org.apache.ignite

Interface IgniteServices

All Superinterfaces:

IgniteAsyncSupport

public interface IgniteServices
extends IgniteAsyncSupport

Defines functionality necessary to deploy distributed services on the grid.

Instance of IgniteServices which spans all cluster nodes can be obtained from Ignite as follows:

 Ignite ignite = Ignition.ignite();

 IgniteServices svcs = ignite.services();
 

You can also obtain an instance of the services facade over a specific cluster group:

 // Cluster group over remote nodes (excluding the local node).
 ClusterGroup remoteNodes = ignite.cluster().forRemotes();

 // Services instance spanning all remote cluster nodes.
 IgniteServices svcs = ignite.services(remoteNodes);
 

With distributed services you can do the following:

• Automatically deploy any number of service instances on the grid.
• Automatically deploy singletons, including cluster-singleton, node-singleton, or key-affinity-singleton.
• Automatically deploy services on node start-up by specifying them in grid configuration.
• Undeploy any of the deployed services.
• Get information about service deployment topology within the grid.

Deployment From Configuration

In addition to deploying managed services by calling any of the provided deploy(...) methods, you can also automatically deploy services on startup by specifying them in IgniteConfiguration like so:

 IgniteConfiguration cfg = new IgniteConfiguration();

 ServiceConfiguration svcCfg1 = new ServiceConfiguration();

 // Cluster-wide singleton configuration.
 svcCfg1.setName("myClusterSingletonService");
 svcCfg1.setMaxPerNodeCount(1);
 svcCfg1.setTotalCount(1);
 svcCfg1.setService(new MyClusterSingletonService());

 ServiceConfiguration svcCfg2 = new ServiceConfiguration();

 // Per-node singleton configuration.
 svcCfg2.setName("myNodeSingletonService");
 svcCfg2.setMaxPerNodeCount(1);
 svcCfg2.setService(new MyNodeSingletonService());

 cfg.setServiceConfiguration(svcCfg1, svcCfg2);
 ...
 Ignition.start(cfg);
 

Load Balancing

In all cases, other than singleton service deployment, Ignite will automatically make sure that an about equal number of services are deployed on each node within the grid. Whenever cluster topology changes, Ignite will re-evaluate service deployments and may re-deploy an already deployed service on another node for better load balancing.

Fault Tolerance

Ignite guarantees that services are deployed according to specified configuration regardless of any topology changes, including node crashes.

Resource Injection

All distributed services can be injected with ignite resources. Both, field and method based injections are supported. The following ignite resources can be injected:

• IgniteInstanceResource
• LoggerResource
• SpringApplicationContextResource
• SpringResource

Refer to corresponding resource documentation for more information.

Service Example

Here is an example of how an distributed service may be implemented and deployed:

 // Simple service implementation.
 public class MyIgniteService implements Service {
      ...
      // Example of ignite resource injection. All resources are optional.
      // You should inject resources only as needed.
      @IgniteInstanceResource
      private Ignite ignite;
      ...
      @Override public void cancel(ServiceContext ctx) {
          // No-op.
      }

      @Override public void execute(ServiceContext ctx) {
          // Loop until service is cancelled.
          while (!ctx.isCancelled()) {
              // Do something.
              ...
          }
      }
  }
 ...
 IgniteServices svcs = ignite.services();

 svcs.deployClusterSingleton("mySingleton", new MyIgniteService());
 

