Connector configuration in Kafka - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to set the connector name.

Kafka

{
  "name": "[1]",
  "config": {
    "connector.class": "FileStreamSource"
  }
}

Drag options to blanks, or click blank then click option'

Asource-connector

Bfile-connector

Cconnector1

Dmy-connector

Attempts:

3 left

💡 Hint

Common Mistakes

Leaving the name field empty or missing quotes.

Using invalid characters in the connector name.

The name field sets the unique name of the connector. Here, connector1 is used as the connector name.

2fill in blank

medium

Complete the code to specify the connector class.

Kafka

{
  "name": "source-connector",
  "config": {
    "connector.class": "[1]",
    "tasks.max": "1"
  }
}

Drag options to blanks, or click blank then click option'

AFileStreamSink

BFileStreamSource

CJdbcSourceConnector

DKafkaSinkConnector

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing source and sink connector classes.

Using a class name that does not exist.

The connector.class specifies the Java class that implements the connector. FileStreamSource is the correct class for reading from a file source.

3fill in blank

hard

Fix the error in the configuration by completing the missing topic name.

Kafka

{
  "name": "file-source-connector",
  "config": {
    "connector.class": "FileStreamSource",
    "tasks.max": "1",
    "file": "/tmp/test.txt",
    "topic": "[1]"
  }
}

Drag options to blanks, or click blank then click option'

Atest-topic

Bfile-topic

Csource-topic

Dinput-topic

Attempts:

3 left

💡 Hint

Common Mistakes

Leaving the topic name empty or misspelled.

Using a topic name that does not exist in Kafka.

The topic field specifies the Kafka topic where data will be sent. test-topic is the expected topic name here.

4fill in blank

hard

Fill both blanks to configure the maximum tasks and the file path.

Kafka

{
  "name": "file-source-connector",
  "config": {
    "connector.class": "FileStreamSource",
    "tasks.max": "[1]",
    "file": "[2]",
    "topic": "test-topic"
  }
}

Drag options to blanks, or click blank then click option'

A1

B/var/log/input.log

C/tmp/data.txt

D3

Attempts:

3 left

💡 Hint

Common Mistakes

Setting tasks.max to a non-numeric value.

Using an invalid file path.

tasks.max controls how many tasks run in parallel; here it is set to 1. The file path specifies the input file; /tmp/data.txt is used here.

5fill in blank

hard

Fill all three blanks to complete the connector configuration with name, class, and topic.

Kafka

{
  "name": "[1]",
  "config": {
    "connector.class": "[2]",
    "tasks.max": "1",
    "file": "/tmp/input.txt",
    "topic": "[3]"
  }
}

Drag options to blanks, or click blank then click option'

Afile-source-connector

BFileStreamSource

Cinput-topic

Dsource-connector

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up the connector class with the topic name.

Using inconsistent names across fields.

The name is set to file-source-connector, the connector.class is FileStreamSource, and the topic is input-topic. This completes the connector configuration.

Practice

1. What is the main purpose of a connector configuration in Kafka Connect?

easy

A. To specify how data moves between Kafka and external systems

B. To define the Kafka broker's internal settings

C. To configure Kafka topic partitions

D. To set the Kafka consumer group ID

Solution

1. Step 1: Understand Kafka Connect role

   Kafka Connect uses connectors to move data between Kafka and other systems.

2. Step 2: Identify configuration purpose

   The connector configuration tells Kafka Connect how to perform this data movement.

3. Final Answer:

   To specify how data moves between Kafka and external systems -> Option A

4. Quick Check:

   Connector configuration = data movement setup [OK]

Hint: Connector config defines data flow direction [OK]

Common Mistakes:

• Confusing connector config with Kafka broker settings
• Thinking it configures Kafka topic partitions
• Mixing up consumer group ID with connector config

2. Which of the following is the correct way to specify the connector class in a Kafka Connect configuration JSON?

easy

A. "connectorClassName": "org.apache.kafka.connect.file.FileStreamSourceConnector"

B. "connector.class": "org.apache.kafka.connect.file.FileStreamSourceConnector"

C. "connectorClass": "org.apache.kafka.connect.file.FileStreamSourceConnector"

D. "connector-class": "org.apache.kafka.connect.file.FileStreamSourceConnector"

Solution

1. Step 1: Recall Kafka Connect JSON key format

   Kafka Connect uses keys with dot notation, e.g., "connector.class".

