simple-oracledb

simple-oracledb

Extend capabilities of oracledb with simplified API for quicker development.

• Overview
• Usage
  • OracleDB
    • createPool
  • Pool
    • getConnection
    • terminate
  • Connection
    • query
    • insert
    • update
    • queryJSON
    • batchInsert
    • release
    • rollback
• Installation
• Limitations
• API Documentation
• Release History
• License

Overview

This library enables to modify the oracledb main object, oracledb pool and oracledb connection of the official oracle node.js driver.
The main goal is to provide an extended oracledb connection which provides more functionality for most use cases.
The new functionality aim is to be simpler and more strait forward to enable quicker development.

Usage

In order to use this library, you need to either extend the main oracledb object as follows:

//load the oracledb library
var oracledb = require('oracledb');

//load the simple oracledb
var SimpleOracleDB = require('simple-oracledb');

//modify the original oracledb library
SimpleOracleDB.extend(oracledb);

//from this point connections fetched via oracledb.getConnection(...) or pool.getConnection(...)
//have access to additional functionality.
oracledb.getConnection(function onConnection(error, connection) {
    if (error) {
        //handle error
    } else {
        //work with new capabilities or original oracledb capabilities
        connection.query(...);
    }
}

Another option is to modify your oracledb pool instance (in case the pool was created outside your code and out of your control), as follows:

//load the simple oracledb
var SimpleOracleDB = require('simple-oracledb');

function myFunction(pool) {
    //modify the original oracledb pool instance
    SimpleOracleDB.extend(pool);

    //from this point connections fetched via pool.getConnection(...)
    //have access to additional functionality.
    pool.getConnection(function onConnection(error, connection) {
        if (error) {
            //handle error
        } else {
            //work with new capabilities or original oracledb capabilities
            connection.query(...);
        }
    }
}

One last option is to modify your oracledb connection instance (in case the connection was created outside your code and out of your control), as follows:

//load the simple oracledb
var SimpleOracleDB = require('simple-oracledb');

function doSomething(connection, callback) {
    //modify the original oracledb connection instance
    SimpleOracleDB.extend(connection);

    //from this point the connection has access to additional functionality as well as the original oracledb capabilities.
    connection.query(...);
}

'oracledb.createPool(poolAttributes, callback)'

This function modifies the existing oracledb.createPool function by enhancing the returned pool to support retry in the getConnection function.
The pool.getConnection will retry configurable amount of times with configurable interval between attempts to return a connection in the getConnection function.
In case all attempts fail, the getConnection callback will receive the error object of the last attempt.

oracledb.createPool({
  retryCount: 5, //The max amount of retries to get a connection from the pool in case of any error (default to 10 if not provided)
  retryInterval: 500, //The interval in millies between get connection retry attempts (defaults to 250 millies if not provided)
  runValidationSQL: true, //True to ensure the connection returned is valid by running a test validation SQL (defaults to true)
  validationSQL: 'SELECT 1 FROM DUAL', //The test SQL to invoke before returning a connection to validate the connection is open (defaults to 'SELECT 1 FROM DUAL')
  //any other oracledb pool attributes
}, function onPoolCreated(error, pool) {
  //continue flow
});

'pool.getConnection(callback)'

This function will attempt to fetch a connection from the pool and in case of any error will reattempt for a configurable amount of times.
It will also ensure the provided connection is valid by running a test SQL and if validation fails, it will fetch another connection (continue to reattempt).
See https://github.com/oracle/node-oracledb/blob/master/doc/api.md#getconnectionpool for official API details.
See https://github.com/sagiegurari/simple-oracledb/blob/master/docs/api.md#SimpleOracleDB.oracle.createPool for extended createPool API details.

oracledb.createPool({
  retryCount: 5, //The max amount of retries to get a connection from the pool in case of any error (default to 10 if not provided)
  retryInterval: 500, //The interval in millies between get connection retry attempts (defaults to 250 millies if not provided)
  runValidationSQL: true, //True to ensure the connection returned is valid by running a test validation SQL (defaults to true)
  validationSQL: 'SELECT 1 FROM DUAL', //The test SQL to invoke before returning a connection to validate the connection is open (defaults to 'SELECT 1 FROM DUAL')
  //any other oracledb pool attributes
}, function onPoolCreated(error, pool) {
  pool.getConnection(function onConnection(poolError, connection) {
    //continue flow (connection, if provided, has been tested to ensure it is valid)
  });
});

'pool.terminate([callback])'

