Class ContextSource

java.lang.Object

services.moleculer.context.ContextSource

Direct Known Subclasses:

Context, ServiceBroker

public abstract class ContextSource
extends Object

Base superclass of all objects that can send events (eg. ServiceBroker or Context).

Field Summary

Fields

Modifier and Type	Field	Description
protected final Eventbus	eventbus	Eventbus of the ServiceBroker or Context.
protected final String	nodeID	Source nodeID
protected final ServiceInvoker	serviceInvoker	Service Invoker of the ServiceBroker or Context.
protected final UidGenerator	uidGenerator	UID Generator of the ServiceBroker or Context.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	ContextSource(ServiceInvoker serviceInvoker, Eventbus eventbus, UidGenerator uidGenerator, String nodeID)

Method Summary

Modifier and Type	Method	Description
void	broadcast(String name, io.datatree.Tree payload)	Sends an event to ALL listeners from ALL event groups, who are listening this event.
void	broadcast(String name, io.datatree.Tree payload, Groups groups)	Sends an event to ALL listeners from the specified event group(s), who are listening this event.
protected void	broadcast(String name, io.datatree.Tree payload, Groups groups, PacketStream stream, CallOptions.Options opts, boolean local)
void	broadcast(String name, Object... params)	Sends an event to ALL listeners from ALL (or the specified) event group(s), who are listening this event.
void	broadcast(String name, PacketStream stream)	Sends an event to ALL listeners from ALL event groups, who are listening this event.
void	broadcast(String name, PacketStream stream, Groups groups)	Sends an event to ALL listeners from ALL event groups, who are listening this event.
void	broadcastLocal(String name, io.datatree.Tree payload)	Emits a LOCAL event to ALL listeners from ALL event groups, who are listening this event.
void	broadcastLocal(String name, io.datatree.Tree payload, Groups groups)	Emits a LOCAL event to ALL listeners from the specified event group(s), who are listening this event.
void	broadcastLocal(String name, Object... params)	Emits a LOCAL event to ALL listeners from ALL (or the specified) event group(s), who are listening this event.
io.datatree.Promise	call(String name, io.datatree.Tree params)	Calls an action (local or remote).
io.datatree.Promise	call(String name, io.datatree.Tree params, CallOptions.Options opts)	Calls an action (local or remote).
protected io.datatree.Promise	call(String name, io.datatree.Tree params, CallOptions.Options opts, PacketStream stream)
io.datatree.Promise	call(String name, Object... params)	Calls an action (local or remote).
io.datatree.Promise	call(String name, PacketStream stream)	Calls an action (local or remote).
io.datatree.Promise	call(String name, PacketStream stream, CallOptions.Options opts)	Calls an action (local or remote).
PacketStream	createStream()	Creates a stream what is suitable for transferring large files (or other "unlimited" media content) between Moleculer Nodes.
void	emit(String name, io.datatree.Tree payload)	Emits an event to ONE listener from ALL event groups, who are listening this event.
void	emit(String name, io.datatree.Tree payload, Groups groups)	Emits an event to ONE listener from the specified event group(s), who are listening this event.
protected void	emit(String name, io.datatree.Tree payload, Groups groups, PacketStream stream, CallOptions.Options opts)
void	emit(String name, Object... params)	Emits an event to ONE listener from ALL (or the specified) event group(s), who are listening this event.
void	emit(String name, PacketStream stream)	Emits an event to ONE listener from ALL event groups, who are listening this event.
void	emit(String name, PacketStream stream, Groups groups)	Emits an event to ONE listener from ALL event groups, who are listening this event.

