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Module h2o_wave.core

Functions​

clone_expando​

def clone_expando(source: Expando, exclude_keys: Union[list, tuple, None] = None, include_keys: Union[list, tuple, None] = None) ‑> Expando

Clone an expando instance. Creates a shallow clone.

Args​
source
The expando to clone.
exclude_keys
Keys to exclude while cloning.
include_keys
Keys to include while cloning.
Returns​

The expando clone.

copy_expando​

def copy_expando(source: Expando, target: Expando, exclude_keys: Union[list, tuple, None] = None, include_keys: Union[list, tuple, None] = None) ‑> Expando

Copy all entries from the source expando instance to the target expando instance.

Args​
source
The expando to copy from.
target
The expando to copy to.
exclude_keys
Keys to exclude while copying.
include_keys
Keys to include while copying.
Returns​

The target expando.

data​

def data(fields: Union[str, tuple, list], size: int = 0, rows: Union[dict, list, None] = None, columns: Union[dict, list, None] = None, pack=False, t: Optional[str] = None) ‑> Union[Data, str]

Create a Data instance for associating data with cards.

data()(fields, size) creates a placeholder for data and allocates memory on the Wave server.

data()(fields, size, rows) creates a placeholder and initializes it with the provided rows.

If pack() is True, the size parameter is ignored, and the function returns a packed string representing the data.

Args​
fields
The names of the fields (columns names) in the data, either a list or tuple or string containing space-separated names.
size
The number of rows to allocate memory for. Positive for fixed buffers, negative for cyclic buffers and zero for variable length buffers.
rows
The rows in this data.
columns
The columns in this data.
pack
True to return a packed string representing the data instead of a Data placeholder.
t
Buffer type. One of 'list', 'map', 'cyclic' or 'fixed'. Overrides the buffer type inferred from the size.
Returns​

Either a Data placeholder or a packed string representing the data.

expando_to_dict​

def expando_to_dict(e: Expando) ‑> dict

Extract an expando's underlying dictionary. Any modifications to the dictionary also affect the original expando.

Args​
e
The expando instance.
Returns​

The expando's dictionary.

marshal​

def marshal(d: Any) ‑> str

Marshal to JSON.

Args​
d
Any object or value.
Returns​

A string containing the JSON-serialized form.

pack​

def pack(data: Any) ‑> str

Pack (compress) the provided value.

Args​
data
Any object or value.

The object or value compressed into a string.

unmarshal​

def unmarshal(s: str) ‑> Any

Unmarshal a JSON string.

Args​
s
A string containing JSON-serialized data.
Returns​

The deserialized object or value.

Classes​

AsyncPage​

class AsyncPage(site: AsyncSite, url: str)

Represents a reference to a remote Wave page. Similar to Page except that this class exposes async methods.

Args​
site
The parent site.
url
The URL of this page.

Methods​

load​

async def load(self) ‑> dict

Retrieve the serialized form of this page from the remote site.

Returns​

The serialized form of this page

save​

async def save(self)

Save the page. Sends all local changes made to this page to the remote site.

Ancestors​

Inherited members​

AsyncSite​

class AsyncSite

Represents a reference to the remote Wave site. Similar to Site except that this class exposes async methods.

Methods​

download​

async def download(self, url: str, path: str) ‑> str

Download a file from the site.

Args​
url
The URL of the file.
path
The local directory or file path to download to. If a directory is provided, the original name of the file is retained.
Returns​

The path to the downloaded file.

load​

async def load(self, url) ‑> dict

Retrieve data at the given URL, typically the serialized form of a page.

Args​
url
The URL to read.
Returns​

The serialized page.

proxy​

async def proxy(self, method: str, url: str, headers: Optional[Dict[str, List[str]]] = None, body: Optional[str] = None)
async def unlink(self, path: str)

Signal the end of a stream.

Args​
path
The path of the stream

unload​

async def unload(self, url: str)

Delete an uploaded file from the site.

Args​
url
The URL of the file to delete.
async def uplink(self, path: str, content_type: str, file: Union[IO[str], IO[bytes], str, bytes]) ‑> str

Create or update a stream of images.

The typical use of this function is to transmit a stream of images to a web page, providing the appearance of a video. The path returned by this function can be passed to ui.image() or ui.image_card() (or even a custom HTML img element). The stream is displayed in browsers using multipart/x-mixed-replace content. Callers must call the unlink() function to signal end-of-stream.

Args​
path
a unique path or name for the stream (e.g. 'foo/bar/qux.png'). Must be a valid URL path.
content_type
The MIME type of the streamed content (e.g. 'image/jpeg', 'image/png', etc.).
file
A file or file-like object (on-disk file, standard I/O, in-memory buffers, sockets or pipes).
Returns​

The stream endpoint, typically used as an image path.

upload​

async def upload(self, files: List[str]) ‑> List[str]

Upload local files to the site.

