`msight_core.topics`

Topic registry helpers.

This module defines a Topic with helpers to register and retrieve topic metadata from Redis. Topics basic information is stored as JSON strings in the hash key identified by :data:REDIS_TOPICS_FIELD and follow a small schema:

name: topic name (string)
description: optional textual description
data_type: fully-qualified import path for the data class

The :class:Topic object provides convenience methods to serialize to/from this dict schema and to register the topic in Redis. Use :meth:get_topic to load topic metadata from Redis and optionally register a new topic when it does not exist.

`Topic`

The Topic holds the topic name, a human-friendly description and the data type (a subclass of :class:~msight_core.data.Data). The :meth:to_dict / :meth:from_dict pair provide a stable JSON-serializable representation used for storage in Redis.

`to_dict()`

Return a JSON-serializable mapping for this topic.

Returns:

Name	Type	Description
`dict`	`dict`	Contains keys `name`, `description` and `data_type`. `data_type` is the fully-qualified import path for the data class (e.g. `msight_core.data.ImageData`).

`register()`

Register (or update) this topic in Redis.

The topic is stored in the hash named by :data:REDIS_TOPICS_FIELD. If the topic already exists the value will be overwritten.

`from_dict(d)` `staticmethod`

Create a :class:Topic from a deserialized mapping.

Parameters:

Name	Type	Description	Default
`d`	`dict`	Mapping with keys `name`, `data_type` and optional `description`.	required

Returns:

Name	Type	Description
`Topic`	`Topic`	Constructed Topic instance with the resolved data_type.

`get_topic(redis_client, topic_name, register_if_not_exist=False, data_type=None, description=None)`

Lookup a Topic by name in Redis and optionally register it.

Parameters:

Name	Type	Description	Default
`redis_client`	`Redis`	Redis client instance (supports `hget`/`hset`/`hexists`).	required
`topic_name`	`str`	Name of the topic to retrieve.	required
`register_if_not_exist`	`bool`	If True and the topic is missing, a new topic will be created using the provided `data_type` and `description` and stored in Redis.	`False`
`data_type`	`Optional[Type[Data]]`	Class object to use when registering a new topic (required when `register_if_not_exist` is True).	`None`
`description`	`str`	Optional description used when registering.	`None`

Returns:

Type	Description
`Topic`	Topic or None: The Topic instance when found or created; otherwise
`Topic`	`None` if the topic does not exist and `register_if_not_exist` is
`Topic`	False.

msight_core.topics