Methods inherited from class Object

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

Field Details

eventbus

protected final Eventbus eventbus

Eventbus of the ServiceBroker or Context.

serviceInvoker

protected final ServiceInvoker serviceInvoker

Service Invoker of the ServiceBroker or Context.

uidGenerator

protected final UidGenerator uidGenerator

UID Generator of the ServiceBroker or Context.

nodeID

protected final String nodeID

Source nodeID

Constructor Details

ContextSource

protected ContextSource(ServiceInvoker serviceInvoker,
 Eventbus eventbus,
 UidGenerator uidGenerator,
 String nodeID)

Method Details

emit

public void emit(String name,
 Object... params)

Emits an event to ONE listener from ALL (or the specified) event group(s), who are listening this event. The service broker uses the default strategy of the broker for event redirection and node selection. Sample code:

ctx.emit("user.deleted", "a", 1, "b", 2);

...or send event to (one or more) listener group(s):

ctx.emit("user.deleted", "a", 1, "b", 2, Groups.of("logger"));

Parameters:

name - name of event (eg. "user.deleted")

params - list of parameter name-value pairs and an optional event group container

emit

public void emit(String name,
 io.datatree.Tree payload,
 Groups groups)

Emits an event to ONE listener from the specified event group(s), who are listening this event. The service broker uses the default strategy of the broker for event redirection and node selection. Sample code:

Tree params = new Tree();
params.put("a", true);
params.putList("b").add(1).add(2).add(3);
ctx.emit("user.created", params, Groups.of("group1", "group2"));

Parameters:

name - name of event (eg. "user.modified")

payload - Tree structure (payload of the event)

groups - event group container

emit

public void emit(String name,
 io.datatree.Tree payload)

Emits an event to ONE listener from ALL event groups, who are listening this event. The service broker uses the default strategy of the broker for event redirection and node selection. Sample code:

Tree params = new Tree();
params.put("a", true);
params.putList("b").add(1).add(2).add(3);
ctx.emit("user.modified", params);

Parameters:

name - name of event (eg. "user.created")

payload - Tree structure (payload of the event)

emit

public void emit(String name,
 PacketStream stream)

Emits an event to ONE listener from ALL event groups, who are listening this event. The service broker uses the default strategy of the broker for event redirection and node selection.

Parameters:

name - name of event (eg. "user.created")

stream - streamed data

emit

public void emit(String name,
 PacketStream stream,
 Groups groups)

Emits an event to ONE listener from ALL event groups, who are listening this event. The service broker uses the default strategy of the broker for event redirection and node selection.

Parameters:

name - name of event (eg. "user.created")

stream - streamed data

groups - event group container

broadcast

public void broadcast(String name,
 Object... params)

Sends an event to ALL listeners from ALL (or the specified) event group(s), who are listening this event. Sample code:

ctx.broadcast("user.deleted", "a", 1, "b", 2);

...or send event to (one or more) listener group(s):

ctx.broadcast("user.deleted", "a", 1, "b", 2, Groups.of("logger"));

Parameters:

name - name of event (eg. "user.deleted")

params - list of parameter name-value pairs and an optional event group container

broadcast

public void broadcast(String name,
 io.datatree.Tree payload,
 Groups groups)

Sends an event to ALL listeners from the specified event group(s), who are listening this event. Sample code:

Tree params = new Tree();
params.put("a", true);
params.putList("b").add(1).add(2).add(3);
ctx.broadcast("user.created", params, Groups.of("group1", "group2"));

Parameters:

name - name of event (eg. "user.modified")

payload - Tree structure (payload of the event)

groups - event group container

broadcast

public void broadcast(String name,
 io.datatree.Tree payload)

Sends an event to ALL listeners from ALL event groups, who are listening this event. Sample code:

Tree params = new Tree();
params.put("a", true);
params.putList("b").add(1).add(2).add(3);
ctx.broadcast("user.modified", params);

Parameters:

name - name of event (eg. "user.created")

payload - Tree structure (payload of the event)

broadcast

public void broadcast(String name,
 PacketStream stream)

Sends an event to ALL listeners from ALL event groups, who are listening this event.

Parameters:

name - name of event (eg. "user.created")

stream - streamed data

broadcast

public void broadcast(String name,
 PacketStream stream,
 Groups groups)

Sends an event to ALL listeners from ALL event groups, who are listening this event.

