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perspective-dev--perspective/rust/perspective-python/src/client/client_async.rs
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2026-07-13 12:25:07 +08:00

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Rust

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// ┃ Copyright (c) 2017, the Perspective Authors. ┃
// ┃ ╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌ ┃
// ┃ This file is part of the Perspective library, distributed under the terms ┃
// ┃ of the [Apache License 2.0](https://www.apache.org/licenses/LICENSE-2.0). ┃
// ┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛
use std::collections::HashMap;
use std::pin::pin;
use std::str::FromStr;
use std::sync::Arc;
use futures::FutureExt;
use perspective_client::{
Client, ColumnWindow, DeleteOptions, OnUpdateData, OnUpdateMode, OnUpdateOptions, Table,
TableData, TableInitOptions, TableReadFormat, TableRef, UpdateData, UpdateOptions, View,
ViewWindow, assert_table_api, assert_view_api, asyncfn,
};
use pyo3::exceptions::PyValueError;
use pyo3::prelude::*;
use pyo3::types::{PyAny, PyBytes, PyDict, PyString};
use pythonize::depythonize;
use super::pandas::arrow_to_pandas;
use super::polars::arrow_to_polars;
use super::table_data::TableDataExt;
use super::update_data::UpdateDataExt;
use super::{pandas, polars, pyarrow};
use crate::py_async::{self, AllowThreads};
use crate::py_err::{PyPerspectiveError, ResultTClientErrorExt};
fn py_to_table_ref_async(val: &Bound<'_, PyAny>) -> PyResult<TableRef> {
if let Ok(t) = val.extract::<AsyncTable>() {
Ok(TableRef::from(t.table.as_ref()))
} else if let Ok(name) = val.extract::<String>() {
Ok(TableRef::from(name))
} else {
Err(pyo3::exceptions::PyTypeError::new_err(
"Expected a Table or string table name",
))
}
}
fn py_to_table_ref_from_owned(py: Python<'_>, val: &Py<PyAny>) -> PyResult<TableRef> {
let bound = val.bind(py);
py_to_table_ref_async(bound)
}
/// An instance of a [`Client`] is a connection to a single
/// `perspective_server::Server`, whether locally in-memory or remote over some
/// transport like a WebSocket.
///
/// `AsyncClient` and Perspective objects derived from it have _async_ APIs,
/// suitable for integration with a Python event loop like `asyncio`.
/// @private
#[pyclass(module = "perspective")]
#[derive(Clone)]
pub struct AsyncClient {
pub(crate) client: Client,
close_cb: Arc<Option<Py<PyAny>>>,
}
impl AsyncClient {
pub fn new_from_client(client: Client) -> Self {
AsyncClient {
client,
close_cb: Arc::default(),
}
}
}
#[pymethods]
impl AsyncClient {
#[new]
#[pyo3(signature=(handle_request, handle_close=None, name=None))]
pub fn new(
handle_request: Py<PyAny>,
handle_close: Option<Py<PyAny>>,
name: Option<String>,
) -> PyResult<Self> {
let handle_request = Arc::new(handle_request);
let client = Client::new_with_callback(
name.as_deref(),
asyncfn!(handle_request, async move |msg| {
if let Some(fut) = Python::with_gil(move |py| -> PyResult<_> {
let ret = handle_request.call1(py, (PyBytes::new(py, &msg),))?;
if isawaitable(ret.bind(py)).unwrap_or(false) {
Ok(Some(py_async::py_into_future(ret.into_bound(py))?))
} else {
Ok(None)
}
})? {
let result = fut.await;
Python::with_gil(|_| {
result
.map(|_| ())
.map_err(perspective_server::ServerError::from)
})?
}
Ok(())
}),
);
Ok(AsyncClient {
client: client.into_pyerr()?,
close_cb: handle_close.into(),
})
}
/// Handle a message from the external message queue.
/// [`Client::handle_response`] is part of the low-level message-handling
/// API necessary to implement new transports for a [`Client`]
/// connection to a local-or-remote `perspective_server::Server`, and
/// doesn't generally need to be called directly by "users" of a
/// [`Client`] once connected.
pub async fn handle_response(&self, bytes: Py<PyBytes>) -> PyResult<bool> {
self.client
.handle_response(Python::with_gil(|py| bytes.as_bytes(py)))
.await
.into_pyerr()
}
/// Creates a new [`Table`] from either a _schema_ or _data_.
///
/// The [`Client::table`] factory function can be initialized with either a
/// _schema_ (see [`Table::schema`]), or data in one of these formats:
///
/// - Apache Arrow
/// - CSV
/// - JSON row-oriented
/// - JSON column-oriented
///
/// When instantiated with _data_, the schema is inferred from this data.
