datagit-sdk

Python SDK for DataGit — Git-style version control for rows in your own PostgreSQL or MySQL database.

pip install datagit-sdk

Installed as datagit-sdk, imported as datagit — the distribution name and the import package are separate in Python, and the import keeps the shorter name.

from decimal import Decimal
from datagit import Client, col

with Client("datagit.internal:443", api_key=KEY) as c:
    items = c.repo("catalog").table("products")

    # Reading a BRANCH. Reads on main need no DataGit at all — query the table.
    for row in items.read(branch="q4-pricing", where=col(3) == "outdoor"):
        print(row)

    # One commit, however many rows.
    with items.transaction(branch="q4-pricing", message="Q4 pricing") as tx:
        tx.update(pk, {1: "TENT-4P", 4: Decimal("268.92")})

Three things this SDK will not let you do

Set a commit author. It comes from the credential. An audit trail whose author is client-supplied is decoration, so there is no field to pass.

Send a decimal as a float. Values are hashed into history, so a rounding difference would change a commit id for data nobody edited. Exact numbers travel as decimal.Decimal and go on the wire as strings.

Build a filter from a string. Filters are typed expression trees with no SQL text form, so there is nothing to inject into. A hostile string passed as a filter value stays a value.

Rows are keyed by column id

Not by name. A rename is metadata-only in DataGit, and keying by name would let a rename silently change what a row means on the wire.

Batch your writes

A commit takes the branch's ref lock, so throughput is commits per second regardless of how many rows each carries. One commit of a thousand rows costs roughly what one commit of one row costs, and a loop of single-row commits is the slowest possible way to write.

Versioning

This package and the npm @glyphsoftware/datagit-sdk package are the same contract twice and release on one version number. A change to the canonical encoding is always a major, even when this SDK's own API is untouched.

Apache 2.0.