ObjectStore#

class composer.utils.ObjectStore[source]#

Abstract class for implementing object stores, such as LibcloudObjectStore and S3ObjectStore.

download_object(object_name, filename, overwrite=False, callback=None)[source]#

Download an object to the specified destination path.

Parameters

object_name (str) – The name of the object to download.
filename (str | Path) – Full path to a file or a directory where the incoming file will be saved.
overwrite (bool, optional) – Whether to overwrite an existing file at filename, if it exists. (default: False)
callback ((int) -> None, optional) – If specified, the callback is periodically called with the number of bytes already downloaded and the total size of the object.

Raises

FileNotFoundError – If the file was not found in the object store.
ObjectStoreTransientError – If there was a transient connection issue with downloading the object.

get_object_size(object_name)[source]#

Get the size of an object, in bytes.

Parameters

object_name (str) – The name of the object.

Returns

int – The object size, in bytes.

Raises

FileNotFoundError – If the file was not found in the object store.
ObjectStoreTransientError – If there was a transient connection issue with getting the object size.

get_uri(object_name)[source]#

Returns the URI for object_name.

Note

This function does not check that object_name is in the object store. It computes the URI statically.

upload_object(object_name, filename, callback=None)[source]#

Upload an object currently located on a disk.

Parameters

object_name (str) – Object name (where object will be stored in the container)
filename (str | Path) – Path the the object on disk
callback ((int, int) -> None, optional) – If specified, the callback is periodically called with the number of bytes uploaded and the total size of the object being uploaded.

Raises

ObjectStoreTransientError – If there was a transient connection issue with uploading the object.