/// While this is convenient, inferrence is sometimes imperfect e.g.
/// when the input is empty, null or ambiguous. For these cases,
/// [`Client::table`] can first be instantiated with a explicit schema.
///
/// When instantiated with a _schema_, the resulting [`Table`] is empty but
/// with known column names and column types. When subsqeuently
/// populated with [`Table::update`], these columns will be _coerced_ to
/// the schema's type. This behavior can be useful when
/// [`Client::table`]'s column type inferences doesn't work.
///
/// The resulting [`Table`] is _virtual_, and invoking its methods
/// dispatches events to the `perspective_server::Server` this
/// [`Client`] connects to, where the data is stored and all calculation
/// occurs.
///
/// # Arguments
///
/// - `arg` - Either _schema_ or initialization _data_.
/// - `options` - Optional configuration which provides one of:
/// - `limit` - The max number of rows the resulting [`Table`] can
/// store.
/// - `index` - The column name to use as an _index_ column. If this
/// `Table` is being instantiated by _data_, this column name must be
/// present in the data.
/// - `name` - The name of the table. This will be generated if it is
/// not provided.
/// - `format` - The explicit format of the input data, can be one of
/// `"json"`, `"columns"`, `"csv"` or `"arrow"`. This overrides
/// language-specific type dispatch behavior, which allows stringified
/// and byte array alternative inputs.
/// - `page_to_disk` - Back this [`Table`]'s canonical data with the
/// on-disk (memory-mapped) storage backend instead of memory.
///
/// # Python Examples
///
/// Load a CSV from a `str`:
///
/// ```python
/// table = await client.table("x,y\n1,2\n3,4")
/// ```
#[pyo3(signature=(input, limit=None, index=None, name=None, format=None, page_to_disk=None))]
pub async fn table(
&self,
input: Py<PyAny>,
limit: Option<u32>,
index: Option<Py<PyString>>,
name: Option<Py<PyString>>,
format: Option<Py<PyString>>,
page_to_disk: Option<bool>,
) -> PyResult<AsyncTable> {
let client = self.client.clone();
let py_client = Python::with_gil(|_| self.clone());
let table = Python::with_gil(|py| {
let mut options = TableInitOptions {
name: name.map(|x| x.extract::<String>(py)).transpose()?,
page_to_disk,
..TableInitOptions::default()
};
let format = TableReadFormat::parse(format.map(|x| x.to_string()))
.map_err(PyPerspectiveError::new_err)?;
match (limit, index) {
(None, None) => {},
(None, Some(index)) => {
options.index = Some(index.extract::<String>(py)?);
},
(Some(limit), None) => options.limit = Some(limit),
(Some(_), Some(_)) => {
Err(PyValueError::new_err("Cannot set both `limit` and `index`"))?
},
};
let input = input.into_bound(py);
let input_data = if pyarrow::is_arrow_table(py, &input)? {
pyarrow::to_arrow_bytes(py, &input)?.into_any()
} else if pandas::is_pandas_df(py, &input)? {
pandas::pandas_to_arrow_bytes(py, &input)?.into_any()
} else if polars::is_polars_df(py, &input)? || polars::is_polars_lf(py, &input)? {
polars::polars_to_arrow_bytes(py, &input)?.into_any()
} else {
input
};
let table_data = TableData::from_py(input_data, format)?;
let table = client.table(table_data, options);
Ok::<_, PyErr>(table)
})?;
let table = table.await.into_pyerr()?;
Ok(AsyncTable {
table: Arc::new(table),
client: py_client,
})
}
/// Opens a [`Table`] that is hosted on the `perspective_server::Server`
/// that is connected to this [`Client`].
///
/// The `name` property of [`TableInitOptions`] is used to identify each
/// [`Table`]. [`Table`] `name`s can be looked up for each [`Client`]
/// via [`Client::get_hosted_table_names`].
///
/// # Python Examples
///
/// ```python
/// table = await client.open_table("table_one");
/// ```
pub async fn open_table(&self, name: String) -> PyResult<AsyncTable> {
let client = self.client.clone();
let py_client = self.clone();
let table = client.open_table(name).await.into_pyerr()?;
Ok(AsyncTable {
table: Arc::new(table),
client: py_client,
})
}
/// Creates a new read-only [`Table`] by performing an INNER JOIN on two
/// source tables. The resulting table is reactive: when either source
/// table is updated, the join is automatically recomputed.