Method Summary

Modifier and Type	Method and Description
void	cancel(String name) Cancels service deployment.
void	cancelAll() Cancels all deployed services.
void	cancelAll(Collection<String> names) Cancels services with specified names.
IgniteFuture<Void>	cancelAllAsync() Asynchronously cancels all deployed services.
IgniteFuture<Void>	cancelAllAsync(Collection<String> names) Asynchronously cancels services with specified names.
IgniteFuture<Void>	cancelAsync(String name) Asynchronously cancels service deployment.
ClusterGroup	clusterGroup() Gets the cluster group to which this IgniteServices instance belongs.
void	deploy(ServiceConfiguration cfg) Deploys multiple instances of the service on the grid according to provided configuration.
void	deployAll(Collection<ServiceConfiguration> cfgs) Deploys multiple services described by provided configurations.
IgniteFuture<Void>	deployAllAsync(Collection<ServiceConfiguration> cfgs) Asynchronously deploys multiple services described by provided configurations.
IgniteFuture<Void>	deployAsync(ServiceConfiguration cfg) Asynchronously deploys multiple instances of the service on the grid according to provided configuration.
void	deployClusterSingleton(String name, Service svc) Deploys a cluster-wide singleton service.
IgniteFuture<Void>	deployClusterSingletonAsync(String name, Service svc) Asynchronously deploys a cluster-wide singleton service.
void	deployKeyAffinitySingleton(String name, Service svc, @Nullable String cacheName, Object affKey) Deploys one instance of this service on the primary node for a given affinity key.
IgniteFuture<Void>	deployKeyAffinitySingletonAsync(String name, Service svc, @Nullable String cacheName, Object affKey) Asynchronously deploys one instance of this service on the primary node for a given affinity key.
void	deployMultiple(String name, Service svc, int totalCnt, int maxPerNodeCnt) Deploys multiple instances of the service on the grid.
IgniteFuture<Void>	deployMultipleAsync(String name, Service svc, int totalCnt, int maxPerNodeCnt) Asynchronously deploys multiple instances of the service on the grid.
void	deployNodeSingleton(String name, Service svc) Deploys a per-node singleton service.
IgniteFuture<Void>	deployNodeSingletonAsync(String name, Service svc) Asynchronously deploys a per-node singleton service.
<T> T	service(String name) Gets locally deployed service with specified name.
Collection<ServiceDescriptor>	serviceDescriptors() Gets metadata about all deployed services in the grid.
<T> T	serviceProxy(String name, Class<? super T> svcItf, boolean sticky) Gets a remote handle on the service.
<T> T	serviceProxy(String name, Class<? super T> svcItf, boolean sticky, long timeout) Gets a remote handle on the service with timeout.
<T> Collection<T>	services(String name) Gets all locally deployed services with specified name.
IgniteServices	withAsync() Deprecated.

Methods inherited from interface org.apache.ignite.lang.IgniteAsyncSupport

future, isAsync

Method Detail

clusterGroup

ClusterGroup clusterGroup()

Gets the cluster group to which this IgniteServices instance belongs.

Returns:

Cluster group to which this IgniteServices instance belongs.

deployClusterSingleton

@IgniteAsyncSupported
void deployClusterSingleton(String name,
                                                  Service svc)
                                           throws ServiceDeploymentException

Deploys a cluster-wide singleton service. Ignite will guarantee that there is always one instance of the service in the cluster. In case if grid node on which the service was deployed crashes or stops, Ignite will automatically redeploy it on another node. However, if the node on which the service is deployed remains in topology, then the service will always be deployed on that node only, regardless of topology changes.

Note that in case of topology changes, due to network delays, there may be a temporary situation when a singleton service instance will be active on more than one node (e.g. crash detection delay).

This method is analogous to calling deployMultiple(name, svc, 1, 1) method.

Parameters:

name - Service name.

svc - Service instance.

Throws:

ServiceDeploymentException - If failed to deploy service.

deployClusterSingletonAsync

IgniteFuture<Void> deployClusterSingletonAsync(String name,
                                               Service svc)

Asynchronously deploys a cluster-wide singleton service. Ignite will guarantee that there is always one instance of the service in the cluster. In case if grid node on which the service was deployed crashes or stops, Ignite will automatically redeploy it on another node. However, if the node on which the service is deployed remains in topology, then the service will always be deployed on that node only, regardless of topology changes.

Note that in case of topology changes, due to network delays, there may be a temporary situation when a singleton service instance will be active on more than one node (e.g. crash detection delay).

