EBS开发附件上传和下载功能

上传

Oracle ERP二次开发中使用的方式有两种，一是通过标准功能，在系统管理员中定义即可，不用写代码，就可以使几乎任何Form具有附件功能，具体参考系统管理员文档；二是通过PL/SQL Gateway，需要我们便写代码完成。该方式其实和上述方式一的后台实现是一样的

程序说明

1、Package功能，测试通过PL/SQLGateway（MOD PL/SQL）完成文件上传下载  
  2、本Package直接使用EBS的DAD，所以对应的Document表为APPS.fnd_lobs_document
    在非EBS环境开发，需要自己定义DAD请参考9ias_plsql.pdf和9ias.pdf，步骤如下
    a、创建Document表，参照fnd_lobs_document和fnd_lobs_documentpart，表名自己起
    b、配置DAD，配置文件为$IAS_ORACLE_HOME/Apache/modplsql/cfg/wdbsvr.app
    c、参照fnd_gfm，改写成自己的包，或者简单点改写本Package也行
  3、需要把我们写的包在system administrator--> security --> Web PL/SQL里面注册一下，
    不然通过IE打开会提示用户名和密码
  4、本测试把在“接口”fnd_lobs_document中的附件，按照EBS的做法保存到fnd_lobs，
    也可以改写代码保存到自己的表，一般没必要，我们自己的表保存File_ID即可
  5、一个表中的BLOB等数据可以直接插入另一个表

下载

上传的文件时存到了fnd_lobs表中以BLOB数据的形式存储，现在要把BLOB数据以原文件的格式读取出来，并且给最终用户提供下载该文件的功能

方法如下

declare
v_file_id NUMBER;
url VARCHAR2(500);
begin 
--Get the file_id of the file which you want to download in fnd_lobs 
v_file_id := xxxxxx;
--Get The Download URL
url := fnd_gfm.construct_download_url(fnd_web_config.gfm_agent,v_file_id,TRUE);
fnd_utilities.open_url(url);
end;

以上的方法就可以轻松的实现下载存储在fnd_lobs中的文件，只要告诉fnd_gfm.construct_download_url在fnd_lobs表中文件的file_id，就可以轻松取得URL，使用fnd_utilities.open_url就可以下载该文件；不过现在还有一个问题就是要在工作流发送的消息找到一个东西（比如说一个按钮、超链接）来执行下载文件的方法可以在document类型的ATTRIBUTE里设置一个超链接，然后让这个超链接的地址指向我已经取得的下载文件的URL

CREATE OR REPLACE PACKAGE oracle_up_down AUTHID CURRENT_USER IS
  /********************************************
  1、Package功能，测试通过PL/SQL Gateway（MOD PL/SQL）完成文件上传下载  
  2、本Package直接使用EBS的DAD，所以对应的Document表为APPS.fnd_lobs_document
    在非EBS环境开发，需要自己定义DAD请参考9ias_plsql.pdf和9ias.pdf，步骤如下
    1、创建Document表，参照fnd_lobs_document和fnd_lobs_documentpart，表名自己起
    2、配置DAD，配置文件为$IAS_ORACLE_HOME/Apache/modplsql/cfg/wdbsvr.app
    3、参照fnd_gfm，改写成自己的包，或者简单点改写本Package也行
  3、需要把我们写的包在system administrator --> security --> Web PL/SQL里面注册一下，
    不然通过IE打开会提示用户名和密码
  4、本测试把在“接口”fnd_lobs_document中的附件，按照EBS的做法保存到fnd_lobs，
    也可以改写代码保存到自己的表，一般没必要，我们自己的表保存File_ID即可
  5、一个表中的BLOB等数据可以直接插入另一个表
  
  ********************************************/
  /***************上传文件下载过程*************
  1、初始化access id
  select fnd_gfm.authorize(-1) from dual;
  
  2、准备url，下面是例子
  SELECT fnd_web_config.trail_slash(fnd_profile.VALUE('APPS_WEB_AGENT')) ||
       'oracle_up_down.upload_form?p_access_id=上面1的查询结果'
  FROM dual;
  
