ABAP 调用HTTP上传附件

时间：2022-11-09 15:11:03

在SAP中调用第三方文件服务器的HTTP请求，将文件保存在文件服务器上，并返回保存的文件地址。
SAP保存返回的文件地址，通过浏览器进行访问。

2、需求实现

2.1、POSTMAN测试

通过POSTMAN测试成功，获取返回的文件地址

ABAP 调用HTTP上传附件

并且可以看到请求对应编程语言的示例代码

 ABAP 调用HTTP上传附件

2.2、代码示例

通过文件服务器URL创建http_client，设置类型为multipart/form-data，并传输请求参数

"-----------------------------@斌将军-----------------------------
TYPES: BEGIN OF ty_itab,
           raw(255) TYPE x,
         END OF ty_itab.

  DATA:lt_bin TYPE STANDARD TABLE OF ty_itab,
       ls_bin LIKE LINE OF lt_bin.

  DATA: lv_len         TYPE i, "发送报文长度
        lv_url         TYPE string, "接口地址
        lo_http_client TYPE REF TO if_http_client, "http客户端
        lo_part        TYPE REF TO if_http_entity,
        lv_value       TYPE string,
        lv_name        TYPE string,
        lv_file        TYPE string,
        lv_rec_json    TYPE string, "接收的JSON
        lv_code        TYPE i, "HTTP 返回状态
        lv_reason      TYPE string. " HTTP 状态描述

  DATA:lv_filelength TYPE  i,
       lv_xstring    TYPE xstring.

  DATA:lv_account TYPE string,
       lv_pass    TYPE string.

。。。。。。
"创建http客户端
  CALL METHOD cl_http_client=>create_by_url
    EXPORTING
      url                        = lv_url
    IMPORTING
      client                     = lo_http_client
    EXCEPTIONS
      argument_not_found         = 1
      plugin_not_active          = 2
      internal_error             = 3
      pse_not_found              = 4
      pse_not_distrib            = 5
      pse_errors                 = 6
      oa2c_set_token_error       = 7
      oa2c_missing_authorization = 8
      oa2c_invalid_config        = 9
      oa2c_invalid_parameters    = 10
      oa2c_invalid_scope         = 11
      oa2c_invalid_grant         = 12
      OTHERS                     = 13.
  IF sy-subrc <> 0.
    e_return-type = 'E'.
    e_return-message = '无法创建http client'.
    RAISE error.
  ENDIF.

  "设置http method 为POST
  CALL METHOD lo_http_client->request->set_header_field
    EXPORTING
      name  = '~request_method'
      value = 'POST'.

  "SET protocol version
  CALL METHOD lo_http_client->request->set_version(
    if_http_request=>co_protocol_version_1_1 ).

  "content type
  CALL METHOD lo_http_client->request->set_content_type
    EXPORTING
      content_type = 'multipart/form-data'.

  "用户名
  CALL METHOD lo_http_client->request->set_form_field
    EXPORTING
      name  = 'accessKey'
      value = lv_account. 

  "文件夹名称
  CALL METHOD lo_http_client->request->set_form_field
    EXPORTING
      name  = 'bucketName'
      value = 'sap'.

  "密码
  CALL METHOD lo_http_client->request->set_form_field
    EXPORTING
      name  = 'secretKey'
      value = lv_pass. "
"-----------------------------@斌将军-----------------------------

浏览器对应的编码和语言设置，可以参考浏览器中测试时，真实发送的请求参数

ABAP 调用HTTP上传附件

"-----------------------------@斌将军-----------------------------
"浏览器支持的 MIME 类型
  CALL METHOD lo_http_client->request->set_header_field
    EXPORTING
      name  = 'Accept'
      value = '*/*'.

  "浏览器支持的压缩编码
  CALL METHOD lo_http_client->request->set_header_field
    EXPORTING
      name  = 'Accept-Encoding'
      value = 'gzip, deflate'.

  "浏览器支持的语言
  CALL METHOD lo_http_client->request->set_header_field
    EXPORTING
      name  = 'Accept-Language'
      value = 'zh-CN,zh;q=0.9,de;q=0.8,en;q=0.7'.
"-----------------------------@斌将军-----------------------------

添加上传的文件，其中文件名需要进行URL编码，可避免文件的中文乱码

其中name="file" 对应POSTMAN请求参数中的file

"-----------------------------@斌将军-----------------------------
CALL METHOD lo_http_client->request->if_http_entity~set_formfield_encoding
    EXPORTING
      formfield_encoding = cl_http_request=>if_http_entity~co_encoding_raw.

  lo_part = lo_http_client->request->if_http_entity~add_multipart( ).

  "拼接上传的文件名，并将文件名转码
  lv_name = i_filename.
  lv_name = cl_http_utility=>escape_url( lv_name ).
  lv_value = 'form-data; name="file"; filename="' && lv_name && '";'.