2. Step 2: Match correct key name

   Only "connector.class": "org.apache.kafka.connect.file.FileStreamSourceConnector" uses the correct key "connector.class" with quotes and colon.

3. Final Answer:

   "connector.class": "org.apache.kafka.connect.file.FileStreamSourceConnector" -> Option B

4. Quick Check:

   Correct key is "connector.class" [OK]

Hint: Use dot notation keys like "connector.class" [OK]

Common Mistakes:

• Using hyphens instead of dots in keys
• Using camelCase keys instead of dot notation
• Omitting quotes around keys or values

3. Given this connector configuration snippet:

{
  "name": "my-source-connector",
  "connector.class": "org.apache.kafka.connect.file.FileStreamSourceConnector",
  "tasks.max": "2",
  "file": "/tmp/input.txt",
  "topic": "my-topic"
}

What does the tasks.max setting control?

medium

A. Maximum number of Kafka topics to consume

B. Maximum number of retries for failed tasks

C. Maximum size of each task's data batch

D. Maximum number of tasks to run in parallel for this connector

Solution

1. Step 1: Understand tasks.max meaning

   In Kafka Connect, tasks.max sets how many parallel tasks the connector can run.

2. Step 2: Eliminate other options

   It does not control topic count, batch size, or retry count.

3. Final Answer:

   Maximum number of tasks to run in parallel for this connector -> Option D

4. Quick Check:

   tasks.max = parallel task limit [OK]

Hint: tasks.max limits parallel connector tasks [OK]

Common Mistakes:

• Confusing tasks.max with topic count
• Thinking it controls batch size
• Assuming it sets retry attempts

4. You have this connector config JSON:

{
  "name": "my-sink-connector",
  "connector.class": "org.apache.kafka.connect.file.FileStreamSinkConnector",
  "tasks.max": 1,
  "topics": "my-topic"
}

What is wrong with this configuration?

medium

A. "connector.class" value is incorrect for a sink connector

B. "topics" key should be "topic" (singular)

C. Missing "file" property to specify output file

D. "tasks.max" should be a string, not a number

Solution

1. Step 1: Check required properties for FileStreamSinkConnector

   This connector needs a "file" property to specify the output file path.

2. Step 2: Validate other properties

   "tasks.max" can be a number or string, "topics" is valid plural, and "connector.class" is correct.

3. Final Answer:

   Missing "file" property to specify output file -> Option C

4. Quick Check:

   FileStreamSinkConnector requires "file" property [OK]

Hint: FileStreamSinkConnector needs "file" path set [OK]

Common Mistakes:

• Assuming "tasks.max" must be string
• Confusing "topic" and "topics" keys
• Changing connector.class unnecessarily

5. You want to configure a Kafka Connect source connector to read from a database table and write to a Kafka topic. Which configuration property is essential to specify the Kafka topic where data will be published?

hard

A. "topic"

B. "topics"

C. "topics.regex"

D. "kafka.topic"

Solution

1. Step 1: Understand topic properties in connectors

   Source connectors typically use "topic" (singular) to specify the Kafka topic to publish data to.

2. Step 2: Differentiate from other keys

   "topics" is common for sink connectors; "topics.regex" is for pattern matching; "kafka.topic" is not standard.

3. Final Answer:

   "topic" -> Option A

4. Quick Check:

   Use "topic" to specify Kafka topic for sources [OK]

Hint: Use "topic" for source connector Kafka topic [OK]

Common Mistakes:

• Using plural "topics" instead of "topic"
• Confusing "topics.regex" with direct topic specification
• Inventing non-standard keys like "kafka.topic"