This function modifies the existing pool.terminate function by enabling the input callback to be an optional parameter.
Since there is no real way to release the pool that fails to be terminated, all that you can do in the callback is just log the error and continue.
Therefore this function allows you to ignore the need to pass a callback and makes it as an optional parameter.

pool.terminate(); //no callback needed

//still possible to call with a terminate callback function
pool.terminate(function onTerminate(error) {
  if (error) {
    //now what?
  }
});

'connection.query(sql, bindVariables, [options], callback)'

Provides simpler interface than the original oracledb connection.execute function to enable simple query invocation.
The callback output will be an array of objects, each object holding a property for each field with the actual value.
All LOBs will be read and all rows will be fetched.
This function is not recommended for huge results sets or huge LOB values as it will consume a lot of memory.
The function arguments used to execute the 'query' are exactly as defined in the oracledb connection.execute function.

connection.query('SELECT department_id, department_name FROM departments WHERE manager_id < :id', [110], function onResults(error, results) {
  if (error) {
    //handle error...
  } else {
    //print the 4th row DEPARTMENT_ID column value
    console.log(results[3].DEPARTMENT_ID);
  }
});

'connection.insert(sql, bindVariables, options, callback)'

Provides simpler interface than the original oracledb connection.execute function to enable simple insert invocation with LOB support.
The callback output will be the same as oracledb conection.execute.
All LOBs will be written to the DB via streams and only after all LOBs are written the callback will be called.
The function arguments used to execute the 'insert' are exactly as defined in the oracledb connection.execute function, however the options are mandatory.

connection.insert('INSERT INTO mylobs (id, clob_column1, blob_column2) VALUES (:id, EMPTY_CLOB(), EMPTY_BLOB())', { //no need to specify the RETURNING clause in the SQL
  id: 110,
  clobText1: 'some long clob string', //add bind variable with LOB column name and text content (need to map that name in the options)
  blobBuffer2: new Buffer('some blob content, can be binary...')  //add bind variable with LOB column name and text content (need to map that name in the options)
}, {
  autoCommit: true, //must be set to true in options to support auto commit after update is done, otherwise the auto commit will be false (oracledb.autoCommit is not checked)
  lobMetaInfo: { //if LOBs are provided, this data structure must be provided in the options object and the bind variables parameter must be an object (not array)
    clob_column1: 'clobText1', //map oracle column name to bind variable name
    blob_column2: 'blobBuffer2'
  }
}, function onResults(error, output) {
  //continue flow...
});

'connection.update(sql, bindVariables, options, callback)'

Provides simpler interface than the original oracledb connection.execute function to enable simple update invocation with LOB support.
The callback output will be the same as oracledb conection.execute.
All LOBs will be written to the DB via streams and only after all LOBs are written the callback will be called.
The function arguments used to execute the 'update' are exactly as defined in the oracledb connection.execute function, however the options are mandatory.

connection.update('UPDATE mylobs SET name = :name, clob_column1 = EMPTY_CLOB(), blob_column2 = EMPTY_BLOB() WHERE id = :id', { //no need to specify the RETURNING clause in the SQL
  id: 110,
  name: 'My Name',
  clobText1: 'some long clob string', //add bind variable with LOB column name and text content (need to map that name in the options)
  blobBuffer2: new Buffer('some blob content, can be binary...')  //add bind variable with LOB column name and text content (need to map that name in the options)
}, {
  autoCommit: true, //must be set to true in options to support auto commit after update is done, otherwise the auto commit will be false (oracledb.autoCommit is not checked)
  lobMetaInfo: { //if LOBs are provided, this data structure must be provided in the options object and the bind variables parameter must be an object (not array)
    clob_column1: 'clobText1', //map oracle column name to bind variable name
    blob_column2: 'blobBuffer2'
  }
}, function onResults(error, output) {
  //continue flow...
});

'connection.queryJSON(sql, [bindVariables], [options], callback)'

This function will invoke the provided SQL SELECT and return a results object with the returned row count and the JSONs.
The json property will hold a single JSON object in case the returned row count is 1, and an array of JSONs in case the row count is higher.
The query expects that only 1 column is fetched and if more are detected in the results, this function will return an error in the callback.
The function arguments used to execute the 'queryJSON' are exactly as defined in the oracledb connection.execute function.

