Contracts reference

This page lists every contract in src/cluster_erp/core/contracts.py: the frozen dataclasses that modules exchange through the EventBus. For each contract it gives the kind, the line, the modules that construct it, and the modules that handle it. How the bus delivers contracts is explained on event bus; field lists are in the source file.

Scope and source¶

• Defined in: src/cluster_erp/core/contracts.py
• Count: 270 classes decorated with @dataclass(frozen=True (counted with grep -c "@dataclass(frozen=True"). Of these, 149 derive from Event (145 directly and 4 through _SubscriptionEvent), 118 derive from Query, and 3 are plain value types used inside DescribeAnalyticsFacts answers.
• 153 contracts have at least one handler. 117 have none. 38 have no producer found.

The columns were produced as follows:

• Kind: the base class on the class line.
• Line: the line of the class statement in src/cluster_erp/core/contracts.py.
• Producers: the modules whose files contain a call Name( (a construction) in src/cluster_erp/modules, src/cluster_erp/server, src/cluster_erp/core, or src/cluster_erp/ai, excluding contracts.py. core and server name those folders. "(by name)" marks the subscription events, which src/cluster_erp/modules/subscriptions/customer_subscriptions/services.py:423-429 builds through getattr on the contracts module.
• Consumers: the modules that pass the contract as the first argument of subscribe( or register_query_handler(, on the same line or the next line.
• - means that nothing was found by that method.

Groups follow the section comments of contracts.py. A group name is the section where the class is declared, not necessarily the module that publishes it; the Producers column shows the real producer.

Party domain¶

Organisation domain¶

Product and service domain¶

Auth domain¶

Document domain¶

Email domain¶

CRM domain¶

Quotation domain¶

Sales order domain¶

Project domain¶

Design and engineering domain¶

BOM domain¶

Inventory domain¶

Production domain¶

Nesting domain¶

Costing domain¶

Component allocation¶

Procurement domain¶

Working calendar domain¶

Analytics domain¶

Intranet domain¶

Subscriptions¶

Data-subject requests¶

Contracts after the last section comment¶

The contracts below follow the data-subject section in the file and carry no section comment of their own.

Constraints and validation¶

• Every contract is a frozen dataclass. Event and Query are declared frozen=True, kw_only=True, so every field is passed by keyword (src/cluster_erp/core/event_bus.py:24-32).
• Every contract carries source_module and timestamp from Event (src/cluster_erp/core/event_bus.py:25-27).
• A query type may have only one handler; registering a second raises DuplicateQueryHandlerError (src/cluster_erp/core/event_bus.py:73-79).
• GetInfoRecordPrice is a query with no producer and no handler found (src/cluster_erp/core/contracts.py:619). Calling bus.query with it would raise QueryHandlerNotFoundError (src/cluster_erp/core/event_bus.py:98-101).
• Contracts with no handler are delivered to nobody when emitted (src/cluster_erp/core/event_bus.py:85-87). Whether each of the 117 is reserved for future use is not determined from code.

Terms introduced¶

Related pages¶

• Platform core
• Event bus
• Module lifecycle
• Analytics facts

Verified against commit 92f8051 on 2026-11-13.