  3、用浏览器打开url即可。如果是通过Form打开url上传，那么把上面代码放入form的相应trigger
  
  4、查看File_ID
  SELECT fnd_web_config.trail_slash(fnd_profile.VALUE('APPS_WEB_AGENT')) ||
       'oracle_up_down.upload_form?p_access_id=上面1的查询结果'
  FROM dual;
  
  4、把文件下载下来验证
  SELECT fnd_web_config.trail_slash(fnd_profile.VALUE('APPS_WEB_AGENT')) ||
       'oracle_up_down.download_file?p_file_id=上面4的查询结果' || chr(38) ||
       'p_access_id=上面1的查询结果'
  FROM dual;
  
  5、可以直接在PL/SQL Developer 6以上中Select出来点击File_Data察看
  
  Test脚本
  http://hw321.huawei.com:8003/pls/scp/fnd_web.SHOWENV;
  select fnd_gfm.authorize(-1) from dual;
  select * from applsys.fnd_lob_access t where t.access_id = 354896931892;
  http://hw321.huawei.com:8003/pls/SCP/oracle_up_down.upload_form?p_access_id=354896931892;
  select * from applsys.fnd_lob_access t where t.access_id = 354896931892;
  select * from applsys.fnd_lobs_document t;
  http://hw321.huawei.com:8003/pls/SCP/oracle_up_down.download_file?p_file_id=3548970&p_access_id=354896931892;
  Select * from fnd_lobs flb where flb.file_id = 3548970;
  ****************上传文件下载过程*****************/

  g_agent        CONSTANT VARCHAR2(100) := fnd_web_config.trail_slash(fnd_profile.VALUE('APPS_WEB_AGENT'));
  g_package_name CONSTANT VARCHAR2(100) := 'oracle_up_down';
  g_upload_url   CONSTANT VARCHAR2(100) := g_package_name || '.upload_file';
  g_download_url CONSTANT VARCHAR2(100) := g_package_name ||
                                           '.download_file';
  g_cancel_url   CONSTANT VARCHAR2(100) := g_package_name || '.cancel_file';

  --完成上传：把在网关中的数据抓到自己的表
  PROCEDURE upload_file(p_file_name IN VARCHAR2, p_access_id IN NUMBER);
  --显示HTML取消页面
  PROCEDURE upload_cancel;
  --显示HTML上传页面
  PROCEDURE upload_form(p_access_id IN NUMBER DEFAULT NULL);
  --下载文件
  PROCEDURE download_file(p_file_id   IN NUMBER,
                          p_access_id IN NUMBER,
                          p_purge     IN VARCHAR2 DEFAULT NULL);

  PROCEDURE download_file_html(p_file_id   IN NUMBER,
                               p_access_id IN NUMBER,
                               p_purge     IN VARCHAR2 DEFAULT NULL);

END;
/
CREATE OR REPLACE PACKAGE BODY oracle_up_down IS

  --add '/' to a string
  FUNCTION trail_slash(p_val IN VARCHAR2) RETURN VARCHAR2 IS
    l_copy_val VARCHAR2(2000);
  BEGIN
    l_copy_val := p_val;
    WHILE (substr(l_copy_val, -1, 1) = '/') LOOP
      l_copy_val := substr(l_copy_val, 1, length(l_copy_val) - 1);
    END LOOP;
    RETURN l_copy_val || '/';
  END;

  PROCEDURE err_msg(NAME VARCHAR2) IS
  BEGIN
    fnd_message.set_name('FND', 'SQL_PLSQL_ERROR');
    fnd_message.set_token('ROUTINE', 'FND_GFM.' || NAME);
    fnd_message.set_token('ERRNO', SQLCODE);
    fnd_message.set_token('REASON', SQLERRM);
  END err_msg;

