perspective-js 3.7.1-alpha1

A data visualization and analytics component, especially well-suited for large and/or streaming datasets.
Documentation
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
// ┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓
// ┃ ██████ ██████ ██████       █      █      █      █      █ █▄  ▀███ █       ┃
// ┃ ▄▄▄▄▄█ █▄▄▄▄▄ ▄▄▄▄▄█  ▀▀▀▀▀█▀▀▀▀▀ █ ▀▀▀▀▀█ ████████▌▐███ ███▄  ▀█ █ ▀▀▀▀▀ ┃
// ┃ █▀▀▀▀▀ █▀▀▀▀▀ █▀██▀▀ ▄▄▄▄▄ █ ▄▄▄▄▄█ ▄▄▄▄▄█ ████████▌▐███ █████▄   █ ▄▄▄▄▄ ┃
// ┃ █      ██████ █  ▀█▄       █ ██████      █      ███▌▐███ ███████▄ █       ┃
// ┣━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┫
// ┃ 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::error::Error;
use std::future::Future;
use std::sync::Arc;

use derivative::Derivative;
use futures::channel::oneshot;
use js_sys::{Function, Uint8Array};
#[cfg(doc)]
use perspective_client::SystemInfo;
use perspective_client::{
    ClientError, ReconnectCallback, Session, TableData, TableInitOptions, asyncfn,
};
use wasm_bindgen::prelude::*;
use wasm_bindgen_derive::TryFromJsValue;
use wasm_bindgen_futures::{JsFuture, future_to_promise};

pub use crate::table::*;
use crate::utils::{ApiError, ApiResult, JsValueSerdeExt, LocalPollLoop};
use crate::{TableDataExt, apierror};

#[wasm_bindgen]
extern "C" {
    #[derive(Clone)]
    #[wasm_bindgen(typescript_type = "TableInitOptions")]
    pub type JsTableInitOptions;
}

#[wasm_bindgen]
#[derive(Clone)]
pub struct ProxySession(perspective_client::ProxySession);

#[wasm_bindgen]
impl ProxySession {
    #[wasm_bindgen(constructor)]
    pub fn new(client: &Client, on_response: &Function) -> Self {
        let poll_loop = LocalPollLoop::new({
            let on_response = on_response.clone();
            move |msg: Vec<u8>| {
                let msg = Uint8Array::from(&msg[..]);
                on_response.call1(&JsValue::UNDEFINED, &JsValue::from(msg))?;
                Ok(JsValue::null())
            }
        });
        // NB: This swallows any errors raised by the inner callback
        let on_response = Box::new(move |msg: &[u8]| {
            wasm_bindgen_futures::spawn_local(poll_loop.poll(msg.to_vec()));
            Ok(())
        });
        Self(perspective_client::ProxySession::new(
            client.client.clone(),
            on_response,
        ))
    }

    #[wasm_bindgen]
    pub async fn handle_request(&self, value: JsValue) -> ApiResult<()> {
        let uint8array = Uint8Array::new(&value);
        let slice = uint8array.to_vec();
        self.0.handle_request(&slice).await?;
        Ok(())
    }

    pub async fn close(self) {
        self.0.close().await;
    }
}

/// An instance of a [`Client`] is a unique connection to a single
/// `perspective_server::Server`, whether locally in-memory or remote over some
/// transport like a WebSocket.
///
/// The browser and node.js libraries both support the `websocket(url)`
/// constructor, which connects to a remote `perspective_server::Server`
/// instance over a WebSocket transport.
///
/// In the browser, the `worker()` constructor creates a new Web Worker
/// `perspective_server::Server` and returns a [`Client`] connected to it.
///
/// In node.js, a pre-instantied [`Client`] connected synhronously to a global
/// singleton `perspective_server::Server` is the default module export.
///
/// # JavaScript Examples
///
/// Create a Web Worker `perspective_server::Server` in the browser and return a
/// [`Client`] instance connected for it:
///
/// ```javascript
/// import perspective from "@finos/perspective";
/// const client = await perspective.worker();
/// ```
///
/// Create a WebSocket connection to a remote `perspective_server::Server`:
///
/// ```javascript
/// import perspective from "@finos/perspective";
/// const client = await perspective.websocket("ws://locahost:8080/ws");
/// ```
///
/// Access the synchronous client in node.js:
///
/// ```javascript
/// import { default as client } from "@finos/perspective";
/// ```
#[wasm_bindgen]
#[derive(TryFromJsValue, Clone)]
pub struct Client {
    pub(crate) close: Option<Function>,
    pub(crate) client: perspective_client::Client,
}

impl PartialEq for Client {
    fn eq(&self, other: &Self) -> bool {
        self.client.get_name() == other.client.get_name()
    }
}

