`core.modules.file`¶

Module Contents¶

Classes¶

`DownloadUrlBone`	This bone is used to inject a freshly signed download url into a FileSkel.
`FileLeafSkel`	Default file leaf skeleton.
`FileNodeSkel`	Default file node skeleton.
`File`	Tree module prototype.

Functions¶

`importBlobFromViur2`(dlKey, fileName)
`thumbnailer`(fileSkel, existingFiles, params)
`cloudfunction_thumbnailer`(fileSkel, existingFiles, params)	External Thumbnailer for images.
`startCheckForUnreferencedBlobs`()	Start searching for blob locks that have been recently freed
`doCheckForUnreferencedBlobs`([cursor])
`startCleanupDeletedFiles`()	Increase deletion counter on each blob currently not referenced and delete
`doCleanupDeletedFiles`([cursor])
`start_delete_pending_files`()	Start deletion of pending FileSkels that are older than 7 days.
`__getattr__`(attr)

Attributes¶

`VALID_FILENAME_REGEX`
`GOOGLE_STORAGE_CLIENT`
`PRIVATE_BUCKET_NAME`
`PUBLIC_BUCKET_NAME`
`PUBLIC_DLKEY_SUFFIX`
`_private_bucket`
`_public_bucket`
`FilePath`

core.modules.file.VALID_FILENAME_REGEX¶

core.modules.file.GOOGLE_STORAGE_CLIENT¶

core.modules.file.PRIVATE_BUCKET_NAME¶

core.modules.file.PUBLIC_BUCKET_NAME¶

core.modules.file.PUBLIC_DLKEY_SUFFIX = '_pub'¶

core.modules.file._private_bucket¶

core.modules.file._public_bucket¶

core.modules.file.FilePath¶

core.modules.file.importBlobFromViur2(dlKey, fileName)¶

core.modules.file.thumbnailer(fileSkel, existingFiles, params)¶

core.modules.file.cloudfunction_thumbnailer(fileSkel, existingFiles, params)¶

External Thumbnailer for images.

The corresponding cloudfunction can be found here . https://github.com/viur-framework/viur-cloudfunctions/tree/main/thumbnailer

You can use it like so: main.py:

from viur.core.modules.file import cloudfunction_thumbnailer

conf.file_thumbnailer_url = "https://xxxxx.cloudfunctions.net/imagerenderer"
conf.file_derivations = {"thumbnail": cloudfunction_thumbnailer}

conf.derives_pdf = {
    "thumbnail": [{"width": 1920,"sites":"1,2"}]
}

skeletons/xxx.py: .. code-block:: python

test = FileBone(derive=conf.derives_pdf)

class core.modules.file.DownloadUrlBone(*, compute=None, defaultValue=None, descr=None, getEmptyValueFunc=None, indexed=True, isEmptyFunc=None, languages=None, multiple=False, params=None, readOnly=None, required=False, searchable=False, type_suffix='', unique=None, vfunc=None, visible=True, clone_behavior=None)¶

Bases: viur.core.bones.BaseBone

This bone is used to inject a freshly signed download url into a FileSkel.

Initializes a new Bone.

Parameters:

compute (Compute) –
defaultValue (Any) –
descr (Optional[str | viur.core.i18n.translate]) –
getEmptyValueFunc (callable) –
indexed (bool) –
isEmptyFunc (callable) –
languages (None | list[str]) –
multiple (bool | MultipleConstraints) –
params (dict) –
readOnly (bool) –
required (bool | list[str] | tuple[str]) –
searchable (bool) –
type_suffix (str) –
unique (None | UniqueValue) –
vfunc (callable) –
visible (bool) –
clone_behavior (CloneBehavior | CloneStrategy | None) –

unserialize(skel, name)¶

Deserialize bone data from the datastore and populate the bone with the deserialized values.

This function is the inverse of the serialize function. It converts data from the datastore into a format that can be used by the bones in the skeleton.

Parameters:

skel – A SkeletonInstance object containing the values to be deserialized.
name – The property name of the bone in its Skeleton (not the description).

Returns:

True if deserialization is successful, False otherwise.

class core.modules.file.FileLeafSkel(*args, **kwargs)¶

Bases: viur.core.prototypes.tree.TreeSkel

Default file leaf skeleton.

kindName = 'file'¶

size¶

dlkey¶

name¶

mimetype¶

weak¶

pending¶

width¶

height¶

downloadUrl¶

derived¶

pendingparententry¶

crc32c_checksum¶

md5_checksum¶

public¶

serving_url¶

classmethod _inject_serving_url(skel)¶

Inject the serving url for public image files into a FileSkel

Parameters:: skel (viur.core.skeleton.SkeletonInstance) –
Return type:: None

preProcessBlobLocks(locks)¶: Ensure that our dlkey is locked even if we don’t have a filebone here

classmethod refresh(skel)¶

Refresh the bones current content.

