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The KubeMQ SDK for NodeJS enables Node JS/Typescript developers to seamlessly communicate with the KubeMQ server, implementing various communication patterns such as Events, EventStore, Commands, Queries, and Queues.

Prerequisites

  • Node.js (Ensure you have a recent version of Node.js installed)

  • TypeScript Compiler

  • KubeMQ server running locally or accessible over the network

Installation

The recommended way to use the SDK for Node in your project is to consume it from Node package manager.


npm install kubemq-js

Payload Details

  • Metadata: The metadata allows us to pass additional information with the event. Can be in any form that can be presented as a string, i.e., struct, JSON, XML and many more.
  • Body: The actual content of the event. Can be in any form that is serializable into a byte array, i.e., string, struct, JSON, XML, Collection, binary file and many more.
  • ClientID: Displayed in logs, tracing, and KubeMQ dashboard(When using Events Store, it must be unique).
  • Tags: Set of Key-value pair that help categorize the message

KubeMQ PubSub Client

For executing PubSub operation we have to create the instance of PubsubClient, its instance can be created with minimum two parameter address (KubeMQ server address) & clientId . With these two parameter plainText connections are established. The table below describes the Parameters available for establishing a connection.

PubSub Client Configuration

Name Type Description Default Value Mandatory
address String The address of the KubeMQ server. None Yes
clientId String The client ID used for authentication. None Yes
authToken String The authorization token for secure communication. None No
tls boolean Indicates if TLS (Transport Layer Security) is enabled. None No
tlsCertFile String The path to the TLS certificate file. None No (Yes if tls is true)
tlsKeyFile String The path to the TLS key file. None No (Yes if tls is true)
tlsCaCertFile String The path to the TLS CA cert file. None No (Yes if tls is true)
maxReceiveSize int The maximum size of the messages to receive (in bytes). 104857600 (100MB) No
reconnectIntervalSeconds int The interval in seconds between reconnection attempts. 1 No

Pubsub Client connection establishment example code

const  opts: Config = {
	address:  'localhost:50000',
	clientId:  Utils.uuid(),
	reconnectIntervalSeconds:  1,
};

const  pubsubClient = new  PubsubClient(opts);

The example below demonstrates to construct PubSubClient with ssl and other configurations:

const  config: Config = {

	address:  'localhost:50000', // KubeMQ gRPC endpoint address
	clientId:  'your-client-id', // Connection clientId
	authToken:  'your-jwt-auth-token', // Optional JWT authorization token
	tls:  true, // Indicates if TLS is enabled
	tlsCertFile:  'path/to/tls-cert.pem', // Path to the TLS certificate file
	tlsKeyFile:  'path/to/tls-key.pem', // Path to the TLS key file
	tlsCaCertFile:  'path/to/tls-key.pem', // Path to the TLS key file
	maxReceiveSize:  1024 * 1024 * 100, // Maximum size of the messages to receive (100MB)
	reconnectIntervalSeconds:  1 // Interval in milliseconds between reconnect attempts (1 second)
};

Ping To KubeMQ server

You can ping the server to check connection is established or not.

Request: NONE

Response: ServerInfo Interface Attributes

Name Type Description
host String The host of the server.
version String The version of the server.
serverStartTime long The start time of the server (in seconds).
serverUpTimeSeconds long The uptime of the server (in seconds). 
ServerInfo  pingResult = pubsubClient.ping();
console.log('Ping Response: ' + pingResult);

Create Channel

PubSub CreateEventsChannel Example:

Request:

Name Type Description Default Value Mandatory
channelName String Channel name which you want to create None Yes

Response:

Name Type Description
void Promise Doesn't return a value upon completion 
async  function  createEventsChannel(channel: string) {
return  pubsubClient.createEventsChannel(channel);
}

PubSub Create Events Store Channel Example:

Request:

Name Type Description Default Value Mandatory
channelName String Channel name to which you want to create None Yes

Response:

Name Type Description
void Promise Doesn't return a value upon completion 
async  function  createEventsStoreChannel(channel: string) {
return  pubsubClient.createEventsStoreChannel(channel);
}

Delete Channel

PubSub DeleteEventsChannel Example:

