Kafka¶

Steps for interacting with Apache Kafka message broker

Multi-line Content

Steps ending with : accept multi-line content using Gherkin's docstring syntax ("""). See examples below each section.

Topic Management¶

Step	Description
`"{resource}" topic "events" exists`	Asserts a Kafka topic exists
`"{resource}" creates topic "events"`	Creates a Kafka topic with 1 partition
`"{resource}" creates topic "events" with "3" partitions`	Creates a Kafka topic with specified partitions

Publishing¶

Step	Description
`"{resource}" message header "trace-id" is "abc-123"`	Sets a header on the next message published (any publish step)
`"{resource}" publishes to "events":`	Publishes a message to a topic
`"{resource}" publishes to "events" with key "user-123":`	Publishes a message with a key to a topic
`"{resource}" publishes json to "events":`	Publishes a JSON message to a topic
`"{resource}" publishes json to "events" with key "user-123":`	Publishes a JSON message with a key
`"{resource}" publishes messages to "events":`	Publishes multiple messages from a table

Examples¶

Publishes a message to a topic:

"{resource}" publishes to "events":
  """
  Hello World
  """

Publishes a message with a key to a topic:

"{resource}" publishes to "events" with key "user-123":
  """
  Hello World
  """

Publishes a JSON message to a topic:

"{resource}" publishes json to "events":
  """
  {"type": "user_created"}
  """

Publishes a JSON message with a key:

"{resource}" publishes json to "events" with key "user-123":
  """
  {"type": "user_created"}
  """

Publishes multiple messages from a table:

"{resource}" publishes messages to "events":
  | key      | value           |
  | user-1   | {"id": 1}     |

Avro and Schema Registry¶

Step	Description
`"{resource}" registers schema for subject "orders-value":`	Registers an Avro schema under a subject
`"{resource}" registers schema for subject "orders-value" from file "schemas/order.avsc"`	Registers an Avro schema (.avsc) from a file
`"{resource}" publishes avro to "orders":`	Publishes JSON as Avro, using the latest schema of the topic's value subject
`"{resource}" publishes avro to "orders" with key "order-1":`	Publishes JSON as Avro with a string key
`"{resource}" receives avro from "orders" within "10s":`	Waits for an Avro message whose JSON form contains the given fields
`"{resource}" last message avro matches:`	Asserts the last message, decoded from Avro, equals the JSON exactly
`"{resource}" last message avro contains:`	Asserts the last message, decoded from Avro, contains the JSON fields

Examples¶

Registers an Avro schema under a subject:

"{resource}" registers schema for subject "orders-value":
  """
  {"type": "record", "name": "Order", "fields": [{"name": "id", "type": "string"}]}
  """

Publishes JSON as Avro, using the latest schema of the topic's value subject:

"{resource}" publishes avro to "orders":
  """
  {"id": "order-1"}
  """

Publishes JSON as Avro with a string key:

"{resource}" publishes avro to "orders" with key "order-1":
  """
  {"id": "order-1"}
  """

Waits for an Avro message whose JSON form contains the given fields:

"{resource}" receives avro from "orders" within "10s":
  """
  {"id": "order-1"}
  """

Asserts the last message, decoded from Avro, equals the JSON exactly:

"{resource}" last message avro matches:
  """
  {"id": "order-1", "note": null}
  """

Asserts the last message, decoded from Avro, contains the JSON fields:

"{resource}" last message avro contains:
  """
  {"id": "order-1"}
  """

Consuming¶

Step	Description
`"{resource}" consumes from "events"`	Starts consuming messages from a topic
`"{resource}" receives from "events" within "5s"`	Waits for a message from a topic within timeout
`"{resource}" receives from "events" within "5s":`	Asserts a specific message is received within timeout
`"{resource}" receives from "events" with key "user-123" within "5s"`	Asserts a message with specific key is received

Examples¶

Asserts a specific message is received within timeout:

"{resource}" receives from "events" within "5s":
  """
  Hello World
  """

Assertions¶

Step	Description
`"{resource}" topic "events" has "3" messages`	Asserts topic has exactly N messages consumed
`"{resource}" topic "events" is empty`	Asserts no messages have been consumed from topic
`"{resource}" last message contains:`	Asserts the last consumed message contains content
`"{resource}" last message has key "user-123"`	Asserts the last consumed message has specific key
`"{resource}" last message has header "content-type" with value "application/json"`	Asserts the last message has a header with value
`"{resource}" receives messages from "events" in order:`	Asserts messages are received in specified order

Examples¶

Asserts the last consumed message contains content:

"{resource}" last message contains:
  """
  user_created
  """

Asserts messages are received in specified order:

"{resource}" receives messages from "events" in order:
  | key    | value  |
  | key1   | msg1   |

Consumer Groups¶

Step	Description
`"{resource}" consumes from "events" as consumer group "billing"`	Joins a consumer group on a topic; its messages are received like any other
`"{resource}" consumer group "billing" is consuming "events" within "30s"`	Waits until a member of the consumer group is assigned the topic, as the broker sees it
`"{resource}" consumer group "billing" has no members`	Asserts the consumer group has no members, as the broker sees it