This method is analogous to calling deployMultipleAsync(name, svc, 1, 1) method.

Parameters:

name - Service name.

svc - Service instance.

Returns:

a Future representing pending completion of the operation.

deployNodeSingleton

@IgniteAsyncSupported
void deployNodeSingleton(String name,
                                               Service svc)
                                        throws ServiceDeploymentException

Deploys a per-node singleton service. Ignite will guarantee that there is always one instance of the service running on each node. Whenever new nodes are started within the underlying cluster group, Ignite will automatically deploy one instance of the service on every new node.

This method is analogous to calling deployMultiple(name, svc, 0, 1) method.

Parameters:

name - Service name.

svc - Service instance.

Throws:

ServiceDeploymentException - If failed to deploy service.

deployNodeSingletonAsync

IgniteFuture<Void> deployNodeSingletonAsync(String name,
                                            Service svc)

Asynchronously deploys a per-node singleton service. Ignite will guarantee that there is always one instance of the service running on each node. Whenever new nodes are started within the underlying cluster group, Ignite will automatically deploy one instance of the service on every new node.

This method is analogous to calling deployMultipleAsync(name, svc, 0, 1) method.

Parameters:

name - Service name.

svc - Service instance.

Returns:

a Future representing pending completion of the operation.

deployKeyAffinitySingleton

@IgniteAsyncSupported
void deployKeyAffinitySingleton(String name,
                                                      Service svc,
                                                      @Nullable
                                                      @Nullable String cacheName,
                                                      Object affKey)
                                               throws ServiceDeploymentException

Deploys one instance of this service on the primary node for a given affinity key. Whenever topology changes and primary node assignment changes, Ignite will always make sure that the service is undeployed on the previous primary node and deployed on the new primary node.

Note that in case of topology changes, due to network delays, there may be a temporary situation when a service instance will be active on more than one node (e.g. crash detection delay).

This method is analogous to the invocation of deploy(org.apache.ignite.services.ServiceConfiguration) method as follows:

     ServiceConfiguration cfg = new ServiceConfiguration();

     cfg.setName(name);
     cfg.setService(svc);
     cfg.setCacheName(cacheName);
     cfg.setAffinityKey(affKey);
     cfg.setTotalCount(1);
     cfg.setMaxPerNodeCount(1);

     ignite.services().deploy(cfg);
 

Parameters:

name - Service name.

svc - Service instance.

cacheName - Name of the cache on which affinity for key should be calculated, null for default cache.

affKey - Affinity cache key.

Throws:

ServiceDeploymentException - If failed to deploy service.

deployKeyAffinitySingletonAsync

IgniteFuture<Void> deployKeyAffinitySingletonAsync(String name,
                                                   Service svc,
                                                   @Nullable
                                                   @Nullable String cacheName,
                                                   Object affKey)

Asynchronously deploys one instance of this service on the primary node for a given affinity key. Whenever topology changes and primary node assignment changes, Ignite will always make sure that the service is undeployed on the previous primary node and deployed on the new primary node.

Note that in case of topology changes, due to network delays, there may be a temporary situation when a service instance will be active on more than one node (e.g. crash detection delay).

This method is analogous to the invocation of deployAsync(org.apache.ignite.services.ServiceConfiguration) method as follows:

     ServiceConfiguration cfg = new ServiceConfiguration();

     cfg.setName(name);
     cfg.setService(svc);
     cfg.setCacheName(cacheName);
     cfg.setAffinityKey(affKey);
     cfg.setTotalCount(1);
     cfg.setMaxPerNodeCount(1);

     ignite.services().deployAsync(cfg);
 

Parameters:

name - Service name.

svc - Service instance.

cacheName - Name of the cache on which affinity for key should be calculated, null for default cache.

affKey - Affinity cache key.