Args​
files
A list of file paths of the files to be uploaded.
Returns​

A list of remote URLs for the uploaded files, in order.

upload_dir​

async def upload_dir(self, directory: str) ‑> str

WARNING: Experimental and subject to change. Upload whole directory to the site with directory structure preserved.

Args​
directory
Folder to be uploaded.
Returns​

A list of remote URLs for the uploaded directory (always size of 1).

Data​

class Data(fields: Union[str, tuple, list], size: int = 0, data: Union[dict, list, None] = None, t: Optional[str] = None)

Represents a data placeholder. A data placeholder is used to allocate memory on the Wave server to store data.

Args​
fields
The names of the fields (columns names) in the data, either a list or tuple or string containing space-separated names.
size
The number of rows to allocate memory for. Positive for fixed buffers, negative for cyclic buffers and zero for variable length buffers.
data
Initial data. Must be either a key-row dict for variable-length buffers OR a row list for fixed-size and cyclic buffers.
t
Buffer type. One of 'list', 'map', 'cyclic' or 'fixed'. Overrides the buffer type inferred from the size.

Methods​

dump​

def dump(self)

Expando​

class Expando(args: Optional[Dict[~KT, ~VT]] = None)

Represents an object whose members (attributes) can be dynamically added and removed at run time.

Args​
args
An optional dict of attribute-value pairs to initialize the expando instance with.

Page​

class Page(site: Site, url: str)

Represents a reference to a remote Wave page.

Args​
site
The parent site.
url
The URL of this page.

Methods​

load​

def load(self) ‑> dict

Retrieve the serialized form of this page from the remote site.

Returns​

The serialized form of this page

save​

def save(self)

Save the page. Sends all local changes made to this page to the remote site.

Ancestors​

Inherited members​

PageBase​

class PageBase(url: str)

Represents a remote page.

Args​
url
The URL of the remote page.

Methods​

add​

def add(self, key: str, card: Any) ‑> Ref

Add a card to this page.

Args​
key
The card's key. Must uniquely identify the card on the page. Overwrites any other card with the same key.
card
A card. Use one of the ui.*_card() to create cards.
Returns​

A reference to the added card.

drop​

def drop(self)

Delete this page from the remote site. Same as del site[url].

Subclasses​

Ref​

class Ref(page: PageBase, key: str)

Represents a local reference to an element on a Page. Any changes made to this local reference are tracked and sent to the remote Wave server when the page is saved.

ServiceError​

class ServiceError(*args, **kwargs)

Common base class for all non-exit exceptions.

Ancestors​

  • builtins.Exception
  • builtins.BaseException

Site​

class Site

Represents a reference to the remote Wave site. A Site instance is used to obtain references to the site's pages.

Methods​

download​

def download(self, url: str, path: str) ‑> str

Download a file from the site.

Args​
url
The URL of the file.
path
The local directory or file path to download to. If a directory is provided, the original name of the file is retained.
Returns​

The path to the downloaded file.

load​

def load(self, url) ‑> dict

Retrieve data at the given URL, typically the serialized form of a page.

Args​
url
The URL to read.
Returns​

The serialized page.

proxy​

def proxy(self, method: str, url: str, headers: Optional[Dict[str, List[str]]] = None, body: Optional[str] = None)
def unlink(self, path: str)

Signal the end of a stream.

Args​
path
The path of the stream

unload​

def unload(self, url: str)

Delete an uploaded file from the site.

Args​
url
The URL of the file to delete.
def uplink(self, path: str, content_type: str, file: Union[IO[str], IO[bytes], str, bytes]) ‑> str

Create or update a stream of images.

The typical use of this function is to transmit a stream of images to a web page, providing the appearance of a video. The path returned by this function can be passed to ui.image() or ui.image_card() (or even a custom HTML img element). The stream is displayed in browsers using multipart/x-mixed-replace content. Callers must call the unlink() function to signal end-of-stream.

Args​
path
a unique path or name for the stream (e.g. 'foo/bar/qux.png'). Must be a valid URL path.
content_type
The MIME type of the streamed content (e.g. 'image/jpeg', 'image/png', etc.).
file
A file or file-like object (on-disk file, standard I/O, in-memory buffers, sockets or pipes).
Returns​

The stream endpoint, typically used as an image path.

upload​

def upload(self, files: List[str]) ‑> List[str]

Upload local files to the site.

Args​
files
A list of file paths of the files to be uploaded..
Returns​

A list of remote URLs for the uploaded files, in order.

upload_dir​

def upload_dir(self, directory: str) ‑> str

WARNING: Experimental and subject to change. Upload whole directory to the site with directory structure preserved.

Args​
directory
Folder to be uploaded.
Returns​

A list of remote URLs for the uploaded directory (always size of 1).