///
/// # Python Examples
///
/// ```python
/// joined = await client.join(orders_table, products_table, "Product ID", "left")
/// ```
#[pyo3(signature = (left, right, on, join_type=None, name=None, right_on=None))]
pub async fn join(
&self,
left: Py<PyAny>,
right: Py<PyAny>,
on: String,
join_type: Option<String>,
name: Option<String>,
right_on: Option<String>,
) -> PyResult<AsyncTable> {
let (left_ref, right_ref) = Python::with_gil(|py| {
let left_ref = py_to_table_ref_from_owned(py, &left)?;
let right_ref = py_to_table_ref_from_owned(py, &right)?;
Ok::<_, PyErr>((left_ref, right_ref))
})?;
let jt = super::client_sync::parse_join_type(join_type.as_deref())?;
let options = perspective_client::JoinOptions {
join_type: Some(jt),
name,
right_on,
};
let py_client = self.clone();
let table = self
.client
.join(left_ref, right_ref, &on, options)
.await
.into_pyerr()?;
Ok(AsyncTable {
table: Arc::new(table),
client: py_client,
})
}
/// Retrieves the names of all tables that this client has access to.
///
/// `name` is a string identifier unique to the [`Table`] (per [`Client`]),
/// which can be used in conjunction with [`Client::open_table`] to get
/// a [`Table`] instance without the use of [`Client::table`]
/// constructor directly (e.g., one created by another [`Client`]).
///
/// # Python Examples
///
/// ```python
/// tables = await client.get_hosted_table_names();
/// ```
pub async fn get_hosted_table_names(&self) -> PyResult<Vec<String>> {
self.client.get_hosted_table_names().await.into_pyerr()
}
/// Register a callback which is invoked whenever [`Client::table`] (on this
/// [`Client`]) or [`Table::delete`] (on a [`Table`] belinging to this
/// [`Client`]) are called.
pub async fn on_hosted_tables_update(&self, callback_py: Py<PyAny>) -> PyResult<u32> {
let callback = Box::new(move || {
let callback = Python::with_gil(|py| Py::clone_ref(&callback_py, py));
async move {
let aggregate_errors: PyResult<()> = {
let callback = Python::with_gil(|py| Py::clone_ref(&callback, py));
Python::with_gil(|py| {
callback.call0(py)?;
Ok(())
})
};
// TODO These are unrecoverable errors - we should mark them as such
if let Err(err) = aggregate_errors {
tracing::warn!("Error in on_hosted_tables_update callback: {:?}", err);
}
}
.boxed()
});
let callback_id = self
.client
.on_hosted_tables_update(callback)
.await
.into_pyerr()?;
Ok(callback_id)
}
/// Remove a callback previously registered via
/// [`Client::on_hosted_tables_update`].
pub async fn remove_hosted_tables_update(&self, id: u32) -> PyResult<()> {
self.client
.remove_hosted_tables_update(id)
.await
.into_pyerr()
}
/// Provides the [`SystemInfo`] struct, implementation-specific metadata
/// about the [`perspective_server::Server`] runtime such as Memory and
/// CPU usage.
pub async fn system_info(&self) -> PyResult<Py<PyAny>> {
let sysinfo = self.client.system_info().await.into_pyerr()?;
Python::with_gil(|py| Ok(pythonize::pythonize(py, &sysinfo)?.unbind()))
}
/// Terminates this [`Client`], cleaning up any [`crate::View`] handles the
/// [`Client`] has open as well as its callbacks.
pub fn terminate(&self, py: Python<'_>) -> PyResult<()> {
if let Some(cb) = &*self.close_cb {
cb.call0(py)?;
}
Ok(())
}
}
/// [`AsyncTable`] is Perspective's columnar data frame, analogous to a
/// Pandas/Polars `DataFrame` or Apache Arrow, supporting append & in-place
/// updates, removal by index, and update notifications.
///
/// A [`AsyncTable`] contains columns, each of which have a unique name, are
/// strongly and consistently typed, and contains rows of data conforming to the
/// column's type. Each column in a [`AsyncTable`] must have the same number of
/// rows, though not every row must contain data; null-values are used to
/// indicate missing values in the dataset. The schema of a [`AsyncTable`] is
/// _immutable after creation_, which means the column names and data types
/// cannot be changed after the [`AsyncTable`] has been created. Columns cannot
/// be added or deleted after creation either, but a [`AsyncView`] can be used
/// to select an arbitrary set of columns from the [`AsyncTable`].
