SAP与OBS通讯接口架构及技术说明

目录

文章目录

  • SAP与OBS通讯接口架构及技术说明
    • 目录
    • 1. 业务背景
    • 2. 接口架构
    • 3. 接口实现
      • 3.1 计算签名
        • 3.1.1 签名算法的实现
          • 3.1.1.1 OBS 授权方式
          • 3.1.1.2 Header和URL中携带签名的区别
          • 3.1.1.3 对象
          • 3.1.1.4 签名算法实现
        • 3.1.2 PI接口
          • 3.1.2.1 创建PI接口和User-Defined Function
          • 3.1.2.2 PI代码实现
      • 3.2 文件操作
        • 3.2.1 附件上载 UPLOAD_ATTACHMENT
        • 3.2.2 附件下载 DOWNLOAD_ATTACHMENT
        • 3.2.3 附件删除 DELETE_ATTACHMENT
        • 3.2.4 文件内容下载 DOWNLOAD_FILE
        • 3.2.5 显示附件 DISPLAY_ATTACHMENT
        • 3.2.6 复制附件
          • 3.2.6.1 两步法：先下载再上载 COPY_ATTACHMENT_NEW
          • 3.2.6.2 一步法：直接调用OBS复制功能COPY_ATTACHMENT
          • 3.2.6.3 测试程序
      • 3.3 桶的基本操作
        • 3.3.1 列举桶内对象
          • 3.3.1.1 列举桶内对象采用GET方法
          • 3.3.1.2 计算签名
          • 3.3.1.3 设置HTTP头域
          • 3.3.1.4 设置url
          • 3.3.1.5 调用HTTP返回对象清单
          • 3.3.1.6 解析返回的XML文件
          • 3.3.1.7 源码实现
          • 3.3.1.8 测试程序

1. 业务背景

业务需求用文件传输来实现接口，或者需要将附件保存到服务器（照片、合同附件等等）。

常规的做法有两种:

  • 一种是搭建FTP/SFTP服务器。
    SAP封装了FTP函数来操作文件。 常用的FTP函数如下，

    FTP_CONNECT 连接FTP

    FTP_DISCONNECT 断开连接

    FTP_COMMAND 发送FTP命令

    FTP_COMMAND_LIST 发送多个FTP命令

    FTP_R3_TO_SERVER 将文件放到FTP

    FTP_SERVER_TO_R3 从FTP读取文件

    但对于SFTP，需要安全认证，目前ABAP不能直接访问SFTP，需借用PI或JAVA来实现。

  • 第二种是搭建文档服务器或存储服务器。使用HTTP RESTful访问（PUT、GET、DELETE等等）。 一般在访问前可以通过获取Token或签名的方式，来保证文件的安全访问。

本文介绍的华为云OBS（以下简称OBS），是华为云的对象存储服务。

2. 接口架构

对开发者来说，OBS提供了API和SDK的方式访问。由于ABAP代码不能引入JAR包，所以只能用API的方式。

OBS的访问需要先根据AK（访问密钥）和SK（私有访问密钥）计算签名，然后将签名放到HTTP请求中。

由于ABAP不能实现这个签名算法，所以我们需要一个能执行这段JAVA代码的环境来计算签名（当然，如果后续SAP支持这段算法计算的，也可以直接在SAP计算签名）。

假设有一个外围的JAVA系统能开启一个服务计算签名，这个问题就解决了。但目前没有这样的外围系统，所以我们借用PI的User-Defined Function（UDF)来说实现这段签名算法。

借用PI的UDF需要配置PI接口，但我们不需要跟外围系统进行交互， 所以PI的发送方和接受方都是SAP系统。

3. 接口实现

3.1 计算签名

3.1.1 签名算法的实现

3.1.1.1 OBS 授权方式

​ OBS授权方式主要有4种，详细可参考华为云官方文档。https://support.huaweicloud.com/api-obs/obs_04_0008.html

  • 1. 用户签名验证
  • 2. Header中携带签名
  • 3. URL中携带签名
  • 4. 基于浏览器上传的表单中携带签名

本次接口使用第2种和第3种。

3.1.1.2 Header和URL中携带签名的区别

  • 签名算法不一样

    • URL中携带签名

      需要传入有效期（单位秒），当前系统时间的秒数+传入的有效期作为计算签名的参数

      StringToSign =      HTTP-Verb + "\n" +        Content-MD5 + "\n" +        Content-Type + "\n" +        Expires + "\n" +        CanonicalizedHeaders +   CanonicalizedResource;

    • Header中携带签名

      取当前系统时间转换成GMT格式作为计算签名的参数

      StringToSign =     HTTP-Verb + "\n" +     Content-MD5 + "\n" +     Content-Type + "\n" +     Date + "\n" +     CanonicalizedHeaders + CanonicalizedResource