This function causes a refresh of all relational bones and their associated information.

classmethod write(skel, **kwargs)¶

Write current Skeleton to the datastore.

Stores the current data of this instance into the database. If an key value is set to the object, this entity will ne updated; Otherwise a new entity will be created.

To read a Skeleton object from the data store, see read().

Parameters:

key – Allows to specify a key that is set to the skeleton and used for writing.
update_relations – If False, this entity won’t be marked dirty; This avoids from being fetched by the background task updating relations.

Returns:

The Skeleton.

class core.modules.file.FileNodeSkel(*args, **kwargs)¶

Bases: viur.core.prototypes.tree.TreeSkel

Default file node skeleton.

kindName = 'file_rootNode'¶

name¶

rootNode¶

public¶

viurCurrentSeoKeys¶

class core.modules.file.File(moduleName, modulePath, *args, **kwargs)¶

Bases: viur.core.prototypes.tree.Tree

Tree module prototype.

It is used for hierarchical structures, either as a tree with nodes and leafs, or as a hierarchy with nodes only.

PENDING_POSTFIX = ' (pending)'¶

DOWNLOAD_URL_PREFIX = '/file/download/'¶

INTERNAL_SERVING_URL_PREFIX = '/file/serve/'¶

MAX_FILENAME_LEN = 256¶

IMAGE_META_MAX_SIZE: viur.core.decorators.t.Final[int]¶: Maximum size of image files that should be analysed in set_image_meta(). Default: 10 MiB

leafSkelCls¶

nodeSkelCls¶

handler = 'tree.simple.file'¶

adminInfo¶

roles¶

default_order = 'name'¶

SERVE_VALID_OPTIONS¶: Valid modification option shorts for the serve-function. This is passed-through to the Google UserContent API, and hast to be supported there.

SERVE_VALID_FORMATS¶: Valid file-formats to the serve-function. This is passed-through to the Google UserContent API, and hast to be supported there.

static get_bucket(dlkey)¶

Retrieves a Google Cloud Storage bucket for the given dlkey.

Parameters:: dlkey (str) –
Return type:: google.cloud.storage.bucket.Bucket

static is_valid_filename(filename)¶

Verifies a valid filename.

The filename should be valid on Linux, Mac OS and Windows. It should not be longer than MAX_FILENAME_LEN chars.

Rule set: https://stackoverflow.com/a/31976060/3749896 Regex test: https://regex101.com/r/iBYpoC/1

Parameters:: filename (str) –
Return type:: bool

static hmac_sign(data)¶

Parameters:: data (viur.core.decorators.t.Any) –
Return type:: str

static hmac_verify(data, signature)¶

Parameters:

data (viur.core.decorators.t.Any) –
signature (str) –

Return type:

bool

static create_internal_serving_url(serving_url, size=0, filename='', options='', download=False)¶

Helper function to generate an internal serving url (endpoint: /file/serve) from a Google serving url.

This is needed to hide requests to Google as they are internally be routed, and can be the result of a legal requirement like GDPR.

Parameters:

serving_url (str) – Is the original serving URL as generated from FileLeafSkel._inject_serving_url()
size (int) – Optional size setting
filename (str) – Optonal filename setting
options (str) – Additional options parameter-pass through to /file/serve
download (bool) – Download parameter-pass through to /file/serve

Return type:

str

static create_download_url(dlkey, filename, derived=False, expires=datetime.timedelta(hours=1), download_filename=None)¶

Utility function that creates a signed download-url for the given folder/filename combination

Parameters:

folder – The GCS-Folder (= the download-key) for that file
filename (str) – The name of the file. Either the original filename or the name of a derived file.
derived (bool) – True, if it points to a derived file, False if it points to the original uploaded file
expires (viur.core.decorators.t.Optional[datetime.timedelta | int]) – None if the file is supposed to be public (which causes it to be cached on the google ede caches), otherwise a datetime.timedelta of how long that link should be valid
download_filename (viur.core.decorators.t.Optional[str]) – If set, browser is enforced to download this blob with the given alternate filename
dlkey (str) –

Returns:

The signed download-url relative to the current domain (eg /download/…)

Return type:

str

static parse_download_url(url)¶

Parses a file download URL in the format /file/download/xxxx?sig=yyyy into its FilePath.