Request:

Name Type Description Default Value Mandatory
channelName String Channel name which you want to delete None Yes

Response:

Name Type Description
void Promise Doesn't return a value upon completion 
async  function  deleteEventsChannel(channel: string) {
return  pubsubClient.deleteEventsChannel(channel);
}

PubSub Delete Events Store Channel Example:

Request:

Name Type Description Default Value Mandatory
channelName String Channel name to which you want to delete None Yes

Response:

Name Type Description
void Promise Doesn't return a value upon completion 
async  function  deleteEventsStoreChannel(channel: string) {
return  pubsubClient.deleteEventsStoreChannel(channel);
}

List Channels

PubSub ListEventsChannel Example:

Request:

Name Type Description Default Value Mandatory
search String Search query to filter channels (optional) None No

Response: PubSubChannel[] PubSubChannel interface Attributes

Name Type Description
name String The name of the Pub/Sub channel.
type String The type of the Pub/Sub channel.
lastActivity long The timestamp of the last activity on the channel, represented in milliseconds since epoch.
isActive boolean Indicates whether the channel is active or not.
incoming PubSubStats The statistics related to incoming messages for this channel.
outgoing PubSubStats The statistics related to outgoing messages for this channel. 
async  function  listEventsChannel(search: string) {
	const  channels = await  pubsubClient.listEventsChannels(search);
	console.log(channels);
}

PubSub ListEventsStoreChannel Example:

Request:

Name Type Description Default Value Mandatory
search String Search query to filter channels (optional) None No

Response: PubSubChannel[] PubSubChannel interface Attributes

Name Type Description
name String The name of the Pub/Sub channel.
type String The type of the Pub/Sub channel.
lastActivity long The timestamp of the last activity on the channel, represented in milliseconds since epoch.
isActive boolean Indicates whether the channel is active or not.
incoming PubSubStats The statistics related to incoming messages for this channel.
outgoing PubSubStats The statistics related to outgoing messages for this channel. 
async  function  listEventsStoreChannel(search: string) {
	const  channels = await  pubsubClient.listEventsStoreChannels(search);
	console.log(channels);
}

PubSub Send & Receive

PubSub SendEventMessage Example:

Request: EventMessage Interface Attributes

Name Type Description Default Value Mandatory
id String Unique identifier for the event message. None No
channel String The channel to which the event message is sent. None Yes
metadata String Metadata associated with the event message. None No
body byte[] Body of the event message in bytes. Empty byte array No
tags Map<String, String> Tags associated with the event message as key-value pairs. Empty Map No

Note:- metadata or body or tags any one is required

Response: NONE

await  pubsubClient.sendEventsMessage({
	id:  `234`,
	channel: 'events.single',
	body:  Utils.stringToBytes('event message'),
});

PubSub SendEventStoreMessage Example:

Request: EventStoreMessage Class Attributes

Name Type Description Default Value Mandatory
id String Unique identifier for the event message. None No
channel String The channel to which the event message is sent. None Yes
metadata String Metadata associated with the event message. None No
body byte[] Body of the event message in bytes. Empty byte array No
tags Map<String, String> Tags associated with the event message as key-value pairs. Empty Map No

Note:- metadata or body or tags any one is required

Response: NONE

await  pubsubClient.sendEventStoreMessage({
	id:  '987',
	channel: 'events_store.single',
	body:  Utils.stringToBytes('event store message'),
});

PubSub SubscribeEvents Example:

Request: EventsSubscription Class Attributes

Name Type Description Default Value Mandatory
channel String The channel to subscribe to. None Yes
group String The group to subscribe with. None No
onReceiveEventCallback Consumer Callback function to be called when an event message is received. None Yes
onErrorCallback Consumer Callback function to be called when an error occurs. None No

Response: NONE

Callback: EventMessageReceived class details

Name Type Description
id String The unique identifier of the message.
fromClientId String The ID of the client that sent the message.
timestamp long The timestamp when the message was received, in seconds.
channel String The channel to which the message belongs.
metadata String The metadata associated with the message.
body byte[] The body of the message.
sequence long The sequence number of the message.
tags Map<String, String> The tags associated with the message. 
async function subscribeToEvent() {  
  //Subscribes to events from the specified channel and processes received events.  
  const eventsSubscriptionRequest = new EventsSubscriptionRequest('events.A', '');  
  
