Delivering data from an Apache Kafka® queue to MongoDB

Written by

Yandex Cloud

Updated at September 24, 2024

Getting started
Prepare the test data
Prepare and activate the transfer
Test the transfer
Delete the resources you created

A Managed Service for MongoDB cluster can get data from Apache Kafka® topics in real time.

To run data delivery:

If you no longer need the resources you created, delete them.

Getting started

Prepare the data transfer infrastructure:
Manually

Terraform
1. Create a Managed Service for Apache Kafka® source cluster with any suitable configuration. To connect to the cluster from the user's local machine rather than doing so from the Yandex Cloud cloud network, enable public access to the cluster when creating it.
2. In the source cluster, create a topic named sensors.
3. In the source cluster, create a user named mkf-user with the ACCESS_ROLE_PRODUCER and ACCESS_ROLE_CONSUMER permissions for the created topic.
4. Create a Managed Service for MongoDB target cluster in any suitable configuration with the following settings:
  - Database name: db1.
  - Username: mmg-user.
  - In the same availability zone as the source cluster.
  - To connect to the cluster from the user's local machine instead of the Yandex Cloud cloud network, enable public access to the cluster hosts.
5. To connect to the cluster from the user's local machine, configure security groups:
  - Managed Service for Apache Kafka®.
  - Managed Service for MongoDB.
1. If you do not have Terraform yet, install it.
2. Get the authentication credentials. You can add them to environment variables or specify them later in the provider configuration file.
3. Configure and initialize a provider. There is no need to create a provider configuration file manually, you can download it.
4. Place the configuration file in a separate working directory and specify the parameter values. If you did not add the authentication credentials to environment variables, specify them in the configuration file.
5. Download the data-transfer-mkf-mmg.tf configuration file to the same working directory.
  
  This file describes:
  - Network.
  - Subnet.
  - Security group and rules required to connect to the Managed Service for Apache Kafka® and Managed Service for MongoDB clusters.
  - Managed Service for Apache Kafka® source cluster.
  - Apache Kafka® topic named sensors.
  - Apache Kafka® user named mkf-user with the ACCESS_ROLE_PRODUCER and ACCESS_ROLE_CONSUMER permissions to the sensors topic.
  - Managed Service for MongoDB target cluster.
  - MongoDB database named db1.
  - MongoDB user named mmg-user with the readWrite permissions to access the db1 database.
  - Transfer.
6. In the data-transfer-mkf-mmg.tf file, specify the variables:
  - source_kf_version: Apache Kafka® version in the source cluster.
  - source_user_password: Password of mkf-user in the source cluster.
  - target_mg_version: MongoDB version in the target cluster.
  - target_user_password: Password of mmg-user in the target cluster.
  - transfer_enabled: Set to 0 to ensure that no transfer is created until you create endpoints manually.
7. Make sure the Terraform configuration files are correct using this command:
  terraform validate
  If there are any errors in the configuration files, Terraform will point them out.
8. Create the required infrastructure:
  1. Run the command to view planned changes:
    
    terraform plan
    
    If the resource configuration descriptions are correct, the terminal will display a list of the resources to modify and their parameters. This is a test step. No resources are updated.
  2. If you are happy with the planned changes, apply them:
    
    Run the command:
    
    terraform apply
    
    Confirm the update of resources.
    
    Wait for the operation to complete.
  All the required resources will be created in the specified folder. You can check resource availability and their settings in the management console.
Install the utilities:
- kafkacat to read and write data to Apache Kafka® topics.
```
sudo apt update && sudo apt install --yes kafkacat
```
  Check that you can use it to connect to the Managed Service for Apache Kafka® source cluster over SSL.
- jq for JSON file stream processing.
```
sudo apt update && sudo apt-get install --yes jq
```

Prepare the test data

Let's assume the Apache Kafka® sensors topic in the source cluster receives data from car sensors in JSON format.

Create a local sample.json file with the following test data:

sample.json

{
    "device_id": "iv9a94th6rzt********",
    "datetime": "2020-06-05 17:27:00",
    "latitude": 55.70329032,
    "longitude": 37.65472196,
    "altitude": 427.5,
    "speed": 0,
    "battery_voltage": 23.5,
    "cabin_temperature": 17,
    "fuel_level": null
}
{
    "device_id": "rhibbh3y08qm********",
    "datetime": "2020-06-06 09:49:54",
    "latitude": 55.71294467,
    "longitude": 37.66542005,
    "altitude": 429.13,
    "speed": 55.5,
    "battery_voltage": null,
    "cabin_temperature": 18,
    "fuel_level": 32
}
{
    "device_id": "iv9a94th6rzt********",
    "datetime": "2020-06-07 15:00:10",
    "latitude": 55.70985913,
    "longitude": 37.62141918,
    "altitude": 417.0,
    "speed": 15.7,
    "battery_voltage": 10.3,
    "cabin_temperature": 17,
    "fuel_level": null
}

Prepare and activate the transfer

Create an endpoint for the Apache Kafka® source:

Endpoint parameters:

Connection settings:
- Connection type: Managed Service for Apache Kafka cluster.
  - Managed Service for Apache Kafka cluster: Select the source cluster from the list.
  - Authentication: SASL.
    - Username: mkf-user.
    - Password: Enter the user password.
- Topic full name: sensors.

