Exporting via a Kafka Consumer

Data can be consumed from your streams (both encrypted and decrypted events) in JSON format via an authorized and authenticated connection to our Kafka export cluster.

Create an exporter

First you need to create an exporter. This creates a Kafka Exporter and one associated Kafka User. The user credentials can be used to access the topic.

$ strm create kafka-exporter demo -o json
{
  "ref": {
    "name": "kafka-exporter-a9e83206-96e6-463c-8163-3f4493b3ddb7",
    "projectId": "30fcd008-9696-...."
  },
  "streamRef": {
    "name": "demo",
    "projectId": "30fcd008-9696-...."
  },
  "target": {
    "clusterRef": {
      "billingId": "internal",
      "name": "shared-export"
    },
    "topic": "export-a9e83206-96e6-463c-8163-3f4493b3ddb7"
  },
  "users": [
    {
      "ref": {
        "name": "service-account-export-7d36ea89-2c91-4959-a6bf-9af35a0c5ddb",
        "projectId": "30fcd008-9696-...."
      },
      "kafkaExporterName": "kafka-exporter-a9e83206-96e6-...",
      "topic": "export-a9e83206-96e6-...",
      "clientId": "export-7d36ea89-2c91-...",
      "clientSecret": "22a837fb-c299-...",
      "clusterRef": {
        "billingId": "internal",
        "name": "shared-export"
      }
    }
  ]
}

You can see the created user credentials. The Kafka Exporter is named shared-export-demo. shared-export is the name of the Kafka cluster owned by STRM Privacy that we export to; your Kafka consumer will consume from this cluster.

Kafka users are entities that can consume from the Kafka Export Cluster. They have credentials, and a Kafka topic that they can consume from.

$ strm list kafka-users shared-export-demo -o json
{
  "kafkaUsers": [
    {
      "ref": {
        "name": "service-account-export-7d36ea89-2c91-4959-a6bf-9af35a0c5ddb"
        "projectId": "30fcd008-9696-...."
      },
      "kafkaExporterName": "shared-export-demo",
      "topic": "export-a9e83206-96e6-463c-8163-3f4493b3ddb7",
      "clientId": "export-7d36ea89-2c91-4959-a6bf-9af35a0c5ddb",
      "clientSecret": "22a837fb-c299-4e03-b1ec-460684f52ae5",
      "clusterRef": {
        "billingId": "internal",
        "name": "shared-export"
      }
    }
  ]
}

Consuming

Clone the Python Kafka Consumer and go into the directory and create a file config.ini. Fill out the values from the JSON above:

config.ini

[kafka]
bootstrap_servers = export-bootstrap.kafka.strmprivacy.io:9092
topic = export-a9e83206-96e6-...
client_id = export-7d36ea89-2c91-...
secret = 22a837fb-c299-...
token_uri = https://sts.strmprivacy.io/token
group = demo

note

The group can have any arbitrary value. It acts as the group.id attribute in Kafka.

Next, install the Python dependencies:

python3 -m venv .venv
. .venv/bin/activate
python3 -m pip install -r requirements.txt

Generate some data in a separate terminal:

$ strm simulate random-events demo

And run the consumer:

$ python consumer.py

{'strmMeta': {
  'eventContractRef': 'strmprivacy/example/1.3.0',
  'nonce': -1508205704,
  'timestamp': 1629197150029,
  'keyLink': '68a1d5c5-d1d0-4a7c-8e03-b9d265071839',
  'billingId': None,
  'consentLevels': [0, 1]},
'uniqueIdentifier': 'ARCc26TVzQnf6SVZpFT3ghde/6ILaeFdn+o9jBW/',
'consistentValue': 'ARCc26QnGW52Po3QHjADcpvSoY6zf9z9skqy8viZwX8=',
'someSensitiveValue': 'ARCc26QwShhyvLiHj2EDEp7vSB0CxLMhOm7jAv0D4CM=',
'notSensitiveValue': 'not-sensitive-98'
}

Deleting the Kafka-Exporter

If you just try to delete the Kafka Exporter, you’ll get an error.

strm delete kafka-exporter shared-export-demo
Error: rpc error: code = FailedPrecondition desc = Cannot delete billing_id: "demo8542234275"
name: "shared-export-demo"
.name because it has users attached to it

First, the users have to be deleted:

strm delete kafka-user service-account-export-7d36ea89-2c91-4959-a6bf-9af35a0c5ddb
{"name":"service-account-export-7d36ea89-2c91-4959-a6bf-9af35a0c5ddb", "projectId": "30fcd008-9696-...."}

And then delete the Kafka Exporter with the same command as before.

A recursive delete would ensure that all attached resources are deleted in on command:

strm delete kafka-exporter shared-export-demo --recursive