  • 创建HTTP请求时，授权信息放的位置不一样

    • URL中携带签名，授权信息作为URL的参数：

      HOST/ObjectKey” />

      在消息类型映射Message Mapping中引用自定义的User-Defined Function

      3.1.2.2 PI代码实现
      • 创建一个公共类ZCL_OBS，包含SAP与OBS接口通讯的所有操作
      • 在S4创建自定义签名信息表ZOBST_SIGNTRUE,存储PI返回的签名信息
      • 实现PI接口代理类：
        在类ZCL_OBS中创建获取签名的方法GET_SIGNTRUE，
        • 先调用PI Outbound的接口，将计算签名所需的信息发送到PI。
        • 在PI Inbound接口中，将返回的签名信息存到表ZOBS_SIGNTRUE；
        • 在方法GET_SIGNTRUE中取出返回的签名信息。
         METHOD get_signtrue.    DATA: lo_proxy_out    TYPE REF TO zpico_si_bc000501_erp2erp_syn,          ls_output       TYPE zpimt_bc000501_req_out,          ls_input        TYPE zpimt_bc000501_res,          ls_bc000501_req TYPE zpidt_bc000501_req,          lv_message      TYPE bapi_msg,          lv_uuid         TYPE sysuuid_c32,          lv_seconds      TYPE p LENGTH 3 DECIMALS 1 VALUE '0.1'.    CLEAR: ls_output,           ls_input,           es_return,           rs_signtrue,           lv_uuid.    " 1. 根据桶的配置获取AK/SK    CLEAR: ms_obs_config.    CALL METHOD get_obs_config      EXPORTING        iv_bucketname = is_signtrue_req-bucketname*       iv_httpmethod = is_signtrue_req-httpmethod      IMPORTING        es_obs_config = ms_obs_config.    IF ms_obs_config IS INITIAL.      "桶&1方法&2的签名配置丢失或未激活，请检查表ZOBS_CONFIG      MESSAGE e003 WITH is_signtrue_req-bucketname is_signtrue_req-httpmethod INTO lv_message.      es_return = zcl_message=>convert_syst_to_bapiret2( ).      RETURN.    ELSE.      "insert begin by kevin.liang on 20210401      "AK/SK包含空格会导致计算签名出错      CONDENSE: ms_obs_config-obsak ,                ms_obs_config-obssk .      "insert end by kevin.liang on 20210401    ENDIF.    "2. 调用PI计算签名    CLEAR: ls_bc000501_req.    "获取UUID    TRY .        CALL METHOD cl_system_uuid=>if_system_uuid_static~create_uuid_c32          RECEIVING            uuid = lv_uuid.      CATCH cx_uuid_error.    ENDTRY.    ls_bc000501_req-uuid                     = lv_uuid                             ."请求PI的唯一码    ls_bc000501_req-http_method              = mv_http_method          ."http请求操作方法,PUT/GET/DELETE    ls_bc000501_req-access_key               = ms_obs_config-obsak                 ."访问密钥AK    ls_bc000501_req-security_key             = ms_obs_config-obssk                 ."私有访问密钥SK    ls_bc000501_req-author_type              = is_signtrue_req-authortype          ."签名授权方式(Header中携带签名、URL中携带签名)    ls_bc000501_req-expires                  = is_signtrue_req-expires             ."有效期    ls_bc000501_req-content_type             = is_signtrue_req-contenttype         ."Content-Type内容类型    ls_bc000501_req-content_md5              = is_signtrue_req-contentmd5          ."Content-MD5    ls_bc000501_req-canonicalize_headers     = is_signtrue_req-canonicalizeheaders ."HTTP请求头域中的OBS请求头字段    ls_bc000501_req-canonicalize_resource    = is_signtrue_req-canonicalizeresource."HTTP请求所指定的OBS资源    "调用PI计算签名    CALL METHOD calc_signtrue      EXPORTING        is_bc000501_req = ls_bc000501_req      IMPORTING        es_return       = es_return      RECEIVING        rs_signtrue     = rs_signtrue.    ms_signtrue =  rs_signtrue.  ENDMETHOD.

      3.2 文件操作

      ​ 创建配置表ZOBS_CONFIG, 用来配置每个桶不同请求方法的AK、SK以及日志保留天数等等。

      ​ 在类ZCL_OBS中创建6基本操作方式,授权方式默认使用header中携带签名;

      1. [附件上载UPLOAD_ATTACHMENT](#3.2.1 附件上载 UPLOAD_ATTACHMENT)>;

      2. [附件下载DOWNLOAD_ATTACHMENT](#3.2.2 附件下载 DOWNLOAD_ATTACHMENT) ;

      3. [附件删除DELETE_ATTACHMENT](#3.2.3 附件删除 DELETE_ATTACHMENT)；

      4. 另外创建直接[下载文件内容的方法DOWNLOAD_FILE](#3.2.4 文件内容下载 DOWNLOAD_FILE)，采用**[URL携带签名的方式授权](#3.1.1.1 OBS 授权方式)**；

      5. [显示附件 DISPLAY_ATTACHMENT](#3.2.5 显示附件 DISPLAY_ATTACHMENT)

      6. [复制附件](#3.2.6 复制附件)

      3.2.1 附件上载 UPLOAD_ATTACHMENT

      • 附件上载使用PUT方法;

      • 调用计算签名方法；

      • 创建HTTP客户端，HOST需要包含Object Key；

      • 设置HTTP头域（Header）；

      • 将本地文件转换成XSTRING，并填充到HTTP Client；

      • 发送请求，并提取返回的结果。

          METHOD upload_attachment.    CALL METHOD upload_object      EXPORTING        iv_bucketname = iv_bucketname        iv_filename   = iv_filename        iv_data       = iv_data        iv_objectkey  = iv_objectkey      IMPORTING        es_return     = es_return        es_result     = es_result.    "记录日志    logging_obslog( is_return = es_return is_result = es_result ).    "日志自动清理    clear_obslog( ).  ENDMETHOD.
            METHOD upload_object.    DATA: lv_objectkey TYPE string.    DATA: lv_data       TYPE xstring,          lv_filelength TYPE i,          lv_message    TYPE bapi_msg.    "设置桶信息    set_bucket( iv_bucketname = iv_bucketname iv_objectkey = iv_objectkey ).    "设置OBS操作    set_action( c_action_upload ).    CLEAR: lv_objectkey.    lv_objectkey = iv_objectkey.    CALL METHOD adjust_objectkey      IMPORTING        es_return    = es_return      CHANGING        cv_objectkey = lv_objectkey.    IF es_return-type NA 'EAX'.      "获取OBS的签名      CLEAR:ms_signtrue_req         ,            es_return               ,            es_result               .      ms_signtrue_req-bucketname             = iv_bucketname.      ms_signtrue_req-httpmethod             = mv_http_method.      ms_signtrue_req-authortype             = c_authortype_header.      ms_signtrue_req-contenttype            = c_contenttype_bin .      ms_signtrue_req-contentmd5             = ''.      ms_signtrue_req-canonicalizeheaders    = ''.      ms_signtrue_req-canonicalizeresource   = '/' && iv_bucketname && lv_objectkey.      CALL METHOD get_signtrue        EXPORTING          is_signtrue_req = ms_signtrue_req        IMPORTING          es_return       = es_return.    ENDIF.    IF es_return-type NA 'EAX'.      "上载文件      IF iv_filename IS NOT INITIAL.        CALL METHOD gui_upload          EXPORTING            iv_filename   = iv_filename          IMPORTING            ev_filelength = lv_filelength          RECEIVING            rv_data       = lv_data          EXCEPTIONS            error         = 1            OTHERS        = 2.        IF sy-subrc  0.          es_return = zcl_message=>convert_syst_to_bapiret2( ).        ENDIF.      ELSEIF iv_data IS NOT INITIAL.        lv_data       = iv_data.        lv_filelength = xstrlen( lv_data ).      ELSE.        "上载内容不能为空        MESSAGE e015 INTO lv_message.        es_return = zcl_message=>convert_syst_to_bapiret2( ).      ENDIF.      IF es_return-type NA 'EAX'.        "采用HTTP Client访问OBS        call_obs_httpclient( EXPORTING iv_objectkey = lv_objectkey                                       iv_data      = lv_data       "二进制数据                                       iv_length    = lv_filelength                             IMPORTING es_return    = es_return                                       es_result    = es_result     ).        IF es_result-code = 200.          "附件上载成功，ObjectKey为&1.          MESSAGE s005 WITH iv_objectkey INTO lv_message.          es_return = zcl_message=>convert_syst_to_bapiret2( ).        ELSE.          "附件上载失败，错误原因：&1&2          MESSAGE e006 WITH es_result-code  es_result-reason INTO lv_message.          es_return = zcl_message=>convert_syst_to_bapiret2( ).        ENDIF.      ENDIF.    ENDIF.  ENDMETHOD.

