Artifact

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Flexible and lightweight building block for dataset and model versioning.

Construct an empty W&B Artifact. Populate an artifacts contents with methods that begin with add. Once the artifact has all the desired files, you can call wandb.log_artifact() to log it.

Args
name A human-readable name for the artifact. Use the name to identify a specific artifact in the W&B App UI or programmatically. You can interactively reference an artifact with the use_artifact Public API. A name can contain letters, numbers, underscores, hyphens, and dots. The name must be unique across a project.
type The artifact’s type. Use the type of an artifact to both organize and differentiate artifacts. You can use any string that contains letters, numbers, underscores, hyphens, and dots. Common types include dataset or model. Note: Some types are reserved for internal use and cannot be set by users. Such types include job and types that start with wandb-.
description A description of the artifact. For Model or Dataset Artifacts, add documentation for your standardized team model or dataset card. View an artifact’s description programmatically with the Artifact.description attribute or programmatically with the W&B App UI. W&B renders the description as markdown in the W&B App.
metadata Additional information about an artifact. Specify metadata as a dictionary of key-value pairs. You can specify no more than 100 total keys.
incremental Use Artifact.new_draft() method instead to modify an existing artifact.
use_as Deprecated.
is_link Boolean indication of if the artifact is a linked artifact(True) or source artifact(False).
Returns
An Artifact object.
Attributes
aliases List of one or more semantically-friendly references or identifying “nicknames” assigned to an artifact version. Aliases are mutable references that you can programmatically reference. Change an artifact’s alias with the W&B App UI or programmatically. See Create new artifact versions for more information.
collection The collection this artifact was retrieved from. A collection is an ordered group of artifact versions. If this artifact was retrieved from a portfolio / linked collection, that collection will be returned rather than the collection that an artifact version originated from. The collection that an artifact originates from is known as the source sequence.
commit_hash The hash returned when this artifact was committed.
created_at Timestamp when the artifact was created.
description A description of the artifact.
digest The logical digest of the artifact. The digest is the checksum of the artifact’s contents. If an artifact has the same digest as the current latest version, then log_artifact is a no-op.
entity The name of the entity that the artifact collection belongs to. If the artifact is a link, the entity will be the entity of the linked artifact.
file_count The number of files (including references).
history_step The nearest step at which history metrics were logged for the source run of the artifact.
id The artifact’s ID.
is_link Boolean flag indicating if the artifact is a link artifact. True: The artifact is a link artifact to a source artifact. False: The artifact is a source artifact.
linked_artifacts Returns a list of all the linked artifacts of a source artifact. If the artifact is a link artifact (artifact.is_link == True), it will return an empty list. Limited to 500 results.
manifest The artifact’s manifest. The manifest lists all of its contents, and can’t be changed once the artifact has been logged.
metadata User-defined artifact metadata. Structured data associated with the artifact.
name The artifact name and version of the artifact. A string with the format {collection}:{alias}. If fetched before an artifact is logged/saved, the name won’t contain the alias. If the artifact is a link, the name will be the name of the linked artifact.
project The name of the project that the artifact collection belongs to. If the artifact is a link, the project will be the project of the linked artifact.
qualified_name The entity/project/name of the artifact. If the artifact is a link, the qualified name will be the qualified name of the linked artifact path.
size The total size of the artifact in bytes. Includes any references tracked by this artifact.
source_artifact Returns the source artifact. The source artifact is the original logged artifact. If the artifact itself is a source artifact (artifact.is_link == False), it will return itself.
source_collection The artifact’s source collection. The source collection is the collection that the artifact was logged from.
source_entity The name of the entity of the source artifact.
source_name The artifact name and version of the source artifact. A string with the format {source_collection}:{alias}. Before the artifact is saved, contains only the name since the version is not yet known.
source_project The name of the project of the source artifact.
source_qualified_name The source_entity/source_project/source_name of the source artifact.
source_version The source artifact’s version. A string with the format v{number}.
state The status of the artifact. One of: “PENDING”, “COMMITTED”, or “DELETED”.
tags List of one or more tags assigned to this artifact version.
ttl The time-to-live (TTL) policy of an artifact. Artifacts are deleted shortly after a TTL policy’s duration passes. If set to None, the artifact deactivates TTL policies and will be not scheduled for deletion, even if there is a team default TTL. An artifact inherits a TTL policy from the team default if the team administrator defines a default TTL and there is no custom policy set on an artifact.
type The artifact’s type. Common types include dataset or model.
updated_at The time when the artifact was last updated.
url Constructs the URL of the artifact.
use_as Deprecated.
version The artifact’s version. A string with the format v{number}. If the artifact is a link artifact, the version will be from the linked collection.