  CALL METHOD lo_part->set_header_field
    EXPORTING
      name  = 'content-disposition'
*     value = 'form-data; name="file"; filename="11.txt";'.
      value = lv_value.

  CALL METHOD lo_part->set_content_type
    EXPORTING
      content_type = 'application/x-www-form-urlencoded'.
"-----------------------------@斌将军-----------------------------

上传本地文件为二进制，并转为xstring格式

"-----------------------------@斌将军-----------------------------
CALL FUNCTION 'GUI_UPLOAD'
    EXPORTING
      filename                = lv_file
      filetype                = 'BIN'
    IMPORTING
      filelength              = lv_filelength
    TABLES
      data_tab                = lt_bin
    EXCEPTIONS
      file_open_error         = 1
      file_read_error         = 2
      no_batch                = 3
      gui_refuse_filetransfer = 4
      invalid_type            = 5
      no_authority            = 6
      unknown_error           = 7
      bad_data_format         = 8
      header_not_allowed      = 9
      separator_not_allowed   = 10
      header_too_long         = 11
      unknown_dp_error        = 12
      access_denied           = 13
      dp_out_of_memory        = 14
      disk_full               = 15
      dp_timeout              = 16
      OTHERS                  = 17.
  IF sy-subrc <> 0.
    e_return-type = 'E'.
    e_return-message = '读取文件失败'.
    RAISE error.
  ENDIF.

  CALL FUNCTION 'SCMS_BINARY_TO_XSTRING'
    EXPORTING
      input_length = lv_filelength
    IMPORTING
      buffer       = lv_xstring
    TABLES
      binary_tab   = lt_bin
    EXCEPTIONS
      failed       = 1
      OTHERS       = 2.
"-----------------------------@斌将军-----------------------------

将文件流放入client中并发送，接收返回结果

"-----------------------------@斌将军-----------------------------
lv_len = xstrlen( lv_xstring ).

  CALL METHOD lo_part->set_data
    EXPORTING
      data   = lv_xstring
      offset = 0
      length = lv_len.

  "发送
  CALL METHOD lo_http_client->send
    EXCEPTIONS
      http_communication_failure = 1
      http_invalid_state         = 2
      http_processing_failed     = 3
      OTHERS                     = 4.
  IF sy-subrc <> 0.
    CALL METHOD lo_http_client->get_last_error
      IMPORTING
        message = DATA(lv_error_message).
    CALL METHOD lo_http_client->close.

    e_return-type = 'E'.
    e_return-message = '通信失败'.
    RAISE error.
  ENDIF.

  "接收
  CALL METHOD lo_http_client->receive
    EXCEPTIONS
      http_communication_failure = 1
      http_invalid_state         = 2
      http_processing_failed     = 3
      OTHERS                     = 9.
  IF sy-subrc <> 0.
    CALL METHOD lo_http_client->get_last_error
      IMPORTING
        message = lv_error_message.
    CALL METHOD lo_http_client->close.

    e_return-type = 'E'.
    e_return-message = '接收失败'.
    RAISE error.
  ENDIF.

  "提取返回字符串
  CLEAR:lv_code,lv_reason.
  CALL METHOD lo_http_client->response->get_status
    IMPORTING
      code   = lv_code
      reason = lv_reason.

  "获取返回的JSON
  CLEAR:lv_rec_json.
  lv_rec_json = lo_http_client->response->get_cdata( ).

  "关闭接口
  CALL METHOD lo_http_client->close.
"-----------------------------@斌将军-----------------------------

3、补充说明

3.1、文件类型

在设置上传文件的类型时需要注意

ABAP 调用HTTP上传附件

文件有对应的类型参数，例如：

TXT：text/plain

Excel：application/vnd.openxmlformats-officedocument.spreadsheetml.sheet

Word：application/vnd.openxmlformats-officedocument.wordprocessingml.document

PDF：application/pdf

PNG：image/png

应用程序：application/octet-stream

测试得出以下结论：（可能有出入，仅供参考）

1、如果上传文件时，设置了对应的参数，

1.1、且浏览器支持预览，则访问文件地址时，直接能在浏览器中显示文件的内容，比如：TXT、PDF、PNG等

1.2、如果浏览器不支持预览，则访问文件地址时，浏览器会自动下载对应的文件到本地，比如Excel、Word、应用程序等

2、如果上传文件时，没有设置对应的参数，比如直接设置application/x-www-form-urlencoded、application/octet-stream，就算是TXT文件，浏览器也不会支持预览，直接下载

3、如果上传文件时，没有设置正确的参数，比如Excel文件，设置了text/plain参数，则会导致文件识别失败，浏览器既不下载也不能正确预览

3.2、参数细节

关于参数中的q=0.8

ABAP 调用HTTP上传附件

 q:相对品质因数。它指定用户喜欢哪种语言，范围从0到1，默认为1。

该质量值表示用户对由该范围指定的语言的偏好的估计