connection.queryJSON('SELECT JSON_DATA FROM APP_CONFIG WHERE ID > :id', [110], function onResults(error, results) {
  if (error) {
    //handle error...
  } else if (results.rowCount === 1) { //single JSON is returned
    //print the JSON
    console.log(results.json);
  } else if (results.rowCount > 1) { //multiple JSONs are returned
    //print the JSON
    results.json.forEach(function printJSON(json) {
      console.log(json);
    });
  } else {
    console.log('Did not find any results');
  }
});

'connection.batchInsert(sql, bindVariablesArray, options, callback)'

Enables to run an INSERT SQL statement multiple times for each of the provided bind params.
This allows to insert to same table multiple different rows with one single call.
The callback output will be an array of objects of same as oracledb conection.execute (per row).
All LOBs for all rows will be written to the DB via streams and only after all LOBs are written the callback will be called.
The function arguments used to execute the 'insert' are exactly as defined in the oracledb connection.execute function, however the options are mandatory and the bind params is now an array of bind params (one per row).

connection.batchInsert('INSERT INTO mylobs (id, clob_column1, blob_column2) VALUES (:id, EMPTY_CLOB(), EMPTY_BLOB())', [ //no need to specify the RETURNING clause in the SQL
  { //first row values
    id: 110,
    clobText1: 'some long clob string', //add bind variable with LOB column name and text content (need to map that name in the options)
    blobBuffer2: new Buffer('some blob content, can be binary...')  //add bind variable with LOB column name and text content (need to map that name in the options)
  },
  { //second row values
    id: 111,
    clobText1: 'second row',
    blobBuffer2: new Buffer('second rows')
  }
], {
  autoCommit: true, //must be set to true in options to support auto commit after insert is done, otherwise the auto commit will be false (oracledb.autoCommit is not checked)
  lobMetaInfo: { //if LOBs are provided, this data structure must be provided in the options object and the bind variables parameter must be an object (not array)
    clob_column1: 'clobText1', //map oracle column name to bind variable name
    blob_column2: 'blobBuffer2'
  }
}, function onResults(error, output) {
  //continue flow...
});

'connection.release([callback])'

This function modifies the existing connection.release function by enabling the input callback to be an optional parameter.
Since there is no real way to release a connection that fails to be released, all that you can do in the callback is just log the error and continue.
Therefore this function allows you to ignore the need to pass a callback and makes it as an optional parameter.

connection.release(); //no callback needed

//still possible to call with a release callback function
connection.release(function onRelease(error) {
  if (error) {
    //now what?
  }
});

'connection.rollback([callback])'

This function modifies the existing connection.rollback function by enabling the input callback to be an optional parameter.
If rollback fails, you can't really rollback again the data, so the callback is not always needed.
Therefore this function allows you to ignore the need to pass a callback and makes it as an optional parameter.

connection.rollback(); //no callback needed

//still possible to call with a rollback callback function
connection.rollback(function onRollback(error) {
  if (error) {
    //now what?
  }
});

**The rest of the API is the same as defined in the oracledb library: https://github.com/oracle/node-oracledb/blob/master/doc/api.md**

Installation

In order to use this library, just run the following npm install command:

npm install --save simple-oracledb

This library doesn't define oracledb as a dependency and therefore it is not installed when installing simple-oracledb.
You should define oracledb in your package.json and install it based on the oracledb installation instructions found at: https://github.com/oracle/node-oracledb/blob/master/INSTALL.md

Limitations

The simpler API can lead to higher memory consumption and therefore might not be suitable in all cases.

Also, since this is work in progress, only few capabilities currently were added.
However, in the near future more and more functionality will be added.

API Documentation

See full docs at: API Docs

Release History

Date	Version	Description
2015-12-12	v0.0.28	Maintenance
2015-12-08	v0.0.24	Added pool.getConnection connection validation via running SQL test command
2015-11-30	v0.0.23	Maintenance
2015-11-17	v0.0.17	Added pool.getConnection automatic retry
2015-11-15	v0.0.16	Added connection.batchInsert and connection.rollback
2015-11-05	v0.0.15	Maintenance
2015-10-20	v0.0.10	Added connection.queryJSON
2015-10-19	v0.0.9	autoCommit support when doing INSERT/UPDATE with LOBs
2015-10-19	v0.0.7	Added pool.terminate
2015-10-19	v0.0.6	Maintenance
2015-10-18	v0.0.5	Added connection.update
2015-10-18	v0.0.4	Added connection.insert
2015-10-16	v0.0.3	Maintenance
2015-10-15	v0.0.1	Initial release.

License

Developed by Sagie Gur-Ari and licensed under the Apache 2 open source license.