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
|
use batcher::{BatchConfigBuilder, BatchDriver, BatchDriverInput, BatchDriverOutput, Batcher};
use mqtt_channel::{Connection, Message, QoS, SinkExt, StreamExt, Topic, TopicFilter};
use tracing::{error, info, instrument};
use super::{batcher::MessageBatch, collectd::CollectdMessage, error::DeviceMonitorError};
const DEFAULT_HOST: &str = "localhost";
const DEFAULT_PORT: u16 = 1883;
const DEFAULT_MQTT_CLIENT_ID: &str = "collectd-mapper";
const DEFAULT_BATCHING_WINDOW: u32 = 500;
const DEFAULT_MAXIMUM_MESSAGE_DELAY: u32 = 400; // Heuristic delay that should work out well on an Rpi
const DEFAULT_MESSAGE_LEAP_LIMIT: u32 = 0;
const DEFAULT_MQTT_SOURCE_TOPIC: &str = "collectd/#";
const DEFAULT_MQTT_TARGET_TOPIC: &str = "tedge/measurements";
#[derive(Debug)]
pub struct DeviceMonitorConfig {
host: String,
port: u16,
mqtt_client_id: &'static str,
pub mqtt_source_topic: &'static str,
mqtt_target_topic: &'static str,
batching_window: u32,
maximum_message_delay: u32,
message_leap_limit: u32,
}
impl Default for DeviceMonitorConfig {
fn default() -> Self {
Self {
host: DEFAULT_HOST.to_string(),
port: DEFAULT_PORT,
mqtt_client_id: DEFAULT_MQTT_CLIENT_ID,
mqtt_source_topic: DEFAULT_MQTT_SOURCE_TOPIC,
mqtt_target_topic: DEFAULT_MQTT_TARGET_TOPIC,
batching_window: DEFAULT_BATCHING_WINDOW,
maximum_message_delay: DEFAULT_MAXIMUM_MESSAGE_DELAY,
message_leap_limit: DEFAULT_MESSAGE_LEAP_LIMIT,
}
}
}
impl DeviceMonitorConfig {
pub fn with_port(self, port: u16) -> Self {
Self { port, ..self }
}
pub fn with_host(self, host: String) -> Self {
Self { host, ..self }
}
}
#[derive(Debug)]
pub struct DeviceMonitor {
device_monitor_config: DeviceMonitorConfig,
}
impl DeviceMonitor {
pub fn new(device_monitor_config: DeviceMonitorConfig) -> Self {
Self {
device_monitor_config,
}
}
#[instrument(skip(self), name = "monitor")]
pub async fn run(&self) -> Result<(), DeviceMonitorError> {
let input_topic = TopicFilter::new(self.device_monitor_config.mqtt_source_topic)?
.with_qos(QoS::AtMostOnce);
let mqtt_config = mqtt_channel::Config::new(
self.device_monitor_config.host.to_string(),
self.device_monitor_config.port,
)
.with_session_name(self.device_monitor_config.mqtt_client_id)
.with_subscriptions(input_topic);
let mqtt_client = Connection::new(&mqtt_config).await?;
let batch_config = BatchConfigBuilder::new()
.event_jitter(self.device_monitor_config.batching_window)
.delivery_jitter(self.device_monitor_config.maximum_message_delay)
.message_leap_limit(self.device_monitor_config.message_leap_limit)
.build();
let (msg_send, msg_recv) = tokio::sync::mpsc::channel(100);
let (batch_send, mut batch_recv) = tokio::sync::mpsc::channel(100);
let driver = BatchDriver::new(Batcher::new(batch_config), msg_recv, batch_send);
let driver_join_handle = tokio::task::spawn(async move {
match driver.run().await {
Ok(_) => error!("Unexpected end of message batcher thread"),
Err(err) => error!("Error in message batcher thread: {}", err),
}
});
let mut collectd_messages = mqtt_client.received;
let input_join_handle = tokio::task::spawn(async move {
while let Some(message) = collectd_messages.next().await {
match CollectdMessage::parse_from(&message) {
Ok(collectd_message) => {
for msg in collectd_message {
let batch_input = BatchDriverInput::Event(msg);
if let Err(err) = msg_send.send(batch_input).await {
error!("Error while processing a collectd message: {}", err);
}
}
}
Err(err) => {
error!("Error while decoding a collectd message: {}", err);
}
}
}
// The MQTT connection has been closed by the process itself.
info!("Stop batching");
let eof = BatchDriverInput::Flush;
msg_send.send(eof).await
});
let output_topic = Topic::new(self.device_monitor_config.mqtt_target_topic)?;
let mut output_messages = mqtt_client.published;
let output_join_handle = tokio::task::spawn(async move {
loop {
match batch_recv.recv().await {
None | Some(BatchDriverOutput::Flush) => {
break;
}
Some(BatchDriverOutput::Batch(messages)) => {
match MessageBatch::thin_edge_json_bytes(messages) {
Ok(payload) => {
let tedge_message = Message::new(&output_topic, payload);
if let Err(err) = output_messages.send(tedge_message).await {
error!("Error while sending a thin-edge json message: {}", err);
}
}
Err(err) => {
error!("Error while encoding a thin-edge json message: {}", err);
}
}
}
}
}
// All the messages forwarded for batching have been processed.
info!("Batching done");
});
let mut mqtt_errors = mqtt_client.errors;
let error_join_handle = tokio::task::spawn(async move {
while let Some(error) = mqtt_errors.next().await {
error!("MQTT error: {}", error);
}
});
let _ = driver_join_handle.await;
let _ = input_join_handle.await;
let _ = output_join_handle.await;
let _ = error_join_handle.await;
Ok(())
}
}
|
