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				+import * as grpc from '@grpc/grpc-js'; 
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				+import { Observable, Subject, Subscription } from "rxjs"; 
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				+import { Message, ConnectionAttribute, GrpcConnectionType, ConnectionState, MessageLog, ConnectionStatus, StreamAttribute, State } from "../interfaces/general.interface"; 
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				+import { Status } from '@grpc/grpc-js/build/src/constants'; 
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				+import { message_proto } from './protos/server.proto' 
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				+import * as _ from 'lodash' 
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				+export class GrpcServiceMethod { 
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				+    private connectionAttributes: ConnectionAttribute[] = [] 
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				+    private updateConnectionStatusFlag: boolean = false 
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				+    private server: grpc.Server | any 
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				+    private messageToBeSendOver: Message | any 
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				+    private clientRequest: Subject<ConnectionAttribute> = new Subject() 
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				+    private localServerStatus: Subject<any> = new Subject() 
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				+ 
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				+    public async create(connectionAttribute: ConnectionAttribute, connectionAttributes: ConnectionAttribute[]): Promise<any> { 
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				+        this.connectionAttributes = connectionAttributes 
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				+        return new Promise((resolve, reject) => { 
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				+            this.createGrpcInstance({ instanceType: 'server' }, connectionAttribute) 
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				+            this.createGrpcInstance({ instanceType: 'client' }, connectionAttribute) 
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				+            resolve('Just putting it here for now....') 
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				+        }) 
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				+    } 
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				+ 
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				+    private async createGrpcInstance(grpcType: GrpcConnectionType, connectionAttribute: ConnectionAttribute) { 
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				+        // Reconnection Logic here 
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				+        while (true) { 
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				+            try { 
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				+                let recreatePromise = new Promise((resolve) => { 
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				+                    if (grpcType.instanceType == 'server' && !this.server) { 
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				+                        this.createServerStreamingServer(connectionAttribute).then(() => { 
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				+                            resolve('recreate') 
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				+                        }) 
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				+                    } 
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				+                    if (grpcType.instanceType == 'client') { 
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				+                        this.createServerStreamingClient(connectionAttribute).then(() => { 
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				+                            resolve('recreate') 
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				+                        }) 
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				+                    } 
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				+                }) 
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				+                await recreatePromise 
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				+            } catch (error) { 
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				+                console.error('Connection attempt failed:', error); 
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				+            } 
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				+            await new Promise(resolve => setTimeout(resolve, 1000)); // Wait for 1 second before the next attempt 
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				+            // timeout generate message to trigger this reconnection 
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				+        } 
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				+    } 
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				+ 
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				+    // Create Server Instance to stream all application Outgoing messages     
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				+    public async createServerStreamingServer(connectionAttribute: ConnectionAttribute): Promise<any> { // '0.0.0.0:3001' 
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				+        return new Promise((resolve, reject) => { 
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				+            try { 
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				+                let statusChain: State = 1 
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				+                if (statusChain == 1) { 
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				+                    // Bind and start the server 
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				+                    this.server = new grpc.Server() 
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				+                    this.server.bindAsync(connectionAttribute.outGoing.serverUrl, grpc.ServerCredentials.createInsecure(), () => { 
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				+                        console.log(`gRPC server is running on ${connectionAttribute.outGoing.serverUrl}`); 
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				+                        this.server.start(); 
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				+                    }); 
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				+                    this.localServerStatus.next({ 
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				+                        connectionStatus: 'ON', 
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				+                        connectionID: connectionAttribute.ConnectionID.local, 
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				+                        message: `${connectionAttribute.outGoing.serverUrl} started.` 
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				+                    }) 
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				+                } 
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				+ 
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				+                if (statusChain == 1 && !this.server) { 
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				+                    this.server.addService(message_proto.Message.service, { 
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				+                        HandleMessage: (call) => { 
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				+                            /// add a checking for standard message request 
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				+                            let clientInfo: ConnectionAttribute = JSON.parse(call.request.message) 
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				+                            if (this.isConnectionAttribute(clientInfo)) { 
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				+                                // this.clientRequest.next(clientInfo) 
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				+                                console.log(`Initializing stream. Opening Channel... Confirmation from ${call.request.id}`) 
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				+                                let result: ConnectionAttribute | undefined = this.connectionAttributes.find(connectionAttribute => connectionAttribute.ConnectionID.local = clientInfo.ConnectionID.remote) 