Returns:

a Future representing pending completion of the operation.

deployMultiple

@IgniteAsyncSupported
void deployMultiple(String name,
                                          Service svc,
                                          int totalCnt,
                                          int maxPerNodeCnt)
                                   throws ServiceDeploymentException

Deploys multiple instances of the service on the grid. Ignite will deploy a maximum amount of services equal to 'totalCnt' parameter making sure that there are no more than 'maxPerNodeCnt' service instances running on each node. Whenever topology changes, Ignite will automatically rebalance the deployed services within cluster to make sure that each node will end up with about equal number of deployed instances whenever possible.

Note that at least one of 'totalCnt' or 'maxPerNodeCnt' parameters must have value greater than 0.

This method is analogous to the invocation of deploy(org.apache.ignite.services.ServiceConfiguration) method as follows:

     ServiceConfiguration cfg = new ServiceConfiguration();

     cfg.setName(name);
     cfg.setService(svc);
     cfg.setTotalCount(totalCnt);
     cfg.setMaxPerNodeCount(maxPerNodeCnt);

     ignite.services().deploy(cfg);
 

Parameters:

name - Service name.

svc - Service instance.

totalCnt - Maximum number of deployed services in the grid, 0 for unlimited.

maxPerNodeCnt - Maximum number of deployed services on each node, 0 for unlimited.

Throws:

ServiceDeploymentException - If failed to deploy service.

deployMultipleAsync

IgniteFuture<Void> deployMultipleAsync(String name,
                                       Service svc,
                                       int totalCnt,
                                       int maxPerNodeCnt)

Asynchronously deploys multiple instances of the service on the grid. Ignite will deploy a maximum amount of services equal to 'totalCnt' parameter making sure that there are no more than 'maxPerNodeCnt' service instances running on each node. Whenever topology changes, Ignite will automatically rebalance the deployed services within cluster to make sure that each node will end up with about equal number of deployed instances whenever possible.

Note that at least one of 'totalCnt' or 'maxPerNodeCnt' parameters must have value greater than 0.

This method is analogous to the invocation of deployAsync(org.apache.ignite.services.ServiceConfiguration) method as follows:

     ServiceConfiguration cfg = new ServiceConfiguration();

     cfg.setName(name);
     cfg.setService(svc);
     cfg.setTotalCount(totalCnt);
     cfg.setMaxPerNodeCount(maxPerNodeCnt);

     ignite.services().deployAsync(cfg);
 

Parameters:

name - Service name.

svc - Service instance.

totalCnt - Maximum number of deployed services in the grid, 0 for unlimited.

maxPerNodeCnt - Maximum number of deployed services on each node, 0 for unlimited.

Returns:

a Future representing pending completion of the operation.

deploy

@IgniteAsyncSupported
void deploy(ServiceConfiguration cfg)
                           throws ServiceDeploymentException

Deploys multiple instances of the service on the grid according to provided configuration. Ignite will deploy a maximum amount of services equal to cfg.getTotalCount() parameter making sure that there are no more than cfg.getMaxPerNodeCount() service instances running on each node. Whenever topology changes, Ignite will automatically rebalance the deployed services within cluster to make sure that each node will end up with about equal number of deployed instances whenever possible.

If cfg.getAffinityKey() is not null, then Ignite will deploy the service on the primary node for given affinity key. The affinity will be calculated on the cache with cfg.getCacheName() name.

If cfg.getNodeFilter() is not null, then Ignite will deploy service on all grid nodes for which the provided filter evaluates to true. The node filter will be checked in addition to the underlying cluster group filter, or the whole grid, if the underlying cluster group includes all the cluster nodes.

Note that at least one of 'totalCnt' or 'maxPerNodeCnt' parameters must have value greater than 0.

Here is an example of creating service deployment configuration:

     ServiceConfiguration cfg = new ServiceConfiguration();

     cfg.setName(name);
     cfg.setService(svc);
     cfg.setTotalCount(0); // Unlimited.
     cfg.setMaxPerNodeCount(2); // Deploy 2 instances of service on each node.

     ignite.services().deploy(cfg);
 

Parameters:

cfg - Service configuration.

