Vane Data / Reference

File constructors

Constructors build FILE-family expressions. By default, file, image_file, audio_file, and video_file do not access the referenced object; to_file, try_to_file, and from_files resolve storage when executed.

Signature

example.py

vane.file(url, content_type=None, position=None, size=None, checksum=None) -> Expression
vane.image_file(url_or_file, verify=False) -> Expression
vane.audio_file(url_or_file, verify=False) -> Expression
vane.video_file(url_or_file, verify=False) -> Expression
vane.to_file(path) -> Expression
vane.try_to_file(path) -> Expression
vane.from_files(path, *, connection=None) -> Relation

SQL: file(url, content_type, position, size, checksum), image_file(url_or_file [, verify]), audio_file(url_or_file [, verify]), video_file(url_or_file [, verify]), to_file(path), and try_to_file(path). In SQL, file requires all five arguments; the Python form defaults the optional fields to None. from_files is Python-only.

expr.as_file(media_type=MediaType.unknown()) is the Expression method form: it builds the same FILE-family expression from the expression's string value, with media_type selecting FILE, IMAGEFILE, AUDIOFILE, or VIDEOFILE.

Parameters

Name	Type	Description	Default
url	String or Expression	Object URL	Required
content_type	String, Expression, or None	Declared MIME type	None
position / size	Integer, Expression, or None	Optional byte window into the object	None
checksum	String, Expression, or None	Declared checksum	None
url_or_file	String, FILE value, or Expression	URL or FILE view to re-type as IMAGEFILE/AUDIOFILE/VIDEOFILE	Required
verify	bool or Expression	Verify bounded content when constructing the value	False
path	String, Expression, or list of strings (from_files)	Path(s) resolved to FILE	Required

Returns and errors

file, to_file, and try_to_file return FILE; image_file/audio_file/video_file return the matching typed FILE. to_file and try_to_file open the object at execution and return its complete logical view (position = 0, size = object size); to_file raises on failure, while try_to_file returns NULL for recoverable access failures. from_files returns a one-column relation of canonical FILE values, built on list_files. file never accesses the object; the typed constructors access it only when verify=True performs a bounded content check.

Example