  // Define the callback for receiving events  
  eventsSubscriptionRequest.onReceiveEventCallback = (event: EventMessageReceived) => {  
    console.log('SubscriberA received event:', {  
      id: event.id,  
      fromClientId: event.fromClientId,  
      timestamp: event.timestamp,  
      channel: event.channel,  
      metadata: event.metadata,  
      body: event.body,  
      tags: event.tags,  
    });  
  };  
  
  // Define the callback for handling errors  
  eventsSubscriptionRequest.onErrorCallback = (error: string) => {  
    console.error('SubscriberA error:', error);  
  };  
  
  pubsubClient  
  .subscribeToEvents(eventsSubscriptionRequest)  
    .then(() => {  
      console.log('Subscription successful');  
    })  
    .catch((reason: any) => {  
      console.error('Subscription failed:', reason);  
    });  
  
}

PubSub SubscribeEventsStore Example:

Request: EventsStoreSubscription Interface Attributes

Name Type Description Default Value Mandatory
channel String The channel to subscribe to. None Yes
group String The group to subscribe with. None No
onReceiveEventCallback Consumer Callback function to be called when an event message is received. None Yes
onErrorCallback Consumer Callback function to be called when an error occurs. None No

Response: None

Callback: EventStoreMessageReceived class details

Name Type Description
id String The unique identifier of the message.
fromClientId String The ID of the client that sent the message.
timestamp long The timestamp when the message was received, in seconds.
channel String The channel to which the message belongs.
metadata String The metadata associated with the message.
body byte[] The body of the message.
sequence long The sequence number of the message.
tags Map<String, String> The tags associated with the message. 
async function subscribeToEventStore() {  
  //Subscribes to events store messages from the specified channel with a specific configuration.  
  const eventsSubscriptionRequest = new EventsStoreSubscriptionRequest('events_store.A', '');  
  eventsSubscriptionRequest.eventsStoreType = EventStoreType.StartAtSequence;  
  eventsSubscriptionRequest.eventsStoreSequenceValue=1;  
  
  // Define the callback for receiving events  
  eventsSubscriptionRequest.onReceiveEventCallback = (event: EventStoreMessageReceived) => {  
    console.log('SubscriberA received event:', {  
      id: event.id,  
      fromClientId: event.fromClientId,  
      timestamp: event.timestamp,  
      channel: event.channel,  
      metadata: event.metadata,  
      body: event.body,  
      tags: event.tags,  
      sequence: event.sequence,  
    });  
  };  
  
  // Define the callback for handling errors  
  eventsSubscriptionRequest.onErrorCallback = (error: string) => {  
    console.error('SubscriberA error:', error);  
  };  
  
  pubsubClient  
  .subscribeToEvents(eventsSubscriptionRequest)  
    .then(() => {  
      console.log('Events Subscription successful');  
    })  
    .catch((reason: any) => {  
      console.error('Event Subscription failed:', reason);  
    });  
}

KubeMQ Queues Operations

The examples below demonstrate the usage of KubeMQ Queues client. The examples include creating, deleting, listing channels, and sending/receiving queues messages.

Construct the Queues Client

For executing Queues operation we have to create the instance of QueuesClient, its instance can be created with minimum two parameter address (KubeMQ server address) & clientId . With these two parameter plainText connections are established. The table below describes the Parameters available for establishing a connection.