#[pyclass]
#[derive(Clone)]
pub struct AsyncTable {
pub(super) table: Arc<Table>,
pub(super) client: AsyncClient,
}
assert_table_api!(AsyncTable);
#[pymethods]
impl AsyncTable {
pub fn get_index(&self) -> Option<String> {
self.table.get_index()
}
/// Get a copy of the [`Client`] this [`Table`] came from.
pub async fn get_client(&self) -> AsyncClient {
AsyncClient {
client: self.table.get_client(),
close_cb: self.client.close_cb.clone(),
}
}
/// Returns the user-specified row limit for this table.
pub fn get_limit(&self) -> Option<u32> {
self.table.get_limit()
}
/// Returns the user-specified name for this table, or the auto-generated
/// name if a name was not specified when the table was created.
pub fn get_name(&self) -> String {
self.table.get_name().into()
}
/// Returns the number of rows in a [`Table`].
pub async fn size(&self) -> PyResult<usize> {
self.table.size().await.into_pyerr()
}
/// Returns the column names of this [`Table`] in "natural" order (the
/// ordering implied by the input format).
///
/// # Python Examples
///
/// ```python
/// columns = table.columns()
/// ```
pub async fn columns(&self) -> PyResult<Vec<String>> {
self.table.columns().await.into_pyerr()
}
/// Removes all the rows in the [`Table`], but preserves everything else
/// including the schema, index, and any callbacks or registered
/// [`View`] instances.
///
/// Calling [`Table::clear`], like [`Table::update`] and [`Table::remove`],
/// will trigger an update event to any registered listeners via
/// [`View::on_update`].
pub async fn clear(&self) -> PyResult<()> {
self.table.clear().await.into_pyerr()
}
/// Delete this [`Table`] and cleans up associated resources.
///
/// [`Table`]s do not stop consuming resources or processing updates when
/// they are garbage collected in their host language - you must call
/// this method to reclaim these.
///
/// # Arguments
///
/// - `options` An options dictionary.
/// - `lazy` Whether to delete this [`Table`] _lazily_. When false (the
/// default), the delete will occur immediately, assuming it has no
/// [`View`] instances registered to it (which must be deleted first,
/// otherwise this method will throw an error). When true, the
/// [`Table`] will only be marked for deltion once its [`View`]
/// dependency count reaches 0.
///
/// # Python Examples
///
/// ```python
/// table = await client.table("x,y\n1,2\n3,4")
///
/// # ...
///
/// table.delete(lazy=True)
/// ```
#[pyo3(signature=(lazy=false))]
pub async fn delete(&self, lazy: bool) -> PyResult<()> {
self.table.delete(DeleteOptions { lazy }).await.into_pyerr()
}
/// Create a unique channel ID on this [`Table`], which allows
/// `View::on_update` callback calls to be associated with the
/// `Table::update` which caused them.
pub async fn make_port(&self) -> PyResult<i32> {
self.table.make_port().await.into_pyerr()
}
/// Register a callback which is called exactly once, when this [`Table`] is
/// deleted with the [`Table::delete`] method.
///
/// [`Table::on_delete`] resolves when the subscription message is sent, not
/// when the _delete_ event occurs.
pub async fn on_delete(&self, callback_py: Py<PyAny>) -> PyResult<u32> {
let callback = {
let callback_py = Python::with_gil(|py| Py::clone_ref(&callback_py, py));
Box::new(move || {
Python::with_gil(|py| callback_py.call0(py))
.expect("`on_delete()` callback failed");
})
};
let callback_id = self.table.on_delete(callback).await.into_pyerr()?;
Ok(callback_id)
}
/// Removes a listener with a given ID, as returned by a previous call to
/// [`Table::on_delete`].
pub async fn remove_delete(&self, callback_id: u32) -> PyResult<()> {
self.table.remove_delete(callback_id).await.into_pyerr()
}
/// Removes rows from this [`Table`] with the `index` column values
/// supplied.
///
/// # Arguments
///
/// - `indices` - A list of `index` column values for rows that should be
/// removed.
///
/// # Python Examples
///
/// ```python
/// tbl = await client.table({"a": [1, 2, 3]}, index="a")
/// await tbl.remove([2, 3])
/// ```
#[pyo3(signature=(input, format=None))]
pub async fn remove(&self, input: Py<PyAny>, format: Option<String>) -> PyResult<()> {
let table = &self.table;
let format = TableReadFormat::parse(format).map_err(PyPerspectiveError::new_err)?;
let table_data = Python::with_gil(|py| UpdateData::from_py(input.into_bound(py), format))?;
table.remove(table_data).await.into_pyerr()
}
/// Replace all rows in this [`Table`] with the input data, coerced to this
/// [`Table`]'s existing [`Schema`], notifying any derived [`View`] and
/// [`View::on_update`] callbacks.