If the URL cannot be parsed, the function returns None.

Parameters:: url – The file download URL to be parsed.
Returns:: A FilePath on success, None otherwise.
Return type:: viur.core.decorators.t.Optional[FilePath]

static create_src_set(file, expires=datetime.timedelta(hours=1), width=None, height=None, language=None)¶

Generates a string suitable for use as the srcset tag in html. This functionality provides the browser with a list of images in different sizes and allows it to choose the smallest file that will fill it’s viewport without upscaling.

Parameters:

file (viur.core.decorators.t.Union[viur.core.skeleton.SkeletonInstance, dict, str]) – The file skeleton (or if multiple=True a single value from it) to generate the srcset.
expires (viur.core.decorators.t.Optional[datetime.timedelta | int]) – None if the file is supposed to be public (which causes it to be cached on the google edecaches), otherwise it’s lifetime in seconds
width (viur.core.decorators.t.Optional[int]) – A list of widths that should be included in the srcset. If a given width is not available, it will be skipped.
height (viur.core.decorators.t.Optional[int]) – A list of heights that should be included in the srcset. If a given height is not available, it will be skipped.
language (viur.core.decorators.t.Optional[str]) – Language overwrite if file has multiple languages, and we want to explicitly specify one

Returns:

The srctag generated or an empty string if a invalid file object was supplied

Return type:

str

write(filename, content, mimetype='text/plain', width=None, height=None, public=False)¶

Write a file from any buffer into the file module.

Parameters:

filename (str) – Filename to be written.
content (viur.core.decorators.t.Any) – The file content to be written, as bytes-like object.
mimetype (str) – The file’s mimetype.
width (int) – Optional width information for the file.
height (int) – Optional height information for the file.
public (bool) – True if the file should be publicly accessible.

Returns:

Returns the key of the file object written. This can be associated e.g. with a FileBone.

Return type:

viur.core.db.Key

read(key=None, path=None)¶

Read a file from the Cloud Storage.

If a key and a path are provided, the key is preferred. This means that the entry in the db is searched first and if this is not found, the path is used.

Parameters:

key (viur.core.db.Key | int | str | None) – Key of the LeafSkel that contains the “dlkey” and the “name”.
path (str | None) – The path of the file in the Cloud Storage Bucket.

Returns:

Returns the file as a io.BytesIO buffer and the content-type

Return type:

tuple[io.BytesIO, str]

deleteRecursive(parentKey)¶

Recursively processes a delete request.

This will delete all entries which are children of nodeKey, except key nodeKey.

Parameters:: parentKey – URL-safe key of the node which children should be deleted.

getUploadURL(fileName, mimeType, size=None, node=None, authData=None, authSig=None, public=False)¶

Parameters:

fileName (str) –
mimeType (str) –
size (viur.core.decorators.t.Optional[int]) –
node (viur.core.decorators.t.Optional[str | viur.core.db.Key]) –
authData (viur.core.decorators.t.Optional[str]) –
authSig (viur.core.decorators.t.Optional[str]) –
public (bool) –

download(blobKey, fileName='', download=False, sig='', *args, **kwargs)¶

Download a file. :param blobKey: The unique blob key of the file. :param fileName: Optional filename to provide in the header. :param download: Set header to attachment retrival, set explictly to “1” if download is wanted.

Parameters:

blobKey (str) –
fileName (str) –
download (bool) –
sig (str) –

serve(host, key, size=None, filename=None, options='', download=False)¶

Requests an image using the serving url to bypass direct Google requests.

Parameters:

host (str) – the google host prefix i.e. lh3
key (str) – the serving url key
size (viur.core.decorators.t.Optional[int]) – the target image size
filename (viur.core.decorators.t.Optional[str]) – a random string with an extention, valid extentions are (defined in File.SERVE_VALID_FORMATS).
options (str) –
- seperated options (defined in File.SERVE_VALID_OPTIONS).
c - crop p - face crop fv - vertrical flip fh - horizontal flip rXXX - rotate 90, 180, 270 nu - no upscale
download (bool) – Serves the content as download (Content-Disposition) or not.

Returns:

Returns the requested content on success, raises a proper HTTP exception otherwise.

add(skelType, node=None, *args, **kwargs)¶

Add a new entry with the given parent node, and render the entry, eventually with error notes on incorrect data. Data is taken by any other arguments in kwargs.

The function performs several access control checks on the requested entity before it is added.

core.modules.file¶

Module Contents¶

Classes¶

Functions¶

Attributes¶

`core.modules.file`¶