Throws:

ServiceDeploymentException - If failed to deploy service.

deployAsync

IgniteFuture<Void> deployAsync(ServiceConfiguration cfg)

Asynchronously deploys multiple instances of the service on the grid according to provided configuration. Ignite will deploy a maximum amount of services equal to cfg.getTotalCount() parameter making sure that there are no more than cfg.getMaxPerNodeCount() service instances running on each node. Whenever topology changes, Ignite will automatically rebalance the deployed services within cluster to make sure that each node will end up with about equal number of deployed instances whenever possible.

If cfg.getAffinityKey() is not null, then Ignite will deploy the service on the primary node for given affinity key. The affinity will be calculated on the cache with cfg.getCacheName() name.

If cfg.getNodeFilter() is not null, then Ignite will deploy service on all grid nodes for which the provided filter evaluates to true. The node filter will be checked in addition to the underlying cluster group filter, or the whole grid, if the underlying cluster group includes all the cluster nodes.

Note that at least one of 'totalCnt' or 'maxPerNodeCnt' parameters must have value greater than 0.

Here is an example of creating service deployment configuration:

     ServiceConfiguration cfg = new ServiceConfiguration();

     cfg.setName(name);
     cfg.setService(svc);
     cfg.setTotalCount(0); // Unlimited.
     cfg.setMaxPerNodeCount(2); // Deploy 2 instances of service on each node.

     ignite.services().deployAsync(cfg);
 

Parameters:

cfg - Service configuration.

Returns:

a Future representing pending completion of the operation.

deployAll

void deployAll(Collection<ServiceConfiguration> cfgs)
        throws ServiceDeploymentException

Deploys multiple services described by provided configurations. Depending on specified parameters, multiple instances of the same service may be deployed (see ServiceConfiguration). Whenever topology changes, Ignite will automatically rebalance the deployed services within cluster to make sure that each node will end up with about equal number of deployed instances whenever possible. If deployment of some of the provided services fails, then ServiceDeploymentException containing a list of failed services will be thrown. It is guaranteed that all services that were provided to this method and are not present in the list of failed services are successfully deployed by the moment of the exception being thrown. Note that if exception is thrown, then partial deployment may have occurred.

Parameters:

cfgs - Collection of service configurations to be deployed.

Throws:

ServiceDeploymentException - If failed to deploy services.

See Also:

deploy(ServiceConfiguration), deployAllAsync(Collection)

deployAllAsync

IgniteFuture<Void> deployAllAsync(Collection<ServiceConfiguration> cfgs)

Asynchronously deploys multiple services described by provided configurations. Depending on specified parameters, multiple instances of the same service may be deployed (see ServiceConfiguration). Whenever topology changes, Ignite will automatically rebalance the deployed services within cluster to make sure that each node will end up with about equal number of deployed instances whenever possible. If deployment of some of the provided services fails, then ServiceDeploymentException containing a list of failed services will be thrown from get() method of the returned future. It is guaranteed that all services, that were provided to this method and are not present in the list of failed services, are successfully deployed by the moment of the exception being thrown. Note that if exception is thrown, then partial deployment may have occurred.

Parameters:

cfgs - Collection of service configurations to be deployed.

Returns:

a Future representing pending completion of the operation.

See Also:

deploy(ServiceConfiguration), deployAll(Collection)

cancel

@IgniteAsyncSupported
void cancel(String name)
                           throws IgniteException

Cancels service deployment. If a service with specified name was deployed on the grid, then Service.cancel(org.apache.ignite.services.ServiceContext) method will be called on it.

Note that Ignite cannot guarantee that the service exits from Service.execute(org.apache.ignite.services.ServiceContext) method whenever Service.cancel(org.apache.ignite.services.ServiceContext) is called. It is up to the user to make sure that the service code properly reacts to cancellations.

Supports asynchronous execution (see IgniteAsyncSupport).

Parameters:

name - Name of service to cancel.