QueuesClient Configuration

Name Type Description Default Value Mandatory
address String The address of the KubeMQ server. None Yes
clientId String The client ID used for authentication. None Yes
authToken String The authorization token for secure communication. None No
tls boolean Indicates if TLS (Transport Layer Security) is enabled. None No
tlsCertFile String The path to the TLS certificate file. None No (Yes if tls is true)
tlsKeyFile String The path to the TLS key file. None No (Yes if tls is true)
tlsCaCertFile String The path to the TLS CA cert file. None No (Yes if tls is true)
maxReceiveSize int The maximum size of the messages to receive (in bytes). 104857600 (100MB) No
reconnectIntervalSeconds int The interval in seconds between reconnection attempts. 1 No

Queues Client establishing a connection example code

const  opts: Config = {
	address:  'localhost:50000',
	clientId:  Utils.uuid(),
};

const  queuesClient = new  QueuesClient(opts);

The example below demonstrates to construct PubSubClient with ssl and other configurations:

const  opts: Config = {
	address:  'localhost:50000', // KubeMQ gRPC endpoint address
	clientId:  'your-client-id', // Connection clientId
	authToken:  'your-jwt-auth-token', // Optional JWT authorization token
	tls:  true, // Indicates if TLS is enabled
	tlsCertFile:  'path/to/tls-cert.pem', // Path to the TLS certificate file
	tlsKeyFile:  'path/to/tls-key.pem', // Path to the TLS key file
	tlsCaCertFile:  'path/to/tls-ca-cert.pem', // Path to the TLS CA cert file
	maxReceiveSize:  1024 * 1024 * 100, // The Maximum size of the messages to receive (100MB)
	reconnectIntervalSeconds:  1 // Interval in milliseconds between reconnect attempts (1 second)
};

const  queuesClient = new  QueuesClient(opts);

Ping To KubeMQ server

You can ping the server to check connection is established or not.

Request: NONE

Response: ServerInfo Class Attributes

Name Type Description
host String The host of the server.
version String The version of the server.
serverStartTime long The start time of the server (in seconds).
serverUpTimeSeconds long The uptime of the server (in seconds). 
const  pingResult = queuesClient.ping();
console.log('Ping Response: ' + pingResult);

Create Channel

Queues CreateQueueChannel Example:

Request:

Name Type Description Default Value Mandatory
channelName String The name of the channel you want to create None Yes

Response:

Name Type Description
void Promise Doesn't return a value upon completion 
async  function  createQueueChannel(channel: string) {
	return  queuesClient.createQueuesChannel(channel);
}

Delete Channel

Queues DeleteQueueChannel Example:

Request:

Name Type Description Default Value Mandatory
channelName String The name of the channel you want to delete None Yes

Response:

Name Type Description
void Promise Doesn't return a value upon completion 
async  function  createQueueChannel(channel: string) {
	return  queuesClient.deleteQueuesChannel(channel);
}

List Channels

Queues listQueueChannels Example:

Request:

Name Type Description Default Value Mandatory
searchString String The channel name you want to search for None No

Response: QueuesChannel[] QueuesChannel interface Attributes

Name Type Description
name String The name of the queue channel.
type String The type of the queue channel.
lastActivity long The timestamp of the last activity in the queue channel.
isActive boolean Indicates whether the queue channel is currently active.
incoming QueuesStats The statistics for incoming messages in the queue channel.
outgoing QueuesStats The statistics for outgoing messages in the queue channel. 
async  function  listQueueChannels(search: string) {
	const  channels = await  queuesClient.listQueuesChannel(search);
	console.log(channels);
}

Send & Receive Queue Messages

Queues SendSingleMessage Example:

Request: QueueMessage class attributes

Name Type Description Default Value Mandatory
id String The unique identifier for the message. None No
channel String The channel of the message. None Yes
metadata String The metadata associated with the message. None No
body byte[] The body of the message. new byte[0] No
tags Map<String, String> The tags associated with the message. new HashMap<>() No
delayInSeconds int The delay in seconds before the message becomes available in the queue. None No
expirationInSeconds int The expiration time in seconds for the message. None No
attemptsBeforeDeadLetterQueue int The number of receive attempts allowed before the message is moved to the dead letter queue. None No
deadLetterQueue String The dead letter queue where the message will be moved after reaching max receive attempts. None No

Response: QueueSendResult class attributes

Name Type Description
id String The unique identifier of the message.
sentAt LocalDateTime The timestamp when the message was sent.
expiredAt LocalDateTime The timestamp when the message will expire.
delayedTo LocalDateTime The timestamp when the message will be delivered.
isError boolean Indicates if there was an error while sending the message.
error String The error message if isError is true. 
await  queuesClient.sendQueuesMessage({
	channel:  'queues.single',
	body:  Utils.stringToBytes('queue message'),
})
.then((result) =>  console.log(result))
.catch((reason) =>  console.error(reason));

