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Get started with Azure Service Bus queues (JavaScript)
This tutorial shows you how to send messages to and receive messages from Azure Service Bus queues using the JavaScript programming language.
spelluru
spelluru
12/08/2023
quickstart
javascript
devx-track-js, mode-api

Send messages to and receive messages from Azure Service Bus queues (JavaScript)

[!div class="op_single_selector" title1="Select the programming language:"]

In this tutorial, you complete the following steps:

  1. Create a Service Bus namespace, using the Azure portal.
  2. Create a Service Bus queue, using the Azure portal.
  3. Write a JavaScript application to use the @azure/service-bus package to:
    1. Send a set of messages to the queue.
    2. Receive those messages from the queue.

Note

This quick start provides step-by-step instructions for a simple scenario of sending messages to a Service Bus queue and receiving them. You can find pre-built JavaScript and TypeScript samples for Azure Service Bus in the Azure SDK for JavaScript repository on GitHub.

Prerequisites

If you're new to the service, see Service Bus overview before you do this quickstart.

Passwordless

To use this quickstart with your own Azure account, you need:

  • Install Azure CLI, which provides the passwordless authentication to your developer machine.
  • Sign in with your Azure account at the terminal or command prompt with az login.
  • Use the same account when you add the appropriate data role to your resource.
  • Run the code in the same terminal or command prompt.
  • Note down your queue name for your Service Bus namespace. You'll need that in the code.

Connection string

Note down the following, which you'll use in the code below:

  • Service Bus namespace connection string
  • Service Bus namespace queue you created

Note

This tutorial works with samples that you can copy and run using Nodejs. For instructions on how to create a Node.js application, see Create and deploy a Node.js application to an Azure Website, or Node.js cloud service using Windows PowerShell.

[!INCLUDE service-bus-create-namespace-portal]

[!INCLUDE service-bus-create-queue-portal]

[!INCLUDE service-bus-passwordless-template-tabbed]

Use Node Package Manager (NPM) to install the package

Passwordless

  1. To install the required npm package(s) for Service Bus, open a command prompt that has npm in its path, change the directory to the folder where you want to have your samples and then run this command.

  2. Install the following packages:

    npm install @azure/service-bus @azure/identity

Connection string

  1. To install the required npm package(s) for Service Bus, open a command prompt that has npm in its path, change the directory to the folder where you want to have your samples and then run this command.

  2. Install the following package:

    npm install @azure/service-bus

Send messages to a queue

The following sample code shows you how to send a message to a queue.

Passwordless

You must have signed in with the Azure CLI's az login in order for your local machine to provide the passwordless authentication required in this code.

  1. Open your favorite editor, such as Visual Studio Code.

  2. Create a file called send.js and paste the below code into it. This code sends the names of scientists as messages to your queue.

    [!IMPORTANT] The passwordless credential is provided with the DefaultAzureCredential.

    const { ServiceBusClient } = require("@azure/service-bus");
const { DefaultAzureCredential } = require("@azure/identity");

// Replace `<SERVICE-BUS-NAMESPACE>` with your namespace
const fullyQualifiedNamespace = "<SERVICE-BUS-NAMESPACE>.servicebus.windows.net";

// Passwordless credential
const credential = new DefaultAzureCredential();

// name of the queue
const queueName = "<QUEUE NAME>"

const messages = [
    { body: "Albert Einstein" },
    { body: "Werner Heisenberg" },
    { body: "Marie Curie" },
    { body: "Steven Hawking" },
    { body: "Isaac Newton" },
    { body: "Niels Bohr" },
    { body: "Michael Faraday" },
    { body: "Galileo Galilei" },
    { body: "Johannes Kepler" },
    { body: "Nikolaus Kopernikus" }
    ];

async function main() {
    // create a Service Bus client using the passwordless authentication to the Service Bus namespace
    const sbClient = new ServiceBusClient(fullyQualifiedNamespace, credential);

    // createSender() can also be used to create a sender for a topic.
    const sender = sbClient.createSender(queueName);

    try {
        // Tries to send all messages in a single batch.
        // Will fail if the messages cannot fit in a batch.
        // await sender.sendMessages(messages);

        // create a batch object
        let batch = await sender.createMessageBatch();
        for (let i = 0; i < messages.length; i++) {
            // for each message in the array