Methods

add

View source

add(
    obj: WBValue,
    name: StrPath,
    overwrite: bool = (False)
) -> ArtifactManifestEntry

Add wandb.WBValue obj to the artifact.

Args
obj The object to add. Currently support one of Bokeh, JoinedTable, PartitionedTable, Table, Classes, ImageMask, BoundingBoxes2D, Audio, Image, Video, Html, Object3D
name The path within the artifact to add the object.
overwrite If True, overwrite existing objects with the same file path (if applicable).
Returns
The added manifest entry
Raises
ArtifactFinalizedError You cannot make changes to the current artifact version because it is finalized. Log a new artifact version instead.

add_dir

View source

add_dir(
    local_path: str,
    name: (str | None) = None,
    skip_cache: (bool | None) = (False),
    policy: (Literal['mutable', 'immutable'] | None) = "mutable",
    merge: bool = (False)
) -> None

Add a local directory to the artifact.

Args
local_path The path of the local directory.
name The subdirectory name within an artifact. The name you specify appears in the W&B App UI nested by artifact’s type. Defaults to the root of the artifact.
skip_cache If set to True, W&B will not copy/move files to the cache while uploading
policy “mutable”
merge If False (default), throws ValueError if a file was already added in a previous add_dir call and its content has changed. If True, overwrites existing files with changed content. Always adds new files and never removes files. To replace an entire directory, pass a name when adding the directory using add_dir(local_path, name=my_prefix) and call remove(my_prefix) to remove the directory, then add it again.
Raises
ArtifactFinalizedError You cannot make changes to the current artifact version because it is finalized. Log a new artifact version instead.
ValueError Policy must be “mutable” or “immutable”

add_file

View source

add_file(
    local_path: str,
    name: (str | None) = None,
    is_tmp: (bool | None) = (False),
    skip_cache: (bool | None) = (False),
    policy: (Literal['mutable', 'immutable'] | None) = "mutable",
    overwrite: bool = (False)
) -> ArtifactManifestEntry

Add a local file to the artifact.

Args
local_path The path to the file being added.
name The path within the artifact to use for the file being added. Defaults to the basename of the file.
is_tmp If true, then the file is renamed deterministically to avoid collisions.
skip_cache If True, W&B will not copy files to the cache after uploading.
policy By default, set to “mutable”. If set to “mutable”, create a temporary copy of the file to prevent corruption during upload. If set to “immutable”, disable protection and rely on the user not to delete or change the file.
overwrite If True, overwrite the file if it already exists.
Returns
The added manifest entry.
Raises
ArtifactFinalizedError You cannot make changes to the current artifact version because it is finalized. Log a new artifact version instead.
ValueError Policy must be “mutable” or “immutable”

add_reference

View source

add_reference(
    uri: (ArtifactManifestEntry | str),
    name: (StrPath | None) = None,
    checksum: bool = (True),
    max_objects: (int | None) = None
) -> Sequence[ArtifactManifestEntry]

Add a reference denoted by a URI to the artifact.

Unlike files or directories that you add to an artifact, references are not uploaded to W&B. For more information, see Track external files.

By default, the following schemes are supported:

  • http(s): The size and digest of the file will be inferred by the Content-Length and the ETag response headers returned by the server.
  • s3: The checksum and size are pulled from the object metadata. If bucket versioning is enabled, then the version ID is also tracked.
  • gs: The checksum and size are pulled from the object metadata. If bucket versioning is enabled, then the version ID is also tracked.
  • https, domain matching *.blob.core.windows.net (Azure): The checksum and size are be pulled from the blob metadata. If storage account versioning is enabled, then the version ID is also tracked.
  • file: The checksum and size are pulled from the file system. This scheme is useful if you have an NFS share or other externally mounted volume containing files you wish to track but not necessarily upload.

For any other scheme, the digest is just a hash of the URI and the size is left blank.

Args
uri The URI path of the reference to add. The URI path can be an object returned from Artifact.get_entry to store a reference to another artifact’s entry.
name The path within the artifact to place the contents of this reference.
checksum Whether or not to checksum the resource(s) located at the reference URI. Checksumming is strongly recommended as it enables automatic integrity validation. Disabling checksumming will speed up artifact creation but reference directories will not iterated through so the objects in the directory will not be saved to the artifact. We recommend setting checksum=False when adding reference objects, in which case a new version will only be created if the reference URI changes.
max_objects The maximum number of objects to consider when adding a reference that points to directory or bucket store prefix. By default, the maximum number of objects allowed for Amazon S3, GCS, Azure, and local files is 10,000,000. Other URI schemas do not have a maximum.
Returns
The added manifest entries.
Raises
ArtifactFinalizedError You cannot make changes to the current artifact version because it is finalized. Log a new artifact version instead.

checkout

View source

checkout(
    root: (str | None) = None
) -> str

Replace the specified root directory with the contents of the artifact.