Queues Pulls messages from a queue. Example:

Request: QueuesPullWaitingMessagesRequest class attributes

Name Type Description Default Value Mandatory
channel String The channel to poll messages from. None Yes
maxNumberOfMessages int The maximum number of messages to poll. 1 No
waitTimeoutSeconds int The wait timeout in seconds for polling messages. 60 No

Response: QueuesPullWaitingMessagesResponse class attributes

Name Type Description
id String The reference ID of the request.
messagesReceived number Number of valid messages received.
messages QueueMessage[] The list of received queue messages.
error String The error message, if any error occurred.
isError boolean Indicates if there was an error.
isPeek boolean Indicates if it is a peek or pull operation.
messagesExpired number Number of expired messages from the queue. 
await  queuesClient
.pull({
	channel:  'queues.peek',
	maxNumberOfMessages:  10,
	waitTimeoutSeconds:  10,
})

.then((response) => {
	response.messages.forEach((msg) => {
	console.log(msg);
});
})

.catch((reason) => {
	console.error(reason);
});

Queues Get waiting messages from a queue Example:

Request: QueuesPullWaitngMessagesRequest class attributes

Name Type Description Default Value Mandatory
channel String The channel to poll messages from. None Yes
maxNumberOfMessages int The maximum number of messages to poll. 1 No
waitTimeoutSeconds int The wait timeout in seconds for polling messages. 60 No

Response: QueuesPullWaitingMessagesResponse class attributes

Name Type Description
id String The reference ID of the request.
messagesReceived number Number of valid messages received.
messages QueueMessage[] The list of received queue messages.
error String The error message, if any error occurred.
isError boolean Indicates if there was an error.
isPeek boolean Indicates if the operation is a peek or pull.
messagesExpired number Number of expired messages from the queue. 
await  queuesClient
.waiting({
	channel:  'queues.peek',
	maxNumberOfMessages:  5,
	waitTimeoutSeconds:  20,
})

.then((response) => {
	response.messages.forEach((msg) => {
	console.log(msg);
});
})
.catch((reason) => {
	console.error(reason);
});

Poll Queue Messages

Receives messages from a Queue channel.

Request: QueuesPollRequest Class Attributes

Name Type Description Default Value Mandatory
channel String The channel to poll messages from. None Yes
pollMaxMessages int The maximum number of messages to poll. 1 No
pollWaitTimeoutInSeconds int The wait timeout in seconds for polling messages. 60 No
autoAckMessages boolean Indicates if messages should be auto-acknowledged. false No
visibilitySeconds int Add a visibility timeout feature for messages. 0 No

Response: QueuesMessagesPulledResponse Class Attributes

Name Type Description
id String The reference ID of the request.
messages QueueMessageReceived[] The list of received queue messages.
messagesReceived number Number of valid messages received.
messagesExpired number Number of messages expired.
isPeek boolean Indicates if the operation is a peek or pull.
error String The error message, if any error occurred.
isError boolean Indicates if there was an error.
visibilitySeconds int The visibility timeout for the message in seconds.
isAutoAcked boolean Indicates whether the message was auto-acknowledged.

Response: QueueMessageReceived class attributes

Here's the requested Markdown table for the QueueMessageReceived class:

Name Type Description
id String The unique identifier for the message.
channel String The channel from which the message was received.
metadata String Metadata associated with the message.
body byte[] The body of the message in byte array format.
fromClientId String The ID of the client that sent the message.
tags Map<String, String> Key-value pairs representing tags for the message.
timestamp Instant The timestamp when the message was created.
sequence long The sequence number of the message.
receiveCount int The number of times the message has been received.
isReRouted boolean Indicates whether the message was rerouted.
reRouteFromQueue String The name of the queue from which the message was rerouted.
expiredAt Instant The expiration time of the message, if applicable.
delayedTo Instant The time the message is delayed until, if applicable.
transactionId String The transaction ID associated with the message.
isTransactionCompleted boolean Indicates whether the transaction for the message is completed.
responseHandler StreamObserver<QueuesDownstreamRequest> The response handler for processing downstream requests.
receiverClientId String The ID of the client receiving the message.
visibilitySeconds int The visibility timeout for the message in seconds.
isAutoAcked boolean Indicates whether the message was auto-acknowledged.

