services.moleculer.context

Class Context

java.lang.Object

services.moleculer.eventbus.EventEmitter

services.moleculer.context.Context

public class Context
extends EventEmitter

Field Summary

Fields

Modifier and Type	Field and Description
java.lang.String	id Unique context ID
int	level Request level (in nested-calls) - the first level is 1
java.lang.String	name Action name
CallOptions.Options	opts Calling options
io.datatree.Tree	params Request parameters (including meta)
java.lang.String	parentID Parent context ID (in nested-calls)
java.lang.String	requestID Request ID (= first context ID)
protected ServiceInvoker	serviceInvoker
long	startTime Context creation time
PacketStream	stream Streamed content

Fields inherited from class services.moleculer.eventbus.EventEmitter

eventbus

Constructor Summary

Constructors

Constructor and Description
Context(ServiceInvoker serviceInvoker, Eventbus eventbus, java.lang.String id, java.lang.String name, io.datatree.Tree params, CallOptions.Options opts, PacketStream stream)
Context(ServiceInvoker serviceInvoker, Eventbus eventbus, java.lang.String id, java.lang.String name, io.datatree.Tree params, CallOptions.Options opts, PacketStream stream, int level, java.lang.String requestID, java.lang.String parentID)
Context(java.lang.String id, java.lang.String name, io.datatree.Tree params, CallOptions.Options opts, PacketStream stream, Context parent)

Method Summary

Modifier and Type	Method and Description
io.datatree.Promise	call(java.lang.String name, java.lang.Object... params) Calls an action (local or remote).
io.datatree.Promise	call(java.lang.String name, io.datatree.Tree params) Calls an action (local or remote).
protected io.datatree.Promise	call(java.lang.String name, io.datatree.Tree params, CallOptions.Options opts) Calls an action (local or remote).
protected io.datatree.Promise	call(java.lang.String name, io.datatree.Tree params, CallOptions.Options opts, PacketStream stream) 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.

Methods inherited from class services.moleculer.eventbus.EventEmitter

broadcast, broadcast, broadcast, broadcastLocal, broadcastLocal, broadcastLocal, emit, emit, emit

Methods inherited from class java.lang.Object

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

Field Detail

id

public final java.lang.String id

Unique context ID

name

public final java.lang.String name

Action name

params

public final io.datatree.Tree params

Request parameters (including meta)

level

public final int level

Request level (in nested-calls) - the first level is 1

parentID

public final java.lang.String parentID

Parent context ID (in nested-calls)

requestID

public final java.lang.String requestID

Request ID (= first context ID)

opts

public final CallOptions.Options opts

Calling options

startTime

public final long startTime

Context creation time

stream

public PacketStream stream

Streamed content

serviceInvoker

protected final ServiceInvoker serviceInvoker

Constructor Detail

Context

public Context(ServiceInvoker serviceInvoker,
               Eventbus eventbus,
               java.lang.String id,
               java.lang.String name,
               io.datatree.Tree params,
               CallOptions.Options opts,
               PacketStream stream)

Context

public Context(java.lang.String id,
               java.lang.String name,
               io.datatree.Tree params,
               CallOptions.Options opts,
               PacketStream stream,
               Context parent)

Context

public Context(ServiceInvoker serviceInvoker,
               Eventbus eventbus,
               java.lang.String id,
               java.lang.String name,
               io.datatree.Tree params,
               CallOptions.Options opts,
               PacketStream stream,
               int level,
               java.lang.String requestID,
               java.lang.String parentID)

Method Detail

call

public io.datatree.Promise call(java.lang.String name,
                                java.lang.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(java.lang.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

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

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);
return ctx.call("math.add", params, CallOptions.nodeID("node2"));

});

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

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

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)

stream - streamed data (optional)

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