Parameters:

name - name of event (eg. "user.created")

stream - streamed data

groups - event group container

broadcastLocal

public void broadcastLocal(String name,
 Object... params)

Emits a LOCAL event to ALL listeners from ALL (or the specified) event group(s), who are listening this event. Sample code:

ctx.broadcastLocal("user.deleted", "a", 1, "b", 2);

...or send event to (one or more) local listener group(s):

ctx.broadcastLocal("user.deleted", "a", 1, "b", 2, Groups.of("logger"));

Parameters:

name - name of event (eg. "user.deleted")

params - list of parameter name-value pairs and an optional event group container

broadcastLocal

public void broadcastLocal(String name,
 io.datatree.Tree payload,
 Groups groups)

Emits a LOCAL event to ALL listeners from the specified event group(s), who are listening this event. Sample code:

Tree params = new Tree();
params.put("a", true);
params.putList("b").add(1).add(2).add(3);
ctx.broadcastLocal("user.created", params, Groups.of("group1", "group2"));

Parameters:

name - name of event (eg. "user.modified")

payload - Tree structure (payload of the event)

groups - event group container

broadcastLocal

public void broadcastLocal(String name,
 io.datatree.Tree payload)

Emits a LOCAL event to ALL listeners from ALL event groups, who are listening this event. Sample code:

Tree params = new Tree();
params.put("a", true);
params.putList("b").add(1).add(2).add(3);
ctx.broadcastLocal("user.modified", params);

Parameters:

name - name of event (eg. "user.created")

payload - Tree structure (payload of the event)

call

public io.datatree.Promise call(String name,
 Object... params)

Calls an action (local or remote). Sample code:

broker.call("service.action").then(ctx -> {

// Nested call:
return ctx.call("math.add", "a", 1, "b", 2);

});

...or with CallOptions:

return ctx.call("math.add", "a", 1, "b", 2, CallOptions.nodeID("node2"));

Parameters:

name - action name (eg. "math.add" in "service.action" syntax)

params - list of parameter name-value pairs and an optional CallOptions

Returns:

response Promise

call

public io.datatree.Promise call(String name,
 io.datatree.Tree params)

Calls an action (local or remote). Sample code:

broker.call("service.action").then(ctx -> {

// Nested call:
Tree params = new Tree();
params.put("a", true);
params.putList("b").add(1).add(2).add(3);
rerturn ctx.call("math.add", params);

});

Parameters:

name - action name (eg. "math.add" in "service.action" syntax)

params - Tree structure (input parameters of the method call)

Returns:

response Promise

call

public io.datatree.Promise call(String name,
 io.datatree.Tree params,
 CallOptions.Options opts)

Calls an action (local or remote).

Parameters:

name - action name (eg. "math.add" in "service.action" syntax)

params - Tree structure (input parameters of the method call)

opts - calling options (target nodeID, call timeout, number of retries)

Returns:

response Promise

call

public io.datatree.Promise call(String name,
 PacketStream stream)

Calls an action (local or remote).

Parameters:

name - action name (eg. "math.add" in "service.action" syntax)

stream - streamed data (optional)

Returns:

response Promise

call

public io.datatree.Promise call(String name,
 PacketStream stream,
 CallOptions.Options opts)

Calls an action (local or remote).

Parameters:

name - action name (eg. "math.add" in "service.action" syntax)

stream - streamed data (optional)

opts - calling options (target nodeID, call timeout, number of retries)

Returns:

response Promise

createStream

public PacketStream createStream()

Creates a stream what is suitable for transferring large files (or other "unlimited" media content) between Moleculer Nodes. Sample:

public Action send = ctx -> {
  PacketStream reqStream = ctx.createStream();
  
  ctx.call("service.action", reqStream).then(rsp -> {
  
    // Receive bytes into file
    PacketStream rspStream = (PacketStream) rsp.asObject();
    rspStream.transferTo(new File("out"));
  }
  
  // Send bytes from file
  reqStream.transferFrom(new File("in"));
}

Returns:

new stream

emit

protected void emit(String name,
 io.datatree.Tree payload,
 Groups groups,
 PacketStream stream,
 CallOptions.Options opts)

broadcast

protected void broadcast(String name,
 io.datatree.Tree payload,
 Groups groups,
 PacketStream stream,
 CallOptions.Options opts,
 boolean local)

call

protected io.datatree.Promise call(String name,
 io.datatree.Tree params,
 CallOptions.Options opts,
 PacketStream stream)