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				+                                if (!result) { 
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				+                                    console.log(`No connectionID match. This should be new connection...`) 
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				+                                    let subscription: Subscription = connectionAttribute.outGoing.MessageToBePublished!.subscribe({ 
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				+                                        next: (response: Message) => { 
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				+                                            console.log(`Sending from GRPC server: ${(response.message as MessageLog).appData.msgId} `) 
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				+                                            let message = { 
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				+                                                id: response.id, 
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				+                                                message: JSON.stringify(response.message) 
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				+                                            } 
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				+                                            call.write(message) 
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				+                                        }, 
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				+                                        error: err => { 
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				+                                            console.error(err) 
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				+                                            subscription.unsubscribe() 
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				+                                            resolve('') 
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				+                                        }, 
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				+                                        complete: () => { 
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				+                                            console.log(`Stream response completed for ${call.request.id}`) 
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				+                                            subscription.unsubscribe() 
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				+                                            resolve('') 
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				+                                        } 
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				+                                    }) 
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				+                                    let report: ConnectionState = { 
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				+                                        status: 'DIRECT_PUBLISH' 
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				+                                    } 
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				+                                    connectionAttribute.connectionStatus!.next(report) 
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				+                                } 
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				+                                if (result && result.outGoing.connectionState == `OFF`) { 
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				+                                    // reassign previously matched buffer 
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				+                                    console.log(`Connection info found in array matched. Assigning buffer....`) 
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				+                                    let subscription: Subscription = result.outGoing.MessageToBePublished!.subscribe({ 
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				+                                        next: (response: Message) => { 
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				+                                            console.log(`Sending from GRPC server: ${(response.message as MessageLog).appData.msgId} `) 
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				+                                            let message = { 
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				+                                                id: response.id, 
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				+                                                message: JSON.stringify(response.message) 
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				+                                            } 
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				+                                            call.write(message) 
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				+                                        }, 
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				+                                        error: err => { 
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				+                                            console.error(err) 
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				+                                            subscription.unsubscribe() 
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				+                                            resolve('') 
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				+                                        }, 
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				+                                        complete: () => { 
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				+                                            console.log(`Stream response completed for ${call.request.id}`) 
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				+                                            subscription.unsubscribe() 
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				+                                            resolve('') 
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				+                                        } 
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				+                                    }) 
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				+                                    let report: ConnectionState = { 
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				+                                        status: 'DIRECT_PUBLISH' 
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				+                                    } 
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				+                                    result.connectionStatus!.next(report) 
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				+                                } 
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				+ 
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				+                            } else { 
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				+                                console.error(`INVALID REQUEST! Client request does not fulfill criteria`) 
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				+                            } 
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				+                        }, 
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				+                        Check: (_, callback) => { 
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				+                            // for now it is just sending the status message over to tell the client it is alive 
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				+                            // For simplicity, always return "SERVING" as status 
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				+                            callback(null, { status: 'SERVING' }); 
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				+                        }, 
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				+                    }); 
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				+                } 
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				+            } 
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				+            catch (error) { 
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				+                resolve(error) 
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				+            } 