/// A wrapper around [`js_sys::Function`] to ease async integration for the
/// `reconnect` argument of [`Client::on_error`] callback.
#[derive(Derivative)]
#[derivative(Clone(bound = ""))]
struct JsReconnect<I>(Arc<dyn Fn(I) -> js_sys::Promise>);

unsafe impl<I> Send for JsReconnect<I> {}
unsafe impl<I> Sync for JsReconnect<I> {}

impl<I> JsReconnect<I> {
    fn run(&self, args: I) -> js_sys::Promise {
        self.0(args)
    }

    fn run_all(
        &self,
        args: I,
    ) -> impl Future<Output = Result<(), Box<dyn Error + Send + Sync + 'static>>>
    + Send
    + Sync
    + 'static
    + use<I> {
        let (sender, receiver) = oneshot::channel::<Result<(), Box<dyn Error + Send + Sync>>>();
        let p = self.0(args);
        let _ = future_to_promise(async move {
            let result = JsFuture::from(p)
                .await
                .map(|_| ())
                .map_err(|x| format!("{:?}", x).into());

            sender.send(result).unwrap();
            Ok(JsValue::UNDEFINED)
        });

        async move { receiver.await.unwrap() }
    }
}

impl<F, I> From<F> for JsReconnect<I>
where
    F: Fn(I) -> js_sys::Promise + 'static,
{
    fn from(value: F) -> Self {
        JsReconnect(Arc::new(value))
    }
}

impl Client {
    pub fn get_client(&self) -> &'_ perspective_client::Client {
        &self.client
    }
}

#[wasm_bindgen]
impl Client {
    #[wasm_bindgen(constructor)]
    pub fn new(send_request: Function, close: Option<Function>) -> ApiResult<Self> {
        let send_request = JsReconnect::from(move |mut v: Vec<u8>| {
            let buff2 = unsafe { js_sys::Uint8Array::view_mut_raw(v.as_mut_ptr(), v.len()) };
            send_request
                .call1(&JsValue::UNDEFINED, &buff2)
                .unwrap()
                .unchecked_into::<js_sys::Promise>()
        });

        let client = perspective_client::Client::new_with_callback(None, move |msg| {
            send_request.run_all(msg)
        })?;

        Ok(Client { close, client })
    }

    #[wasm_bindgen]
    pub fn new_proxy_session(&self, on_response: &Function) -> ProxySession {
        ProxySession::new(self, on_response)
    }

    #[wasm_bindgen]
    pub async fn init(&self) -> ApiResult<()> {
        self.client.clone().init().await?;
        Ok(())
    }

    #[wasm_bindgen]
    pub async fn handle_response(&self, value: &JsValue) -> ApiResult<()> {
        let uint8array = Uint8Array::new(value);
        let slice = uint8array.to_vec();
        self.client.handle_response(&slice).await?;
        Ok(())
    }

    #[wasm_bindgen]
    pub async fn handle_error(&self, error: String, reconnect: Option<Function>) -> ApiResult<()> {
        self.client
            .handle_error(
                ClientError::Unknown(error),
                reconnect.map(|reconnect| {
                    let reconnect =
                        JsReconnect::from(move |()| match reconnect.call0(&JsValue::UNDEFINED) {
                            Ok(x) => x.unchecked_into::<js_sys::Promise>(),
                            Err(e) => {
                                // This error may occur when _invoking_ the function
                                tracing::warn!("{:?}", e);
                                js_sys::Promise::reject(&format!("C {:?}", e).into())
                            },
                        });

                    asyncfn!(reconnect, async move || {
                        if let Err(e) = JsFuture::from(reconnect.run(())).await {
                            if let Some(e) = e.dyn_ref::<js_sys::Object>() {
                                Err(ClientError::Unknown(e.to_string().as_string().unwrap()))
                            } else {
                                Err(ClientError::Unknown(e.as_string().unwrap()))
                            }
                        } else {
                            Ok(())
                        }
                    })
                }),
            )
            .await?;

        Ok(())
    }

    #[wasm_bindgen]
    pub async fn on_error(&self, callback: Function) -> ApiResult<u32> {
        let callback = JsReconnect::from(
            move |(message, reconnect): (ClientError, Option<ReconnectCallback>)| {
                let cl: Closure<dyn Fn() -> js_sys::Promise> = Closure::new(move || {
                    let reconnect = reconnect.clone();
                    future_to_promise(async move {
                        if let Some(f) = reconnect {
                            f().await.map_err(|e| JsValue::from(format!("A {}", e)))?;
                        }

