Examples of working with a topic via the SQS API

This article provides examples of working with topics using the SQS API with the AWS CLI.

Before running the examples, configure access to the SQS API (in the Open Source version, disable the authentication requirement, see the section on authentication).

If you use AWS CLI, make sure it does not require configured AWS credentials: either add --no-sign-request to the commands, or set any values for AWS_ACCESS_KEY_ID/AWS_SECRET_ACCESS_KEY.

Forming the endpoint for connection

The endpoint for accessing the SQS API is formed as follows:

https://{db-balancer}:{port}/{database}

Where:

• db-balancer: DNS name of the HTTPS load balancer with database compute nodes as its backend (or the address of the node or service where the HTTP Proxy is running).
• port: port on which the HTTP Proxy is available.
• database: full path of the database that contains the topics.

This endpoint is specified in the AWS CLI via the --endpoint parameter.

Creating a topic

To create a topic, run the command:

ENDPOINT="https://my_db.balancer.example.com:8443/Root/my_db"

aws --endpoint "$ENDPOINT" \
  sqs create-queue --queue-name "my_topic"

After running the command, a topic with the specified name and a shared (common) reader named ydb-sqs-consumer will be created. You can check that the topic exists using the scheme describe command of the YDB CLI:

ydb -e grpcs://my_db.balancer.example.com:2135 -d /Root/my_db scheme describe my_topic

To create a FIFO queue, use the FifoQueue=true attribute. For FIFO queues, it is recommended to end the name with .fifo to comply with the Amazon SQS naming convention:

ENDPOINT="https://my_db.balancer.example.com:8443/Root/my_db"

aws --endpoint "$ENDPOINT" \
  sqs create-queue \
  --queue-name "my_topic.fifo" \
  --attributes FifoQueue=true

After running the command, a topic named my_topic.fifo and a shared (common) reader named ydb-sqs-consumer will be created, with message ordering enabled.

Getting a list of topics

To get a list of topics that can be accessed via the SQS protocol, run the command:

ENDPOINT="https://my_db.balancer.example.com:8443/Root/my_db"

aws --endpoint "$ENDPOINT" sqs list-queues

Writing to and reading from a topic

For read and write operations, the AWS CLI uses the --queue-url parameter. You can obtain it via get-queue-url.

Below is an example:

• Getting QueueUrl.
• Writing a message.
• Reading a message.

ENDPOINT="https://my_db.balancer.example.com:8443/Root/my_db"

# get QueueUrl
QUEUE_URL="$(aws --endpoint "$ENDPOINT" sqs get-queue-url --queue-name "my_topic" --query 'QueueUrl' --output text)"

# write a message to the topic
aws --endpoint "$ENDPOINT" sqs send-message \
  --queue-url "$QUEUE_URL" \
  --message-body "hello from aws cli"

# read a message (long polling)
aws --endpoint "$ENDPOINT" sqs receive-message \
  --queue-url "$QUEUE_URL" \
  --wait-time-seconds 20 \
  --max-number-of-messages 1