  /*
  从fnd_gfm拷贝过来，原来的代码是删除整个fnd_lobs_document，不知道为何，现在改为仅删除上传的文件
  */

  FUNCTION confirm_upload(access_id       NUMBER,
                          file_name       VARCHAR2,
                          program_name    VARCHAR2 DEFAULT NULL,
                          program_tag     VARCHAR2 DEFAULT NULL,
                          expiration_date DATE DEFAULT NULL,
                          LANGUAGE        VARCHAR2 DEFAULT userenv('LANG'),
                          wakeup          BOOLEAN DEFAULT FALSE)
    RETURN NUMBER IS
    fid        NUMBER := -1;
    fn         VARCHAR2(256);
    mt         VARCHAR2(240);
    bloblength NUMBER; -- bug 3045375, added variable to set length of blob.
  BEGIN
    IF (fnd_gfm.authenticate(confirm_upload.access_id)) THEN
      SELECT fnd_lobs_s.NEXTVAL INTO fid FROM dual;
    
      fn := substr(confirm_upload.file_name,
                   instr(confirm_upload.file_name, '/') + 1);
    
      -- bug 3045375, added select to get length of BLOB.
      SELECT dbms_lob.getlength(blob_content), mime_type
        INTO bloblength, mt
        FROM fnd_lobs_document
       WHERE NAME = confirm_upload.file_name
         AND rownum = 1;
    
      -- bug 3045375, added if to check length of blob.
      IF bloblength > 0 THEN
        INSERT INTO fnd_lobs
          (file_id,
           file_name,
           file_content_type,
           file_data,
           upload_date,
           expiration_date,
           program_name,
           program_tag,
           LANGUAGE,
           file_format)
          (SELECT confirm_upload.fid,
                  fn,
                  ld.mime_type,
                  ld.blob_content,
                  SYSDATE,
                  confirm_upload.expiration_date,
                  confirm_upload.program_name,
                  confirm_upload.program_tag,
                  confirm_upload.LANGUAGE,
                  fnd_gfm.set_file_format(mt)
             FROM fnd_lobs_document ld
            WHERE ld.NAME = confirm_upload.file_name
              AND rownum = 1);
      
        IF (SQL%ROWCOUNT <> 1) THEN
          RAISE no_data_found;
        END IF;
      
        UPDATE fnd_lob_access
           SET file_id = fid
         WHERE access_id = confirm_upload.access_id;
      
        IF wakeup THEN
          dbms_alert.signal('FND_GFM_ALERT' || to_char(access_id),
                            to_char(fid));
        END IF;
        -- bug 3045375, added else to return fid = -2.
      ELSE
        fid := -2;
      END IF;
      DELETE FROM fnd_lobs_document ld
       WHERE ld.NAME = confirm_upload.file_name;
      --delete from fnd_lobs_documentpart;
    END IF;
    RETURN fid;
  EXCEPTION
    WHEN OTHERS THEN
      DELETE FROM fnd_lobs_document ld
       WHERE ld.NAME = confirm_upload.file_name;
      --delete from fnd_lobs_documentpart;
    
      err_msg('confirm_upload');
      RAISE;
  END;

  PROCEDURE upload_file(p_file_name IN VARCHAR2, p_access_id IN NUMBER) IS
    l_file_id NUMBER;
  BEGIN
  
    l_file_id := confirm_upload(access_id    => p_access_id,
                                file_name    => p_file_name,
                                program_name => g_package_name);
  
    IF l_file_id NOT IN (-1, -2) THEN
      -- File upload completed
      htp.htmlopen;
      htp.headopen;
      htp.title('文件上传');
      htp.headclose;
      htp.bodyopen;
      htp.img2('/images/wwcban.jpg', calign => 'Center', calt => 'Logo');
      htp.br;
      htp.br;
      htp.p('<h4>' || '文件上传' || '</h4>');
      htp.hr;
      htp.p(htf.bold('文件上传完成。Select * from fnd_lobs flb where flb.file_id = ' ||
                     l_file_id));
      htp.br;
    
      htp.p('<h4>' || '请关闭浏览器！' || '</h4>');
      htp.br;
      htp.bodyclose;
      htp.htmlclose;
    
    ELSE
      -- File upload failed.
      htp.htmlopen;
      htp.headopen;
      htp.title('文件上传');
      htp.headclose;
      htp.bodyopen;
      htp.img2('/images/wwcban.jpg', calign => 'Left', calt => 'Logo');
      htp.br;
    
      htp.hr;
      htp.p(htf.bold('文件上传失败！'));
      htp.br;
      htp.bodyclose;
      htp.htmlclose;
    END IF;
  
