iggy 0.10.0

Iggy is the persistent message streaming platform written in Rust, supporting QUIC, TCP and HTTP transport protocols, capable of processing millions of messages per second.
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
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
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
/* Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

use crate::leader_aware::{LeaderRedirectionState, check_and_redirect_to_leader};
use crate::prelude::Client;
use crate::prelude::TcpClientConfig;
use crate::tcp::tcp_connection_stream::TcpConnectionStream;
use crate::tcp::tcp_connection_stream_kind::ConnectionStreamKind;
use crate::tcp::tcp_tls_connection_stream::TcpTlsConnectionStream;
use async_broadcast::{Receiver, Sender, broadcast};
use async_trait::async_trait;
use bytes::{BufMut, Bytes, BytesMut};
use iggy_common::{
    AutoLogin, ClientState, ConnectionString, ConnectionStringUtils, Credentials, DiagnosticEvent,
    IggyDuration, IggyError, IggyErrorDiscriminants, IggyTimestamp, TcpConnectionStringOptions,
    TransportProtocol,
};
use iggy_common::{BinaryClient, BinaryTransport, PersonalAccessTokenClient, UserClient};
use rustls::pki_types::{CertificateDer, ServerName, pem::PemObject};
use secrecy::ExposeSecret;
use std::net::SocketAddr;
use std::str::FromStr;
use std::sync::Arc;
use tokio::net::TcpStream;
use tokio::sync::Mutex;
use tokio::time::sleep;
use tokio_rustls::{TlsConnector, TlsStream};
use tracing::{error, info, trace, warn};

const REQUEST_INITIAL_BYTES_LENGTH: usize = 4;
const RESPONSE_INITIAL_BYTES_LENGTH: usize = 8;
const NAME: &str = "Iggy";

/// TCP client for interacting with the Iggy API.
/// It requires a valid server address.
#[derive(Debug)]
pub struct TcpClient {
    pub(crate) stream: Arc<Mutex<Option<ConnectionStreamKind>>>,
    pub(crate) config: Arc<TcpClientConfig>,
    pub(crate) state: Mutex<ClientState>,
    client_address: Mutex<Option<SocketAddr>>,
    events: (Sender<DiagnosticEvent>, Receiver<DiagnosticEvent>),
    pub(crate) connected_at: Mutex<Option<IggyTimestamp>>,
    leader_redirection_state: Mutex<LeaderRedirectionState>,
    pub(crate) current_server_address: Mutex<String>,
}

impl Default for TcpClient {
    fn default() -> Self {
        TcpClient::create(Arc::new(TcpClientConfig::default())).unwrap()
    }
}

#[async_trait]
impl Client for TcpClient {
    async fn connect(&self) -> Result<(), IggyError> {
        TcpClient::connect(self).await
    }

    async fn disconnect(&self) -> Result<(), IggyError> {
        TcpClient::disconnect(self).await
    }

    async fn shutdown(&self) -> Result<(), IggyError> {
        TcpClient::shutdown(self).await
    }

    async fn subscribe_events(&self) -> Receiver<DiagnosticEvent> {
        self.events.1.clone()
    }
}

#[async_trait]
#[async_trait]
impl BinaryTransport for TcpClient {
    async fn get_state(&self) -> ClientState {
        *self.state.lock().await
    }

    async fn set_state(&self, state: ClientState) {
        *self.state.lock().await = state;
    }

    async fn publish_event(&self, event: DiagnosticEvent) {
        if let Err(error) = self.events.0.broadcast(event).await {
            error!("Failed to send a TCP diagnostic event: {error}");
        }
    }

    async fn send_raw_with_response(&self, code: u32, payload: Bytes) -> Result<Bytes, IggyError> {
        let result = self.send_raw(code, payload.clone()).await;
        if result.is_ok() {
            return result;
        }

        let error = result.unwrap_err();
        if !matches!(
            error,
            IggyError::Disconnected
                | IggyError::EmptyResponse
                | IggyError::Unauthenticated
                | IggyError::StaleClient
                | IggyError::NotConnected
                | IggyError::CannotEstablishConnection
                | IggyError::TcpError
        ) {
            return Err(error);
        }

        if !self.config.reconnection.enabled {
            return Err(IggyError::Disconnected);
        }

        self.disconnect().await?;

