Base Dumper

Abstract base classes and common utilities for database dumpers in the dbhose-airflow ecosystem.

Overview

base_dumper provides the foundation for building database dumpers with consistent interfaces for reading,

writing, and transferring data between different database systems.

It includes abstract classes, common data structures, and utility functions.

Features

• Abstract Base Classes: BaseDumper, AbstractCursor, ExampleReader
• Multi-query Support: Automatic splitting and execution of multiple SQL statements
• Data Format Support: Convert between database tables and Python, pandas, or polars
• Streaming: Memory-efficient data transfer between sources
• Transaction Management: Configurable isolation levels
• Logging: Built-in logging with file and console output
• Compression: Integration with light_compressor for compressed dumps

Installation

pip install base-dumper

Core Components

BaseDumper

Abstract dumper class that all database-specific dumpers should inherit from.

from logging import Logger
from base_dumper import (
    BaseDumper,
    CompressionMethod,
    DBConnector,
    DumperMode,
    IsolationLevel,
)

class MyNewDumper(BaseDumper):
    def __init__(
        self,
        connector: DBConnector,
        compression_method: CompressionMethod,
        logger: Logger,
        timeout: int,
        isolation: IsolationLevel,
        mode: DumperMode,
    ):
        super().__init__(
            connector,
            compression_method,
            logger,
            timeout,
            isolation,
            mode,
        )
        # Implement MyNewDumper init
        ...

    # Implement abstract methods
    ...

Data Transfer Methods

• read_dump: Read data from source to file
• write_dump: Write data from file to destination
• write_between: Transfer directly between databases
• to_reader: Get data as stream object
• from_rows/pandas/polars: Write from Python data structures

Utilities

• chunk_query: Split multi-query strings into individual statements
• transfer_diagram: Generate visual representation of data transfer
• random_name: Generate random names for temporary objects
• DBConnector: Database connection parameters container

Usage Example

from base_dumper import DBConnector, CompressionMethod

# Create connector
connector = DBConnector(
    host="localhost",
    dbname="mydb",
    user="user",
    password="pass",
    port=5432
)

# Initialize dumper (with concrete implementation)
dumper = MyNewDumper(
    connector=connector,
    compression_method=CompressionMethod.ZSTD,
    isolation=IsolationLevel.committed
)

# Read dump to file
with open("dump.sql.zst", "wb") as f:
    dumper.read_dump(f, table_name="users")

# Convert to pandas DataFrame
reader = dumper.to_reader(table_name="users")
df = reader.to_pandas()

Requirements

• Python >= 3.10
• light-compressor
• sqlparse
• pandas
• polars