WARNING: This will delete all files in root that are not included in the artifact.

Args
root The directory to replace with this artifact’s files.
Returns
The path of the checked out contents.
Raises
ArtifactNotLoggedError If the artifact is not logged.

delete

View source

delete(
    delete_aliases: bool = (False)
) -> None

Delete an artifact and its files.

If called on a linked artifact (i.e. a member of a portfolio collection): only the link is deleted, and the source artifact is unaffected.

Use artifact.unlink() instead of artifact.delete() to remove a link between a source artifact and a linked artifact.

Args
delete_aliases If set to True, deletes all aliases associated with the artifact. Otherwise, this raises an exception if the artifact has existing aliases. This parameter is ignored if the artifact is linked (i.e. a member of a portfolio collection).
Raises
ArtifactNotLoggedError If the artifact is not logged.

download

View source

download(
    root: (StrPath | None) = None,
    allow_missing_references: bool = (False),
    skip_cache: (bool | None) = None,
    path_prefix: (StrPath | None) = None,
    multipart: (bool | None) = None
) -> FilePathStr

Download the contents of the artifact to the specified root directory.

Existing files located within root are not modified. Explicitly delete root before you call download if you want the contents of root to exactly match the artifact.

Args
root The directory W&B stores the artifact’s files.
allow_missing_references If set to True, any invalid reference paths will be ignored while downloading referenced files.
skip_cache If set to True, the artifact cache will be skipped when downloading and W&B will download each file into the default root or specified download directory.
path_prefix If specified, only files with a path that starts with the given prefix will be downloaded. Uses unix format (forward slashes).
multipart If set to None (default), the artifact will be downloaded in parallel using multipart download if individual file size is greater than 2GB. If set to True or False, the artifact will be downloaded in parallel or serially regardless of the file size.
Returns
The path to the downloaded contents.
Raises
ArtifactNotLoggedError If the artifact is not logged.

file

View source

file(
    root: (str | None) = None
) -> StrPath

Download a single file artifact to the directory you specify with root.

Args
root The root directory to store the file. Defaults to ‘./artifacts/self.name/’.
Returns
The full path of the downloaded file.
Raises
ArtifactNotLoggedError If the artifact is not logged.
ValueError If the artifact contains more than one file.

files

View source

files(
    names: (list[str] | None) = None,
    per_page: int = 50
) -> ArtifactFiles

Iterate over all files stored in this artifact.

Args
names The filename paths relative to the root of the artifact you wish to list.
per_page The number of files to return per request.
Returns
An iterator containing File objects.
Raises
ArtifactNotLoggedError If the artifact is not logged.

finalize

View source

finalize() -> None

Finalize the artifact version.

You cannot modify an artifact version once it is finalized because the artifact is logged as a specific artifact version. Create a new artifact version to log more data to an artifact. An artifact is automatically finalized when you log the artifact with log_artifact.

get

View source

get(
    name: str
) -> (WBValue | None)

Get the WBValue object located at the artifact relative name.

Args
name The artifact relative name to retrieve.
Returns
W&B object that can be logged with wandb.log() and visualized in the W&B UI.
Raises
ArtifactNotLoggedError if the artifact isn’t logged or the run is offline

get_added_local_path_name

View source

get_added_local_path_name(
    local_path: str
) -> (str | None)

Get the artifact relative name of a file added by a local filesystem path.

Args
local_path The local path to resolve into an artifact relative name.
Returns
The artifact relative name.

get_entry

View source

get_entry(
    name: StrPath
) -> ArtifactManifestEntry

Get the entry with the given name.

Args
name The artifact relative name to get
Returns
A W&B object.
Raises
ArtifactNotLoggedError if the artifact isn’t logged or the run is offline.
KeyError if the artifact doesn’t contain an entry with the given name.

get_path

View source

get_path(
    name: StrPath
) -> ArtifactManifestEntry

Deprecated. Use get_entry(name).

is_draft

View source

is_draft() -> bool

Check if artifact is not saved.

Returns: Boolean. False if artifact is saved. True if artifact is not saved.

json_encode

View source

json_encode() -> dict[str, Any]

Returns the artifact encoded to the JSON format.

