node-emberplus

This is version 2 of emberplus library. An implementation of Lawo's Ember+ control protocol for Node.
One of Node's great strengths is the ready availability of frameworks for various communication protocols and user interfaces; this module allows those to be integrated with Ember+ somewhat more easily than the reference libember C++ implementation.

This version support following ember objects : Node, Parameter, Matrix, Function, QualifiedNode, QualifiedParameter, QualifiedMatrix, QualifiedFunction.

It has been tested with EVS XT4k and Embrionix IP solutions.

The current version has added new features to the initial commit but it also modified the way the lib is used so that now it uses Promise

Server has been added in version 1.6.0.

This version doesn't have support for StreamCollection, UDP, packet stats/rate or for tree with size higher than 8M.

Example usage

Client

Get Full tree:

constEmberClient=require('node-emberplus').EmberClient;constclient=newEmberClient("10.9.8.7",9000);client.on("error",e=>{console.log(e);});client.connect()// Get Root info.then(()=>client.getDirectory())// Get a Specific Node.then(()=>client.getElementByPath("0.0.2")).then(node=>{console.log(node);})// Get a node by its path identifiers.then(()=>client.getElementByPath("path/to/node")).then(node=>{console.log(node);})// Expand entire tree under node 0.then(()=>client.expand(client.root.getElementByNumber(0))).catch((e)=>{console.log(e.stack);});

Subsribe to changes

const{EmberClient, EmberLib}=require('node-emberplus');constclient=newEmberClient(HOST,PORT);client.connect()).then(()=>client.getDirectory()).then(()=>{console.log(JSON.stringify(client.root.toJSON(),null,4));}).then(()=>client.getElementByPath("scoreMaster/router/labels/group 1")).then(node=>{// For streams, use subscribereturnclient.subscribe(node,update=>{console.log(udpate);});}).then(()=>client.getElementByPath("0.2")).then(node=>{// For non-streams a getDirectory will automatically subscribe for updatereturnclient.getDirectory(node,update=>{console.log(udpate);});})// You can also provide a callback to the getElementByPath// Be carefull that subscription will be done for all elements in the path.then(()=>client.getElementByPath("0.3",update=>{console.log(update);}));

Setting new value

client=newEmberClient(LOCALHOST,PORT);awaitclient.connect()awaitclient.getDirectory();awaitclient.getElementByPath("0.0.1");awaitclient.setValue(client.root.getElementByPath("0.0.1"),"gdnet");console.log("result",server.tree.getElementByPath("0.0.1").contents.value)returnclient.disconnect().then(()=>{console.log("disconnected")});

Invoking Function

const{EmberClient, EmberLib}=require('node-emberplus');constclient=newEmberClient(HOST,PORT);client.connect()).then(()=>client.getDirectory()).then(()=>{console.log(JSON.stringify(client.root.toJSON(),null,4));}).then(()=>client.expand(client.root.getElementByNumber(0))).then(()=>{console.log(JSON.stringify(client.root.getElementByNumber(0).toJSON(),null,4));constfuncNode=client.root.getElementByNumber(0).getElementByNumber(5).getElementByNumber(0);returnclient.invokeFunction(funcNode,[newember.FunctionArgument(EmberLib.ParameterType.integer,1),newember.FunctionArgument(EmberLib.ParameterType.integer,7)]);});

Matrix Connection

const{EmberClient, EmberLib}=require('node-emberplus');constclient=newEmberClient(HOST,PORT);client.connect().then(()=>client.getDirectory()).then(()=>client.getElementByPath("0.1.0")).then(matrix=>{console.log("Connecting source 1 to target 0);
returnclient.matrixConnect(matrix,0,[1]);}).then(()=>client.matrixDisconnect(matrix,0,[1])).then(()=>client.matrixSetConnection(matrix,0,[0,1])).then(matrix=>client.getElementByPath(matrix.getPath())).then(()=>client.disconnect());

Packet decoder

// Simple packet decoderconstDecoder=require('node-emberplus').Decoder;constfs=require("fs");fs.readFile("tree.ember",(e,data)=>{varroot=Decoder(data);});

Server

// ServerconstEmberServer=require("node-emberplus").EmberServer;constserver=newEmberServer("127.0.0.1",9000,root);server.on("error",e=>{console.log("Server Error",e);});server.on("clientError",info=>{console.log("clientError",info);});server.on("matrix-disconnect",info=>{console.log(`Client ${info.client} disconnected ${info.target} and ${info.sources}`);}server.on("matrix-connect",info=>{console.log(`Client ${info.client} connected ${info.target} and ${info.sources}`);}server.on("matrix-change",info=>{console.log(`Client ${info.client} changed ${info.target} and ${info.sources}`);}server.on("event",txt=>{console.log("event: "+txt);})server.listen().then(()=>{console.log("listening");}).catch((e)=>{console.log(e.stack);});

Construct Tree

constEmberServer=require("node-emberplus").EmberServer;const{ParameterType, FunctionArgument}=require("node-emberplus").EmberLib;consttargets=["tgt1","tgt2","tgt3"];constsources=["src1","src2","src3"];constdefaultSources=[{identifier: "t-0",value: -1,access: "readWrite"},{identifier: "t-1",value: 0,access: "readWrite"},{identifier: "t-2",value: 0,access: "readWrite"}];constlabels=function(endpoints,type){letlabels=[];for(leti=0;i<endpoints.length;i++){letendpoint=endpoints[i];letl={identifier: `${type}-${i}`};if(endpoint){l.value=endpoint;}labels.push(l);}returnlabels;};constbuildConnections=function(s,t){letconnections=[];for(leti=0;i<t.length;i++){connections.push({target: `${i}`});}returnconnections;};constjsonTree=[{// path "0"identifier: "GDNet Tree",children: [{// path "0.0"identifier: "identity",children: [{identifier: "product",value: "gdnet core"},{identifier: "company",value: "GDNet",access: "readWrite"},{identifier: "version",value: "1.2.0"},{identifier: "author",value: "dufour.gilles@gmail.com"},]},{// path "0.1"identifier: "router",children: [{// path 0.1.0identifier: "matrix",type: "oneToN",mode: "linear",targetCount: targets.length,sourceCount: sources.length,connections: buildConnections(sources,targets),labels: [{basePath: "0.1.1000",description: "primary"}]},{identifier: "labels",// path "0.1.1000"number: 1000,children: [{identifier: "targets",// Must be 1number: 1,children: labels(targets,"t")},{identifier: "sources",// Must be 2number: 2,children: labels(sources,"s")},{identifier: "group 1",children: [{identifier: "sdp A",value: "A"},{identifier: "sdp B",value: "B"}]}]},{identifier: "disconnect sources",// must be labels + 1number: 1001,children: defaultSources}]},{// path "0.2"identifier: "addFunction",func: args=>{constres=newFunctionArgument();res.type=ParameterType.integer;res.value=args[0].value+args[1].value;return[res];},arguments: [{type: ParameterType.integer,value: null,name: "arg1"},{type: ParameterType.integer,value: null,name: "arg2"}],result: [{type: ParameterType.integer,value: null,name: "changeCount"}]}]}];constroot=EmberServer.JSONtoTree(jsonTree);