程中各资源分配的内存。*/
    aos_pool_destroy(pool);
    /* 释放之前分配的全局资源。*/
    aos_http_io_deinitialize();
    return 0;
}

#include "oss_api.h"
#include "aos_http_io.h"
const char *endpoint = "<yourEndpoint>";
const char *access_key_id = "<yourAccessKeyId>";
const char *access_key_secret = "<yourAccessKeySecret>";
const char *bucket_name = "<yourBucketName>";
void init_options(oss_request_options_t *options)
{
    options->config = oss_config_create(options->pool);
    /* 用char*类型的字符串初始化aos_string_t类型。*/
    aos_str_set(&options->config->endpoint, endpoint);
    aos_str_set(&options->config->access_key_id, access_key_id);
    aos_str_set(&options->config->access_key_secret, access_key_secret);
    /* 是否使用了CNAME。0表示不使用。*/
    options->config->is_cname = 0;
    /* 设置网络相关参数，比如超时时间等。*/
    options->ctl = aos_http_controller_create(options->pool, 0);
}
int main(int argc, char *argv[])
{
    /* 在程序入口调用aos_http_io_initialize方法来初始化网络、内存等全局资源。*/
    if (aos_http_io_initialize(NULL, 0) != AOSE_OK) {
        exit(1);
    }
    /* 用于内存管理的内存池（pool），等价于apr_pool_t。其实现代码在apr库中。*/
    aos_pool_t *pool;
    /* 重新创建一个内存池，第二个参数是NULL，表示没有继承其它内存池。*/
    aos_pool_create(&pool, NULL);
    /* 创建并初始化options，该参数包括endpoint、access_key_id、acces_key_secret、is_cname、curl等全局配置信息。*/
    oss_request_options_t *oss_client_options;
    /* 在内存池中分配内存给options。*/
    oss_client_options = oss_request_options_create(pool);
    /* 初始化Client的选项oss_client_options。*/
    init_options(oss_client_options);
    /* 初始化参数。*/
    aos_string_t bucket;
    aos_table_t *resp_headers = NULL; 
    aos_status_t *resp_status = NULL;
    aos_str_set(&bucket, bucket_name);
    /* 删除跨域资源共享规则。*/
    resp_status = oss_delete_bucket_cors(oss_client_options, &bucket, &resp_headers);
    if (aos_status_is_ok(resp_status)) {
        printf("get bucket cors succeeded\n");
    } else {
        printf("get bucket cors failed\n");      
    }
    /* 释放内存池，相当于释放了请求过程中各资源分配的内存。*/
    aos_pool_destroy(pool);
    /* 释放之前分配的全局资源。*/
    aos_http_io_deinitialize();
    return 0;
}