                        Ok(JsValue::UNDEFINED)
                    })
                });

                if let Err(e) = callback.call2(
                    &JsValue::UNDEFINED,
                    &JsValue::from(apierror!(ClientError(message))),
                    &cl.into_js_value(),
                ) {
                    tracing::warn!("{:?}", e);
                }

                js_sys::Promise::resolve(&JsValue::UNDEFINED)
            },
        );

        let poll_loop = LocalPollLoop::new_async(move |x| JsFuture::from(callback.run(x)));
        let id = self
            .client
            .on_error(asyncfn!(poll_loop, async move |message, reconnect| {
                poll_loop.poll((message, reconnect)).await;
                Ok(())
            }))
            .await?;

        Ok(id)
    }

    /// 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.
    ///
    /// # JavaScript Examples
    ///
    /// Load a CSV from a `string`:
    ///
    /// ```javascript
    /// const table = await client.table("x,y\n1,2\n3,4");
    /// ```
    ///
    /// Load an Arrow from an `ArrayBuffer`:
    ///
    /// ```javascript
    /// import * as fs from "node:fs/promises";
    /// const table2 = await client.table(await fs.readFile("superstore.arrow"));
    /// ```
    ///
    /// Load a CSV from a `UInt8Array` (the default for this type is Arrow)
    /// using a format override:
    ///
    /// ```javascript
    /// const enc = new TextEncoder();
    /// const table = await client.table(enc.encode("x,y\n1,2\n3,4"), {
    ///     format: "csv",
    /// });
    /// ```
    ///
    /// Create a table with an `index`:
    ///
    /// ```javascript
    /// const table = await client.table(data, { index: "Row ID" });
    /// ```
    #[wasm_bindgen]
    pub async fn table(
        &self,
        value: &JsTableInitData,
        options: Option<JsTableInitOptions>,
    ) -> ApiResult<Table> {
        let options = options
            .into_serde_ext::<Option<TableInitOptions>>()?
            .unwrap_or_default();

        let args = TableData::from_js_value(value, options.format)?;
        Ok(Table(self.client.table(args, options).await?))
    }

    /// Terminates this [`Client`], cleaning up any [`crate::View`] handles the
    /// [`Client`] has open as well as its callbacks.
    #[wasm_bindgen]
    pub fn terminate(&self) -> ApiResult<JsValue> {
        if let Some(f) = self.close.clone() {
            Ok(f.call0(&JsValue::UNDEFINED)?)
        } else {
            Err(ApiError::new("Client type cannot be terminated"))
        }
    }

    /// 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`].
    ///
    /// # JavaScript Examples
    ///
    /// Get a virtual [`Table`] named "table_one" from this [`Client`]
    ///
    /// ```javascript
    /// const tables = await client.open_table("table_one");
    /// ```
    #[wasm_bindgen]
    pub async fn open_table(&self, entity_id: String) -> ApiResult<Table> {
        Ok(Table(self.client.open_table(entity_id).await?))
    }

    /// 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`]).
    ///
    /// # JavaScript Examples
    ///
    /// ```javascript
    /// const tables = await client.get_hosted_table_names();
    /// ```
    #[wasm_bindgen]
    pub async fn get_hosted_table_names(&self) -> ApiResult<JsValue> {
        Ok(JsValue::from_serde_ext(
            &self.client.get_hosted_table_names().await?,
        )?)
    }

    /// Register a callback which is invoked whenever [`Client::table`] (on this
    /// [`Client`]) or [`Table::delete`] (on a [`Table`] belinging to this
    /// [`Client`]) are called.
    #[wasm_bindgen]
    pub async fn on_hosted_tables_update(&self, on_update_js: Function) -> ApiResult<u32> {
        let poll_loop = LocalPollLoop::new(move |_| on_update_js.call0(&JsValue::UNDEFINED));
        let on_update = Box::new(move || poll_loop.poll(()));
        let id = self.client.on_hosted_tables_update(on_update).await?;
        Ok(id)
    }

    /// Remove a callback previously registered via
    /// `Client::on_hosted_tables_update`.
    #[wasm_bindgen]
    pub async fn remove_hosted_tables_update(&self, update_id: u32) -> ApiResult<()> {
        self.client.remove_hosted_tables_update(update_id).await?;
        Ok(())
    }

    /// Provides the [`SystemInfo`] struct, implementation-specific metadata
    /// about the [`perspective_server::Server`] runtime such as Memory and
    /// CPU usage.
    ///
    /// For WebAssembly servers, this method includes the WebAssembly heap size.
    ///
    /// # JavaScript Examples
    ///
    /// ```javascript
    /// const info = await client.system_info();
    /// ```
    #[wasm_bindgen]
    pub async fn system_info(&self) -> ApiResult<JsValue> {
        let info = self.client.system_info().await?;
        Ok(JsValue::from_serde_ext(&info)?)
    }
}