org.apache.tinkerpop.gremlin.server.op.session

Class SessionOpProcessor

java.lang.Object

org.apache.tinkerpop.gremlin.server.op.AbstractOpProcessor

org.apache.tinkerpop.gremlin.server.op.AbstractEvalOpProcessor

org.apache.tinkerpop.gremlin.server.op.session.SessionOpProcessor

All Implemented Interfaces:

AutoCloseable, OpProcessor

public class SessionOpProcessor
extends AbstractEvalOpProcessor

Simple OpProcessor implementation that handles ScriptEngine script evaluation in the context of a session. Note that this processor will also take a "close" op to kill the session and rollback any incomplete transactions.

Author:

Stephen Mallette (http://stephen.genoprime.com)

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.tinkerpop.gremlin.server.op.AbstractEvalOpProcessor

AbstractEvalOpProcessor.BindingSupplier

Field Summary

Fields

Modifier and Type	Field and Description
static String	CONFIG_GLOBAL_FUNCTION_CACHE_ENABLED Configuration setting that behaves as an override to the global script engine setting of the same name that is provided to the GroovyCompilerGremlinPlugin.
static String	CONFIG_PER_GRAPH_CLOSE_TIMEOUT Configuration setting for how long to wait in milliseconds for each configured graph to close any open transactions when the session is killed.
static String	CONFIG_SESSION_TIMEOUT Configuration setting for how long a session will be available before it times out.
static long	DEFAULT_PER_GRAPH_CLOSE_TIMEOUT Default amount of time to wait in milliseconds for each configured graph to close any open transactions when the session is killed.
static long	DEFAULT_SESSION_TIMEOUT Default timeout for a session is eight hours.
static String	OP_PROCESSOR_NAME
protected static ConcurrentHashMap<String,Session>	sessions Script engines are evaluated in a per session context where imports/scripts are isolated per session.

Fields inherited from class org.apache.tinkerpop.gremlin.server.op.AbstractEvalOpProcessor

CONFIG_MAX_PARAMETERS, DEFAULT_MAX_PARAMETERS, evalOpTimer, INVALID_BINDINGS_KEYS, maxParameters

Fields inherited from class org.apache.tinkerpop.gremlin.server.op.AbstractOpProcessor

manageTransactions

Constructor Summary

Constructors

Constructor and Description
SessionOpProcessor()

Method Summary

Modifier and Type	Method and Description
protected void	beforeProcessing(Graph graph, Context ctx)
void	close()
protected void	evalOp(Context context)
protected Function<Context,AbstractEvalOpProcessor.BindingSupplier>	getBindingMaker(Session session) A useful method for those extending this class, where the means for binding construction can be supplied to this class.
ThrowingConsumer<Context>	getEvalOp() Provides an operation for evaluating a Gremlin script.
String	getName() The name of the processor which requests must refer to "processor" field on a request.
protected static Session	getSession(Context context, RequestMessage msg) Examines the RequestMessage and extracts the session token.
protected void	handleGraphOperation(Bytecode bytecode, Graph graph, Context context) If Bytecode is detected to contain a "graph operation" then it gets processed by this method.
protected void	handleIterator(Context context, Iterator itty, Graph graph)
void	init(Settings settings) Initialize the OpProcessor with settings from the server.
protected void	onError(Graph graph, Context ctx)
protected void	onTraversalSuccess(Graph graph, Context ctx)
Optional<ThrowingConsumer<Context>>	selectOther(Context ctx) Older versions of session-based requests accepted a "close" operator in addition to "eval".
protected Optional<ThrowingConsumer<Context>>	validateEvalMessage(RequestMessage message)

Methods inherited from class org.apache.tinkerpop.gremlin.server.op.AbstractEvalOpProcessor

evalOpInternal, select

Methods inherited from class org.apache.tinkerpop.gremlin.server.op.AbstractOpProcessor

attemptCommit, attemptRollback, determineIfSpecialException, generateResultMetaData, generateStatusAttributes, handleIterator, isForceFlushed, iterateComplete, makeFrame

Methods inherited from class java.lang.Object

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

Field Detail

OP_PROCESSOR_NAME

public static final String OP_PROCESSOR_NAME

See Also:

Constant Field Values

sessions

protected static ConcurrentHashMap<String,Session> sessions

Script engines are evaluated in a per session context where imports/scripts are isolated per session.