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				+        }) 
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				+    } 
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				+ 
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				+    // Send a request over to the other server to open a channel for this server to emit/stream messages over 
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				+    public async createServerStreamingClient(connectionAttribute: ConnectionAttribute): Promise<string> { 
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				+        return new Promise(async (resolve, reject) => { 
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				+            const client = new message_proto.Message(connectionAttribute.inComing.serverUrl, grpc.credentials.createInsecure()); 
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				+            let localInfo: ConnectionAttribute = { // need to make a new copy where it doesn't reference the subjects, otherwise circular ref error 
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				+                ConnectionID: connectionAttribute.ConnectionID, 
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				+                outGoing: { 
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				+                    StreamID: connectionAttribute.outGoing.StreamID, 
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				+                    PublisherID: connectionAttribute.outGoing.PublisherID, 
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				+                    SubscriberID: connectionAttribute.outGoing.SubscriberID, 
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				+                    serverUrl: connectionAttribute.outGoing.serverUrl, 
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				+                    MessageToBePublished: null, 
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				+                    MessageToBeReceived: null 
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				+                }, 
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				+                inComing: { 
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				+                    StreamID: connectionAttribute.inComing.StreamID, 
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				+                    PublisherID: connectionAttribute.inComing.PublisherID, 
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				+                    SubscriberID: connectionAttribute.inComing.SubscriberID, 
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				+                    serverUrl: connectionAttribute.inComing.serverUrl, 
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				+                    MessageToBePublished: null, 
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				+                    MessageToBeReceived: null 
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				+                }, 
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				+                connectionStatus: null 
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				+            } 
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				+            let call = client.HandleMessage({ id: connectionAttribute.inComing.serverUrl, message: JSON.stringify(localInfo) }) 
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				+ 
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				+            console.log(`Sending request to ${connectionAttribute.inComing.serverUrl} to open response channel...`) 
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				+ 
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				+            call.on('status', (status: Status) => { 
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				+                if (status == grpc.status.OK) { // only returns a status when there's error. Otherwise it just waits 
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				+                    console.log(`Message trasmission operation is successful`) 
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				+                    // RPC completed successfully 
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				+                } if (status == grpc.status.UNAVAILABLE) { 
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				+                    let report: ConnectionState = { 
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				+                        status: 'BUFFER', 
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				+                        reason: `Server doesn't seem to be alive. Error returned.`, 
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				+                        payload: this.messageToBeSendOver ?? `There's no message at the moment...` 
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				+                    } 
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				+                    connectionAttribute.connectionStatus!.next(report) 
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				+                    let clientStatusUpdateInfo: any = { 
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				+                        connectionStatus: 'OFF', 
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				+                        connectionID: connectionAttribute.ConnectionID.remote, 
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				+                        message: `${connectionAttribute.outGoing.serverUrl} started.` 
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				+                    } 
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				+                    this.clientRequest.next(clientStatusUpdateInfo) 
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				+                    resolve('No connection established. Server is not responding..') 
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				+                } 
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				+            }); 
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				+ 
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				+            call.on('data', (data: any) => { 
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				+                let response: Message = { 
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				+                    id: data.id, 
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				+                    message: JSON.parse(data.message) 
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				+                } 
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				+                if (connectionAttribute.inComing.MessageToBeReceived) { 
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				+                    connectionAttribute.inComing.MessageToBeReceived.next(response) 
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				+                } 
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				+            }); 
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				+ 
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				+            call.on('error', (err) => { 
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				+                console.error(err) 
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				+                resolve('') 
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				+            }); 
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				+        }) 
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				+    } 
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				+ 
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				+ 
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				+    // THis is no longer necesarry after the introduction of connection Attribute. But it is still useful for checking for the other side's health 
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				+    public async checkConnectionHealth(client: any, statusControl: Subject<ConnectionState>, alreadyHealthCheck: boolean): Promise<boolean> { 
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				+        return new Promise((resolve, reject) => { 
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				+            client.Check({}, (error, response) => { 
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				+                if (response) { 
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				+                    console.log(`GRPC Health check status: ${response.status} Server Connected`); 
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				+                    // Intepret the response status and implement code logic or handler 