///
/// Calling [`Table::replace`] is an easy way to replace _all_ the data in a
/// [`Table`] without losing any derived [`View`] instances or
/// [`View::on_update`] callbacks. [`Table::replace`] does _not_ infer
/// data types like [`Client::table`] does, rather it _coerces_ input
/// data to the `Schema` like [`Table::update`]. If you need a [`Table`]
/// with a different `Schema`, you must create a new one.
///
/// # Python Examples
///
/// ```python
/// await table.replace("x,y\n1,2")
/// ```
#[pyo3(signature=(input, format=None))]
pub async fn replace(&self, input: Py<PyAny>, format: Option<String>) -> PyResult<()> {
let table = &self.table;
let format = TableReadFormat::parse(format).map_err(PyPerspectiveError::new_err)?;
let table_data = Python::with_gil(|py| UpdateData::from_py(input.into_bound(py), format))?;
table.replace(table_data).await.into_pyerr()
}
/// Updates the rows of this table and any derived [`View`] instances.
///
/// Calling [`Table::update`] will trigger the [`View::on_update`] callbacks
/// register to derived [`View`], and the call itself will not resolve until
/// _all_ derived [`View`]'s are notified.
///
/// When updating a [`Table`] with an `index`, [`Table::update`] supports
/// partial updates, by omitting columns from the update data.
///
/// # Arguments
///
/// - `input` - The input data for this [`Table`]. The schema of a [`Table`]
/// is immutable after creation, so this method cannot be called with a
/// schema.
/// - `options` - Options for this update step - see [`UpdateOptions`].
///
/// # Python Examples
///
/// ```python
/// await table.update("x,y\n1,2")
/// ```
#[pyo3(signature=(input, port_id=None, format=None))]
pub async fn update(
&self,
input: Py<PyAny>,
port_id: Option<u32>,
format: Option<String>,
) -> PyResult<()> {
let input_data: Py<PyAny> = Python::with_gil(|py| {
let input = input.into_bound(py);
let data = if pyarrow::is_arrow_table(py, &input)? {
pyarrow::to_arrow_bytes(py, &input)?.into_any()
} else if pandas::is_pandas_df(py, &input)? {
pandas::pandas_to_arrow_bytes(py, &input)?.into_any()
} else if polars::is_polars_df(py, &input)? || polars::is_polars_lf(py, &input)? {
polars::polars_to_arrow_bytes(py, &input)?.into_any()
} else {
input
};
Ok(data.unbind()) as PyResult<Py<PyAny>>
})?;
let table = &self.table;
let format = TableReadFormat::parse(format).map_err(PyPerspectiveError::new_err)?;
let table_data =
Python::with_gil(|py| UpdateData::from_py(input_data.into_bound(py), format))?;
let options = UpdateOptions { port_id, format };
AllowThreads(pin!(table.update(table_data, options)))
.await
.into_pyerr()?;
Ok(())
}
/// Validates the given expressions.
pub async fn validate_expressions(&self, expressions: Py<PyAny>) -> PyResult<Py<PyAny>> {
let expressions = Python::with_gil(|py| depythonize(expressions.bind(py)))?;
let records = self
.table
.validate_expressions(expressions)
.await
.into_pyerr()?;
Python::with_gil(|py| Ok(pythonize::pythonize(py, &records)?.unbind()))
}
/// Returns a table's [`Schema`], a mapping of column names to column types.
///
/// The mapping of a [`Table`]'s column names to data types is referred to
/// as a [`Schema`]. Each column has a unique name and a data type, one
/// of:
///
/// - `"boolean"` - A boolean type
/// - `"date"` - A timesonze-agnostic date type (month/day/year)
/// - `"datetime"` - A millisecond-precision datetime type in the UTC
/// timezone
/// - `"float"` - A 64 bit float
/// - `"integer"` - A signed 32 bit integer (the integer type supported by
/// JavaScript)
/// - `"string"` - A `String` data type (encoded internally as a
/// _dictionary_)
///
/// Note that all [`Table`] columns are _nullable_, regardless of the data
/// type.
pub async fn schema(&self) -> PyResult<HashMap<String, String>> {
let schema = self.table.schema().await.into_pyerr()?;
Ok(schema
.into_iter()
.map(|(x, y)| (x, format!("{y}")))
.collect())
}
/// Create a new [`View`] from this table with a specified
/// [`ViewConfigUpdate`].
