Kafka topics

The CLI can view, create and modify topics.

View all topics

The optional names flag wil display only the names of the topics. If you use the –unwrap flag, each topic name will be displayed on a new line as text:

lenses-cli topics [--names [--unwrap]]

View a specific topic

lenses-cli topic --name=reddit_posts

Create topics

lenses-cli topic create \
    --name="topicName" \
    --replication=1 \
    --partitions=1 \
    --configs="{\"max.message.bytes\": \"1000010\"}"

Update from a file:

lenses-cli topic create ./topic.yml

Example file:

name: topicName
replication: 1
partitions: 1
configs:
  max.message.bytes: "1000010"

Update a topic’s configuration

lenses-cli topic update \
    --name="topic2" \
    --configs="{\"max.message.bytes\": \"1000020\"}"

Update from a file:

lenses-cli topic update ./topic.yaml

Example file:

name: topicName
replication: 1
partitions: 1
configs:
  max.message.bytes: "1000010"

Update a topic’s metadata configuration

# first change the key/value type
lenses-cli topics metadata set \
    --name=topicName \
    --key-type=bytes \
    --value-type=xml

# now you may change its schema
lenses-cli topics metadata set \
    --name=topicName \
    --key-type=bytes \
    --key-schema="{\"type\":\"record\",\"name\":\"lenses_record\",\"namespace\":\"lenses\",\"fields\":[{\"name\":\"keyField\",\"type\":\"string\"}]}" \
    --value-type=xml \
    --value-schema="{\"type\":\"record\",\"name\":\"lenses_record\",\"namespace\":\"lenses\",\"fields\":[{\"name\":\"valueField\",\"type\":\"string\"}]}"

Update from a file:

lenses-cli topic update ./topic.yaml

Example file:

topicName: topicName
keyType: bytes
valueType: xml
valueSchema: "{\"type\":\"record\",\"name\":\"lenses_record\",\"namespace\":\"lenses\",\"fields\":[{\"name\":\"heading3\",\"type\":\"string\"}]}"

Delete topics

lenses-cli topic delete --name="topic2"

Last modified: May 29, 2023