Track and version objects

Track and version any JSON-serializable object in W&B Weave

Objects

An Object is versioned, serializable data. Weave automatically versions objects when they change and creates an immutable history. Objects include:

• Datasets: Collections of examples for evaluation
• Models: Configurations and parameters for your LLM logic
• Prompts: Versioned prompt templates

dataset = weave.Dataset(
    name="test-cases",
    rows=[
        {"input": "What is 2+2?", "expected": "4"},
        {"input": "What is the capital of France?", "expected": "Paris"},
    ]
)
weave.publish(dataset)

Publishing an object

Weave’s serialization layer saves and versions objects.

Python

import weave
# Initialize tracking to the project 'intro-example'
weave.init('intro-example')
# Save a list, giving it the name 'cat-names'
weave.publish(['felix', 'jimbo', 'billie'], 'cat-names')

TypeScript

Publishing in TypeScript is still early, so not all objects are fully supported yet.

import * as weave from 'weave'

// Initialize tracking to the project 'intro-example'
const client = await weave.init('intro-example')

// Save an array, giving it the name 'cat-names'
client.publish(['felix', 'jimbo', 'billie'], 'cat-names')

When you save an object with a name, Weave creates the first version of that object if it does not exist.

Get an object back

Python

weave.publish returns a Ref. You can call .get() on any Ref to get the object back.

You can construct a ref and then fetch the object back.

weave.init('intro-example')
cat_names = weave.ref('cat-names').get()

TypeScript

This feature is not available in TypeScript yet.

Delete an object

Python

To delete a version of an object, call .delete() on the object ref.

weave.init('intro-example')
cat_names_ref = weave.ref('cat-names:v1')
cat_names_ref.delete()

Accessing a deleted object returns an error. Resolving an object that has a reference to a deleted object returns a DeletedRef in place of the deleted object.

TypeScript

This feature is not available in TypeScript yet.

Ref styles

A fully qualified Weave object ref URI looks like this:

weave://<entity>/<project>/object/<object_name>:<object_version>

• entity: wandb entity (username or team)
• project: wandb project
• object_name: object name
• object_version: either a version hash, a string like v0, v1…, or an alias like “:latest”. All objects have the “:latest” alias.

You can construct refs with a few different styles.

• weave.ref(<name>): requires weave.init(<project>) to have been called. Refers to the “:latest” version.
• weave.ref(<name>:<version>): requires weave.init(<project>) to have been called.
• weave.ref(<fully_qualified_ref_uri>): can be constructed without calling weave.init.