        {
            let client_address = self.get_client_address_value().await;
            let server_address = self.current_server_address.lock().await.clone();
            info!(
                "Reconnecting to the server: {} by client: {client_address}...",
                server_address
            );
        }

        self.connect().await?;
        self.send_raw(code, payload).await
    }

    fn get_heartbeat_interval(&self) -> IggyDuration {
        self.config.heartbeat_interval
    }
}

impl BinaryClient for TcpClient {}

impl TcpClient {
    /// Create a new TCP client for the provided server address.
    pub fn new(
        server_address: &str,
        auto_sign_in: AutoLogin,
        heartbeat_interval: IggyDuration,
    ) -> Result<Self, IggyError> {
        Self::create(Arc::new(TcpClientConfig {
            heartbeat_interval,
            server_address: server_address.to_string(),
            auto_login: auto_sign_in,
            ..Default::default()
        }))
    }

    /// Create a new TCP client for the provided server address using TLS.
    pub fn new_tls(
        server_address: &str,
        domain: &str,
        auto_sign_in: AutoLogin,
        heartbeat_interval: IggyDuration,
    ) -> Result<Self, IggyError> {
        Self::create(Arc::new(TcpClientConfig {
            heartbeat_interval,
            server_address: server_address.to_string(),
            tls_enabled: true,
            tls_domain: domain.to_string(),
            auto_login: auto_sign_in,
            ..Default::default()
        }))
    }

    /// Create a new TCP client from the provided connection string.
    pub fn from_connection_string(connection_string: &str) -> Result<Self, IggyError> {
        if ConnectionStringUtils::parse_protocol(connection_string)? != TransportProtocol::Tcp {
            return Err(IggyError::InvalidConnectionString);
        }

        Self::create(Arc::new(
            ConnectionString::<TcpConnectionStringOptions>::from_str(connection_string)?.into(),
        ))
    }

    /// Create a new TCP client based on the provided configuration.
    pub fn create(config: Arc<TcpClientConfig>) -> Result<Self, IggyError> {
        let server_address = config.server_address.clone();
        Ok(Self {
            config,
            client_address: Mutex::new(None),
            stream: Arc::new(Mutex::new(None)),
            state: Mutex::new(ClientState::Disconnected),
            events: broadcast(1000),
            connected_at: Mutex::new(None),
            leader_redirection_state: Mutex::new(LeaderRedirectionState::new()),
            current_server_address: Mutex::new(server_address),
        })
    }

    async fn handle_response(
        status: u32,
        length: u32,
        stream: &mut ConnectionStreamKind,
    ) -> Result<Bytes, IggyError> {
        if status != 0 {
            // TEMP: See https://github.com/apache/iggy/pull/604 for context.
            if status == IggyErrorDiscriminants::TopicNameAlreadyExists as u32
                || status == IggyErrorDiscriminants::StreamNameAlreadyExists as u32
                || status == IggyErrorDiscriminants::UserAlreadyExists as u32
                || status == IggyErrorDiscriminants::PersonalAccessTokenAlreadyExists as u32
                || status == IggyErrorDiscriminants::ConsumerGroupNameAlreadyExists as u32
            {
                tracing::debug!(
                    "Received a server resource already exists response: {} ({})",
                    status,
                    IggyError::from_code_as_string(status)
                )
            } else {
                error!(
                    "Received an invalid response with status: {} ({}).",
                    status,
                    IggyError::from_code_as_string(status),
                );
            }

            return Err(IggyError::from_code(status));
        }

        trace!("Status: OK. Response length: {}", length);
        if length <= 1 {
            return Ok(Bytes::new());
        }

        let mut response_buffer = BytesMut::with_capacity(length as usize);
        response_buffer.put_bytes(0, length as usize);
        stream.read(&mut response_buffer).await?;
        Ok(response_buffer.freeze())
    }

    async fn connect(&self) -> Result<(), IggyError> {
        loop {
            match self.get_state().await {
                ClientState::Shutdown => {
                    trace!("Cannot connect. Client is shutdown.");
                    return Err(IggyError::ClientShutdown);
                }
                ClientState::Connected
                | ClientState::Authenticating
                | ClientState::Authenticated => {
                    let client_address = self.get_client_address_value().await;
                    trace!("Client: {client_address} is already connected.");
                    return Ok(());
                }
                ClientState::Connecting => {
                    trace!("Client is already connecting.");
                    return Ok(());
                }
                _ => {}
            }

            self.set_state(ClientState::Connecting).await;
            if let Some(connected_at) = self.connected_at.lock().await.as_ref() {
                let now = IggyTimestamp::now();
                let elapsed = now.as_micros() - connected_at.as_micros();
                let interval = self.config.reconnection.reestablish_after.as_micros();
                trace!(
                    "Elapsed time since last connection: {}",
                    IggyDuration::from(elapsed)
                );
                if elapsed < interval {
                    let remaining = IggyDuration::from(interval - elapsed);
                    info!("Trying to connect to the server in: {remaining}",);
                    sleep(remaining.get_duration()).await;
                }
            }

            let tls_enabled = self.config.tls_enabled;
            let mut retry_count = 0;
            let connection_stream: ConnectionStreamKind;
            let remote_address;
            let client_address;
            loop {
                let server_address = self.current_server_address.lock().await.clone();
                info!(
                    "{NAME} client is connecting to server: {}...",
                    server_address
                );

                let connection = TcpStream::connect(&server_address).await;
                if let Err(err) = &connection {
                    error!(
                        "Failed to connect to server: {}. Error: {}",
                        server_address, err
                    );
                    if !self.config.reconnection.enabled {
                        warn!("Automatic reconnection is disabled.");
                        return Err(IggyError::CannotEstablishConnection);
                    }

                    let unlimited_retries = self.config.reconnection.max_retries.is_none();
                    let max_retries = self.config.reconnection.max_retries.unwrap_or_default();
                    let max_retries_str =
                        if let Some(max_retries) = self.config.reconnection.max_retries {
                            max_retries.to_string()
                        } else {
                            "unlimited".to_string()
                        };

                    let interval_str = self.config.reconnection.interval.as_human_time_string();
                    if unlimited_retries || retry_count < max_retries {
                        retry_count += 1;
                        info!(
                            "Retrying to connect to server ({retry_count}/{max_retries_str}): {} in: {interval_str}",
                            server_address,
                        );
                        sleep(self.config.reconnection.interval.get_duration()).await;
                        continue;
                    }

                    self.set_state(ClientState::Disconnected).await;
                    self.publish_event(DiagnosticEvent::Disconnected).await;
                    return Err(IggyError::CannotEstablishConnection);
                }

                let stream = connection.map_err(|error| {
                    error!("Failed to establish TCP connection to the server: {error}",);
                    IggyError::CannotEstablishConnection
                })?;
                client_address = stream.local_addr().map_err(|error| {
                    error!("Failed to get the local address of the client: {error}",);
                    IggyError::CannotEstablishConnection
                })?;
                remote_address = stream.peer_addr().map_err(|error| {
                    error!("Failed to get the remote address of the server: {error}",);
                    IggyError::CannotEstablishConnection
                })?;
                self.client_address.lock().await.replace(client_address);

                if let Err(e) = stream.set_nodelay(self.config.nodelay) {
                    error!("Failed to set the nodelay option on the client: {e}, continuing...",);
                }

                if !tls_enabled {
                    connection_stream =
                        ConnectionStreamKind::Tcp(TcpConnectionStream::new(client_address, stream));
                    break;
                }

                let _ = rustls::crypto::aws_lc_rs::default_provider().install_default();

                let config = if self.config.tls_validate_certificate {
                    let mut root_cert_store = rustls::RootCertStore::empty();
                    if let Some(certificate_path) = &self.config.tls_ca_file {
                        for cert in
                            CertificateDer::pem_file_iter(certificate_path).map_err(|error| {
                                error!("Failed to read the CA file: {certificate_path}. {error}",);
                                IggyError::InvalidTlsCertificatePath
                            })?
                        {
                            let certificate = cert.map_err(|error| {
                            error!(
                                "Failed to read a certificate from the CA file: {certificate_path}. {error}",
                            );
                            IggyError::InvalidTlsCertificate
                        })?;
                            root_cert_store.add(certificate).map_err(|error| {
                            error!(
                                "Failed to add a certificate to the root certificate store. {error}",
                            );
                            IggyError::InvalidTlsCertificate
                        })?;
                        }
                    } else {
                        root_cert_store.extend(webpki_roots::TLS_SERVER_ROOTS.iter().cloned());
                    }

                    rustls::ClientConfig::builder()
                        .with_root_certificates(root_cert_store)
                        .with_no_client_auth()
                } else {
                    use crate::tcp::tcp_tls_verifier::NoServerVerification;
                    rustls::ClientConfig::builder()
                        .dangerous()
                        .with_custom_certificate_verifier(Arc::new(NoServerVerification))
                        .with_no_client_auth()
                };
                let connector = TlsConnector::from(Arc::new(config));
                let tls_domain = if self.config.tls_domain.is_empty() {
                    // Extract hostname/IP from server_address when tls_domain is not specified
                    server_address
                        .split(':')
                        .next()
                        .unwrap_or(&server_address)
                        .to_string()
                } else {
                    self.config.tls_domain.to_owned()
                };
                let domain = ServerName::try_from(tls_domain).map_err(|error| {
                    error!("Failed to create a server name from the domain. {error}",);
                    IggyError::InvalidTlsDomain
                })?;
                let stream = connector.connect(domain, stream).await.map_err(|error| {
                    error!("Failed to establish a TLS connection to the server: {error}",);
                    IggyError::CannotEstablishConnection
                })?;
                connection_stream = ConnectionStreamKind::TcpTls(TcpTlsConnectionStream::new(
                    client_address,
                    TlsStream::Client(stream),
                ));
                break;
            }

            let now = IggyTimestamp::now();
            info!(
                "{NAME} client: {client_address} has connected to server: {remote_address} at: {now}",
            );
            self.stream.lock().await.replace(connection_stream);
            self.set_state(ClientState::Connected).await;
            self.connected_at.lock().await.replace(now);
            self.publish_event(DiagnosticEvent::Connected).await;
            // Handle auto-login
            let should_redirect = match &self.config.auto_login {
                AutoLogin::Disabled => {
                    info!("Automatic sign-in is disabled.");
                    false
                }
                AutoLogin::Enabled(credentials) => {
                    info!("{NAME} client: {client_address} is signing in...");
                    self.set_state(ClientState::Authenticating).await;
                    match credentials {
                        Credentials::UsernamePassword(username, password) => {
                            self.login_user(username, password.expose_secret()).await?;
                            info!(
                                "{NAME} client: {client_address} has signed in with the user credentials, username: {username}",
                            );
                        }
                        Credentials::PersonalAccessToken(token) => {
                            self.login_with_personal_access_token(token.expose_secret())
                                .await?;
                            info!(
                                "{NAME} client: {client_address} has signed in with a personal access token.",
                            );
                        }
                    }

                    self.handle_leader_redirection().await?
                }
            };

            if should_redirect {
                continue;
            }

            return Ok(());
        }
    }

    /// Checks cluster metadata and handles leader redirection if needed.
    /// Returns true if redirection occurred and reconnection is needed.
    pub(crate) async fn handle_leader_redirection(&self) -> Result<bool, IggyError> {
        let current_address = self.current_server_address.lock().await.clone();
        let leader_address = check_and_redirect_to_leader(
            self,
            &current_address,
            iggy_common::TransportProtocol::Tcp,
        )
        .await?;

        if let Some(new_leader_address) = leader_address {
            let mut redirection_state = self.leader_redirection_state.lock().await;
            if !redirection_state.can_redirect() {
                warn!("Maximum leader redirections reached, continuing with current connection");
                return Ok(false);
            }

            info!(
                "Current node is not leader, redirecting to leader at: {}",
                new_leader_address
            );
            redirection_state.increment_redirect(new_leader_address.clone());
            drop(redirection_state);

            // Clear connected_at to avoid reestablish_after delay during redirection
            self.connected_at.lock().await.take();
            self.disconnect().await?;

            *self.current_server_address.lock().await = new_leader_address;
            Ok(true)
        } else {
            self.leader_redirection_state.lock().await.reset();
            Ok(false)
        }
    }

    async fn disconnect(&self) -> Result<(), IggyError> {
        if self.get_state().await == ClientState::Disconnected {
            return Ok(());
        }

        let client_address = self.get_client_address_value().await;
        info!("{NAME} client: {client_address} is disconnecting from server...");
        self.set_state(ClientState::Disconnected).await;
        self.stream.lock().await.take();
        self.publish_event(DiagnosticEvent::Disconnected).await;
        let now = IggyTimestamp::now();
        info!("{NAME} client: {client_address} has disconnected from server at: {now}.");
        Ok(())
    }

    async fn shutdown(&self) -> Result<(), IggyError> {
        if self.get_state().await == ClientState::Shutdown {
            return Ok(());
        }

        let client_address = self.get_client_address_value().await;
        info!("Shutting down the {NAME} TCP client: {client_address}");
        let stream = self.stream.lock().await.take();
        if let Some(mut stream) = stream {
            stream.shutdown().await?;
        }
        self.set_state(ClientState::Shutdown).await;
        self.publish_event(DiagnosticEvent::Shutdown).await;
        info!("{NAME} TCP client: {client_address} has been shutdown.");
        Ok(())
    }

    async fn send_raw(&self, code: u32, payload: Bytes) -> Result<Bytes, IggyError> {
        match self.get_state().await {
            ClientState::Shutdown => {
                trace!("Cannot send data. Client is shutdown.");
                return Err(IggyError::ClientShutdown);
            }
            ClientState::Disconnected => {
                trace!("Cannot send data. Client is not connected.");
                return Err(IggyError::NotConnected);
            }
            ClientState::Connecting => {
                trace!("Cannot send data. Client is still connecting.");
                return Err(IggyError::NotConnected);
            }
            _ => {}
        }

        let stream = self.stream.clone();
        // SAFETY: we run code holding the `stream` lock in a task so we can't be cancelled while holding the lock.
        tokio::spawn(async move {
            let mut stream = stream.lock().await;
            if let Some(stream) = stream.as_mut() {
                let payload_length = payload.len() + REQUEST_INITIAL_BYTES_LENGTH;
                trace!("Sending a TCP request of size {payload_length} with code: {code}");
                stream.write(&(payload_length as u32).to_le_bytes()).await?;
                stream.write(&code.to_le_bytes()).await?;
                stream.write(&payload).await?;
                stream.flush().await?;
                trace!("Sent a TCP request with code: {code}, waiting for a response...");
                let mut response_buffer = [0u8; RESPONSE_INITIAL_BYTES_LENGTH];
                let read_bytes = stream.read(&mut response_buffer).await.map_err(|error| {
                    error!(
                        "Failed to read response for TCP request with code: {code}: {error}",
                        code = code,
                        error = error
                    );
                    IggyError::Disconnected
                })?;

                if read_bytes != RESPONSE_INITIAL_BYTES_LENGTH {
                    error!("Received an invalid or empty response.");
                    return Err(IggyError::EmptyResponse);
                }

                let status = u32::from_le_bytes(
                    response_buffer[..4]
                        .try_into()
                        .map_err(|_| IggyError::InvalidNumberEncoding)?,
                );
                let length = u32::from_le_bytes(
                    response_buffer[4..]
                        .try_into()
                        .map_err(|_| IggyError::InvalidNumberEncoding)?,
                );
                return TcpClient::handle_response(status, length, stream).await;
            }

            error!("Cannot send data. Client is not connected.");
            Err(IggyError::NotConnected)
        })
        .await
        .map_err(|e| {
            error!("Task execution failed during TCP request: {}", e);
            IggyError::TcpError
        })?
    }

    async fn get_client_address_value(&self) -> String {
        let client_address = self.client_address.lock().await;
        if let Some(client_address) = &*client_address {
            client_address.to_string()
        } else {
            "unknown".to_string()
        }
    }
}

/// Unit tests for TcpClient.
/// Currently only tests for "from_connection_string()" are implemented.
/// TODO: Add complete unit tests for TcpClient.
#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn should_fail_with_empty_connection_string() {
        let value = "";
        let tcp_client = TcpClient::from_connection_string(value);
        assert!(tcp_client.is_err());
    }

    #[test]
    fn should_fail_without_username() {
        let connection_string_prefix = "iggy+";
        let protocol = TransportProtocol::Tcp;
        let server_address = "127.0.0.1";
        let port = "1234";
        let username = "";
        let password = "secret";
        let value = format!(
            "{connection_string_prefix}{protocol}://{username}:{password}@{server_address}:{port}"
        );
        let tcp_client = TcpClient::from_connection_string(&value);
        assert!(tcp_client.is_err());
    }

