noradle-nodejs-client

introduce
==========

[noradle-nodejs-client][] use [noradle-protocol][] to connect to [noradle-dispatcher][],
access [oracle plsql servlet][noradle-oracle-server].

it support the following noradle modules:

* [noradle-http]
* [noradle-ndbc]
* [noradle-fcgi]

[noradle-nodejs-client]: https://github.com/noradle/noradle-nodejs-client
[noradle-protocol]: https://github.com/noradle/noradle-protocol
[noradle-dispatcher]: https://github.com/noradle/noradle-dispatcher
[noradle-http]: https://github.com/noradle/noradle-http
[noradle-ndbc]: https://github.com/noradle/noradle-ndbc
[noradle-fcgi]: https://github.com/noradle/noradle-fcgi
[noradle-oracle-server]: https://github.com/noradle/noradle-oracle-server

let client to connect to dispatcher
========================================

``
var DBDriver = require('noradle-nodejs-client').DBDriver;
var dbPool = DBDriver.connect([port, ip], {cid:"xxx", passwd:"xxx"});
`

* first parameter for DBDriver.connect is the same as node's socket.connect(),
id can be [port], [port,ip] or [path].
* secondary parameter for noradle.DBDriver.connect is client's client id and password for dispatcher

Use internal rudimentary API to access ORACLE
=============================================

it's like a node http request API with a db-driver like find free path to server beforehand.

`javascript

dbPool.findFree(env, db_selector, function(err, oraReq){
// env: identifier or marker for the request for logger or monitor
// db_selector: when dispatcher hold OSP from RAC/DG instances, specify the selection rule
// when dbPool find a free access slot, findFree callback will be called with a new oraReq instance
if (err) {
// basically, there are no error for dbPool.findFree
console.error(err);
return;
}
oraReq
.init('DATA', '')
.addHeader('uid', 'kaven276')
.addHeaders({dbu:'demo',prog:'show_user_name_b'}, 'x$')
.write(body)
.on('response', onResponse)
.on('error', onError)
.end(onResponse)
;
// .addHeader(s) can add name/value(s) pair that can be got by pl/sql r.getx series API
// .write(body) data will fill pl/sql package variable rb.blob_entity
// .end(onResponse) can is just .on('response', onRepsonse).end() combined
// any exception for the request/response cycle will emit error
// any pl/sql servlet call must have x$dbu,x$prog headers to specify which PL/SQL procedure to execute
function onResponse(oraRes) {
console.log(oraRes.status, oraRes.headers);
oraRes.on('data', function(data){
...
}
oraRes.on('end', function(){
...
}
}
function onError(error){
...
});
``