Returns
A dict with string keys representing attributes of the artifact.

View source

link(
    target_path: str,
    aliases: (list[str] | None) = None
) -> (Artifact | None)

Link this artifact to a portfolio (a promoted collection of artifacts).

Args
target_path The path to the portfolio inside a project. The target path must adhere to one of the following schemas {portfolio}, {project}/{portfolio} or {entity}/{project}/{portfolio}. To link the artifact to the Model Registry, rather than to a generic portfolio inside a project, set target_path to the following schema {"model-registry"}/{Registered Model Name} or {entity}/{"model-registry"}/{Registered Model Name}.
aliases A list of strings that uniquely identifies the artifact inside the specified portfolio.
Raises
ArtifactNotLoggedError If the artifact is not logged.
Returns
The linked artifact if linking was successful, otherwise None.

logged_by

View source

logged_by() -> (Run | None)

Get the W&B run that originally logged the artifact.

Returns
The name of the W&B run that originally logged the artifact.
Raises
ArtifactNotLoggedError If the artifact is not logged.

new_draft

View source

new_draft() -> Artifact

Create a new draft artifact with the same content as this committed artifact.

Modifying an existing artifact creates a new artifact version known as an “incremental artifact”. The artifact returned can be extended or modified and logged as a new version.

Returns
An Artifact object.
Raises
ArtifactNotLoggedError If the artifact is not logged.

new_file

View source

@contextlib.contextmanager
new_file(
    name: str,
    mode: str = "x",
    encoding: (str | None) = None
) -> Iterator[IO]

Open a new temporary file and add it to the artifact.

Args
name The name of the new file to add to the artifact.
mode The file access mode to use to open the new file.
encoding The encoding used to open the new file.
Returns
A new file object that can be written to. Upon closing, the file will be automatically added to the artifact.
Raises
ArtifactFinalizedError You cannot make changes to the current artifact version because it is finalized. Log a new artifact version instead.

remove

View source

remove(
    item: (StrPath | ArtifactManifestEntry)
) -> None

Remove an item from the artifact.

Args
item The item to remove. Can be a specific manifest entry or the name of an artifact-relative path. If the item matches a directory all items in that directory will be removed.
Raises
ArtifactFinalizedError You cannot make changes to the current artifact version because it is finalized. Log a new artifact version instead.
FileNotFoundError If the item isn’t found in the artifact.

save

View source

save(
    project: (str | None) = None,
    settings: (wandb.Settings | None) = None
) -> None

Persist any changes made to the artifact.

If currently in a run, that run will log this artifact. If not currently in a run, a run of type “auto” is created to track this artifact.

Args
project A project to use for the artifact in the case that a run is not already in context.
settings A settings object to use when initializing an automatic run. Most commonly used in testing harness.

View source

unlink() -> None

Unlink this artifact if it is currently a member of a portfolio (a promoted collection of artifacts).

Raises
ArtifactNotLoggedError If the artifact is not logged.
ValueError If the artifact is not linked, i.e. it is not a member of a portfolio collection.

used_by

View source

used_by() -> list[Run]

Get a list of the runs that have used this artifact and its linked artifacts.

Returns
A list of Run objects.
Raises
ArtifactNotLoggedError If the artifact is not logged.

verify

View source

verify(
    root: (str | None) = None
) -> None

Verify that the contents of an artifact match the manifest.

All files in the directory are checksummed and the checksums are then cross-referenced against the artifact’s manifest. References are not verified.

Args
root The directory to verify. If None artifact will be downloaded to ‘./artifacts/self.name/’.
Raises
ArtifactNotLoggedError If the artifact is not logged.
ValueError If the verification fails.

wait

View source

wait(
    timeout: (int | None) = None
) -> Artifact

If needed, wait for this artifact to finish logging.

Args
timeout The time, in seconds, to wait.
Returns
An Artifact object.

__getitem__

View source

__getitem__(
    name: str
) -> (WBValue | None)

Get the WBValue object located at the artifact relative name.

Args
name The artifact relative name to get.
Returns
W&B object that can be logged with wandb.log() and visualized in the W&B UI.
Raises
ArtifactNotLoggedError If the artifact isn’t logged or the run is offline.

__setitem__

View source

__setitem__(
    name: str,
    item: WBValue
) -> ArtifactManifestEntry

Add item to the artifact at path name.

Args
name The path within the artifact to add the object.
item The object to add.
Returns
The added manifest entry
Raises
ArtifactFinalizedError You cannot make changes to the current artifact version because it is finalized. Log a new artifact version instead.

Last modified July 3, 2025