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				+                    resolve(response.status) 
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				+                } else { 
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				+                    if (alreadyHealthCheck == false) console.error(`Health check failed: ${error}`); 
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				+                    reject(false) 
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				+                } 
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				+            }) 
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				+        }) 
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				+    } 
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				+ 
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				+    // TO check or validate if the client request meets the criteria 
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				+    private isConnectionAttribute(obj: any): obj is ConnectionAttribute { 
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				+        const isMatch = ( 
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				+            typeof obj.ConnectionID === 'object' && // Further checks can be added based on the structure of ConnectionID 
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				+            isStreamAttribute(obj.outGoing) && 
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				+            isStreamAttribute(obj.inComing) && 
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				+            (obj.connectionStatus === null || obj.connectionStatus instanceof Subject) 
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				+        ); 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+ 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+        if (isMatch) { 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+            console.log('gRPC client call matches ConnectionAttribute type'); 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+        } else { 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+            console.log('gRPC client call does not match ConnectionAttribute type'); 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+        } 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+ 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+        return isMatch; 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+        function isStreamAttribute(obj: any): obj is StreamAttribute { 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+            return ( 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+                (typeof obj.StreamID === 'string' || obj.StreamID === undefined) && 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+                (typeof obj.PublisherID === 'string' || obj.PublisherID === undefined) && 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+                (typeof obj.SubscriberID === 'string' || obj.SubscriberID === undefined) && 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+                // Check other properties like PublisherInstance and SubscriberInstance based on their expected types 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+                (typeof obj.serverUrl === 'string' || obj.serverUrl === undefined) && 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+                // Check connectionState based on its type, assuming it's an enum or similar 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+                (obj.MessageToBePublished === null || obj.MessageToBePublished instanceof Observable) && 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+                (obj.MessageToBeReceived === null || obj.MessageToBeReceived instanceof Subject) 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+            ); 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+        } 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    } 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+ 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    // update the referenced array  
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    // public updateConnectionStatus(connectionAttributeArray: ConnectionAttribute[]) { 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //     if (this.updateConnectionStatusFlag === false) { 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //         this.updateConnectionStatusFlag = true 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //         this.localServerStatus.subscribe({ 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //             next: (notification: any) => { 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //                 if (notification.connectionStatus === `ON`) { 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //                     let connectionAttribute = connectionAttributeArray.find(connection => connection.ConnectionID.local == notification.connectionID) 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //                     if (connectionAttribute) { 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //                         connectionAttribute.outGoing.connectionState = 'ON' 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //                         console.log(`Local Connection ${notification.connectionID} updated. {${connectionAttribute.outGoing.connectionState}}`) 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //                     } else { 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //                         console.log(`Local Connection ${notification.connectionID} attribute is not found.`) 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //                     } 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //                 } 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //             }, 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //             error: err => console.error(err), 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //             complete: () => { } 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //         }) 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //         this.clientRequest.subscribe({ 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //             next: (clientConnectionAttribute: ConnectionAttribute) => { 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //                 console.log(`Received a request from ${clientConnectionAttribute.outGoing.serverUrl}`) 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //                 let connectionAttribute = connectionAttributeArray.find(connection => connection.ConnectionID.remote == clientConnectionAttribute.ConnectionID.local) 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //                 if (connectionAttribute) { 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //                     connectionAttribute.inComing.connectionState = 'ON' 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //                     console.log(`Client Connection ${clientConnectionAttribute.ConnectionID.local} updated. {${connectionAttribute.inComing.connectionState}}`) 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //                 } else { 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //                     console.log(`Client Connection Attribute ${clientConnectionAttribute.inComing.PublisherID} is not found`) 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //                 } 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //             }, 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //             error: err => console.error(err), 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //             complete: () => { } 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //         }) 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //     } else { 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //         console.log(`Update Connection Status already called.`) 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    //     } 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+    // } 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+} 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+// https://github.com/grpc/proposal/blob/master/L5-node-client-interceptors.md 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+ 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+ 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+ 
			 | 
		
	
		
			
				 | 
				 | 
			
			
				+ 
			 |