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API Reference

Source

Source is the input a load step reads — files, a folder with globs, or a SQL query the user picks. Reference for Source.file, Source.sql, Source.of, and read.

A Source is the input a load step reads. Annotate a step parameter Source and LSD injects a reader bound to whatever the user picks; or construct one directly with Source.file / Source.sql / Source.of to drive a load in Python. Either way, source.read() returns a Table — the picker's choice and the code path are the same object, so a tool works identically whether the source is chosen in the UI or in a script.

Usage#

Python
from lsdtools import Tool, Source, Table

tool = Tool("io")

@tool.load(source_kinds=("file",))
def load_it(src: Source) -> Table:
    return src.read()
# → reads whatever file the user selects in the node's form

Where to start#

LearnLoad steps · Params vs ports

ExamplesFile loader · Clean a CSV

APITool · Table · Context

Properties

Class methods

Methods

By LSD Team · Last updated Jul 17, 2026 Ask on Discord View as Markdown