Use NDBC API to access ORACLE

through PL/SQL servlet can print arbitrary content to feed NDBC call, the most NDBC use is for fetch SQL result sets, so the example is for that.

The node javascript client who call in oracle plsql servlet

var DBDriver = require('noradle-nodejs-client')
  , NDBC = require('noradle-ndbc')
  , dbPool = DBDriver.connect([9009], {cid : 'test', passwd : 'test'})
  , dbc = new NDBC.DBCall(dbPool, {__parse : true, 'x$dbu': 'demo'})
  ;
dbc.call('db_src_b.example', {limit : 3}, function(status, headers, page){
  if(status!==200) {
    ...
    return;
  }
  console.log(status);
  console.log(headers);
  console.log(page);
});

Note:

• NDBC instance have dbPool as oracle access path supporting object as (dbPool, {...
• NDBC have default parameter in second parameter as {__parse : true, 'x$dbu': 'demo'}
• ndbc.call(stored_procedure_name, parameter, cb) will combine default parameter to make a PL/SQL servlet request
• callback(status, headers, page) is just like http response
• headers is name-value(s) pairs
• page is Buffer, String or Object type as headers['content-type'] indicate
• __parse : true will let noradle automatically convert certain response type to parsed javascript objects

for how raw SQL result is parsed, see noradle-resultsets

The oracle plsql sevlet code who generate SQL result sets

create or replace package body db_src_b is

    procedure example is
        cur sys_refcursor;
        v1  varchar2(50) := 'psp.web';
        v2  number := 123456;
        v3  date := date '1976-10-26';
    begin
        h.content_type('text/resultsets');

        open cur for
            select a.object_name, a.subobject_name, a.object_type, a.created
                from user_objects a
             where rownum <= r.getn('limit', 8);
        rs.print('test', cur);

        open cur for
            select v1 as name, v2 as val, v3 as ctime from dual;
        rs.print('namevals', cur);
    end;

end db_src_b;

Note:

• r.getn('limit', 8) will get number type parameter limit, as js code, it's 3, and default to 8 if no this input
• h.content_type('text/resultsets'); specify the response content-type is result sets that can be converted to javascript object or JSON text
• rs.print(name, sys_refcursor) will print SQL result and its meta data to condensed table format
• v1,v2,v3 is varchar2/number/date types, all scalar data can be printed out with from dual SQL

the data in transfer

[objects]�
OBJECT_NAME:1�,SUBOBJECT_NAME:1�,OBJECT_TYPE:1�,CREATED:12�
TOOL�,�,TYPE�,2015-04-20 16:38:39�
TOOL2�,�,TYPE�,2015-04-20 16:38:39�
TERM_T�,�,TABLE�,2015-04-20 16:38:45�
�
[namevals]�
NAME:1�,VAL:2�,CTIME:12�,P1:1�,P2:1�,PNULL:1�
psp.web�,123456�,1976-10-26 00:00:00�,value1�,value2�,�

Note:

• SQL resultsets is printed section by section
• one resultset have one meta line and zero, one or more data lines each line for one record
• columns/lines are separate not only with comma and linefeed, but with a hidden ACSII char together with separator so column content can safely have comma and linefeed.

the output

200
{ Date: 'Fri, 24 Jul 2015 00:55:46 GMT',
  'Content-Encoding': '?',
  'Content-Length': '649',
  'Content-Type': 'text/resultsets; charset=UTF-8',
  'x-pw-timespan': '40 / 40 ms' }
{ objects: 
   { name: 'objects',
     attrs: 
      [ { name: 'object_name', dataType: 1 },
        { name: 'subobject_name', dataType: 1 },
        { name: 'object_type', dataType: 1 },
        { name: 'created', dataType: 12 } ],
     rows: 
      [ { object_name: 'TOOL',
          subobject_name: '',
          object_type: 'TYPE',
          created: '2015-04-20 16:38:39' },
        { object_name: 'TOOL2',
          subobject_name: '',
          object_type: 'TYPE',
          created: '2015-04-20 16:38:39' },
        { object_name: 'TERM_T',
          subobject_name: '',
          object_type: 'TABLE',
          created: '2015-04-20 16:38:45' } ] },
  namevals: 
   { name: 'namevals',
     attrs: 
      [ { name: 'name', dataType: 1 },
        { name: 'val', dataType: 2 },
        { name: 'ctime', dataType: 12 },
        { name: 'p1', dataType: 1 },
        { name: 'p2', dataType: 1 },
        { name: 'pnull', dataType: 1 } ],
     rows: 
      [ { name: 'psp.web',
          val: 123456,
          ctime: '1976-10-26 00:00:00',
          p1: 'value1',
          p2: 'value2',
          pnull: '' } ] } }

Note:

• the parsed final result is javascript object, each key stand for one result set
• each result set have name, attrs(column meta data) array and rows array