///
/// See [`View`] struct.
///
/// # Python Examples
///
/// ```python
/// view = await table.view(
/// columns=["Sales"],
/// aggregates={"Sales": "sum"},
/// group_by=["Region", "Country"],
/// filter=[["Category", "in", ["Furniture", "Technology"]]]
/// )
/// ```
#[pyo3(signature = (**kwargs))]
pub async fn view(&self, kwargs: Option<Py<PyDict>>) -> PyResult<AsyncView> {
let config = kwargs
.map(|config| Python::with_gil(|py| depythonize(config.bind(py))))
.transpose()?;
let view = self.table.view(config).await.into_pyerr()?;
Ok(AsyncView {
view: Arc::new(view),
_client: self.client.clone(),
})
}
}
/// The [`View`] struct is Perspective's query and serialization interface. It
/// represents a query on the `Table`'s dataset and is always created from an
/// existing `Table` instance via the [`Table::view`] method.
///
/// [`View`]s are immutable with respect to the arguments provided to the
/// [`Table::view`] method; to change these parameters, you must create a new
/// [`View`] on the same [`Table`]. However, each [`View`] is _live_ with
/// respect to the [`Table`]'s data, and will (within a conflation window)
/// update with the latest state as its parent [`Table`] updates, including
/// incrementally recalculating all aggregates, pivots, filters, etc. [`View`]
/// query parameters are composable, in that each parameter works independently
/// _and_ in conjunction with each other, and there is no limit to the number of
/// pivots, filters, etc. which can be applied.
#[pyclass]
#[derive(Clone)]
pub struct AsyncView {
pub(crate) view: Arc<View>,
_client: AsyncClient,
}
assert_view_api!(AsyncView);
#[pymethods]
impl AsyncView {
/// Returns an array of strings containing the column paths of the [`View`]
/// without any of the source columns.
///
/// A column path shows the columns that a given cell belongs to after
/// pivots are applied.
pub async fn column_paths(&self, window: Option<Py<PyDict>>) -> PyResult<Vec<String>> {
let window: ColumnWindow = Python::with_gil(|py| window.map(|x| depythonize(x.bind(py))))
.transpose()?
.unwrap_or_default();
self.view.column_paths(window).await.into_pyerr()
}
/// Delete this [`View`] and clean up all resources associated with it.
/// [`View`] objects do not stop consuming resources or processing
/// updates when they are garbage collected - you must call this method
/// to reclaim these.
pub async fn delete(&self) -> PyResult<()> {
self.view.delete().await.into_pyerr()
}
/// Returns this [`View`]'s _dimensions_, row and column count, as well as
/// those of the [`crate::Table`] from which it was derived.
///
/// - `num_table_rows` - The number of rows in the underlying
/// [`crate::Table`].
/// - `num_table_columns` - The number of columns in the underlying
/// [`crate::Table`] (including the `index` column if this
/// [`crate::Table`] was constructed with one).
/// - `num_view_rows` - The number of rows in this [`View`]. If this
/// [`View`] has a `group_by` clause, `num_view_rows` will also include
/// aggregated rows.
/// - `num_view_columns` - The number of columns in this [`View`]. If this
/// [`View`] has a `split_by` clause, `num_view_columns` will include all
/// _column paths_, e.g. the number of `columns` clause times the number
/// of `split_by` groups.
pub async fn dimensions(&self) -> PyResult<Py<PyAny>> {
let dim = self.view.dimensions().await.into_pyerr()?;
Python::with_gil(|py| Ok(pythonize::pythonize(py, &dim)?.unbind()))
}
pub async fn expand(&self, index: u32) -> PyResult<u32> {
self.view.expand(index).await.into_pyerr()
}
pub async fn collapse(&self, index: u32) -> PyResult<u32> {
self.view.collapse(index).await.into_pyerr()
}
/// The expression schema of this [`View`], which contains only the
/// expressions created on this [`View`]. See [`View::schema`] for
/// details.
pub async fn expression_schema(&self) -> PyResult<HashMap<String, String>> {
Ok(self
.view
.expression_schema()
.await
.into_pyerr()?
.into_iter()
.map(|(k, v)| (k, format!("{v}")))
.collect())
}
/// A copy of the config object passed to the [`Table::view`] method which
/// created this [`View`].
pub async fn get_config(&self) -> PyResult<Py<PyAny>> {
let config = self.view.get_config().await.into_pyerr()?;
Python::with_gil(|py| Ok(pythonize::pythonize(py, &config)?.unbind()))
}
/// Calculates the [min, max] of the leaf nodes of a column `column_name`.
