Correct way to process batches using receiveMessages

We are using the @azure/service-bus package to process message batches from multiple topics.

The code we use to take 20 messages from the topic every 2 seconds looks like this.

       let isProcessing: boolean = false;

       setInterval(async () => {

        if (isProcessing === false) {

            isProcessing = true;

            try {

                const messages: Array<ServiceBusMessage>
                    = await receiver.receiveMessages(Configuration.SB.batchSize as number);

                if (messages.length > 0) {

                    this.logger.info(`[SB] ${topic} - ${messages.length} require processing`);

                    await Promise.all([
                        ...messages.map(message => this.handleMsg(receiver, message, topic, moduleRef, handler))
                    ]).catch(error => {
                        this.logger.error(error.message, error);
                    });

                }

                isProcessing = false;

            } catch (error) {

                this.logger.error(error.message, error);

                isProcessing = false;

            }

        }

    }, Configuration.SB.tickInterval as number);

My question is - Is this the best way to do this? Is there a better way? It works and is fairly performant BUT I think we are losing receiveAndDelete messages sometimes and I am trying to workout if its our implementation

Thanks for any help

It works and is fairly performant BUT I think we are losing receiveAndDelete messages sometimes and I am trying to workout if its our implementation

There are two modes to receive messages

• Unsafe with ReceiveAndDelete
• Safe with PeekLock

When ReceiveAndDelete mode is used, the moment messages are received by the client, they are automatically deleted from the server. So this is at-most-once delivery.

With PeekLock a message is "leased" to the client for a maximum of 5 minutes and the client has to either acknowledge successful processing by requesting message completion or by cancelling/dead-lettering if it can't handle it. If none of these operations take place within the defined lease time (which doesn't have to be strictly 5 minutes and could be less), the message is retried until a maximum number of delivery attempts (MaxDeliveryCount) is exceeded and the message is dead-lettered. Note that the message is never lost. Even if it failed to process and was dead-lettered. Therefore this is at-least-once-delivery which could be more suitable for your scenario. It will have a slight impact on how you code your client, but not a drastic change.