Example

async function main() {  
  const opts: Config = {  
    address: 'localhost:50000',  
    clientId: 'kubeMQClientId-ts',  
  };  
  const queuesClient = new QueuesClient(opts);  
  
  // Receive with message visibility  
  async function receiveWithVisibility(visibilitySeconds: number) {  
    console.log("\n============================== Receive with Visibility =============================\n");  
    try {  
      const pollRequest = new QueuesPollRequest({  
        channel: 'visibility_channel',  
        pollMaxMessages: 1,  
        pollWaitTimeoutInSeconds: 10,  
        visibilitySeconds: visibilitySeconds,  
        autoAckMessages: false,  
      });  
  
      const pollResponse = await queuesClient.receiveQueuesMessages(pollRequest);  
      console.log("Received Message Response:", pollResponse);  
        
      if (pollResponse.isError) {  
        console.log("Error: " + pollResponse.error);  
      } else {  
        pollResponse.messages.forEach(async (msg) => {  
          console.log(`Message ID: ${msg.id}, Message Body: ${Utils.bytesToString(msg.body)}`);  
          try {  
            await new Promise(resolve => setTimeout(resolve, 1000));  
            await msg.ack();  
            console.log("Acknowledged message");  
          } catch (err) {  
            console.error("Error acknowledging message:", err);  
          }  
        });  
      }  
    } catch (error) {  
      console.error('Failed to receive queue messages:', error);  
    }  
  }  
  
  // Test visibility expiration  
  async function receiveWithVisibilityExpired() {  
    console.log("\n============================== Receive with Visibility Expired =============================\n");  
    await receiveWithVisibility(2);  
  }  
  
  // Test visibility extension  
  async function receiveWithVisibilityExtension() {  
    console.log("\n============================== Receive with Visibility Extension =============================\n");  
    try {  
      const pollRequest = new QueuesPollRequest({  
        channel: 'visibility_channel',  
        pollMaxMessages: 1,  
        pollWaitTimeoutInSeconds: 10,  
        visibilitySeconds: 3,  
        autoAckMessages: false,  
      });  
  
      const pollResponse = await queuesClient.receiveQueuesMessages(pollRequest);  
      console.log("Received Message Response:", pollResponse);  
  
      if (pollResponse.isError) {  
        console.log("Error: " + pollResponse.error);  
      } else {  
        pollResponse.messages.forEach(async (msg) => {  
          console.log(`Message ID: ${msg.id}, Message Body: ${Utils.bytesToString(msg.body)}`);  
          try {  
            await new Promise(resolve => setTimeout(resolve, 1000));  
            await msg.extendVisibilityTimer(3);  
            await new Promise(resolve => setTimeout(resolve, 2000));  
            await msg.ack();  
            console.log("Acknowledged message after extending visibility");  
          } catch (err) {  
            console.error("Error during visibility extension:", err);  
          }  
        });  
      }  
    } catch (error) {  
      console.error('Failed to receive queue messages:', error);  
    }  
  }  
  
  await receiveWithVisibilityExpired();  
  await receiveWithVisibilityExtension();  
}  
  
main();

This method allows you to receive messages from a specified Queue channel. You can configure the polling behavior, including the maximum number of messages to receive and the wait timeout. The response provides detailed information about the received messages and the transaction.

Message Handling Options:

  1. Acknowledge (ack): Mark the message as processed and remove it from the queue.
  2. Reject: Reject the message. It won't be requeued.
  3. Requeue: Send the message back to the queue for later processing.

Choose the appropriate handling option based on your application's logic and requirements.

KubeMQ Command & Query Operations

Construct the CQClient

For executing command & query operation we have to create the instance of CQClient, its instance can be created with minimum two parameter address (KubeMQ server address) & clientId . With these two parameter plainText connections are established. The table below describes the Parameters available for establishing a connection.