///
/// # Returns
///
/// A tuple of [min, max], whose types are column and aggregate dependent.
pub async fn get_min_max(&self, name: String) -> PyResult<(PyObject, PyObject)> {
let (min, max) = self.view.get_min_max(name).await.into_pyerr()?;
Python::with_gil(|py| {
Ok((
super::client_sync::scalar_to_py(py, &min),
super::client_sync::scalar_to_py(py, &max),
))
})
}
/// The number of aggregated rows in this [`View`]. This is affected by the
/// "group_by" configuration parameter supplied to this view's contructor.
///
/// # Returns
///
/// The number of aggregated rows.
pub async fn num_rows(&self) -> PyResult<u32> {
self.view.num_rows().await.into_pyerr()
}
/// The number of aggregated columns in this [`View`]. This is affected by
/// the "split_by" configuration parameter supplied to this view's
/// contructor.
///
/// # Returns
///
/// The number of aggregated columns.
pub async fn num_columns(&self) -> PyResult<u32> {
let dim = self.view.dimensions().await.into_pyerr()?;
Ok(dim.num_view_columns)
}
/// The schema of this [`View`].
///
/// The [`View`] schema differs from the `schema` returned by
/// [`Table::schema`]; it may have different column names due to
/// `expressions` or `columns` configs, or it maye have _different
/// column types_ due to the application og `group_by` and `aggregates`
/// config. You can think of [`Table::schema`] as the _input_ schema and
/// [`View::schema`] as the _output_ schema of a Perspective pipeline.
pub async fn schema(&self) -> PyResult<HashMap<String, String>> {
Ok(self
.view
.schema()
.await
.into_pyerr()?
.into_iter()
.map(|(k, v)| (k, format!("{v}")))
.collect())
}
/// Register a callback with this [`View`]. Whenever the [`View`] is
/// deleted, this callback will be invoked.
pub async fn on_delete(&self, callback_py: Py<PyAny>) -> PyResult<u32> {
let callback = {
let callback_py = Arc::new(callback_py);
Box::new(move || {
Python::with_gil(|py| callback_py.call0(py))
.expect("`on_delete()` callback failed");
})
};
let callback_id = self.view.on_delete(callback).await.into_pyerr()?;
Ok(callback_id)
}
/// Unregister a previously registered [`View::on_delete`] callback.
pub async fn remove_delete(&self, callback_id: u32) -> PyResult<()> {
self.view.remove_delete(callback_id).await.into_pyerr()
}
/// Register a callback with this [`View`]. Whenever the view's underlying
/// table emits an update, this callback will be invoked with an object
/// containing `port_id`, indicating which port the update fired on, and
/// optionally `delta`, which is the new data that was updated for each
/// cell or each row.
///
/// # Arguments
///
/// - `on_update` - A callback function invoked on update, which receives an
/// object with two keys: `port_id`, indicating which port the update was
/// triggered on, and `delta`, whose value is dependent on the mode
/// parameter.
/// - `options` - If this is provided as `OnUpdateOptions { mode:
/// Some(OnUpdateMode::Row) }`, then `delta` is an Arrow of the updated
/// rows. Otherwise `delta` will be [`Option::None`].
#[pyo3(signature=(callback, mode=None))]
pub async fn on_update(&self, callback: Py<PyAny>, mode: Option<String>) -> PyResult<u32> {
let callback = move |x: OnUpdateData| {
let callback = Python::with_gil(|py| Py::clone_ref(&callback, py));
async move {
let aggregate_errors: PyResult<()> = {
let callback = Python::with_gil(|py| Py::clone_ref(&callback, py));
Python::with_gil(|py| {
match &x.delta {
None => callback.call1(py, (x.port_id,))?,
Some(delta) => {
callback.call1(py, (x.port_id, PyBytes::new(py, delta)))?
},
};
Ok(())
})
};
if let Err(err) = aggregate_errors {
tracing::warn!("Error in on_update callback: {:?}", err);
}
}
.boxed()
};
let mode = mode
.map(|x| OnUpdateMode::from_str(x.as_str()))
.transpose()
.into_pyerr()?;
self.view
.on_update(Box::new(callback), OnUpdateOptions { mode })
.await
.into_pyerr()
}
/// Unregister a previously registered update callback with this [`View`].