            // try to add the message to the batch
            if (!batch.tryAddMessage(messages[i])) {
                // if it fails to add the message to the current batch
                // send the current batch as it is full
                await sender.sendMessages(batch);

                // then, create a new batch
                batch = await sender.createMessageBatch();

                // now, add the message failed to be added to the previous batch to this batch
                if (!batch.tryAddMessage(messages[i])) {
                    // if it still can't be added to the batch, the message is probably too big to fit in a batch
                    throw new Error("Message too big to fit in a batch");
                }
            }
        }

        // Send the last created batch of messages to the queue
        await sender.sendMessages(batch);

        console.log(`Sent a batch of messages to the queue: ${queueName}`);

        // Close the sender
        await sender.close();
    } finally {
        await sbClient.close();
    }
}

// call the main function
main().catch((err) => {
    console.log("Error occurred: ", err);
    process.exit(1);
    });

  3. Replace <SERVICE-BUS-NAMESPACE> with your Service Bus namespace.

  4. Replace <QUEUE NAME> with the name of the queue.

  5. Then run the command in a command prompt to execute this file.

    node send.js

  6. You should see the following output.

    Sent a batch of messages to the queue: myqueue

Connection string

  1. Open your favorite editor, such as Visual Studio Code.

  2. Create a file called send.js and paste the below code into it. This code sends the names of scientists as messages to your queue.

    const { ServiceBusClient } = require("@azure/service-bus");

// connection string to your Service Bus namespace
const connectionString = "<CONNECTION STRING TO SERVICE BUS NAMESPACE>"

// name of the queue
const queueName = "<QUEUE NAME>"

const messages = [
    { body: "Albert Einstein" },
    { body: "Werner Heisenberg" },
    { body: "Marie Curie" },
    { body: "Steven Hawking" },
    { body: "Isaac Newton" },
    { body: "Niels Bohr" },
    { body: "Michael Faraday" },
    { body: "Galileo Galilei" },
    { body: "Johannes Kepler" },
    { body: "Nikolaus Kopernikus" }
 ];

async function main() {
    // create a Service Bus client using the connection string to the Service Bus namespace
    const sbClient = new ServiceBusClient(connectionString);

    // createSender() can also be used to create a sender for a topic.
    const sender = sbClient.createSender(queueName);

    try {
        // Tries to send all messages in a single batch.
        // Will fail if the messages cannot fit in a batch.
        // await sender.sendMessages(messages);

        // create a batch object
        let batch = await sender.createMessageBatch();
        for (let i = 0; i < messages.length; i++) {
            // for each message in the array

            // try to add the message to the batch
            if (!batch.tryAddMessage(messages[i])) {
                // if it fails to add the message to the current batch
                // send the current batch as it is full
                await sender.sendMessages(batch);

                // then, create a new batch
                batch = await sender.createMessageBatch();

                // now, add the message failed to be added to the previous batch to this batch
                if (!batch.tryAddMessage(messages[i])) {
                    // if it still can't be added to the batch, the message is probably too big to fit in a batch
                    throw new Error("Message too big to fit in a batch");
                }
            }
        }

        // Send the last created batch of messages to the queue
        await sender.sendMessages(batch);

        console.log(`Sent a batch of messages to the queue: ${queueName}`);

        // Close the sender
        await sender.close();
    } finally {
        await sbClient.close();
    }
}

// call the main function
main().catch((err) => {
    console.log("Error occurred: ", err);
    process.exit(1);
 });

  3. Replace <CONNECTION STRING TO SERVICE BUS NAMESPACE> with the connection string to your Service Bus namespace.

  4. Replace <QUEUE NAME> with the name of the queue.

  5. Then run the command in a command prompt to execute this file.

    node send.js

  6. You should see the following output.

    Sent a batch of messages to the queue: myqueue

Receive messages from a queue

Passwordless

You must have signed in with the Azure CLI's az login in order for your local machine to provide the passwordless authentication required in this code.

