Interface ServiceDiscovery
-
public interface ServiceDiscoveryService Discovery main entry point.The service discovery is an infrastructure that let you publish and find `services`. A `service` is a discoverable functionality. It can be qualified by its type, metadata, and location. So a `service` can be a database, a service proxy, a HTTP endpoint. It does not have to be a vert.x entity, but can be anything. Each service is described by a
Record.The service discovery implements the interactions defined in the service-oriented computing. And to some extend, also provides the dynamic service-oriented computing interaction. So, application can react to arrival and departure of services.
A service provider can:
* publish a service record * un-publish a published record * update the status of a published service (down, out of service...)
A service consumer can:
* lookup for services * bind to a selected service (it gets a
ServiceReference) and use it * release the service once the consumer is done with it * listen for arrival, departure and modification of services.Consumer would 1) lookup for service record matching their need, 2) retrieve the
ServiceReferencethat give access to the service, 3) get a service object to access the service, 4) release the service object once done.A state above, the central piece of information shared by the providers and consumers are
records.Providers and consumers must create their own
ServiceDiscoveryinstance. These instances are collaborating in background (distributed structure) to keep the set of services in sync.- Author:
- Clement Escoffier
-
-
Field Summary
Fields Modifier and Type Field Description static StringEVENT_IDConstant for id field of usage events.static StringEVENT_RECORDConstant for record field of usage events.static StringEVENT_TYPEConstant for type field of usage events.static StringEVENT_TYPE_BINDConstant for event type `Bind`.static StringEVENT_TYPE_RELEASEConstant for event type `Release`.
-
Method Summary
All Methods Static Methods Instance Methods Abstract Methods Modifier and Type Method Description Set<ServiceReference>bindings()voidclose()Closes the service discoverystatic ServiceDiscoverycreate(Vertx vertx)Creates a new instance ofServiceDiscoveryusing the default configuration.static ServiceDiscoverycreate(Vertx vertx, ServiceDiscoveryOptions options)Creates an instance ofServiceDiscovery.Future<Record>getRecord(JsonObject filter)Lookups for a single record.Future<Record>getRecord(String id)Looks up for a single record by its registrationid.Future<Record>getRecord(Function<Record,Boolean> filter)Lookups for a single record.Future<Record>getRecord(Function<Record,Boolean> filter, boolean includeOutOfService)Lookups for a single record.Future<List<Record>>getRecords(JsonObject filter)Lookups for a set of records.Future<List<Record>>getRecords(Function<Record,Boolean> filter)Lookups for a set of records.Future<List<Record>>getRecords(Function<Record,Boolean> filter, boolean includeOutOfService)Lookups for a set of records.ServiceReferencegetReference(Record record)Gets a service reference from the given record.ServiceReferencegetReferenceWithConfiguration(Record record, JsonObject configuration)Gets a service reference from the given record, the reference is configured with the given json object.ServiceDiscoveryOptionsoptions()Future<Record>publish(Record record)Publishes a record.Future<Void>registerServiceExporter(ServiceExporter exporter, JsonObject configuration)Registers a discovery bridge.Future<Void>registerServiceImporter(ServiceImporter importer, JsonObject configuration)Registers a discovery service importer.booleanrelease(ServiceReference reference)Releases the service reference.static voidreleaseServiceObject(ServiceDiscovery discovery, Object svcObject)Release the service object retrieved usinggetmethods from the service type interface.Future<Void>unpublish(String id)Un-publishes a record.Future<Record>update(Record record)Updates the given record.
-
-
-
Field Detail
-
EVENT_TYPE
static final String EVENT_TYPE
Constant for type field of usage events.- See Also:
EVENT_TYPE_BIND,EVENT_TYPE_RELEASE, Constant Field Values
-
EVENT_TYPE_BIND
static final String EVENT_TYPE_BIND
Constant for event type `Bind`.- See Also:
EVENT_TYPE, Constant Field Values
-
EVENT_TYPE_RELEASE
static final String EVENT_TYPE_RELEASE
Constant for event type `Release`.- See Also:
EVENT_TYPE, Constant Field Values
-
EVENT_RECORD
static final String EVENT_RECORD
Constant for record field of usage events.- See Also:
- Constant Field Values
-
EVENT_ID
static final String EVENT_ID
Constant for id field of usage events.- See Also:
- Constant Field Values
-
-
Method Detail
-
create
static ServiceDiscovery create(Vertx vertx, ServiceDiscoveryOptions options)
Creates an instance ofServiceDiscovery.- Parameters:
vertx- the vert.x instanceoptions- the discovery options- Returns:
- the created service discovery instance.
-
create
static ServiceDiscovery create(Vertx vertx)
Creates a new instance ofServiceDiscoveryusing the default configuration.- Parameters:
vertx- the vert.x instance- Returns:
- the created instance
-
getReference
ServiceReference getReference(Record record)
Gets a service reference from the given record.- Parameters:
record- the chosen record- Returns:
- the service reference, that allows retrieving the service object. Once called the service reference is cached, and need to be released.
-
getReferenceWithConfiguration
ServiceReference getReferenceWithConfiguration(Record record, JsonObject configuration)
Gets a service reference from the given record, the reference is configured with the given json object.- Parameters:
record- the chosen recordconfiguration- the configuration- Returns:
- the service reference, that allows retrieving the service object. Once called the service reference is cached, and need to be released.
-
release
boolean release(ServiceReference reference)
Releases the service reference.- Parameters:
reference- the reference to release, must not benull- Returns:
- whether or not the reference has been released.