Throws:

IgniteException - If failed to cancel service.

cancelAsync

IgniteFuture<Void> cancelAsync(String name)

Asynchronously cancels service deployment. If a service with specified name was deployed on the grid, then Service.cancel(org.apache.ignite.services.ServiceContext) method will be called on it.

Note that Ignite cannot guarantee that the service exits from Service.execute(org.apache.ignite.services.ServiceContext) method whenever Service.cancel(org.apache.ignite.services.ServiceContext) is called. It is up to the user to make sure that the service code properly reacts to cancellations.

Parameters:

name - Name of service to cancel.

Returns:

a Future representing pending completion of the operation.

cancelAll

@IgniteAsyncSupported
void cancelAll(Collection<String> names)
                              throws IgniteException

Cancels services with specified names.

Note that depending on user logic, it may still take extra time for a service to finish execution, even after it was cancelled.

Supports asynchronous execution (see IgniteAsyncSupport).

Parameters:

names - Names of services to cancel.

Throws:

IgniteException - If failed to cancel services.

cancelAllAsync

IgniteFuture<Void> cancelAllAsync(Collection<String> names)

Asynchronously cancels services with specified names.

Note that depending on user logic, it may still take extra time for a service to finish execution, even after it was cancelled.

Parameters:

names - Names of services to cancel.

Returns:

a Future representing pending completion of the operation.

cancelAll

@IgniteAsyncSupported
void cancelAll()
                              throws IgniteException

Cancels all deployed services.

Note that depending on user logic, it may still take extra time for a service to finish execution, even after it was cancelled.

Supports asynchronous execution (see IgniteAsyncSupport).

Throws:

IgniteException - If failed to cancel services.

cancelAllAsync

IgniteFuture<Void> cancelAllAsync()

Asynchronously cancels all deployed services.

Note that depending on user logic, it may still take extra time for a service to finish execution, even after it was cancelled.

Returns:

a Future representing pending completion of the operation.

serviceDescriptors

Collection<ServiceDescriptor> serviceDescriptors()

Gets metadata about all deployed services in the grid.

Returns:

Metadata about all deployed services in the grid.

service

<T> T service(String name)

Gets locally deployed service with specified name.

Type Parameters:

T - Service type

Parameters:

name - Service name.

Returns:

Deployed service with specified name.

services

<T> Collection<T> services(String name)

Gets all locally deployed services with specified name.

Type Parameters:

T - Service type.

Parameters:

name - Service name.

Returns:

all deployed services with specified name.

serviceProxy

<T> T serviceProxy(String name,
                   Class<? super T> svcItf,
                   boolean sticky)
            throws IgniteException

Gets a remote handle on the service. If service is available locally, then local instance is returned, otherwise, a remote proxy is dynamically created and provided for the specified service.

Parameters:

name - Service name.

svcItf - Interface for the service.

sticky - Whether or not Ignite should always contact the same remote service or try to load-balance between services.

Returns:

Either proxy over remote service or local service if it is deployed locally.

Throws:

IgniteException - If failed to create service proxy.

serviceProxy

<T> T serviceProxy(String name,
                   Class<? super T> svcItf,
                   boolean sticky,
                   long timeout)
            throws IgniteException

Gets a remote handle on the service with timeout. If service is available locally, then local instance is returned and timeout ignored, otherwise, a remote proxy is dynamically created and provided for the specified service.

Parameters:

name - Service name.

svcItf - Interface for the service.

sticky - Whether or not Ignite should always contact the same remote service or try to load-balance between services.

timeout - If greater than 0 created proxy will wait for service availability only specified time, and will limit remote service invocation time.

Returns:

Either proxy over remote service or local service if it is deployed locally.

Throws:

IgniteException - If failed to create service proxy.

withAsync

@Deprecated
IgniteServices withAsync()

Deprecated.

Gets instance of this component with asynchronous mode enabled.

Specified by:

withAsync in interface IgniteAsyncSupport

Returns:

Instance of this component with asynchronous mode enabled.