Reconnect telemetry

Signed-off-by: Alexey Kalita <kalita.alexey@outlook.com>

core/genesis.json

@@ -11,7 +11,7 @@
                     "name": "wonderland",
                     "accounts": {},
                     "asset_definitions": {},
-					"metadata": {} 
+                    "metadata": {}
                   }
                 }
               }

docs/source/references/config.md

@@ -83,6 +83,8 @@ Configuration of iroha is done via options in the following document. Here is de
   "TELEMETRY": {
     "NAME": null,
     "URL": null,
+    "MIN_PERIOD": 1,
+    "MAX_EXPONENT": 4,
     "FILE": null
   },
   "NETWORK": {
@@ -530,6 +532,8 @@ Has type `iroha_telemetry::Configuration`. Can be configured via environment var
 ```json
 {
   "FILE": null,
+  "MAX_EXPONENT": 4,
+  "MIN_PERIOD": 1,
   "NAME": null,
   "URL": null
 }
@@ -545,6 +549,26 @@ Has type `Option<PathBuf>`. Can be configured via environment variable `TELEMETR
 null
 ```
 
+### `telemetry.max_exponent`
+
+The maximum exponent of 2 that is used for increasing delay between reconnections
+
+Has type `u8`. Can be configured via environment variable `TELEMETRY_MAX_EXPONENT`
+
+```json
+4
+```
+
+### `telemetry.min_period`
+
+The minimum period of time in seconds to wait before reconnecting
+
+Has type `u64`. Can be configured via environment variable `TELEMETRY_MIN_PERIOD`
+
+```json
+1
+```
+
 ### `telemetry.name`
 
 The node's name to be seen on the telemetry

telemetry/Cargo.toml

@@ -9,6 +9,7 @@ build = "build.rs"
 dev-telemetry = []
 
 [dependencies]
+async-trait = "0.1"
 chrono = "0.4"
 eyre = "0.6.5"
 futures = { version = "0.3.17", default-features = false, features = ["std", "async-await"] }

telemetry/src/config.rs

@@ -5,9 +5,12 @@ use iroha_config::derive::Configurable;
 use serde::{Deserialize, Serialize};
 use url::Url;
 
+use crate::types::RetryPeriod;
+
 /// Configuration parameters container
-#[derive(Clone, Default, Deserialize, Serialize, Debug, Configurable, PartialEq, Eq)]
+#[derive(Clone, Deserialize, Serialize, Debug, Configurable, PartialEq, Eq)]
 #[serde(rename_all = "UPPERCASE")]
+#[serde(default)]
 #[config(env_prefix = "TELEMETRY_")]
 pub struct Configuration {
     /// The node's name to be seen on the telemetry
@@ -16,8 +19,35 @@ pub struct Configuration {
     /// The url of the telemetry, e.g., ws://127.0.0.1:8001/submit
     #[config(serde_as_str)]
     pub url: Option<Url>,
+    /// The minimum period of time in seconds to wait before reconnecting
+    #[serde(default = "default_min_period")]
+    pub min_period: u64,
+    /// The maximum exponent of 2 that is used for increasing delay between reconnections
+    #[serde(default = "default_max_exponent")]
+    pub max_exponent: u8,
     /// The filepath that to write dev-telemetry to
     #[cfg(feature = "dev-telemetry")]
     #[config(serde_as_str)]
     pub file: Option<PathBuf>,
 }
+
+impl Default for Configuration {
+    fn default() -> Self {
+        Self {
+            name: None,
+            url: None,
+            min_period: RetryPeriod::DEFAULT_MIN_PERIOD,
+            max_exponent: RetryPeriod::DEFAULT_MAX_EXPONENT,
+            #[cfg(feature = "dev-telemetry")]
+            file: None,
+        }
+    }
+}
+
+fn default_min_period() -> u64 {
+    RetryPeriod::DEFAULT_MIN_PERIOD
+}
+
+fn default_max_exponent() -> u8 {
+    RetryPeriod::DEFAULT_MAX_EXPONENT
+}

telemetry/src/lib.rs

@@ -4,6 +4,7 @@ mod config;
 #[cfg(feature = "dev-telemetry")]
 pub mod dev;
 pub mod futures;
+mod types;
 pub mod ws;
 
 pub use config::Configuration;

telemetry/src/types.rs

@@ -0,0 +1,41 @@
+/// Encapsulates the retry period that is calculated as `min_period + 2 ^ min(exponent, max_exponent)`
+pub struct RetryPeriod {
+    /// The minimum period
+    min_period: u64,
+    /// The maximum exponent
+    max_exponent: u8,
+    /// The current exponent
+    exponent: u8,
+}
+
+impl RetryPeriod {
+    pub const DEFAULT_MIN_PERIOD: u64 = 1;
+    pub const DEFAULT_MAX_EXPONENT: u8 = 4;
+
+    /// Constructs a new object
+    pub fn new(min_period: u64, max_exponent: u8) -> Self {
+        Self {
+            min_period,
+            max_exponent,
+            exponent: 0,
+        }
+    }
+
+    /// Increases the exponent if it isn't at its maximum
+    pub fn increase_exponent(&mut self) {
+        if self.exponent < self.max_exponent {
+            self.exponent += 1;
+        }
+    }
+
+    /// Returns the period
+    pub fn period(&mut self) -> u64 {
+        self.min_period + 2_u64.saturating_mul(self.exponent.into())
+    }
+}
+
+impl Default for RetryPeriod {
+    fn default() -> Self {
+        Self::new(Self::DEFAULT_MIN_PERIOD, Self::DEFAULT_MAX_EXPONENT)
+    }
+}