-
registerServiceImporter
Future<Void> registerServiceImporter(ServiceImporter importer, JsonObject configuration)
Registers a discovery service importer. Importers let you integrate other discovery technologies in this service discovery.- Parameters:
importer- the service importerconfiguration- the optional configuration- Returns:
- a future notified when the importer has finished its initialization and initial imports
-
registerServiceExporter
Future<Void> registerServiceExporter(ServiceExporter exporter, JsonObject configuration)
Registers a discovery bridge. Exporters let you integrate other discovery technologies in this service discovery.- Parameters:
exporter- the service exporterconfiguration- the optional configuration- Returns:
- a future notified when the exporter has been correctly initialized.
-
close
void close()
Closes the service discovery
-
publish
Future<Record> publish(Record record)
Publishes a record.- Parameters:
record- the record- Returns:
- a future notified when the operation has completed (successfully or not). In case of success, the passed record has a registration id required to modify and un-register the service.
-
unpublish
Future<Void> unpublish(String id)
Un-publishes a record.- Parameters:
id- the registration id- Returns:
- a future notified when the operation has completed (successfully or not).
-
getRecord
Future<Record> getRecord(JsonObject filter)
Lookups for a single record.Filters are expressed using a Json object. Each entry of the given filter will be checked against the record. All entry must match exactly the record. The entry can use the special "*" value to denotes a requirement on the key, but not on the value.
Let's take some example:
{ "name" = "a" } => matches records with name set fo "a" { "color" = "*" } => matches records with "color" set { "color" = "red" } => only matches records with "color" set to "red" { "color" = "red", "name" = "a"} => only matches records with name set to "a", and color set to "red"If the filter is not set (
nullor empty), it accepts all records.This method returns the first matching record.
- Parameters:
filter- the filter.- Returns:
- a future notified when the lookup has been completed. When there are no matching record, the
operation succeeds, but the async result has no result (
null).
-
getRecord
Future<Record> getRecord(String id)
Looks up for a single record by its registrationid.When there are no matching record, the operation succeeds, but the async result has no result (
null).- Parameters:
id- the registration id- Returns:
- a future notified when the lookup has been completed
- See Also:
Record.getRegistration()
-
getRecord
Future<Record> getRecord(Function<Record,Boolean> filter)
Lookups for a single record.The filter is a
Functiontaking aRecordas argument and returning a boolean. You should see it as anacceptmethod of a filter. This method return a record passing the filter.This method only looks for records with a
UPstatus.- Parameters:
filter- the filter, must not benull. To return all records, use a function accepting all records- Returns:
- a future notified when the lookup has been completed. When there are no matching record, the operation succeed, but the async result has no result.
-
getRecord
Future<Record> getRecord(Function<Record,Boolean> filter, boolean includeOutOfService)
Lookups for a single record.The filter is a
Functiontaking aRecordas argument and returning a boolean. You should see it as anacceptmethod of a filter. This method return a record passing the filter.Unlike
getRecord(Function), this method may accept records with aOUT OF SERVICEstatus, if theincludeOutOfServiceparameter is set totrue.- Parameters:
filter- the filter, must not benull. To return all records, use a function accepting all recordsincludeOutOfService- whether or not the filter acceptsOUT OF SERVICErecords- Returns:
- a future notified when the lookup has been completed. When there are no matching record, the operation succeed, but the async result has no result.
-
getRecords
Future<List<Record>> getRecords(JsonObject filter)
Lookups for a set of records. UnlikegetRecord(JsonObject), this method returns all matching records.- Parameters:
filter- the filter - seegetRecord(JsonObject)- Returns:
- a future notified when the lookup has been completed. When there are no matching record, the operation succeed, but the async result has an empty list as result.
-
getRecords
Future<List<Record>> getRecords(Function<Record,Boolean> filter)
Lookups for a set of records. UnlikegetRecord(Function), this method returns all matching records.The filter is a
Functiontaking aRecordas argument and returning a boolean. You should see it as anacceptmethod of a filter. This method return a record passing the filter.This method only looks for records with a
UPstatus.- Parameters:
filter- the filter, must not benull. To return all records, use a function accepting all records- Returns:
- a future notified when the lookup has been completed. When there are no matching record, the operation succeed, but the async result has an empty list as result.
-
getRecords
Future<List<Record>> getRecords(Function<Record,Boolean> filter, boolean includeOutOfService)
Lookups for a set of records. UnlikegetRecord(Function), this method returns all matching records.The filter is a
Functiontaking aRecordas argument and returning a boolean. You should see it as anacceptmethod of a filter. This method return a record passing the filter.Unlike
getRecords(Function), this method may accept records with aOUT OF SERVICEstatus, if theincludeOutOfServiceparameter is set totrue.- Parameters:
filter- the filter, must not benull. To return all records, use a function accepting all recordsincludeOutOfService- whether the filter acceptsOUT OF SERVICErecords- Returns:
- a future notified when the lookup has been completed. When there are no matching record, the operation succeed, but the async result has an empty list as result.
-
update
Future<Record> update(Record record)
Updates the given record. The record must has been published, and has it's registration id set.- Parameters:
record- the updated record- Returns:
- a future notified when the lookup has been completed.
-
bindings
Set<ServiceReference> bindings()
- Returns:
- the set of service references retrieved by this service discovery.
-
options
ServiceDiscoveryOptions options()
- Returns:
- the discovery options. Modifying the returned object would not update the discovery service configuration. This object should be considered as read-only.
-
releaseServiceObject
static void releaseServiceObject(ServiceDiscovery discovery, Object svcObject)
Release the service object retrieved usinggetmethods from the service type interface. It searches for the reference associated with the given object and release it.- Parameters:
discovery- the service discoverysvcObject- the service object
-
-