CONFIG_SESSION_TIMEOUT

public static final String CONFIG_SESSION_TIMEOUT

Configuration setting for how long a session will be available before it times out.

See Also:

Constant Field Values

CONFIG_PER_GRAPH_CLOSE_TIMEOUT

public static final String CONFIG_PER_GRAPH_CLOSE_TIMEOUT

Configuration setting for how long to wait in milliseconds for each configured graph to close any open transactions when the session is killed.

See Also:

Constant Field Values

CONFIG_GLOBAL_FUNCTION_CACHE_ENABLED

public static final String CONFIG_GLOBAL_FUNCTION_CACHE_ENABLED

Configuration setting that behaves as an override to the global script engine setting of the same name that is provided to the GroovyCompilerGremlinPlugin.

See Also:

Constant Field Values

DEFAULT_SESSION_TIMEOUT

public static final long DEFAULT_SESSION_TIMEOUT

Default timeout for a session is eight hours.

See Also:

Constant Field Values

DEFAULT_PER_GRAPH_CLOSE_TIMEOUT

public static final long DEFAULT_PER_GRAPH_CLOSE_TIMEOUT

Default amount of time to wait in milliseconds for each configured graph to close any open transactions when the session is killed.

See Also:

Constant Field Values

Constructor Detail

SessionOpProcessor

public SessionOpProcessor()

Method Detail

getName

public String getName()

Description copied from interface: OpProcessor

The name of the processor which requests must refer to "processor" field on a request.

init

public void init(Settings settings)

Description copied from interface: OpProcessor

Initialize the OpProcessor with settings from the server. This method should only be called once at server startup by a single thread.

selectOther

public Optional<ThrowingConsumer<Context>> selectOther(Context ctx)
                                                throws OpProcessorException

Older versions of session-based requests accepted a "close" operator in addition to "eval". This feature effectively acts as a do-nothing for 3.5.0 to allow older versions of the drivers to connect. At some point this may be removed completely. Note that closing the channel kills the session now.

Specified by:

selectOther in class AbstractEvalOpProcessor

Returns:

Throws:

OpProcessorException

getEvalOp

public ThrowingConsumer<Context> getEvalOp()

Description copied from class: AbstractEvalOpProcessor

Provides an operation for evaluating a Gremlin script.

Specified by:

getEvalOp in class AbstractEvalOpProcessor

Returns:

validateEvalMessage

protected Optional<ThrowingConsumer<Context>> validateEvalMessage(RequestMessage message)
                                                           throws OpProcessorException

Overrides:

validateEvalMessage in class AbstractEvalOpProcessor

Throws:

OpProcessorException

close

public void close()
           throws Exception

Throws:

Exception

evalOp

protected void evalOp(Context context)
               throws OpProcessorException

Throws:

OpProcessorException

getSession

protected static Session getSession(Context context,
                                    RequestMessage msg)

Examines the RequestMessage and extracts the session token. The session is then either found or a new one is created.

getBindingMaker

protected Function<Context,AbstractEvalOpProcessor.BindingSupplier> getBindingMaker(Session session)

A useful method for those extending this class, where the means for binding construction can be supplied to this class. This function is used in evalOp(Context) to create the final argument to AbstractEvalOpProcessor.evalOpInternal(Context, Supplier, BindingSupplier). In this way an extending class can use the default AbstractEvalOpProcessor.BindingSupplier which carries a lot of re-usable functionality or provide a new one to override the existing approach.

handleGraphOperation

protected void handleGraphOperation(Bytecode bytecode,
                                    Graph graph,
                                    Context context)

If Bytecode is detected to contain a "graph operation" then it gets processed by this method.

beforeProcessing

protected void beforeProcessing(Graph graph,
                                Context ctx)

onError

protected void onError(Graph graph,
                       Context ctx)

onTraversalSuccess

protected void onTraversalSuccess(Graph graph,
                                  Context ctx)

handleIterator

protected void handleIterator(Context context,
                              Iterator itty,
                              Graph graph)
                       throws InterruptedException

Throws:

InterruptedException