## providers.mongokafka.PersistentKafkaPublisher

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A Kafka event publisher that uses a MongoDB DAO to store stateless events as-is.


Usage

``` python
providers.mongokafka.PersistentKafkaPublisher(
    *, event_publisher, dao, compacted_topics, topics_not_stored
)
```


This class should be used for events that do not represent a stateful object, such as user info, but rather stateless information. This includes things like notifications, completed actions, file processing results, etc.


## Methods

| Name | Description |
|----|----|
| [__init__()](#__init__) | Please do not call directly! Should be called by the [construct](providers.mongodb.MongoDbDaoFactory.md#hexkit.providers.mongodb.MongoDbDaoFactory.construct) method. |
| [construct()](#construct) | Setup and teardown KafkaEventPublisher instance with some config params. |
| [publish_pending()](#publish_pending) | Publishes all non-published events. |
| [republish()](#republish) | Republishes all stored events independent of whether they have |

<span id="__init__"></span>

<span id="hexkit.providers.mongokafka.PersistentKafkaPublisher.__init__"></span>


#### \_\_init\_\_()


Please do not call directly! Should be called by the [construct](providers.mongodb.MongoDbDaoFactory.md#hexkit.providers.mongodb.MongoDbDaoFactory.construct) method.


Usage

``` python
__init__(*, event_publisher, dao, compacted_topics, topics_not_stored)
```


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------------------------------------------------------------------------


#### construct()


Setup and teardown KafkaEventPublisher instance with some config params.


Usage

``` python
construct(
    *,
    config,
    dao_factory,
    compacted_topics=None,
    topics_not_stored=None,
    collection_name="",
    kafka_producer_cls=AIOKafkaProducer
)
```


##### Parameters


`config: MongoKafkaConfig`  
Config parameters needed for connecting to Apache Kafka.

`compacted_topics: set[str] | None = None`  
A set of topics that should be compacted. For these topics, only the latest event for a given key will be republished. Prior events for a given key in a compacted topic are replaced by new events, so only one event should be stored at a given time per key per topic.

`topics_not_stored: set[str] | None = None`  
A set of topics which should not be stored in the database. Events for these topics will be published identically as they would be in the [KafkaEventPublisher](providers.akafka.KafkaEventPublisher.md#hexkit.providers.akafka.KafkaEventPublisher) class.

`collection_name: str = ``""`  
The name of the MongoDB collection in which to store events.

`dao_factory: MongoDbDaoFactory`  
A MongoDbDaoFactory instance that can be used to create a DAO.

`kafka_producer_cls: type[KafkaProducerCompatible] = AIOKafkaProducer`  
Overwrite the used Kafka Producer class. Only intended for unit testing.


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------------------------------------------------------------------------


#### publish_pending()


Publishes all non-published events.


Usage

``` python
publish_pending()
```


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------------------------------------------------------------------------


#### republish()


Republishes all stored events independent of whether they have


Usage

``` python
republish()
```


already been published or not.