  1. Open your favorite editor, such as Visual Studio Code

  2. Create a file called receive.js and paste the following code into it.

    const { delay, ServiceBusClient, ServiceBusMessage } = require("@azure/service-bus");
const { DefaultAzureCredential } = require("@azure/identity");

// Replace `<SERVICE-BUS-NAMESPACE>` with your namespace
const fullyQualifiedNamespace = "<SERVICE-BUS-NAMESPACE>.servicebus.windows.net";

// Passwordless credential
const credential = new DefaultAzureCredential();

// name of the queue
const queueName = "<QUEUE NAME>"

 async function main() {
    // create a Service Bus client using the passwordless authentication to the Service Bus namespace
    const sbClient = new ServiceBusClient(fullyQualifiedNamespace, credential);

    // createReceiver() can also be used to create a receiver for a subscription.
    const receiver = sbClient.createReceiver(queueName);

    // function to handle messages
    const myMessageHandler = async (messageReceived) => {
        console.log(`Received message: ${messageReceived.body}`);
    };

    // function to handle any errors
    const myErrorHandler = async (error) => {
        console.log(error);
    };

    // subscribe and specify the message and error handlers
    receiver.subscribe({
        processMessage: myMessageHandler,
        processError: myErrorHandler
    });

    // Waiting long enough before closing the sender to send messages
    await delay(20000);

    await receiver.close();
    await sbClient.close();
}
// call the main function
main().catch((err) => {
    console.log("Error occurred: ", err);
    process.exit(1);
 });

  3. Replace <SERVICE-BUS-NAMESPACE> with your Service Bus namespace.

  4. Replace <QUEUE NAME> with the name of the queue.

  5. Then run the command in a command prompt to execute this file.

    node receive.js

Connection string

  1. Open your favorite editor, such as Visual Studio Code

  2. Create a file called receive.js and paste the following code into it.

    const { delay, ServiceBusClient, ServiceBusMessage } = require("@azure/service-bus");

// connection string to your Service Bus namespace
const connectionString = "<CONNECTION STRING TO SERVICE BUS NAMESPACE>"

// name of the queue
const queueName = "<QUEUE NAME>"

 async function main() {
    // create a Service Bus client using the connection string to the Service Bus namespace
    const sbClient = new ServiceBusClient(connectionString);

    // createReceiver() can also be used to create a receiver for a subscription.
    const receiver = sbClient.createReceiver(queueName);

    // function to handle messages
    const myMessageHandler = async (messageReceived) => {
        console.log(`Received message: ${messageReceived.body}`);
    };

    // function to handle any errors
    const myErrorHandler = async (error) => {
        console.log(error);
    };

    // subscribe and specify the message and error handlers
    receiver.subscribe({
        processMessage: myMessageHandler,
        processError: myErrorHandler
    });

    // Waiting long enough before closing the sender to send messages
    await delay(20000);

    await receiver.close();
    await sbClient.close();
}
// call the main function
main().catch((err) => {
    console.log("Error occurred: ", err);
    process.exit(1);
 });

  3. Replace <CONNECTION STRING TO SERVICE BUS NAMESPACE> with the connection string to your Service Bus namespace.

  4. Replace <QUEUE NAME> with the name of the queue.

  5. Then run the command in a command prompt to execute this file.

    node receive.js

You should see the following output.

Received message: Albert Einstein
Received message: Werner Heisenberg
Received message: Marie Curie
Received message: Steven Hawking
Received message: Isaac Newton
Received message: Niels Bohr
Received message: Michael Faraday
Received message: Galileo Galilei
Received message: Johannes Kepler
Received message: Nikolaus Kopernikus

On the Overview page for the Service Bus namespace in the Azure portal, you can see incoming and outgoing message count. You may need to wait for a minute or so and then refresh the page to see the latest values.

:::image type="content" source="./media/service-bus-java-how-to-use-queues/overview-incoming-outgoing-messages.png" alt-text="Incoming and outgoing message count":::

Select the queue on this Overview page to navigate to the Service Bus Queue page. You see the incoming and outgoing message count on this page too. You also see other information such as the current size of the queue, maximum size, active message count, and so on.

:::image type="content" source="./media/service-bus-java-how-to-use-queues/queue-details.png" alt-text="Queue details":::

Troubleshooting

If you receive one of the following errors when running the passwordless version of the JavaScript code, make sure you are signed in via the Azure CLI command, az login and the appropriate role is applied to your Azure user account:

  • 'Send' claim(s) are required to perform this operation
  • 'Receive' claim(s) are required to perform this operation

Clean up resources

Navigate to your Service Bus namespace in the Azure portal, and select Delete on the Azure portal to delete the namespace and the queue in it.

Next steps

See the following documentation and samples: