sl4f_lib/bluetooth/
gatt_client_facade.rs

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
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
// Copyright 2018 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

use anyhow::{format_err, Context as _, Error};
use fidl::endpoints;
use fidl_fuchsia_bluetooth_gatt2::{
    Characteristic, CharacteristicNotifierMarker, CharacteristicNotifierRequest,
    CharacteristicNotifierRequestStream, ClientEventStream, ClientProxy, Handle, LongReadOptions,
    ReadOptions, RemoteServiceEventStream, RemoteServiceProxy, ServiceHandle, ServiceInfo,
    ShortReadOptions, WriteMode, WriteOptions,
};
use fidl_fuchsia_bluetooth_le::{
    CentralMarker, CentralProxy, ConnectionEventStream, ConnectionOptions, ConnectionProxy, Filter,
    ScanOptions, ScanResultWatcherMarker, ScanResultWatcherProxy,
};
use fuchsia_sync::RwLock;
use futures::{select, StreamExt};
use std::collections::HashMap;
use std::str::FromStr;
use std::sync::Arc;
use tracing::*;
use {fuchsia_async as fasync, fuchsia_component as app};

use fuchsia_bluetooth::types::le::Peer;
use fuchsia_bluetooth::types::{PeerId, Uuid};

use crate::bluetooth::types::{BleScanResponse, SerializableReadByTypeResult};
use crate::common_utils::common::macros::with_line;

#[derive(Debug)]
struct Client {
    proxy: ClientProxy,
    _connection: ConnectionProxy,
    // Cache of services populated by GattClientFacade.list_services() and
    // watch_services_task.
    services: HashMap<u64, ServiceInfo>,
    // Task that processes Client.WatchServices() results. Started during the
    // initial call to GattClientFacade.list_services().
    watch_services_task: Option<fasync::Task<()>>,
    // Task listening for closed events from `proxy` and `_connection`.
    _events_task: fasync::Task<()>,
}

#[derive(Debug)]
struct Central {
    proxy: CentralProxy,
    _event_task: fasync::Task<Result<(), Error>>,
}

#[derive(Debug)]
struct RemoteService {
    proxy: RemoteServiceProxy,
    _event_task: fasync::Task<()>,
    // Map of characteristic IDs to CharacteristicNotifier tasks.
    notifier_tasks: HashMap<u64, fasync::Task<()>>,
    peer_id: PeerId,
    service_id: u64,
}

#[derive(Debug)]
pub struct InnerGattClientFacade {
    active_remote_service: Option<RemoteService>,
    central: Option<Central>,
    scan_results: HashMap<PeerId, Peer>,
    clients: HashMap<PeerId, Client>,
    scan_task: Option<fasync::Task<()>>,
}

/// Perform Gatt Client operations.
///
/// Note this object is shared among all threads created by server.
///
#[derive(Debug)]
pub struct GattClientFacade {
    inner: Arc<RwLock<InnerGattClientFacade>>,
}

impl GattClientFacade {
    pub fn new() -> GattClientFacade {
        GattClientFacade {
            inner: Arc::new(RwLock::new(InnerGattClientFacade {
                active_remote_service: None,
                central: None,
                scan_results: HashMap::new(),
                clients: HashMap::new(),
                scan_task: None,
            })),
        }
    }

    pub async fn stop_scan(&self) -> Result<(), Error> {
        let tag = "GattClientFacade::stop_scan";
        if self.inner.write().scan_task.take().is_some() {
            info!(tag = &with_line!(tag), "Scan stopped");
        } else {
            info!(tag = &with_line!(tag), "No scan was running");
        }
        Ok(())
    }

    pub async fn start_scan(&self, filter: Option<Filter>) -> Result<(), Error> {
        let tag = "GattClientFacade::start_scan";

        self.inner.write().scan_results.clear();

        // Set the central proxy if necessary and start a central_listener
        GattClientFacade::set_central_proxy(self.inner.clone());

        let central = self
            .inner
            .read()
            .central
            .as_ref()
            .ok_or_else(|| format_err!("No central proxy created."))?
            .proxy
            .clone();

        let options = ScanOptions {
            filters: Some(vec![filter.unwrap_or(Filter::default())]),
            ..Default::default()
        };

        let (watcher_proxy, watcher_server) =
            fidl::endpoints::create_proxy::<ScanResultWatcherMarker>();

        // Scan doesn't return until scanning has stopped. We don't care when scanning stops, so we
        // can detach a task to run the scan future.
        let scan_fut = central.scan(&options, watcher_server);
        fasync::Task::spawn(async move {
            if let Err(e) = scan_fut.await {
                warn!(tag = &with_line!(tag), "FIDL error during scan: {:?}", e);
            }
        })
        .detach();

        self.inner.write().scan_task = Some(fasync::Task::spawn(
            GattClientFacade::scan_result_watcher_task(self.inner.clone(), watcher_proxy),
        ));

        info!(tag = &with_line!(tag), "Scan started");
        Ok(())
    }

    async fn scan_result_watcher_task(
        inner: Arc<RwLock<InnerGattClientFacade>>,
        watcher_proxy: ScanResultWatcherProxy,
    ) {
        let tag = "GattClientFacade::scan_result_watcher_task";
        let mut event_stream = watcher_proxy.take_event_stream();
        let mut watch_fut = watcher_proxy.watch();
        loop {
            select! {
                  watch_result = watch_fut => {
                     let peers = match watch_result {
                          Ok(peers) => peers,
                          Err(e) => {
                               info!(
                                  tag = &with_line!(tag),
                                   "FIDL error calling ScanResultWatcher::Watch(): {}", e
                               );
                               break;
                           }};
                     for fidl_peer in peers {
                        let peer: Peer = fidl_peer.try_into().unwrap();
                        debug!(tag = &with_line!(tag), "Peer discovered (id: {}, name: {:?})", peer.id, peer.name);
                        inner.write().scan_results.insert(peer.id, peer);
                     }
                     watch_fut = watcher_proxy.watch();
                  },
                  event = event_stream.next() => {
                    if let Some(Err(err)) = event {
                              info!(tag = &with_line!(tag), "ScanResultWatcher error: {:?}", err);
                    }
                    break; // The only events are those that close the protocol.
                  }
            }
        }
        inner.write().scan_task = None;
        info!(tag = &with_line!(tag), "ScanResultWatcher closed");
    }

    async fn active_remote_service_event_task(
        inner: Arc<RwLock<InnerGattClientFacade>>,
        event_stream: RemoteServiceEventStream,
    ) {
        let tag = "GattClientFacade::active_remote_service_event_task";
        // There are no events
        event_stream.map(|_| ()).collect::<()>().await;
        info!(tag = &with_line!(tag), "RemoteService closed");
        inner.write().active_remote_service = None;
    }

    pub async fn gattc_connect_to_service(
        &self,
        peer_id: String,
        service_id: u64,
    ) -> Result<(), Error> {
        let tag = "GattClientFacade::gattc_connect_to_service";
        let peer_id = PeerId::from_str(&peer_id)?;

        // Check if the service is already the active service.
        if let Some(service) = self.inner.read().active_remote_service.as_ref() {
            if service.peer_id == peer_id && service.service_id == service_id {
                info!(
                    tag = &with_line!(tag),
                    "Aready connected to service (peer: {}, service: {})", peer_id, service_id
                );
                return Ok(());
            }
        }

        self.inner.write().active_remote_service = None;

        let client_proxy = self.get_client_proxy(peer_id).ok_or_else(|| {
            error!(
                tag = &with_line!(tag),
                "Unable to connect to service {} (not connected to peer {})", service_id, peer_id
            );
            format_err!("Not connected to peer")
        })?;
        let (proxy, server) = endpoints::create_proxy();
        client_proxy.connect_to_service(&ServiceHandle { value: service_id }, server)?;
        let event_stream = proxy.take_event_stream();
        let event_task = fasync::Task::spawn(GattClientFacade::active_remote_service_event_task(
            self.inner.clone(),
            event_stream,
        ));
        self.inner.write().active_remote_service = Some(RemoteService {
            proxy,
            _event_task: event_task,
            notifier_tasks: HashMap::new(),
            peer_id,
            service_id,
        });
        Ok(())
    }

    pub async fn gattc_discover_characteristics(&self) -> Result<Vec<Characteristic>, Error> {
        let discover_characteristics_fut = self
            .get_remote_service_proxy()
            .ok_or_else(|| format_err!("RemoteService proxy not available"))?
            .discover_characteristics();
        discover_characteristics_fut.await.map_err(|_| format_err!("Failed to send message"))
    }

    async fn gattc_write_char_internal(
        &self,
        id: u64,
        offset: u16,
        write_value: Vec<u8>,
        mode: WriteMode,
    ) -> Result<(), Error> {
        let handle = Handle { value: id };
        let options =
            WriteOptions { offset: Some(offset), write_mode: Some(mode), ..Default::default() };
        let write_fut = self
            .get_remote_service_proxy()
            .ok_or_else(|| format_err!("No active service"))?
            .write_characteristic(&handle, &write_value, &options);
        write_fut
            .await
            .map_err(|_| format_err!("Failed to send message"))?
            .map_err(|err| format_err!("Failed to write characteristic: {:?}", err))
    }

    pub async fn gattc_write_char_by_id(&self, id: u64, write_value: Vec<u8>) -> Result<(), Error> {
        self.gattc_write_char_internal(id, 0, write_value, WriteMode::Default).await
    }

    pub async fn gattc_write_long_char_by_id(
        &self,
        id: u64,
        offset: u16,
        write_value: Vec<u8>,
        reliable_mode: bool,
    ) -> Result<(), Error> {
        self.gattc_write_char_internal(
            id,
            offset,
            write_value,
            if reliable_mode { WriteMode::Reliable } else { WriteMode::Default },
        )
        .await
    }

    pub async fn gattc_write_char_by_id_without_response(
        &self,
        id: u64,
        write_value: Vec<u8>,
    ) -> Result<(), Error> {
        self.gattc_write_char_internal(id, 0, write_value, WriteMode::WithoutResponse).await
    }

    async fn gattc_read_char_internal(
        &self,
        id: u64,
        options: ReadOptions,
    ) -> Result<Vec<u8>, Error> {
        let handle = Handle { value: id };
        let read_fut = self
            .get_remote_service_proxy()
            .ok_or_else(|| format_err!("RemoteService proxy not available"))?
            .read_characteristic(&handle, &options);
        let read_value = read_fut
            .await
            .map_err(|_| format_err!("Failed to send message"))?
            .map_err(|err| format_err!("Failed to read long characteristic: {:?}", err))?;
        Ok(read_value.value.unwrap())
    }

    pub async fn gattc_read_char_by_id(&self, id: u64) -> Result<Vec<u8>, Error> {
        self.gattc_read_char_internal(id, ReadOptions::ShortRead(ShortReadOptions {})).await
    }

    pub async fn gattc_read_long_char_by_id(
        &self,
        id: u64,
        offset: u16,
        max_bytes: u16,
    ) -> Result<Vec<u8>, Error> {
        self.gattc_read_char_internal(
            id,
            ReadOptions::LongRead(LongReadOptions {
                offset: Some(offset),
                max_bytes: Some(max_bytes),
                ..Default::default()
            }),
        )
        .await
    }

    pub async fn gattc_read_char_by_type(
        &self,
        raw_uuid: String,
    ) -> Result<Vec<SerializableReadByTypeResult>, Error> {
        let uuid = Uuid::from_str(&raw_uuid)
            .map_err(|e| format_err!("Unable to convert to Uuid: {:?}", e))?;
        let fidl_uuid = fidl_fuchsia_bluetooth::Uuid::from(uuid);
        let read_fut = self
            .get_remote_service_proxy()
            .ok_or_else(|| format_err!("RemoteService proxy not available"))?
            .read_by_type(&fidl_uuid);
        let results = read_fut
            .await
            .map_err(|err| format_err!("FIDL error: {:?}", err))?
            .map_err(|err| format_err!("Failed to read characteristic by type: {:?}", err))?
            .into_iter()
            .filter(|r| r.error.is_none())
            .map(|r| SerializableReadByTypeResult::new(r).unwrap())
            .collect();
        Ok(results)
    }

    async fn gattc_read_desc_internal(
        &self,
        id: u64,
        options: ReadOptions,
    ) -> Result<Vec<u8>, Error> {
        let handle = Handle { value: id };
        let read_fut = self
            .get_remote_service_proxy()
            .ok_or_else(|| format_err!("RemoteService proxy not available"))?
            .read_descriptor(&handle, &options);
        let read_value = read_fut
            .await
            .map_err(|_| format_err!("Failed to send message"))?
            .map_err(|err| format_err!("Failed to read descriptor: {:?}", err))?;
        Ok(read_value.value.unwrap())
    }

    pub async fn gattc_read_desc_by_id(&self, id: u64) -> Result<Vec<u8>, Error> {
        self.gattc_read_desc_internal(id, ReadOptions::ShortRead(ShortReadOptions {})).await
    }

    pub async fn gattc_read_long_desc_by_id(
        &self,
        id: u64,
        offset: u16,
        max_bytes: u16,
    ) -> Result<Vec<u8>, Error> {
        self.gattc_read_desc_internal(
            id,
            ReadOptions::LongRead(LongReadOptions {
                offset: Some(offset),
                max_bytes: Some(max_bytes),
                ..Default::default()
            }),
        )
        .await
    }

    pub async fn gattc_write_desc_by_id(&self, id: u64, write_value: Vec<u8>) -> Result<(), Error> {
        self.gattc_write_long_desc_by_id(id, 0, write_value).await
    }

    pub async fn gattc_write_long_desc_by_id(
        &self,
        id: u64,
        offset: u16,
        write_value: Vec<u8>,
    ) -> Result<(), Error> {
        let handle = Handle { value: id };
        let options = WriteOptions { offset: Some(offset), ..Default::default() };
        let write_fut = self
            .get_remote_service_proxy()
            .ok_or_else(|| format_err!("RemoteService proxy not available"))?
            .write_descriptor(&handle, &write_value, &options);
        write_fut
            .await
            .map_err(|_| format_err!("Failed to send message"))?
            .map_err(|err| format_err!("Failed to write descriptor: {:?}", err))
    }

    async fn notifier_task(
        inner: Arc<RwLock<InnerGattClientFacade>>,
        id: u64,
        mut request_stream: CharacteristicNotifierRequestStream,
    ) {
        let tag = "GattClientFacade::notifier_task";
        while let Ok(event) = request_stream.select_next_some().await {
            match event {
                CharacteristicNotifierRequest::OnNotification { value, responder } => {
                    info!(
                        tag = &with_line!(tag),
                        "Received notification (id: {}, value: {:?})",
                        id,
                        value.value.unwrap()
                    );
                    let _ = responder.send();
                }
            }
        }
        info!(tag = &with_line!(tag), "CharacteristicNotifier closed (id: {})", id);
        inner.write().active_remote_service.as_mut().and_then(|s| s.notifier_tasks.remove(&id));
    }

    pub async fn gattc_toggle_notify_characteristic(
        &self,
        id: u64,
        enable: bool,
    ) -> Result<(), Error> {
        let (register_fut, request_stream) = {
            let mut inner = self.inner.write();
            let service = inner
                .active_remote_service
                .as_mut()
                .ok_or_else(|| format_err!("Not connected to a service"))?;

            if !enable {
                service.notifier_tasks.remove(&id);
                return Ok(());
            }
            if service.notifier_tasks.contains_key(&id) {
                return Ok(());
            }

            let (client_end, request_stream) =
                fidl::endpoints::create_request_stream::<CharacteristicNotifierMarker>();
            let register_fut =
                service.proxy.register_characteristic_notifier(&Handle { value: id }, client_end);

            (register_fut, request_stream)
        };
        register_fut
            .await
            .map_err(|e| format_err!("FIDL error: {:?}", e))?
            .map_err(|e| format_err!("Error registering notifier: {:?}", e))?;

        let notifier_task = fasync::Task::spawn(GattClientFacade::notifier_task(
            self.inner.clone(),
            id,
            request_stream,
        ));
        self.inner
            .write()
            .active_remote_service
            .as_mut()
            .ok_or_else(|| format_err!("Not connected to a service"))?
            .notifier_tasks
            .insert(id, notifier_task);
        Ok(())
    }

    // Warning: hangs forever if there are no service updates!
    async fn watch_services_and_update_map(
        inner: &Arc<RwLock<InnerGattClientFacade>>,
        peer_id: &PeerId,
    ) -> Result<(), Error> {
        let client_proxy = inner
            .read()
            .clients
            .get(peer_id)
            .ok_or_else(|| format_err!("Not connected to peer"))?
            .proxy
            .clone();
        let watch_fut = client_proxy.watch_services(&[]);
        let (updated, removed) =
            watch_fut.await.map_err(|_| format_err!("FIDL error calling WatchServices()"))?;

        // watch_services() returns a diff from the previous call, so we need to apply the diff to
        // the cached services to get an updated list of services.
        let mut inner = inner.write();
        let services = &mut inner
            .clients
            .get_mut(peer_id)
            .ok_or_else(|| format_err!("Not connected to peer"))?
            .services;
        for handle in removed {
            services.remove(&handle.value);
        }
        for svc in updated {
            services.insert(svc.handle.unwrap().value, svc);
        }
        Ok(())
    }

    async fn watch_services_task(inner: Arc<RwLock<InnerGattClientFacade>>, peer_id: PeerId) -> () {
        loop {
            let tag = "GattClientFacade::watch_services_task";
            if let Err(err) =
                GattClientFacade::watch_services_and_update_map(&inner, &peer_id).await
            {
                warn!(tag = &with_line!(tag), "{}", err);
                return;
            }
        }
    }

    pub async fn list_services(&self, id: String) -> Result<Vec<ServiceInfo>, Error> {
        let peer_id = PeerId::from_str(&id).map_err(|_| format_err!("Invalid peer id"))?;

        {
            let inner = self.inner.read();
            let client =
                inner.clients.get(&peer_id).ok_or_else(|| format_err!("Not connected to peer"))?;
            // If watch_services_task has already been started, then client.services has the latest cached list of services and we can simply return then.
            if client.watch_services_task.is_some() {
                return Ok(client.services.iter().map(|(_, svc)| svc.clone()).collect());
            }
        }

        // On the first call to list_services(), we need to get the initial list of services and start a task to get updates.
        GattClientFacade::watch_services_and_update_map(&self.inner, &peer_id).await?;
        let task =
            fasync::Task::spawn(GattClientFacade::watch_services_task(self.inner.clone(), peer_id));
        let mut inner = self.inner.write();
        let client =
            inner.clients.get_mut(&peer_id).ok_or_else(|| format_err!("Not connected to peer"))?;
        client.watch_services_task = Some(task);

        Ok(client.services.iter().map(|(_, svc)| svc.clone()).collect())
    }

    pub fn get_client_proxy(&self, id: PeerId) -> Option<ClientProxy> {
        self.inner.read().clients.get(&id).map(|c| c.proxy.clone())
    }

    async fn central_event_task(inner: Arc<RwLock<InnerGattClientFacade>>) -> Result<(), Error> {
        let tag = "GattClientFacade::central_event_task";

        let stream = inner
            .write()
            .central
            .as_ref()
            .ok_or_else(|| format_err!("Central not set"))?
            .proxy
            .take_event_stream();

        stream.map(|_| ()).collect::<()>().await;

        info!(tag = &with_line!(tag), "Central closed");
        inner.write().central.take();
        return Ok(());
    }

    // If no proxy exists, set up central server to listen for events.
    // Otherwise, do nothing.
    pub fn set_central_proxy(inner: Arc<RwLock<InnerGattClientFacade>>) {
        if inner.read().central.is_some() {
            return;
        }
        let proxy = app::client::connect_to_protocol::<CentralMarker>()
            .context("Failed to connect to BLE Central service.")
            .unwrap();
        let event_task = fasync::Task::spawn(GattClientFacade::central_event_task(inner.clone()));
        inner.write().central = Some(Central { proxy, _event_task: event_task });
    }

    async fn connection_event_task(
        inner: Arc<RwLock<InnerGattClientFacade>>,
        mut connection_stream: ConnectionEventStream,
        mut client_stream: ClientEventStream,
        peer_id: PeerId,
    ) {
        let tag = "GattClientFacade::connection_event_task";
        select! {
           _ = connection_stream.next() => info!(tag = &with_line!(tag) , "Connection to {} closed", peer_id),
           _ = client_stream.next() => info!(tag = &with_line!(tag), "Client for {} closed", peer_id),
        }
        inner.write().clients.remove(&peer_id);
    }

    pub async fn connect_peripheral(&self, id: String) -> Result<(), Error> {
        let tag = "GattClientFacade::connect_peripheral";
        let peer_id = PeerId::from_str(&id)?;

        if self.inner.read().clients.contains_key(&peer_id) {
            info!(tag = &with_line!(tag), "Already connected to {}", peer_id);
            return Ok(());
        }

        GattClientFacade::set_central_proxy(self.inner.clone());

        let (conn_proxy, conn_server_end) = fidl::endpoints::create_proxy();
        let options = ConnectionOptions { bondable_mode: Some(true), ..Default::default() };
        self.inner
            .read()
            .central
            .as_ref()
            .unwrap()
            .proxy
            .connect(&peer_id.clone().into(), &options, conn_server_end)
            .map_err(|_| format_err!("FIDL error when trying to connect()"))?;

        let (client_proxy, client_server_end) = fidl::endpoints::create_proxy();
        conn_proxy.request_gatt_client(client_server_end)?;

        let events_task = fasync::Task::spawn(GattClientFacade::connection_event_task(
            self.inner.clone(),
            conn_proxy.take_event_stream(),
            client_proxy.take_event_stream(),
            peer_id.clone(),
        ));

        self.inner.write().clients.insert(
            peer_id,
            Client {
                proxy: client_proxy,
                _connection: conn_proxy,
                services: HashMap::new(),
                watch_services_task: None,
                _events_task: events_task,
            },
        );

        Ok(())
    }

    pub async fn disconnect_peripheral(&self, id: String) -> Result<(), Error> {
        let peer_id = PeerId::from_str(&id)?;
        self.inner.write().clients.remove(&peer_id);
        Ok(())
    }

    // Return the central proxy
    pub fn get_central_proxy(&self) -> Option<CentralProxy> {
        self.inner.read().central.as_ref().map(|c| c.proxy.clone())
    }

    fn get_remote_service_proxy(&self) -> Option<RemoteServiceProxy> {
        self.inner.read().active_remote_service.as_ref().map(|s| s.proxy.clone())
    }

    // Returns scan responses converted to BleScanResponses
    pub fn get_scan_responses(&self) -> Vec<BleScanResponse> {
        const EMPTY_DEVICE: &str = "";
        let mut devices = Vec::new();
        for (peer_id, peer) in &self.inner.read().scan_results {
            let id = format!("{}", peer_id);
            let name = peer.name.clone().unwrap_or_else(|| EMPTY_DEVICE.to_string());
            let connectable = peer.connectable;
            devices.push(BleScanResponse::new(id, name, connectable));
        }
        devices
    }

    pub fn print(&self) {
        let tag = "GattClientFacade::print";
        let inner = self.inner.read();
        info!(
            tag = &with_line!(tag),
            "Central: {:?}, Active Service: {:?}, Scan Results: {:?}, Clients: {:?}",
            inner.central,
            inner.active_remote_service,
            inner.scan_results,
            inner.clients,
        );
    }

    pub fn cleanup(&self) {
        let mut inner = self.inner.write();
        inner.active_remote_service = None;
        inner.central = None;
        inner.scan_results.clear();
        inner.clients.clear();
        inner.scan_task = None;
    }
}