    #[test]
    fn should_fail_without_password() {
        let connection_string_prefix = "iggy+";
        let protocol = TransportProtocol::Tcp;
        let server_address = "127.0.0.1";
        let port = "1234";
        let username = "user";
        let password = "";
        let value = format!(
            "{connection_string_prefix}{protocol}://{username}:{password}@{server_address}:{port}"
        );
        let tcp_client = TcpClient::from_connection_string(&value);
        assert!(tcp_client.is_err());
    }

    #[test]
    fn should_fail_without_server_address() {
        let connection_string_prefix = "iggy+";
        let protocol = TransportProtocol::Tcp;
        let server_address = "";
        let port = "1234";
        let username = "user";
        let password = "secret";
        let value = format!(
            "{connection_string_prefix}{protocol}://{username}:{password}@{server_address}:{port}"
        );
        let tcp_client = TcpClient::from_connection_string(&value);
        assert!(tcp_client.is_err());
    }

    #[test]
    fn should_fail_without_port() {
        let connection_string_prefix = "iggy+";
        let protocol = TransportProtocol::Tcp;
        let server_address = "127.0.0.1";
        let port = "";
        let username = "user";
        let password = "secret";
        let value = format!(
            "{connection_string_prefix}{protocol}://{username}:{password}@{server_address}:{port}"
        );
        let tcp_client = TcpClient::from_connection_string(&value);
        assert!(tcp_client.is_err());
    }

    #[test]
    fn should_fail_with_invalid_prefix() {
        let connection_string_prefix = "invalid+";
        let protocol = TransportProtocol::Tcp;
        let server_address = "127.0.0.1";
        let port = "1234";
        let username = "user";
        let password = "secret";
        let value = format!(
            "{connection_string_prefix}{protocol}://{username}:{password}@{server_address}:{port}"
        );
        let tcp_client = TcpClient::from_connection_string(&value);
        assert!(tcp_client.is_err());
    }

    #[test]
    fn should_fail_with_unmatch_protocol() {
        let connection_string_prefix = "iggy+";
        let protocol = TransportProtocol::Quic;
        let server_address = "127.0.0.1";
        let port = "1234";
        let username = "user";
        let password = "secret";
        let value = format!(
            "{connection_string_prefix}{protocol}://{username}:{password}@{server_address}:{port}"
        );
        let tcp_client = TcpClient::from_connection_string(&value);
        assert!(tcp_client.is_err());
    }

    #[test]
    fn should_succeed_with_default_prefix() {
        let default_connection_string_prefix = "iggy://";
        let server_address = "127.0.0.1";
        let port = "1234";
        let username = "user";
        let password = "secret";
        let value = format!(
            "{default_connection_string_prefix}{username}:{password}@{server_address}:{port}"
        );
        let tcp_client = TcpClient::from_connection_string(&value);
        assert!(tcp_client.is_ok());
    }

    #[test]
    fn should_fail_with_invalid_options() {
        let connection_string_prefix = "iggy+";
        let protocol = TransportProtocol::Tcp;
        let server_address = "127.0.0.1";
        let port = "";
        let username = "user";
        let password = "secret";
        let value = format!(
            "{connection_string_prefix}{protocol}://{username}:{password}@{server_address}:{port}?invalid_option=invalid"
        );
        let tcp_client = TcpClient::from_connection_string(&value);
        assert!(tcp_client.is_err());
    }

    #[test]
    fn should_succeed_without_options() {
        let connection_string_prefix = "iggy+";
        let protocol = TransportProtocol::Tcp;
        let server_address = "127.0.0.1";
        let port = "1234";
        let username = "user";
        let password = "secret";
        let value = format!(
            "{connection_string_prefix}{protocol}://{username}:{password}@{server_address}:{port}"
        );
        let tcp_client = TcpClient::from_connection_string(&value);
        assert!(tcp_client.is_ok());

        let tcp_client_config = tcp_client.unwrap().config;
        assert_eq!(
            tcp_client_config.server_address,
            format!("{server_address}:{port}")
        );
        match &tcp_client_config.auto_login {
            AutoLogin::Enabled(Credentials::UsernamePassword(u, p)) => {
                assert_eq!(u, &username.to_string());
                assert_eq!(p.expose_secret(), password);
            }
            other => panic!("expected UsernamePassword auto_login, got {other:?}"),
        }