CQClient Configuration

Name Type Description Default Value Mandatory
address String The address of the KubeMQ server. None Yes
clientId String The client ID used for authentication. None Yes
authToken String The authorization token for secure communication. None No
tls boolean Indicates if TLS (Transport Layer Security) is enabled. None No
tlsCertFile String The path to the TLS certificate file. None No (Yes if tls is true)
tlsKeyFile String The path to the TLS key file. None No (Yes if tls is true)
tlsCaCertFile String The path to the TLS CA cert file. None No (Yes if tls is true)
maxReceiveSize int The maximum size of the messages to receive (in bytes). 104857600 (100MB) No
reconnectIntervalSeconds int The interval in seconds between reconnection attempts. 1 No

CQClient establishing a connection example code

const  opts: Config = {

    address:  'localhost:50000',
    clientId:  Utils.uuid(),
    reconnectIntervalSeconds:  1,
};

const  cqClient = new  CQClient(opts);

The example below demonstrates to construct CQClient with ssl and other configurations:

const  config: Config = {

    address:  'localhost:50000', // KubeMQ gRPC endpoint address
    clientId:  'your-client-id', // Connection clientId
    authToken:  'your-jwt-auth-token', // Optional JWT authorization token
    tls:  true, // Indicates if TLS is enabled
    tlsCertFile:  'path/to/tls-cert.pem', // Path to the TLS certificate file
    tlsKeyFile:  'path/to/tls-key.pem', // Path to the TLS key file
    tlsCaCertFile:  'path/to/tls-ca-cert.pem', // Path to the TLS CA cert file
    maxReceiveSize:  1024 * 1024 * 100, // Maximum size of the messages to receive (100MB)
    reconnectIntervalSeconds:  1, // Interval in milliseconds between reconnect attempts (1 second)
};
const  cqClient = new  CQClient(opts);

Ping To KubeMQ server

You can ping the server to check connection is established or not.

Request: NONE

Response: ServerInfo interface Attributes

Name Type Description
host String The host of the server.
version String The version of the server.
serverStartTime long The start time of the server (in seconds).
serverUpTimeSeconds long The uptime of the server (in seconds). 
const  pingResult = cqClient.ping();
console.log('Ping Response: ' + pingResult);

Create Channel

Command CreateCommandsChannel Example:

Request:

Name Type Description Default Value Mandatory
channelName String Channel name which you want to create None Yes

Response:

Name Type Description
void Promise Doesn't return a value upon completion 
async  function  createCommandsChannel(channel: string) {
    return  cqClient.createCommandsChannel(channel);
}

Queries CreateQueriesChannel Example:

Request:

Name Type Description Default Value Mandatory
channelName String The name of the channel to create. None Yes

Response:

Name Type Description
void Promise Doesn't return a value upon completion 
async  function  createQueriesChannel(channel: string) {
    return  cqClient.createQueriesChannel(channel);
}

Delete Channel

Command DeleteCommandsChannel Example:

Request:

Name Type Description Default Value Mandatory
channelName String Channel name which you want to delete None Yes

Response:

Name Type Description
void Promise Doesn't return a value upon completion 
async  function  deleteCommandsChannel(channel: string) {
    return  cqClient.deleteCommandsChannel(channel);
}

Queries DeleteQueriesChannel Example:

Request:

Name Type Description Default Value Mandatory
channelName String The name of the channel to delete None Yes

Response:

Name Type Description
void Promise Doesn't return a value upon completion 
async  function  deleteQueriesChannel(channel: string) {
    return  cqClient.deleteQueriesChannel(channel);
}

List Channels

Command ListCommandsChannel Example:

Request:

Name Type Description Default Value Mandatory
searchString String The name of the channel to search for. None No

Response: CQChannel[] CQChannel interface attributes

Name Type Description
name String The name of the channel.
type String The type of the channel.
lastActivity long The timestamp of the last activity on the channel.
isActive boolean Indicates whether the channel is currently active.
incoming CQStats Statistics about incoming messages to the channel.
outgoing CQStats Statistics about outgoing messages from the channel. 
async  function  listCommandsChannels(search: string) {
    const  channels = await  cqClient.listCommandsChannels(search);
    console.log(channels);
}