///
/// # Arguments
///
/// - `id` - A callback `id` as returned by a recipricol call to
/// [`View::on_update`].
pub async fn remove_update(&self, callback_id: u32) -> PyResult<()> {
self.view.remove_update(callback_id).await.into_pyerr()
}
#[pyo3(signature=(**window))]
pub async fn to_dataframe(&self, window: Option<Py<PyDict>>) -> PyResult<Py<PyAny>> {
let window: ViewWindow = Python::with_gil(|py| window.map(|x| depythonize(x.bind(py))))
.transpose()?
.unwrap_or_default();
let arrow = self.view.to_arrow(window).await.into_pyerr()?;
Python::with_gil(|py| arrow_to_pandas(py, &arrow))
}
#[pyo3(signature=(**window))]
pub async fn to_polars(&self, window: Option<Py<PyDict>>) -> PyResult<Py<PyAny>> {
let window: ViewWindow = Python::with_gil(|py| window.map(|x| depythonize(x.bind(py))))
.transpose()?
.unwrap_or_default();
let arrow = self.view.to_arrow(window).await.into_pyerr()?;
Python::with_gil(|py| arrow_to_polars(py, &arrow))
}
/// Serializes a [`View`] to the Apache Arrow data format.
#[pyo3(signature=(**window))]
pub async fn to_arrow(&self, window: Option<Py<PyDict>>) -> PyResult<Py<PyBytes>> {
let window: ViewWindow = Python::with_gil(|py| window.map(|x| depythonize(x.bind(py))))
.transpose()?
.unwrap_or_default();
let arrow = self.view.to_arrow(window).await.into_pyerr()?;
Ok(Python::with_gil(|py| PyBytes::new(py, &arrow).into()))
}
/// Serializes this [`View`] to CSV data in a standard format.
#[pyo3(signature=(**window))]
pub async fn to_csv(&self, window: Option<Py<PyDict>>) -> PyResult<String> {
let window: ViewWindow = Python::with_gil(|py| window.map(|x| depythonize(x.bind(py))))
.transpose()?
.unwrap_or_default();
self.view.to_csv(window).await.into_pyerr()
}
/// Serializes this [`View`] to a string of JSON data. Useful if you want to
/// save additional round trip serialize/deserialize cycles.
#[pyo3(signature=(**window))]
pub async fn to_columns_string(&self, window: Option<Py<PyDict>>) -> PyResult<String> {
let window: ViewWindow = Python::with_gil(|py| window.map(|x| depythonize(x.bind(py))))
.transpose()?
.unwrap_or_default();
self.view.to_columns_string(window).await.into_pyerr()
}
/// Serializes this [`View`] to Python objects in a column-oriented
/// format.
#[pyo3(signature = (**window))]
pub async fn to_columns(&self, window: Option<Py<PyDict>>) -> PyResult<Py<PyAny>> {
let json = self.to_columns_string(window).await?;
Python::with_gil(|py| {
let json_module = PyModule::import(py, "json")?;
let records = json_module.call_method1("loads", (json,))?;
Ok(records.unbind())
})
}
/// Render this `View` as a JSON string.
#[pyo3(signature=(window=None))]
pub async fn to_json_string(&self, window: Option<Py<PyDict>>) -> PyResult<String> {
let window: ViewWindow = Python::with_gil(|py| window.map(|x| depythonize(x.bind(py))))
.transpose()?
.unwrap_or_default();
self.view.to_json_string(window).await.into_pyerr()
}
/// Renders this [`View`] as an [NDJSON](https://github.com/ndjson/ndjson-spec)
/// formatted `String`.
#[pyo3(signature=(window=None))]
pub async fn to_ndjson(&self, window: Option<Py<PyDict>>) -> PyResult<String> {
let window: ViewWindow = Python::with_gil(|py| window.map(|x| depythonize(x.bind(py))))
.transpose()?
.unwrap_or_default();
self.view.to_ndjson(window).await.into_pyerr()
}
/// Alias for [`View::to_json`].
#[pyo3(signature = (**window))]
pub async fn to_records(&self, window: Option<Py<PyDict>>) -> PyResult<Py<PyAny>> {
let json = self.to_json_string(window).await?;
Python::with_gil(|py| {
let json_module = PyModule::import(py, "json")?;
let records = json_module.call_method1("loads", (json,))?;
Ok(records.unbind())
})
}
/// Serializes this [`View`] to Python objects in a row-oriented
/// format.
#[pyo3(signature = (**window))]
pub async fn to_json(&self, window: Option<Py<PyDict>>) -> PyResult<Py<PyAny>> {
self.to_records(window).await
}
}
fn isawaitable(object: &Bound<'_, PyAny>) -> PyResult<bool> {
let py = object.py();
py.import("inspect")?
.call_method1("isawaitable", (object,))?
.extract()
}