C-SDK之如何实现上传文件(三)?

分步完成分片上传


分步完成分片上传的好处是灵活，一般的流程如下:

1. 初始化一个分片上传任务（oss_init_multipart_upload）
2. 逐个或并行上传分片（oss_upload_part_from_file）
3. 完成上传（oss_complete_multipart_upload）

1. void init_multipart_upload()
2. {
3.     aos_pool_t *p = NULL;
4.     aos_string_t bucket;
5.     aos_string_t object;
6.     aos_table_t *headers = NULL;
7.     aos_table_t *resp_headers = NULL;
8.     oss_request_options_t *options = NULL;
9.     aos_string_t upload_id;
10.     oss_upload_file_t *upload_file = NULL;
11.     aos_status_t *s = NULL;
12.     oss_list_upload_part_params_t *params = NULL;
13.     aos_list_t complete_part_list;
14.     oss_list_part_content_t *part_content = NULL;
15.     aos_pool_create(&p, NULL);
17.     /* 创建并初始化options */
18.     options = oss_request_options_create(p);
19.     init_options(options);
21.     /* 初始化参数 */
22.     headers = aos_table_make(p, 1);
23.     aos_str_set(&bucket, "<您的bucket名字>");
24.     aos_str_set(&object, "<您的object名字>");
26.     /* 初始化分片上传，获取一个上传ID */
27.     s = oss_init_multipart_upload(options, &bucket, &object,
28.                                   &upload_id, headers, &resp_headers);
30.     /* 判断是否初始化分片上传成功 */
31.     if (aos_status_is_ok(s)) {
32.         printf("Init multipart upload succeeded, upload_id:%.*s\n",
33.                upload_id.len, upload_id.data);
34.     } else {
35.         printf("Init multipart upload failed, upload_id:%.*s\n",
36.                upload_id.len, upload_id.data);
37.     }
39.     /* 上传每一个分片，代码参考下一节，这里省略*/
40.     /* 完成分片上传，代码参考后面章节，这里省略*/
42.     /* 释放资源*/
43.     aos_pool_destroy(p);
44. }

注：

• 返回结果中含有uplolad_id ，它是区分分片上传事件的唯一标识，在后面的操作中，我们将用到它。
• 上述代码只是演示如何初始化分片上传，只是部分代码，完整的代码参考下面的GitHub链接。
• 完整代码参考：GitHub
• 1.0.0版本中的参数顺序是…headers, upload_id…，2.0.0版本中的参数顺序是…upload_id，headers…

1. void multipart_upload_file()
2. {
3.     aos_pool_t *p = NULL;
4.     aos_string_t bucket;
5.     aos_string_t object;
6.     int is_cname = 0;
7.     aos_table_t *headers = NULL;
8.     aos_table_t *complete_headers = NULL;
9.     aos_table_t *resp_headers = NULL;
10.     oss_request_options_t *options = NULL;
11.     aos_string_t upload_id;
12.     oss_upload_file_t *upload_file = NULL;
13.     aos_status_t *s = NULL;
14.     oss_list_upload_part_params_t *params = NULL;
15.     aos_list_t complete_part_list;
16.     oss_list_part_content_t *part_content = NULL;
17.     oss_complete_part_content_t *complete_part_content = NULL;
18.     int part_num1 = 1;
19.     int part_num2 = 2;
21.     aos_pool_create(&p, NULL);
23.     /* 创建并初始化options */
24.     options = oss_request_options_create(p);
25.     init_options(options);
27.     /* 初始化参数 */
28.     headers = aos_table_make(p, 1);
29.     resp_headers = aos_table_make(options->pool, 5);
30.     aos_str_set(&bucket, "<您的bucket名字>");
31.     aos_str_set(&object, "<您的object名字>");
33.     /* 初始化分片上传，获取upload id，代码参考前面章节，这里省略*/
35.     /* 上传第一个分片 */
36.     upload_file = oss_create_upload_file(p);
37.     aos_str_set(&upload_file->filename, MULTIPART_UPLOAD_FILE_PATH);
38.     upload_file->file_pos = 0;
39.     upload_file->file_last = 200 * 1024; //200k
40.     s = oss_upload_part_from_file(options, &bucket, &object, &upload_id,
41.         part_num1, upload_file, &resp_headers);    
43.     /* 判断是否上传分片成功 */
44.     if (aos_status_is_ok(s)) {
45.         printf("Multipart upload from file succeeded\n");
46.     } else {
47.         printf("Multipart upload from file failed\n");
48.     }
50.     /* 上传第二个分片 */
51.     upload_file->file_pos = 200 *1024;//remain content start pos
52.     upload_file->file_last = get_file_size(MULTIPART_UPLOAD_FILE_PATH);
53.     s = oss_upload_part_from_file(options, &bucket, &object, &upload_id,
54.         part_num2, upload_file, &resp_headers);
56.     /* 判断是否上传分片成功 */
57.     if (aos_status_is_ok(s)) {
58.         printf("Multipart upload from file succeeded\n");
59.     } else {
60.         printf("Multipart upload from file failed\n");
61.     }
63.     /* 完成分片上传，代码参考下一章节，这里省略*/
65.     /* 释放资源*/
66.     aos_pool_destroy(p);
67. }