      • 测试程序ZOBS_DEMO_ATTCH_UPLOAD

        *&---------------------------------------------------------------------**& Report ZOBS_ATTCH_UPLOAD_TEST*&---------------------------------------------------------------------**&*&---------------------------------------------------------------------*REPORT zobs_demo_attch_upload.SELECTION-SCREEN BEGIN OF BLOCK b1 WITH FRAME TITLE TEXT-s01.  PARAMETERS: p_bucket TYPE zzbucket_obs.  PARAMETERS: p_file TYPE rlgrap-filename MEMORY ID zfilename.SELECTION-SCREEN END OF BLOCK b1.AT SELECTION-SCREEN ON VALUE-REQUEST FOR p_file.  PERFORM frm_select_file CHANGING p_file.START-OF-SELECTION.  "上载文件  PERFORM frm_upload_file.*&---------------------------------------------------------------------**& Form frm_upload_file*&---------------------------------------------------------------------**& text*&---------------------------------------------------------------------**& -->  p1        text*& <--  p2        text*&---------------------------------------------------------------------*FORM frm_upload_file .  DATA: lo_obs       TYPE REF TO  zcl_obs,        lv_filename  TYPE string,        lv_objectkey TYPE string.  lv_filename = p_file.    CALL FUNCTION 'SO_SPLIT_FILE_AND_PATH'    EXPORTING      full_name     = lv_filename    IMPORTING      stripped_name = lv_objectkey*     FILE_PATH     =    EXCEPTIONS      x_error       = 1      OTHERS        = 2.  IF sy-subrc  0.* Implement suitable error handling here  ENDIF.  lv_objectkey = '/sapdemo/' && sy-datum && '/' && lv_objectkey.  CREATE OBJECT lo_obs.  CALL METHOD lo_obs->upload_attachment    EXPORTING      iv_bucketname = p_bucket      iv_filename   = lv_filename      iv_objectkey  = lv_objectkey*     iv_expires    = 3600    IMPORTING      es_return     = DATA(ls_return).    IF ls_return IS NOT INITIAL..      MESSAGE ID ls_return-id            TYPE ls_return-type          NUMBER ls_return-number            WITH ls_return-message_v1                 ls_return-message_v2                 ls_return-message_v3                 ls_return-message_v4.    ENDIF.ENDFORM.*&---------------------------------------------------------------------**& Form frm_select_file*&---------------------------------------------------------------------**& text*&---------------------------------------------------------------------**& -->  p1        text*& file_open_dialog    EXPORTING      window_title            = lv_title*      file_filter             = 'Excel(*.xlsx)|*.xlsx|Excel(*.xls)|*.xls'    CHANGING      file_table              = lt_filetable      rc                      = lv_subrc    EXCEPTIONS      file_open_dialog_failed = 1      cntl_error              = 2      error_no_gui            = 3      not_supported_by_gui    = 4      OTHERS                  = 5.  IF sy-subrc EQ 0.    LOOP AT lt_filetable INTO ls_filetable.      cv_file = ls_filetable-filename.    ENDLOOP.  ENDIF.ENDFORM.

      3.2.2 附件下载 DOWNLOAD_ATTACHMENT

      附件下载，FTYPE参数默认是BIN，返回二进制格式;如果需要[直接返回文本内容](#3.2.4 文件内容下载 DOWNLOAD_FILE)，则赋值为TEXT

      • 附件上载使用GET方法;