  END;

  PROCEDURE upload_cancel AS
  
  BEGIN
  
    -- Show a message page
    htp.htmlopen;
    htp.headopen;
    htp.title('取消文件上传');
    htp.headclose;
    htp.bodyopen;
    htp.img2('/images/wwcban.jpg', calign => 'Center', calt => 'Logo');
    htp.br;
    htp.br;
    htp.p('<h4>' || '文件上传' || '</h4>');
    htp.hr;
    htp.p(htf.bold('取消文件上传'));
    htp.br;
    htp.p('<h4>' || '您已经选择取消文件上传。' || '</h4>');
    htp.p('<h4>' || '请关闭浏览器！' || '</h4>');
    htp.br;
    htp.br;
    htp.br;
    htp.bodyclose;
    htp.htmlclose;
  
  END;

  PROCEDURE upload_form(p_access_id IN NUMBER DEFAULT NULL) IS
    l_upload_action VARCHAR2(2000);
  BEGIN
  
    -- Set the upload action  
    l_upload_action := fnd_gfm.construct_upload_url(g_agent,
                                                    g_upload_url,
                                                    p_access_id);
    -- Set page title and toolbar.
    htp.htmlopen;
    htp.headopen;
    htp.p('<SCRIPT LANGUAGE="JavaScript">');
    htp.p(' function processclick (cancel_url) {
                 if (confirm(' || '"' || '取消文件上传' || '"' || '))
                 {
                        parent.location=cancel_url
                 }
              }');
    htp.print('</SCRIPT>');
    htp.title('文件上传');
    htp.headclose;
    htp.bodyopen;
    htp.img2('/images/wwcban.jpg', calign => 'Center', calt => 'Logo');
    htp.br;
    htp.br;
    htp.p('<h4>' || '文件上传' || '</h4>');
    htp.hr;
    htp.br;
    htp.print('</LEFT>');
  
    htp.formopen(curl     => l_upload_action,
                 cmethod  => 'POST',
                 cenctype => 'multipart/form-data');
    htp.tableopen(cattributes => ' border=0 cellpadding=2 cellspacing=0');
    htp.tablerowopen;
    htp.tablerowclose;
  
    htp.tablerowopen(cvalign => 'TOP');
    htp.p('<TD>');
    htp.p('</TD>');
    htp.p('<label>文件</label>');
    htp.tabledata('<INPUT TYPE="File" NAME="p_file_name" SIZE="60">',
                  calign => 'left');
    htp.tablerowclose;
    htp.tableclose;
  
    -- Send access is as a hidden value
    htp.formhidden(cname => 'p_access_id', cvalue => to_char(p_access_id));
  
    htp.br;
    htp.tableopen(cattributes => ' border=0 cellpadding=2 cellspacing=0');
    htp.tablerowopen(cvalign => 'TOP');
    htp.tabledata('<INPUT TYPE="Submit" VALUE="' || '确定' ||
                  '" SIZE="50">',
                  calign => 'left');
    htp.tabledata('<INPUT TYPE="Button" NAME="cancel" VALUE="' || '取消' || '"' ||
                  ' onClick="processclick(''' || g_cancel_url ||
                  ''') " SIZE="50">',
                  calign => 'left');
    htp.tablerowclose;
    htp.tableclose;
    htp.formclose;
  
    htp.bodyclose;
    htp.htmlclose;
  END;

  PROCEDURE download_file(p_file_id   IN NUMBER,
                          p_access_id IN NUMBER,
                          p_purge     IN VARCHAR2 DEFAULT NULL) IS
  BEGIN
    fnd_gfm.download(p_file_id, p_access_id, p_purge);
  END;

  PROCEDURE download_file_html(p_file_id   IN NUMBER,
                               p_access_id IN NUMBER,
                               p_purge     IN VARCHAR2 DEFAULT NULL) IS
  BEGIN
    htp.print('
    <html>
    <body>
      <img src=' || g_download_url || '?p_file_id=' ||
              p_file_id || chr(38) || 'p_access_id=' || p_access_id ||
              ' border=0>
    </body>
    </html>
    ');
  END;
END;
/