com.bigdata.rdf.sail.webapp

Class NanoSparqlServer

java.lang.Object

com.bigdata.rdf.sail.webapp.NanoSparqlServer

public class NanoSparqlServer
extends Object

Utility class provides a simple SPARQL end point with a REST API.

Author:

thompsonbry, martyncutcher

See Also:

NanoSparqlServer on the wiki., Jetty Documentation , Jetty XML Reference , Embedding Jetty

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	NanoSparqlServer.SystemProperties

Constructor Summary

Constructors

Constructor and Description
NanoSparqlServer()

Method Summary

Methods

Modifier and Type	Method and Description
static void	awaitServerStart(org.eclipse.jetty.server.Server server) Await a Server start up to a timeout.
protected static String	getHost() Utility method to get the host for the currently running NSS.
static int	getLocalPort(org.eclipse.jetty.server.Server server) Best effort attempt to return the port at which the local jetty Server is receiving http connections.
static org.eclipse.jetty.webapp.WebAppContext	getWebApp(org.eclipse.jetty.server.Server server) Return the WebAppContext for the Server.
static void	main(String[] args) Run an httpd service exposing a SPARQL endpoint.
static org.eclipse.jetty.server.Server	newInstance(int port, IIndexManager indexManager, Map<String,String> initParams) Start the embedded Server.
static org.eclipse.jetty.server.Server	newInstance(int port, String jettyXml, IIndexManager indexManager, Map<String,String> initParams) Start the embedded Server.
static org.eclipse.jetty.server.Server	newInstance(String jettyXml, IIndexManager indexManager, Map<String,String> initParams) Variant used when you already have the IIndexManager.
protected static void	usage(int status, String msg) Print the optional message on stderr, print the usage information on stderr, and then force the program to exit with the given status code.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

NanoSparqlServer

public NanoSparqlServer()

Method Detail

main

public static void main(String[] args)
                 throws Exception

Run an httpd service exposing a SPARQL endpoint. The service will respond to the following URL paths:

http://localhost:port/

The SPARQL end point for the default namespace as specified by the namespace command line argument.

http://localhost:port/namespace/NAMESPACE

where NAMESPACE is the namespace of some triple store or quad store, may be used to address ANY triple or quads store in the bigdata instance.

http://localhost:port/status

A status page.

Parameters:

args - USAGE:
To start the server:
(options) port namespace (propertyFile|configFile) )

Where:

port

The port on which the service will respond -or- 0 to use any open port.

namespace

The namespace of the default SPARQL endpoint (the namespace will be kb if none was specified when the triple/quad store was created).

propertyFile

A java properties file for a standalone Journal.

configFile

A jini configuration file for a bigdata federation.

and options are any of:

-jettyXml

The location of the jetty.xml resource that will be used to start the Server (default is the file in the JAR). The default will locate the jetty.xml resource that is bundled with the JAR. This preserves the historical behavior. If you want to use a different jetty.xml file, just override this property on the command line -or- specify the NanoSparqlServer.SystemProperties.JETTY_XML system property.

-nthreads

The #of threads which will be used to answer SPARQL queries (default ).

-forceOverflow

Force a compacting merge of all shards on all data services in a bigdata federation (this option should only be used for benchmarking purposes).

-readLock

The commit time against which the server will assert a read lock by holding open a read-only transaction against that commit point OR -1 (MINUS ONE) to assert a read lock against the last commit point. When given, queries will default to read against this commit point. Otherwise queries will default to read against the most recent commit point on the database. Regardless, each query will be issued against a read-only transaction.

-servletContextListenerClass

The name of a class that extends BigdataRDFServletContextListener. This allows you to hook the ServletContextListener events.

Throws:

Exception

awaitServerStart

public static void awaitServerStart(org.eclipse.jetty.server.Server server)
                             throws InterruptedException,
                                    TimeoutException,
                                    Exception

Await a Server start up to a timeout.

Throws:

InterruptedException

TimeoutException

Exception

getHost

protected static String getHost()
                         throws SocketException,
                                IOException

Utility method to get the host for the currently running NSS. If NicUtil returns a null pointer, it is set to the value of Config.DEFAULT_HOST.

Returns:

The hostname for the running instance.

Throws:

SocketException

IOException

newInstance

public static org.eclipse.jetty.server.Server newInstance(int port,
                                          IIndexManager indexManager,
                                          Map<String,String> initParams)
                                                   throws Exception

Start the embedded Server.

Note: The port override argument given here is applied by setting the NanoSparqlServer.SystemProperties.JETTY_PORT System property. The old value of that property is restored afterwards, but there is a side-effect which could be visible to concurrent threads.

Parameters:

port - The port on which the service will run -OR- ZERO (0) for any open port.

indexManager - The IIndexManager (optional).

initParams - Initialization parameters for the web application as specified by ConfigParams (optional).

Returns:

The server instance.

Throws:

Exception

See Also:

NanoSparqlServer.SystemProperties

newInstance

public static org.eclipse.jetty.server.Server newInstance(int port,
                                          String jettyXml,
                                          IIndexManager indexManager,
                                          Map<String,String> initParams)
                                                   throws Exception

Start the embedded Server.

Note: The port override argument given here is applied by setting the NanoSparqlServer.SystemProperties.JETTY_PORT System property. The old value of that property is restored afterwards, but there is a side-effect which could be visible to concurrent threads.

Parameters:

port - The port on which the service will run -OR- ZERO (0) for any open port.

jettyXml - The location of the jetty.xml resource.

indexManager - The IIndexManager (optional).

initParams - Initialization parameters for the web application as specified by ConfigParams (optional).

Returns:

The server instance.

Throws:

Exception

See Also:

NanoSparqlServer.SystemProperties

newInstance

public static org.eclipse.jetty.server.Server newInstance(String jettyXml,
                                          IIndexManager indexManager,
                                          Map<String,String> initParams)
                                                   throws Exception

Variant used when you already have the IIndexManager.

When the optional IIndexManager argument is specified, it will be set as an attribute on the WebAppContext. This will cause the webapp to use the pre-existing IIndexManager rather than attempting to open a new IIndexManager based on the propertyFile init parameter specified in web.xml. The HA initialization pattern relies on this.

When the IIndexManager is NOT specified, the life cycle of the IIndexManager will be managed by the server and the IndexManager instance will be opened (and eventually closed) by the BigdataRDFServletContextListener based on the configured value of the propertyFile init parameter in web.xml. This form is used by main(String[]) and can be used with either the Journal or the scale-out architecture.

Parameters:

jettyXml - The jetty.xml file that will be used to configure jetty.

indexManager - The IIndexManager (optional).

initParams - Optional map containing overrides for the init parameters declared in web.xml.

Returns:

The server instance.

Throws:

Exception

See Also:

Allow configuration of embedded NSS jetty server using jetty-web.xml

getWebApp

public static org.eclipse.jetty.webapp.WebAppContext getWebApp(org.eclipse.jetty.server.Server server)

Return the WebAppContext for the Server.

Parameters:

server - The Server.

Returns:

The WebAppContext associated with the bigdata webapp.

getLocalPort

public static int getLocalPort(org.eclipse.jetty.server.Server server)

Best effort attempt to return the port at which the local jetty Server is receiving http connections.

Parameters:

server - The server.

Returns:

The local port.

Throws:

IllegalArgumentException - if the argument is null.

usage

protected static void usage(int status,
         String msg)

Print the optional message on stderr, print the usage information on stderr, and then force the program to exit with the given status code.

Parameters:

status - The status code.

msg - The optional message