      • 调用计算签名方法；

      • 创建HTTP客户端，HOST需要包含Object Key；

      • 设置HTTP头域（Header）；

      • 发送请求；

      • 获取返回的结果，并将返回的数据XSTRING下载到本地。

           METHOD download_attachment.    CALL METHOD download_object      EXPORTING        iv_bucketname       = iv_bucketname        iv_objectkey        = iv_objectkey        iv_filetype         = iv_filetype        iv_direct_down      = iv_direct_down        iv_newline          = iv_newline        iv_default_filename = iv_default_filename      IMPORTING        es_return           = es_return        es_result           = es_result.    "记录日志    logging_obslog( is_return = es_return is_result = es_result ).    "日志自动清理    clear_obslog( ).  ENDMETHOD.
          METHOD download_object.    DATA: lv_message    TYPE bapi_msg.    DATA: lv_filename    TYPE string,          lv_extension   TYPE string,          lv_objectkey   TYPE string,          lv_user_action TYPE i,          lv_action      TYPE zzaction_obs.    DATA:lt_extension TYPE TABLE OF string,         lv_lines     TYPE i.    "设置桶信息    set_bucket( iv_bucketname = iv_bucketname iv_objectkey = iv_objectkey ).    "设置OBS操作    set_action( c_action_download ).    CLEAR: lv_objectkey.    lv_objectkey = iv_objectkey.    CALL METHOD adjust_objectkey      IMPORTING        es_return    = es_return      CHANGING        cv_objectkey = lv_objectkey.    IF es_return-type CA 'EAX'.      RETURN.    ENDIF.    "获取OBS的签名    CLEAR:ms_signtrue_req         ,          es_return               ,          es_result               .    ms_signtrue_req-bucketname             = iv_bucketname.    ms_signtrue_req-httpmethod             = mv_http_method.    ms_signtrue_req-authortype             = c_authortype_header.    ms_signtrue_req-contenttype            = c_contenttype_bin .    ms_signtrue_req-contentmd5             = ''.    ms_signtrue_req-canonicalizeheaders    = ''.    ms_signtrue_req-canonicalizeresource   = '/' && iv_bucketname && lv_objectkey.    CALL METHOD get_signtrue      EXPORTING        is_signtrue_req = ms_signtrue_req      IMPORTING        es_return       = es_return.    IF es_return-type CA 'EAX'.      RETURN.    ENDIF.    "采用HTTP Client访问OBS    call_obs_httpclient( EXPORTING iv_objectkey = lv_objectkey                         IMPORTING es_return    = es_return                                   es_result    = es_result     ).    IF es_result-code = 200.      "附件二进制下载      IF iv_direct_down IS NOT INITIAL AND iv_filetype = 'BIN'.*         取得OBS key的文件名        "根据Object key设置默认文件名        CALL METHOD get_default_filename          EXPORTING            iv_objectkey = iv_objectkey          IMPORTING            ev_filename  = lv_filename            ev_extension = lv_extension.        IF iv_default_filename IS NOT INITIAL.          "使用OBS Key的后半部分作为文件名          lv_filename = iv_default_filename. "使用外部传入的文件名        ENDIF.        CALL METHOD file_save_dialog          EXPORTING            default_extension = lv_extension            default_file_name = lv_filename          CHANGING            fullpath          = lv_filename            user_action       = lv_user_action          EXCEPTIONS            error             = 1            OTHERS            = 2.        IF sy-subrc  0 OR lv_user_action = 9.          es_return = zcl_message=>convert_syst_to_bapiret2( ).          RETURN.        ENDIF.*       判断后缀名是否与服务器文件名一致        REFRESH: lt_extension .        SPLIT lv_filename AT '.' INTO TABLE lt_extension .        CLEAR: lv_lines.        DESCRIBE TABLE lt_extension LINES lv_lines.        IF lv_lines > 0.          READ TABLE lt_extension INTO DATA(lv_extension_t) INDEX lv_lines.          IF sy-subrc EQ 0.            IF lv_extension_t  lv_extension.              CONCATENATE lv_filename '.' lv_extension INTO lv_filename.            ENDIF.          ELSE.            CONCATENATE lv_filename '.' lv_extension INTO lv_filename.          ENDIF.        ENDIF.        CALL METHOD gui_download          EXPORTING            iv_filename = lv_filename            iv_data     = es_result-rawbizdata          EXCEPTIONS            error       = 1            OTHERS      = 2.      ELSEIF iv_filetype = 'TEXT'."直接提取文本内容        IF iv_newline IS NOT INITIAL.          "LF换行          SPLIT es_result-bizdata AT cl_abap_char_utilities=>newline INTO TABLE es_result-data[].        ELSE.          "CR_LF换行          SPLIT es_result-bizdata AT cl_abap_char_utilities=>cr_lf INTO TABLE es_result-data[].        ENDIF.      ENDIF.      "附件下载成功，ObjectKey为&1.      MESSAGE s009 WITH iv_objectkey INTO lv_message.      es_return = zcl_message=>convert_syst_to_bapiret2( ).    ELSE.      "附件下载失败，错误原因：&1&2      MESSAGE e010 WITH es_result-code  es_result-reason INTO lv_message.      es_return = zcl_message=>convert_syst_to_bapiret2( ).    ENDIF.  ENDMETHOD.

      • 测试程序ZOBS_DEMO_ATTCH_DOWNLOAD

        *&---------------------------------------------------------------------**& Report ZOBS_ATTCH_DOWNLOAD_TEST*&---------------------------------------------------------------------**&*&---------------------------------------------------------------------*REPORT zobs_demo_attch_download.SELECTION-SCREEN BEGIN OF BLOCK b1 WITH FRAME TITLE TEXT-s01.  PARAMETERS: p_bucket TYPE zzbucket_obs DEFAULT 'mrm-attachment'.  PARAMETERS: p_objkey TYPE zzobjectkey_obs .  PARAMETERS: p_ftype  TYPE char10 DEFAULT 'BIN'.  SELECTION-SCREEN COMMENT 50(50) TEXT-001 FOR FIELD p_ftype  ."默认BIN,直接下载文件内容TEXTSELECTION-SCREEN END OF BLOCK b1.START-OF-SELECTION.  "下载文件  PERFORM frm_download_attachment.*&---------------------------------------------------------------------**& Form frm_download_attachment*&---------------------------------------------------------------------**& text*&---------------------------------------------------------------------**& -->  p1        text*& download_attachment      EXPORTING        iv_bucketname = p_bucket        iv_objectkey  = lv_objectkey      IMPORTING        es_return     = ls_return.  ELSE.    CALL METHOD lo_obs->download_attachment      EXPORTING        iv_bucketname = p_bucket        iv_objectkey  = lv_objectkey        iv_filetype   = 'TEXT'        iv_newline    = 'X'      IMPORTING        es_return     = ls_return        es_result     = DATA(ls_result).    cl_demo_output=>display( data = ls_result-data ).  ENDIF.  IF ls_return IS NOT INITIAL..    MESSAGE ID ls_return-id          TYPE 'S'        NUMBER ls_return-number          WITH ls_return-message_v1               ls_return-message_v2               ls_return-message_v3               ls_return-message_v4 DISPLAY LIKE ls_return-type.  ENDIF.ENDFORM.