Queries ListQueriesChannel Example:

Request:

Name Type Description Default Value Mandatory
searchString String Channel name which you want to search None No

Response: List<CQChannel> CQChannel class attributes

Name Type Description
name String The name of the channel.
type String The type of the channel.
lastActivity long The timestamp of the last activity on the channel.
isActive boolean Indicates whether the channel is currently active.
incoming CQStats Statistics about incoming messages to the channel.
outgoing CQStats Statistics about outgoing messages from the channel. 
async  function  listQueriesChannels(search: string) {
    const  channels = await  cqClient.listQueriesChannels(search);
    console.log(channels);
}

Send & Receive Command & Query Messages

Command SubscribeToCommandsChannel Example:

Request: CommandsSubscription Class Attributes

Name Type Description Default Value Mandatory
channel String The channel for the subscription. None Yes
group String The group associated with the subscription. None No
onReceiveCommandCallback CommandsReceiveMessage Callback function for receiving commands. None Yes

Response: None

Callback: CommandsReceiveMessage interface attributes

Name Type Description
commandReceived CommandsReceiveMessage The command message that was received.
clientId String The ID of the client that sent the command.
requestId String The ID of the request.
isExecuted boolean Indicates whether the command was executed.
timestamp LocalDateTime The timestamp of the response.
error String The error message if an error occurred. 
async function subscribeToCommands(channelName: string) {
    //Subscribes to commands from the specified channel with a specific configuration.  
    const commandSubscriptionRequest = new CommandsSubscriptionRequest(channelName, 'group1');

    // Define the callback for receiving commandMessage  
    commandSubscriptionRequest.onReceiveEventCallback = (commandMessage: CommandMessageReceived) => {
        console.log('SubscriberA received commandMessage:', {
            id: commandMessage.id,
            fromClientId: commandMessage.fromClientId,
            timestamp: commandMessage.timestamp,
            channel: commandMessage.channel,
            metadata: commandMessage.metadata,
            body: commandMessage.body,
            tags: commandMessage.tags,
        });
    };

    // Define the callback for handling errors  
    commandSubscriptionRequest.onErrorCallback = (error: string) => {
        console.error('SubscriberA error:', error);
    };

    cqClient.subscribeToCommands(commandSubscriptionRequest)
        .then(() => {
            console.log('Command Subscription successful');
        })
        .catch((reason: any) => {
            console.error('Command Subscription failed:', reason);
        });
}

Queries SubscribeToQueriesChannel Example:

Request: QueriesSubscriptionRequest Class Attributes

Name Type Description Default Value Mandatory
channel String The channel for the subscription. None Yes
group String The group associated with the subscription. None No
onReceiveQueriesCallback QueriesReceiveMessage Callback function for receiving queries. None Yes

Response: None

Callback: QueriesReceiveMessage interface attributes

Name Type Description
id String The ID of the request.
channel String Channel name from which the message was received.
metadata String Metadata of the message.
body Uint8Array The body of the response.
tags Map<String, String> Tags associated with the query message.
replyChannel String The reply channel for this message. 
async function subscribeToQueries(channelName: string) {

    //Subscribes to queries from the specified channel with a specific configuration.  
    const commandSubscriptionRequest = new CommandsSubscriptionRequest(channelName, 'group1');

    // Define the callback for receiving queriesMessage  
    commandSubscriptionRequest.onReceiveEventCallback = (commandMessage: CommandMessageReceived) => {
        console.log('SubscriberA received event:', {
            id: commandMessage.id,
            fromClientId: commandMessage.fromClientId,
            timestamp: commandMessage.timestamp,
            channel: commandMessage.channel,
            metadata: commandMessage.metadata,
            body: commandMessage.body,
            tags: commandMessage.tags,
        });
    };

    // Define the callback for handling errors  
    commandSubscriptionRequest.onErrorCallback = (error: string) => {
        console.error('SubscriberA error:', error);
    };

    cqClient.subscribeToQueries(commandSubscriptionRequest)
        .then(() => {
            console.log('Queries Subscription successful');
        })
        .catch((reason: any) => {
            console.error('Queries Subscription failed:', reason);
        });
}