Implementation:Apache Paimon CatalogEnvironment

Knowledge Sources	Apache_Paimon
Domains	Catalog Management, Version Control
Last Updated	2026-02-08 00:00 GMT

Overview

CatalogEnvironment encapsulates catalog context including table identifier, UUID, catalog loader, and version management capabilities for snapshot commit operations.

Description

The CatalogEnvironment class provides a context object that carries essential catalog metadata and capabilities needed for table operations. It contains an optional Identifier for the table, a UUID for tracking, a CatalogLoader for accessing the catalog, and a flag indicating whether the catalog supports version management features.

The primary purpose of CatalogEnvironment is to determine the appropriate snapshot commit strategy. When version management is supported and a catalog loader is available, it creates a CatalogSnapshotCommit that uses catalog-level versioning APIs. Otherwise, it falls back to RenamingSnapshotCommit which uses file system rename operations for atomicity.

The class provides utility methods including copy() for creating modified instances with different identifiers while preserving other settings, and empty() for creating a minimal environment without catalog integration. This design enables flexible table management that can adapt to different catalog implementations and their capabilities.

Usage

Use CatalogEnvironment when initializing table instances that need catalog context, determining snapshot commit strategies based on catalog capabilities, or propagating catalog settings across table operations.

Code Reference

Source Location

• Repository: Apache_Paimon
• File: paimon-python/pypaimon/catalog/catalog_environment.py

Signature

class CatalogEnvironment:

    def __init__(
            self,
            identifier: Optional[Identifier] = None,
            uuid: Optional[str] = None,
            catalog_loader: Optional[CatalogLoader] = None,
            supports_version_management: bool = False
    ):
        pass

    def snapshot_commit(self, snapshot_manager) -> Optional[SnapshotCommit]:
        pass

    def copy(self, identifier: Identifier) -> 'CatalogEnvironment':
        pass

    @staticmethod
    def empty() -> 'CatalogEnvironment':
        pass

Import

from pypaimon.catalog.catalog_environment import CatalogEnvironment

I/O Contract

Inputs

Name	Type	Required	Description
identifier	Identifier	No	Table identifier (database.table)
uuid	str	No	Unique identifier for tracking
catalog_loader	CatalogLoader	No	Catalog loader for accessing catalog
supports_version_management	bool	No	Whether catalog supports version management (default: False)
snapshot_manager	SnapshotManager	Yes	Snapshot manager for commit operations

Outputs

Name	Type	Description
snapshot_commit	SnapshotCommit	Appropriate snapshot commit implementation
environment	CatalogEnvironment	New or copied environment instance

Usage Examples

from pypaimon.catalog.catalog_environment import CatalogEnvironment
from pypaimon.common.identifier import Identifier
from pypaimon.catalog.catalog_loader import CatalogLoader

# Create empty environment for file-based operations
env = CatalogEnvironment.empty()

# Create environment with catalog support
identifier = Identifier.create("my_database", "my_table")
catalog_loader = CatalogLoader(...)

env = CatalogEnvironment(
    identifier=identifier,
    uuid="550e8400-e29b-41d4-a716-446655440000",
    catalog_loader=catalog_loader,
    supports_version_management=True
)

# Get appropriate snapshot commit strategy
snapshot_manager = ...  # SnapshotManager instance
commit = env.snapshot_commit(snapshot_manager)
# Returns CatalogSnapshotCommit if version management supported,
# otherwise RenamingSnapshotCommit

# Copy environment with different identifier
new_identifier = Identifier.create("my_database", "another_table")
new_env = env.copy(new_identifier)
# Preserves uuid, catalog_loader, and supports_version_management

# Check if version management is supported
if env.supports_version_management and env.catalog_loader:
    print("Using catalog-based version management")
else:
    print("Using file-based snapshot commits")

# Access environment properties
print(f"Table: {env.identifier.get_full_name()}")
print(f"UUID: {env.uuid}")

Related Pages

• Principle:Apache_Paimon_Catalog_Object_Model