        assert!(!tcp_client_config.tls_enabled);
        assert!(tcp_client_config.tls_domain.is_empty());
        assert!(tcp_client_config.tls_ca_file.is_none());
        assert_eq!(
            tcp_client_config.heartbeat_interval,
            IggyDuration::from_str("5s").unwrap()
        );

        assert!(tcp_client_config.reconnection.enabled);
        assert!(tcp_client_config.reconnection.max_retries.is_none());
        assert_eq!(
            tcp_client_config.reconnection.interval,
            IggyDuration::from_str("1s").unwrap()
        );
        assert_eq!(
            tcp_client_config.reconnection.reestablish_after,
            IggyDuration::from_str("5s").unwrap()
        );
    }

    #[test]
    fn should_succeed_with_options() {
        let connection_string_prefix = "iggy+";
        let protocol = TransportProtocol::Tcp;
        let server_address = "127.0.0.1";
        let port = "1234";
        let username = "user";
        let password = "secret";
        let heartbeat_interval = "10s";
        let reconnection_retries = "10";
        let value = format!(
            "{connection_string_prefix}{protocol}://{username}:{password}@{server_address}:{port}?heartbeat_interval={heartbeat_interval}&reconnection_retries={reconnection_retries}"
        );
        let tcp_client = TcpClient::from_connection_string(&value);
        assert!(tcp_client.is_ok());

        let tcp_client_config = tcp_client.unwrap().config;
        assert_eq!(
            tcp_client_config.server_address,
            format!("{server_address}:{port}")
        );
        match &tcp_client_config.auto_login {
            AutoLogin::Enabled(Credentials::UsernamePassword(u, p)) => {
                assert_eq!(u, &username.to_string());
                assert_eq!(p.expose_secret(), password);
            }
            other => panic!("expected UsernamePassword auto_login, got {other:?}"),
        }

        assert!(!tcp_client_config.tls_enabled);
        assert!(tcp_client_config.tls_domain.is_empty());
        assert!(tcp_client_config.tls_ca_file.is_none());
        assert_eq!(
            tcp_client_config.heartbeat_interval,
            IggyDuration::from_str(heartbeat_interval).unwrap()
        );

        assert!(tcp_client_config.reconnection.enabled);
        assert_eq!(
            tcp_client_config.reconnection.max_retries.unwrap(),
            reconnection_retries.parse::<u32>().unwrap()
        );
        assert_eq!(
            tcp_client_config.reconnection.interval,
            IggyDuration::from_str("1s").unwrap()
        );
        assert_eq!(
            tcp_client_config.reconnection.reestablish_after,
            IggyDuration::from_str("5s").unwrap()
        );
    }

    #[test]
    fn should_succeed_with_pat() {
        let connection_string_prefix = "iggy+";
        let protocol = TransportProtocol::Tcp;
        let server_address = "127.0.0.1";
        let port = "1234";
        let pat = "iggypat-1234567890abcdef";
        let value = format!("{connection_string_prefix}{protocol}://{pat}@{server_address}:{port}");
        let tcp_client = TcpClient::from_connection_string(&value);
        assert!(tcp_client.is_ok());

        let tcp_client_config = tcp_client.unwrap().config;
        assert_eq!(
            tcp_client_config.server_address,
            format!("{server_address}:{port}")
        );
        match &tcp_client_config.auto_login {
            AutoLogin::Enabled(Credentials::PersonalAccessToken(t)) => {
                assert_eq!(t.expose_secret(), pat);
            }
            other => panic!("expected PersonalAccessToken auto_login, got {other:?}"),
        }

        assert!(!tcp_client_config.tls_enabled);
        assert!(tcp_client_config.tls_domain.is_empty());
        assert!(tcp_client_config.tls_ca_file.is_none());
        assert_eq!(
            tcp_client_config.heartbeat_interval,
            IggyDuration::from_str("5s").unwrap()
        );

        assert!(tcp_client_config.reconnection.enabled);
        assert!(tcp_client_config.reconnection.max_retries.is_none());
        assert_eq!(
            tcp_client_config.reconnection.interval,
            IggyDuration::from_str("1s").unwrap()
        );
        assert_eq!(
            tcp_client_config.reconnection.reestablish_after,
            IggyDuration::from_str("5s").unwrap()
        );
    }
}