      ​

      3.2.3 附件删除 DELETE_ATTACHMENT

      • 附件上载使用DELETE方法;

      • 调用计算签名方法GET_SIGNTRUE；

      • 创建HTTP客户端，HOST需要包含Object Key；

      • 设置HTTP头域（Header）；

      • 发送请求，根据状态码=204判断文件是否删除成功（备注：如果删除的对象不存在，删除也是返回204）。

           METHOD delete_attachment.    CALL METHOD delete_object      EXPORTING        iv_bucketname = iv_bucketname        iv_objectkey  = iv_objectkey      IMPORTING        es_return     = es_return        es_result     = es_result.    "记录日志    logging_obslog( is_return = es_return is_result = es_result ).    "日志自动清理    clear_obslog( ).  ENDMETHOD.
          METHOD DELETE_OBJECT.    DATA: lv_objectkey TYPE string,          lv_message   TYPE bapi_msg.    "设置桶信息    set_bucket( iv_bucketname = iv_bucketname iv_objectkey = iv_objectkey ).    "设置OBS操作    set_action( c_action_delete ).    CLEAR: lv_objectkey.    lv_objectkey = iv_objectkey.    CALL METHOD adjust_objectkey      IMPORTING        es_return    = es_return      CHANGING        cv_objectkey = lv_objectkey.    IF es_return-type NA 'EAX'.      "获取OBS的签名      CLEAR:ms_signtrue_req         ,            es_return               ,            es_result               .      ms_signtrue_req-bucketname             = iv_bucketname.      ms_signtrue_req-httpmethod             = mv_http_method.      ms_signtrue_req-authortype             = c_authortype_header.      ms_signtrue_req-contenttype            = c_contenttype_bin .      ms_signtrue_req-contentmd5             = ''.      ms_signtrue_req-canonicalizeheaders    = ''.      ms_signtrue_req-canonicalizeresource   = '/' && iv_bucketname && lv_objectkey.      CALL METHOD get_signtrue        EXPORTING          is_signtrue_req = ms_signtrue_req        IMPORTING          es_return       = es_return.    ENDIF.    IF es_return-type NA 'EAX'.      "采用HTTP Client访问OBS      call_obs_httpclient( EXPORTING iv_objectkey = lv_objectkey                           IMPORTING es_return    = es_return                                     es_result    = es_result     ).      IF es_result-code = 204. "        "附件删除成功，ObjectKey为&1.        MESSAGE s007 WITH iv_objectkey INTO lv_message.        es_return = zcl_message=>convert_syst_to_bapiret2( ).      ELSE.        "附件删除失败，错误原因：&1&2        MESSAGE e008 WITH es_result-code  es_result-reason INTO lv_message.        es_return = zcl_message=>convert_syst_to_bapiret2( ).      ENDIF.    ENDIF.  ENDMETHOD.

      • 测试程序ZOBS_DEMO_ATTCH_DELETE

        *&---------------------------------------------------------------------**& Report ZOBS_DEMO_ATTCH_DELETE*&---------------------------------------------------------------------**&*&---------------------------------------------------------------------*REPORT zobs_demo_attch_delete.SELECTION-SCREEN BEGIN OF BLOCK b1 WITH FRAME TITLE TEXT-s01.  PARAMETERS: p_bucket TYPE zzbucket_obs .  PARAMETERS: p_objkey TYPE zzobjectkey_obs .SELECTION-SCREEN END OF BLOCK b1.START-OF-SELECTION.  "上载文件  PERFORM frm_delete_attachment .*&---------------------------------------------------------------------**& Form frm_delete_attachment*&---------------------------------------------------------------------**& text*&---------------------------------------------------------------------**& -->  p1        text*& delete_attachment    EXPORTING      iv_bucketname = p_bucket      iv_objectkey  = lv_objectkey    IMPORTING      es_return     = ls_return      es_result     = DATA(ls_result).  IF ls_return IS NOT INITIAL..    MESSAGE ID ls_return-id          TYPE ls_return-type        NUMBER ls_return-number          WITH ls_return-message_v1               ls_return-message_v2               ls_return-message_v3               ls_return-message_v4.  ENDIF.ENDFORM.

      3.2.4 文件内容下载 DOWNLOAD_FILE

      此功能可以使用[附件下载](#3.2.2 附件下载 DOWNLOAD_ATTACHMENT )功能实现，只需要将FTYPE参数赋值为TEXT即可

        1. 直接下载Text文件内容，请求方法使用GET;
        1. 调用计算签名方法GET_SIGNTRUE*（采用URL中携带签名的方式计算签名）*；
        1. 创建HTTP客户端，HOST需要包含Object Key和授权信息；
        1. 设置HTTP头域（Header），不包含授权信息；
        1. 发送请求，根据状态码=200判断文件是否下载成功。
        1. 将文件内容转换成String的内表*（根据传入的参数，决定Windows/linux的换行符）*
        1. 源码实现
            METHOD download_file.    DATA:  lv_objectkey TYPE string.    "设置桶信息    set_bucket( iv_bucketname = iv_bucketname iv_objectkey = iv_objectkey ).    "设置OBS操作    set_action( c_action_download ).    "格式化对象Key    CLEAR: lv_objectkey.    lv_objectkey = iv_objectkey.    CALL METHOD adjust_objectkey      IMPORTING        es_return    = es_return      CHANGING        cv_objectkey = lv_objectkey.    IF es_return-type CA 'EAX'.      "记录日志      logging_obslog( is_return = es_return is_result = es_result ).      RETURN.    ENDIF.    DO 50 TIMES.      "获取OBS的签名      CLEAR:ms_signtrue_req         ,            es_return               ,            es_result               .      ms_signtrue_req-bucketname             = iv_bucketname.      ms_signtrue_req-httpmethod             = mv_http_method.      ms_signtrue_req-authortype             = c_authortype_url.      ms_signtrue_req-contenttype            = c_contenttype_bin .      ms_signtrue_req-contentmd5             = ''.      ms_signtrue_req-canonicalizeheaders    = ''.      ms_signtrue_req-canonicalizeresource   = '/' && iv_bucketname && lv_objectkey.      CALL METHOD get_signtrue        EXPORTING          is_signtrue_req = ms_signtrue_req        IMPORTING          es_return       = es_return.      IF es_return-type CA 'EAX'.        "记录日志        logging_obslog( is_return = es_return is_result = es_result ).        RETURN.      ENDIF.      "采用HTTP Client访问OBS      call_obs_httpclient( EXPORTING iv_objectkey = lv_objectkey                           IMPORTING es_return    = es_return                                     es_result    = es_result     ).      IF es_result-code = 200.        es_return-type       = 'S'.        IF iv_newline IS NOT INITIAL.          "LF换行          SPLIT es_result-bizdata AT cl_abap_char_utilities=>newline INTO TABLE es_result-data[].        ELSE.          "CR_LF换行          SPLIT es_result-bizdata AT cl_abap_char_utilities=>cr_lf INTO TABLE es_result-data[].        ENDIF.        EXIT.      ELSEIF es_result-code = 404." Connection Refused 网络不通        es_return-type       = 'E'.        EXIT.      ELSE.        CLEAR: es_return.        es_return-type       = 'E'.        WAIT UP TO '0.1' SECONDS.      ENDIF.    ENDDO.    "记录日志    logging_obslog( is_return = es_return is_result = es_result ).    "日志自动清理    clear_obslog( ).  ENDMETHOD.