Advanced settings → Conversion rules:

Conversion rules: JSON.

Data scheme: JSON specification.

Insert the data schema in JSON format:

json

[
    {
        "name": "device_id",
        "type": "utf8",
        "key": true
    },
    {
        "name": "datetime",
        "type": "utf8"
    },
    {
        "name": "latitude",
        "type": "double"
    },
    {
        "name": "longitude",
        "type": "double"
    },
    {
        "name": "altitude",
        "type": "double"
    },
    {
        "name": "speed",
        "type": "double"
    },
    {
        "name": "battery_voltage",
        "type": "double"
    },
    {
        "name": "cabin_temperature",
        "type": "uint16"
    },
    {
        "name": "fuel_level",
        "type": "uint16"
    }
]

Create an endpoint for the MongoDB target:

Endpoint parameters:
- Connection settings:
  - Connection type: Managed Service for MongoDB cluster.
    - Managed Service for MongoDB cluster: Select the source cluster from the list.
  - Authentication source: db1.
  - User: mmg-user.
  - Password: Enter the user password.
- Database: db1.
Create a transfer:
Manually

Terraform
1. Create a transfer of the Replication type that will use the created endpoints.
2. Activate the transfer and wait for its status to change to Replicating.
1. In the data-transfer-mkf-mmg.tf file, specify the variables:
  - source_endpoint_id: ID of the source endpoint.
  - target_endpoint_id: ID of the target endpoint.
  - transfer_enabled: Set to 1 to enable transfer creation.
2. Make sure the Terraform configuration files are correct using this command:
  terraform validate
  If there are any errors in the configuration files, Terraform will point them out.
3. Create the required infrastructure:
  1. Run the command to view planned changes:
    
    terraform plan
    
    If the resource configuration descriptions are correct, the terminal will display a list of the resources to modify and their parameters. This is a test step. No resources are updated.
  2. If you are happy with the planned changes, apply them:
    
    Run the command:
    
    terraform apply
    
    Confirm the update of resources.
    
    Wait for the operation to complete.
4. The transfer will be activated automatically. Wait for its status to change to Replicating.

Test the transfer

Make sure the data from the topic in the source Managed Service for Apache Kafka® cluster is being moved to the Managed Service for MongoDB cluster:

Send data from the sample.json file to the Managed Service for Apache Kafka® sensors topic using jq and kafkacat:

jq -rc . sample.json | kafkacat -P \
   -b <broker_host_FQDN>:9091 \
   -t sensors \
   -k key \
   -X security.protocol=SASL_SSL \
   -X sasl.mechanisms=SCRAM-SHA-512 \
   -X sasl.username="mkf-user" \
   -X sasl.password="<user_password_in_the_source_cluster>" \
   -X ssl.ca.location=/usr/local/share/ca-certificates/Yandex/YandexInternalRootCA.crt -Z

To learn more about setting up an SSL certificate and working with kafkacat, see Connecting to an Apache Kafka® cluster from applications.

Check that the sensors collection in the Managed Service for MongoDB cluster contains the sent data:
1. Connect to the Managed Service for MongoDB cluster.
2. Get the contents of the sensors collection using the query below:
```
db.sensors.find()
```

Delete the resources you created

Note

Before deleting the created resources, deactivate the transfer.

Some resources are not free of charge. To avoid paying for them, delete the resources you no longer need:

Delete the transfer.
Delete endpoints for both the source and target.

Delete the other resources depending on how they were created:

Manually

Terraform

In the terminal window, go to the directory containing the infrastructure plan.
Delete the data-transfer-mkf-mmg.tf configuration file.
Make sure the Terraform configuration files are correct using this command:
```
terraform validate
```
If there are any errors in the configuration files, Terraform will point them out.
Confirm updating the resources.
1. Run the command to view planned changes:
```
terraform plan
```
  If the resource configuration descriptions are correct, the terminal will display a list of the resources to modify and their parameters. This is a test step. No resources are updated.
2. If you are happy with the planned changes, apply them:
  1. Run the command:
```
terraform apply
```
  2. Confirm the update of resources.
  3. Wait for the operation to complete.
All the resources described in the data-transfer-mkf-mmg.tf configuration file will be deleted.

Delivering data from an Apache Kafka® queue to MongoDB

Getting startedGetting started

Prepare the test dataPrepare the test data

Prepare and activate the transferPrepare and activate the transfer

Test the transferTest the transfer

Delete the resources you createdDelete the resources you created

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Getting started

Prepare the test data

Prepare and activate the transfer

Test the transfer

Delete the resources you created