org.pentaho.di.www

Class AllocateServerSocketServlet

java.lang.Object

javax.servlet.GenericServlet

javax.servlet.http.HttpServlet

org.pentaho.di.www.BaseHttpServlet

org.pentaho.di.www.AllocateServerSocketServlet

All Implemented Interfaces:

Serializable, javax.servlet.Servlet, javax.servlet.ServletConfig, CartePluginInterface, CarteServletInterface

public class AllocateServerSocketServlet
extends BaseHttpServlet
implements CartePluginInterface

This servlet allows a client (TransSplitter in our case) to ask for a port number.
This port number will be allocated in such a way that the port number is unique for a given hostname.
This in turn will ensure that all the slaves will use valid port numbers, even if multiple slaves run on the same host.

Author:

matt

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static String	CONTEXT_PATH
static String	PARAM_HOSTNAME
static String	PARAM_ID
static String	PARAM_RANGE_START
static String	PARAM_SOURCE_SLAVE
static String	PARAM_SOURCE_STEPCOPY
static String	PARAM_SOURCE_STEPNAME
static String	PARAM_TARGET_SLAVE
static String	PARAM_TARGET_STEPCOPY
static String	PARAM_TARGET_STEPNAME
static String	PARAM_TRANSFORMATION_NAME
static String	XML_TAG_PORT

Constructor Summary

Constructors

Constructor and Description
AllocateServerSocketServlet()
AllocateServerSocketServlet(TransformationMap transformationMap)

Method Summary

Modifier and Type	Method and Description
void	doGet(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response)
String	getContextPath()
String	getService()
String	toString()

Methods inherited from class org.pentaho.di.www.BaseHttpServlet

convertContextPath, getDetections, getJobMap, getSocketRepository, getTransformationMap, isJettyMode, logBasic, logBasic, logDebug, logDetailed, logDetailed, logError, logError, logError, logMinimal, logRowlevel, setJettyMode, setup

Methods inherited from class javax.servlet.http.HttpServlet

service

Methods inherited from class javax.servlet.GenericServlet

destroy, getInitParameter, getInitParameterNames, getServletConfig, getServletContext, getServletInfo, getServletName, init, init, log, log

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.pentaho.di.www.CartePluginInterface

isJettyMode, setJettyMode, setup

Field Detail

CONTEXT_PATH

public static final String CONTEXT_PATH

See Also:

Constant Field Values

PARAM_RANGE_START

public static final String PARAM_RANGE_START

See Also:

Constant Field Values

PARAM_HOSTNAME

public static final String PARAM_HOSTNAME

See Also:

Constant Field Values

PARAM_ID

public static final String PARAM_ID

See Also:

Constant Field Values

PARAM_TRANSFORMATION_NAME

public static final String PARAM_TRANSFORMATION_NAME

See Also:

Constant Field Values

PARAM_SOURCE_SLAVE

public static final String PARAM_SOURCE_SLAVE

See Also:

Constant Field Values

PARAM_SOURCE_STEPNAME

public static final String PARAM_SOURCE_STEPNAME

See Also:

Constant Field Values

PARAM_SOURCE_STEPCOPY

public static final String PARAM_SOURCE_STEPCOPY

See Also:

Constant Field Values

PARAM_TARGET_SLAVE

public static final String PARAM_TARGET_SLAVE

See Also:

Constant Field Values

PARAM_TARGET_STEPNAME

public static final String PARAM_TARGET_STEPNAME

See Also:

Constant Field Values

PARAM_TARGET_STEPCOPY

public static final String PARAM_TARGET_STEPCOPY

See Also:

Constant Field Values

XML_TAG_PORT

public static final String XML_TAG_PORT

See Also:

Constant Field Values

Constructor Detail

AllocateServerSocketServlet

public AllocateServerSocketServlet()

AllocateServerSocketServlet

public AllocateServerSocketServlet(TransformationMap transformationMap)

Method Detail

doGet

public void doGet(javax.servlet.http.HttpServletRequest request,
                  javax.servlet.http.HttpServletResponse response)
           throws javax.servlet.ServletException,
                  IOException

/kettle/allocateSocket

GET

Allocates port to use by client. Allows any client to ask for a port number to use. This is necessary several slaves can be run on the same host. The method ensures the port number is unique for host name provided and makes sure the slaves are using valid port numbers. Data communication across a cluster of Carte servers happens through TCP/IP sockets. Slave transformations sometimes open (or listen to) tens to hundreds of sockets. When you want to allocate the port numbers for data communication between slave transformation in a kettle clustering run, you need unique combinations of all the parameters below. port number will be returned in the Response object. If an error occurred you'll receive html output describing the problem. HTTP status code of such response is 500.

Example Request:

    GET /kettle/allocateSocket/?xml=Y&rangeStart=100&host=locahost&id=clust&trans=my_trans&sourceSlave=slave_1
  &sourceStep=200&sourceCopy=1&targetSlave=slave_2&targetStep=50&targetCopy=1
    

Parameters

name	description	type
xml	Boolean flag set to either Y or N describing if xml or html reply should be produced.	boolean, optional
rangeStart	Port number to start looking from.	integer
host	Port's host.	query
id	Carte container id.	query
trans	Running transformation id.	query
sourceSlave	Name of the source slave server.	query
sourceStep	Port number step used on source slave server.	integer
sourceCopy	Number of copies of the step on source server.	integer
targetSlave	Name of the target slave server.	query
targetStep	Port number step used on target slave server.	integer
targetCopy	Number of copies of the step on target server.	integer

Response Body

element:	(custom)
media types:	text/xml, text/html

Response wraps port number that was allocated or error stack trace if an error occurred. Response HTTP code is 200 if there were no errors. Otherwise it is 500.

Example Response:

    
    100
    

Status Codes

code	description
200	Request was processed and XML response is returned.
500	Internal server error occurs during request processing. This might also be caused by missing request parameter.

Specified by:

doGet in interface CartePluginInterface

Overrides:

doGet in class javax.servlet.http.HttpServlet

Throws:

javax.servlet.ServletException

IOException

toString

public String toString()

Overrides:

toString in class Object

getService

public String getService()

Specified by:

getService in interface CarteServletInterface

getContextPath

public String getContextPath()

Specified by:

getContextPath in interface CartePluginInterface