      • 测试程序 ZOBS_DEMO_TEXTFILE_DOWNLOAD

        *&---------------------------------------------------------------------**& Report ZOBS_ATTCH_DOWNLOAD_TEST*&---------------------------------------------------------------------**&*&---------------------------------------------------------------------*REPORT zobs_demo_textfile_download.SELECTION-SCREEN BEGIN OF BLOCK b1 WITH FRAME TITLE TEXT-s01.  PARAMETERS: p_bucket TYPE zzbucket_obs.  PARAMETERS: p_objkey TYPE zzobjectkey_obs .SELECTION-SCREEN END OF BLOCK b1.START-OF-SELECTION.  "下载文件  PERFORM frm_download_file.*&---------------------------------------------------------------------**& Form frm_download_file*&---------------------------------------------------------------------**& text*&---------------------------------------------------------------------**& -->  p1        text*& download_file    EXPORTING      iv_bucketname = p_bucket*     iv_httpmethod = 'GET'      iv_objectkey  = lv_objectkey*     iv_expires    = 3600*     iv_newline    = 'X'    IMPORTING      es_return     = ls_return      es_result     = DATA(ls_result).  IF ls_return IS NOT INITIAL..    MESSAGE ID ls_return-id          TYPE ls_return-type        NUMBER ls_return-number          WITH ls_return-message_v1               ls_return-message_v2               ls_return-message_v3               ls_return-message_v4.  ENDIF.  IF ls_return-type = 'S'.    cl_demo_output=>display( data = ls_result-data ).  ENDIF.ENDFORM.

      3.2.5 显示附件 DISPLAY_ATTACHMENT

      *此功能可以使用[附件下载](#3.2.2 附件下载 DOWNLOAD_ATTACHMENT )功能实现，将文件下载的二进制用HTML、OLE控件显示出来

        1. 调用计算签名方法GET_SIGNTRUE*（采用Header中携带签名的方式计算签名）*；

        2. 创建HTTP客户端，HOST需要包含Object Key和授权信息；

        3. 设置HTTP头域（Header），包含授权信息；

        4. 发送请求，根据状态码=200判断文件是否下载成功。

        5. 将文件内容转换成String的内表 (根据传入的参数，决定Windows/linux的换行符）

        6. 源码实现

            METHOD display_attachment.    DATA: lv_type     TYPE text20,          lv_subtype  TYPE text20,          lv_filename TYPE string.    "下载附件    CALL METHOD download_object      EXPORTING        iv_bucketname  = iv_bucketname        iv_objectkey   = iv_objectkey        iv_filetype    = 'BIN'        iv_direct_down = ''      IMPORTING        es_return      = es_return        es_result      = DATA(ls_result).    IF es_return-type CA 'EAX'.      RETURN.    ENDIF.    "显示附件    DATA(lv_apptype) = get_application_type( EXPORTING                                               iv_dockey  = iv_objectkey                                             IMPORTING                                               ex_type    = lv_type                                               ex_subtype = lv_subtype ).    IF lv_type = 'text'.      CALL METHOD zcl_obs=>text_convert        CHANGING          cv_data = ls_result-rawbizdata.    ENDIF.    CASE lv_apptype.      WHEN app_type_html.        IF iv_dialog IS INITIAL.          CALL FUNCTION 'ZFM_OBS_DISPLAY_HTML'            EXPORTING              iv_data     = ls_result-rawbizdata              iv_type     = lv_type              iv_subtype  = lv_subtype              iv_filename = iv_objectkey.        ELSE.          CALL METHOD html_show            EXPORTING              iv_data     = ls_result-rawbizdata              iv_type     = lv_type              iv_subtype  = lv_subtype              iv_filename = iv_objectkey.        ENDIF.      WHEN app_type_ole.        IF iv_dialog IS INITIAL.          CALL FUNCTION 'ZFM_OBS_DISPLAY_OLE'            EXPORTING              iv_data     = ls_result-rawbizdata              iv_type     = lv_type              iv_subtype  = lv_subtype              iv_filename = iv_objectkey.        ELSE.          CALL METHOD ole_show            EXPORTING              iv_data     = ls_result-rawbizdata              iv_type     = lv_type              iv_subtype  = lv_subtype              iv_filename = iv_objectkey.        ENDIF.      WHEN OTHERS.        MESSAGE i000 WITH '不支持打开此类型的文件。'(001).        RETURN.    ENDCASE.  ENDMETHOD.

        7. 测试程序

          *&---------------------------------------------------------------------**& Report ZOBS_ATTCH_DOWNLOAD_TEST*&---------------------------------------------------------------------**&*&---------------------------------------------------------------------*REPORT zobs_demo_attch_display.SELECTION-SCREEN BEGIN OF BLOCK b1 WITH FRAME TITLE TEXT-s01.  PARAMETERS: p_bucket TYPE zzbucket_obs DEFAULT 'mrm-attachment'.  PARAMETERS: p_objkey TYPE zzobjectkey_obs .SELECTION-SCREEN END OF BLOCK b1.START-OF-SELECTION.  "显示对象  PERFORM frm_display_attachment.*&---------------------------------------------------------------------**& Form frm_display_attachment*&---------------------------------------------------------------------**& text*&---------------------------------------------------------------------**& -->  p1        text*& display_attachment    EXPORTING      iv_bucketname = p_bucket      iv_objectkey  = lv_objectkey      iv_dialog     = abap_false   "选择屏幕调用，参数设为空    IMPORTING      es_return     = ls_return.  IF ls_return IS NOT INITIAL..    MESSAGE ID ls_return-id          TYPE ls_return-type        NUMBER ls_return-number          WITH ls_return-message_v1               ls_return-message_v2               ls_return-message_v3               ls_return-message_v4.  ENDIF.ENDFORM.