注：

• oss_upload_part_from_file接口要求除最后一个分片以外，其他的分片大小都要大于100KB。
• 分片号码的范围是1~10000。如果超出这个范围，OSS将返回InvalidArgument的错误码。
• 每次上传分片时都要把流定位到此次上传分片开头所对应的位置。
• 上述代码只是演示如何初始化分片上传，只是部分代码，完整的代码参考下面的GitHub链接。
• 完整代码参考：GitHub

1. void complete_multipart_upload()
2. {
3.     aos_pool_t *p = NULL;
4.     aos_string_t bucket;
5.     aos_string_t object;
6.     aos_table_t *complete_headers = NULL;
7.     aos_table_t *resp_headers = NULL;
8.     oss_request_options_t *options = NULL;
9.     aos_string_t upload_id;
10.     aos_status_t *s = NULL;
11.     oss_list_upload_part_params_t *params = NULL;
12.     aos_list_t complete_part_list;
13.     oss_list_part_content_t *part_content = NULL;
14.     oss_complete_part_content_t *complete_part_content = NULL;
16.     aos_pool_create(&p, NULL);
18.     /* 创建并初始化options */
19.     options = oss_request_options_create(p);
20.     init_options(options);
22.     /* 初始化参数 */
23.     headers = aos_table_make(p, 1);
24.     resp_headers = aos_table_make(options->pool, 5);
25.     aos_str_set(&bucket, "<您的bucket名字>");
26.     aos_str_set(&object, "<您的object名字>");
28.     /* 初始化分片上传，获取一个Upload Id，代码参考上面章节，这里省略*/
29.     /* 上传每个分片，代码参考上面章节，这里省略*/
31.     /* 获取已经上传的分片
32.      * 调用oss_complete_multipart_upload接口时需要每个分片的ETag值，这个值有两种获取途径：
33.      * 第一种是上传每个分片的时候，返回结果里面会包含这个分片的ETag值，可以保存下来，等后面使用；
34.      * 第二种是通过调用oss_list_upload_part接口获取已经上传的分片的ETag值。
35.      * 下面演示的是第二种方式
36.      */
37.     params = oss_create_list_upload_part_params(p);
38.     params->max_ret = 1000;
39.     aos_list_init(&complete_part_list);
40.     s = oss_list_upload_part(options, &bucket, &object, &upload_id,
41.                              params, &resp_headers);
43.     /* 判断是否获取分片列表成功 */
44.     if (aos_status_is_ok(s)) {
45.         printf("List multipart succeeded\n");
46.     } else {
47.         printf("List multipart failed\n");
48.     }
50.     aos_list_for_each_entry(part_content, &params->part_list, node) {
51.         complete_part_content = oss_create_complete_part_content(p);
52.         aos_str_set(&complete_part_content->part_number,
53.                     part_content->part_number.data);
54.         aos_str_set(&complete_part_content->etag, part_content->etag.data);
55.         aos_list_add_tail(&complete_part_content->node, &complete_part_list);
56.     }
58.     /* 完成分片上传 */
59.     s = oss_complete_multipart_upload(options, &bucket, &object, &upload_id,
60.             &complete_part_list, complete_headers, &resp_headers);
62.     /* 判断完成分片上传是否成功 */
63.     if (aos_status_is_ok(s)) {
64.         printf("Complete multipart upload from file succeeded, upload_id:%.*s\n",
65.                upload_id.len, upload_id.data);
66.     } else {
67.         printf("Complete multipart upload from file failed\n");
68.     }
70.     /* 释放资源 */
71.     aos_pool_destroy(p);
72. }

注：

• 2.0.0相对于1.0.0版本，oss_complete_multipart_upload接口增加了headers参数，用来在完成时修改headers值
• 完整代码参考：GitHub