          ​

      3.2.6 复制附件

      3.2.6.1 两步法：先下载再上载 COPY_ATTACHMENT_NEW

      ​ 由于华为云OBS API调用有问题，采用临时方案，先将文件下载，再将文件上载成另外一个对象**

      1. 先调用下载方法，获取文件的二进制；

      2. 将获取的二进制上载到新的对象Key；

      3. 源码实现

        **/*----------------------------------------------------------------------** 复制对象的结果不能仅根据HTTP返回头域中的status_code来判断请求是否成功，* 头域中status_code返回200时表示服务端已经收到请求，且开始处理复制对象请求。* 复制是否成功会在响应消息的body中，只有body体中有ETag标签才表示成功，* 否则表示复制失败。*----------------------------------------------------------------------**/METHOD copy_attachment_new.  DATA: lv_data       TYPE xstring,        lv_filelength TYPE i,        lv_message    TYPE bapi_msg.  "下载源文件  "下载附件  CALL METHOD download_object    EXPORTING      iv_bucketname  = iv_sourcebucket      iv_objectkey   = iv_sourceobject      iv_filetype    = 'BIN'      iv_direct_down = ''    IMPORTING      es_return      = es_return      es_result      = es_result.  IF es_return-type CA 'EAX'.    RETURN.  ENDIF.  lv_data = es_result-rawbizdata.  "上载目标文件  CALL METHOD upload_object    EXPORTING      iv_bucketname = iv_destbucket      iv_objectkey  = iv_destobject      iv_data       = lv_data    IMPORTING      es_return     = es_return      es_result     = es_result.  IF es_result-code = 200.    "附件上载成功，ObjectKey为&1.    MESSAGE s013 WITH iv_destobject INTO lv_message.    es_return = zcl_message=>convert_syst_to_bapiret2( ).  ELSE.    "附件上载失败，错误原因：&1&2    MESSAGE e014 WITH es_result-code es_result-reason INTO lv_message.    es_return = zcl_message=>convert_syst_to_bapiret2( ).  ENDIF.  "设置OBS操作  set_action( c_action_copy ).  "记录日志  logging_obslog( is_return = es_return is_result = es_result ).  "日志自动清理  clear_obslog( ).ENDMETHOD.
      3.2.6.2 一步法：直接调用OBS复制功能COPY_ATTACHMENT

      • 复制对象使用PUT方法;

      • 调用计算签名方法；

        计算签名的参数CanonicalizedHeaders中需要包含参数x-obs-copy-source。

        参数x-obs-copy-source

        用来指定复制对象操作的源桶名以及源对象名。当源对象存在多个版本时，通过versionId参数指定版本源对象。

        类型：String

        约束：中文字符，需要进行URLEncode

        示例：x-obs-copy-source: /source_bucket/sourceObject

      • 创建HTTP客户端，HOST需要包含Object Key；

      • 设置HTTP头域（Header）；

      • 发送请求，并提取返回的结果。

      3.2.6.3 测试程序
      *&---------------------------------------------------------------------**& Report ZOBS_ATTCH_DOWNLOAD_TEST*&---------------------------------------------------------------------**&*&---------------------------------------------------------------------*REPORT zobs_demo_attch_copy.SELECTION-SCREEN BEGIN OF BLOCK b1 WITH FRAME TITLE TEXT-s01.  PARAMETERS: p_srcbkt TYPE zzbucket_obs DEFAULT 'sap-mm-attachment '.  PARAMETERS: p_srcobj TYPE zzobjectkey_obs.  PARAMETERS: p_dstbkt TYPE zzbucket_obs DEFAULT 'sap-mm-attachment '.  PARAMETERS: p_dstobj TYPE zzobjectkey_obs.  SELECTION-SCREEN BEGIN OF BLOCK b2 WITH FRAME TITLE TEXT-s02.    PARAMETERS: p_copy1 RADIOBUTTON GROUP gp1.    PARAMETERS: p_copy2 RADIOBUTTON GROUP gp1 DEFAULT 'X'.  SELECTION-SCREEN END OF BLOCK b2.SELECTION-SCREEN END OF BLOCK b1.START-OF-SELECTION.  "复制对象  PERFORM frm_copy_attachment.*&---------------------------------------------------------------------**& Form frm_copy_attachment*&---------------------------------------------------------------------**& text*&---------------------------------------------------------------------**& -->  p1        text*& copy_attachment      EXPORTING        iv_sourcebucket = p_srcbkt        iv_sourceobject = lv_sourceobject        iv_destbucket   = p_dstbkt        iv_destobject   = lv_destobject      IMPORTING        es_return       = ls_return        es_result       = ls_result.  ELSE.    "先下载再上载    CALL METHOD lo_obs->copy_attachment_new      EXPORTING        iv_sourcebucket = p_srcbkt        iv_sourceobject = lv_sourceobject        iv_destbucket   = p_dstbkt        iv_destobject   = lv_destobject      IMPORTING        es_return       = ls_return        es_result       = ls_result.  ENDIF.  IF ls_return IS NOT INITIAL..    MESSAGE ID ls_return-id          TYPE 'S'        NUMBER ls_return-number          WITH ls_return-message_v1               ls_return-message_v2               ls_return-message_v3               ls_return-message_v4               DISPLAY LIKE ls_return-type.  ENDIF.ENDFORM.

      3.3 桶的基本操作

      3.3.1 列举桶内对象

      对桶拥有读权限的用户可以执行获取桶内对象列表的操作。

      如果用户在请求的URI里只指定了桶名，即GET /BucketName，则返回信息中会包含桶内部分或所有对象的描述信息（一次最多返回1000个对象信息）；如果用户还指定了prefix、marker、max-keys、delimiter参数中的一个或多个，则返回的对象列表将按照如表1所示规定的语义返回指定的对象。

      由于每次最多返回1000个文件，需要根据上次返回的NextMarker参数循环调用才能获取完整的对象列表。

      列举桶内对象的方法LIST_BUCKET_OBJECTS

      3.3.1.1 列举桶内对象采用GET方法
      3.3.1.2 计算签名

      访问桶内的对象清单是对桶的操作，所以请求访问的资源参数CanonicalizedResource指定为/BucketName/

      "获取OBS的签名CLEAR:ms_signtrue_req         ,      es_return               .ms_signtrue_req-bucketname             = iv_bucketname.ms_signtrue_req-httpmethod             = mv_http_method.ms_signtrue_req-authortype             = c_authortype_header.ms_signtrue_req-contenttype            = '' .ms_signtrue_req-contentmd5             = ''.ms_signtrue_req-canonicalizeheaders    = ''.ms_signtrue_req-canonicalizeresource   = '/'  && iv_bucketname && '/' .
      3.3.1.3 设置HTTP头域
      Date: dateAuthorization: authorization

      经过测试发现，Date一定要在Authorization，否则会报错，应该是OBS后端的设置导致的。

      3.3.1.4 设置url

      经测试发现，前缀prefix和起始标识marker只有拼接在URL中才生效。

      prefix：列举以指定的字符串prefix开头的对象

      marker：列举桶内对象列表时，指定一个标识符，从该标识符以后按字典顺序返回对象列表。等于上一次返回的NextMarker。

      NextMarker：如果本次没有返回全部结果，响应请求中将包含此字段，用于标明本次请求列举到的最后一个对象。后续请求可以指定Marker等于该值来列举剩余的对象。

      CLEAR: me->mt_parameters.  me->mt_parameters = VALUE #(   ( name = 'prefix'      value = iv_prefix      )   ( name = '&marker'     value = lv_nextmarker  )   ).
      3.3.1.5 调用HTTP返回对象清单
      3.3.1.6 解析返回的XML文件
        METHOD parse_list_bucket_result.    DATA: lr_ixml          TYPE REF TO if_ixml,          lr_streamfactory TYPE REF TO if_ixml_stream_factory,          lr_parser        TYPE REF TO if_ixml_parser,          lr_istram        TYPE REF TO if_ixml_istream,          lr_document      TYPE REF TO if_ixml_document.    "create main ixml factory    lr_ixml = cl_ixml=>create(  ).    "create a stream factory    lr_streamfactory = lr_ixml->create_stream_factory( ).    lr_istram = lr_streamfactory->create_istream_string( xmldata ).    "create a document    lr_document = lr_ixml->create_document( ).    "Creates a parser    lr_parser = lr_ixml->create_parser( document       = lr_document                                        istream        = lr_istram                                        stream_factory = lr_streamfactory                                       ).    IF lr_parser->parse( ) NE 0."Full parsing of input stream into a DOM.      IF lr_parser->num_errors( )  0."        RETURN.      ENDIF.    ENDIF.    IF lr_parser->is_dom_generating( ) = abap_true. "DOM是否生成      "解析DOM      is_truncated = parse_dom_document(        EXPORTING          document   = lr_document        IMPORTING          nextmarker = nextmarker ).    ENDIF.  ENDMETHOD.
        METHOD parse_dom_document.    DATA: lr_node     TYPE REF TO if_ixml_node,          lr_iterator TYPE REF TO if_ixml_node_iterator,          lr_node_map TYPE REF TO if_ixml_named_node_map,          lv_name     TYPE string,          lv_value    TYPE string.    lr_node " />mt_http_header = VALUE #( BASE  me->mt_http_header ( name = 'Date' vaule = ms_signtrue-date ) ). " 日期    me->mt_http_header = VALUE #( BASE  me->mt_http_header ( name = 'Authorization' vaule = ms_signtrue-authorization ) ). "CLEAR: me->mt_parameters.    me->mt_parameters = VALUE #(     ( name = 'prefix'      value = iv_prefix      )     ( name = '&marker'     value = lv_nextmarker  )     ).    "采用HTTP Client访问OBS    me->get_obs_object_list(      EXPORTING        iv_bucketname = iv_bucketname        it_parameters = me->mt_parameters      IMPORTING        es_return     = ls_return        es_result     = ls_result ).    IF ls_result-code = 200.      "获取桶&1对象列表成功.      MESSAGE s016 WITH iv_bucketname INTO lv_message.      es_return = zcl_message=>convert_syst_to_bapiret2( ).      "解析XML，获取文件列表      IF me->parse_list_bucket_result(        EXPORTING          xmldata = ls_result-bizdata        IMPORTING          nextmarker = lv_nextmarker )  me->c_true.        "如果解析出的XML文件中的IsTruncated=false时，标识已经返回全部结果，则终止循环        EXIT.      ENDIF.    ELSE.      "获取桶&1对象列表失败，错误原因：&1&2      MESSAGE e017 WITH ls_result-code  ls_result-reason INTO lv_message.      es_return = zcl_message=>convert_syst_to_bapiret2( ).      EXIT.    ENDIF.  ENDDO.  rt_object_list = me->mt_object_list. ENDMETHOD.
      3.3.1.8 测试程序
      *&---------------------------------------------------------------------**& Report ZOBS_DEMO_LIST_BUCKET_OBJECTS*&---------------------------------------------------------------------**&*&---------------------------------------------------------------------*REPORT zobs_demo_list_bucket_objects NO STANDARD PAGE HEADING MESSAGE-ID zobs.SELECTION-SCREEN BEGIN OF BLOCK b1 WITH FRAME TITLE TEXT-s01.  PARAMETERS: p_bucket TYPE zzbucket_obs DEFAULT 'sap-mm-attachment'.  PARAMETERS: p_prefix TYPE zzprefix_obs DEFAULT ''.SELECTION-SCREEN END OF BLOCK b1.START-OF-SELECTION.  PERFORM frm_get_object_list.*&---------------------------------------------------------------------**& Form frm_GET_OBJECT_LIST*&---------------------------------------------------------------------**& text*&---------------------------------------------------------------------**& -->  p1        text*& factory( ).  DATA(lt_object_list) = lr_obs->list_bucket_objects(    EXPORTING      iv_bucketname = p_bucket                 " OBS桶      iv_prefix     = p_prefix    IMPORTING      es_return     = ls_return               " 返回参数  ).    IF lt_object_list IS NOT INITIAL.    TRY.        cl_salv_table=>factory(          IMPORTING            r_salv_table = gr_table          CHANGING            t_table      = lt_object_list        ).        gr_salv = zcl_salv=>factory( ).        gr_salv->display(          EXPORTING            ir_table = gr_table          CHANGING            ct_data  = lt_object_list        ).      CATCH cx_salv_msg. " ALV: General Error Class with Message    ENDTRY.  ENDIF.ENDFORM.