6 files changed, 203 insertions, 0 deletions
diff --git a/common/rust/BUILD.bazel b/common/rust/BUILD.bazel
new file mode 100644
index 0000000..0fbd9b2
--- /dev/null
+++ b/common/rust/BUILD.bazel
@@ -0,0 +1,9 @@
+load("@rules_rust//rust:defs.bzl", "rust_library")
+load("//cargo:crates.bzl", "all_crate_deps")
+
+rust_library(
+    name = "common",
+    srcs = glob(["src/**"]),
+    visibility = ["//visibility:public"],
+    deps = all_crate_deps(),
+)
diff --git a/common/rust/Cargo.toml b/common/rust/Cargo.toml
new file mode 100644
index 0000000..d631c6c
--- /dev/null
+++ b/common/rust/Cargo.toml
@@ -0,0 +1,13 @@
+[package]
+name = "common"
+version = "0.1.0"
+edition = "2018"
+
+[dependencies]
+pretty_env_logger = "0.4"
+log = { version = "0.4", features = ["std"] }
+serde = { version = "1.0.8", features = ["derive"] }
+config = "0.11"
+hyper = { version = "0.14", features = ["full"] }
+tokio = { version = "1", features = ["full"] }
+prometheus = "0.12.0"
+\ No newline at end of file
diff --git a/common/rust/cargo/BUILD.bazel b/common/rust/cargo/BUILD.bazel
new file mode 100644
index 0000000..ff92458
--- /dev/null
+++ b/common/rust/cargo/BUILD.bazel
@@ -0,0 +1,76 @@
+"""
+@generated
+cargo-raze generated Bazel file.
+
+DO NOT EDIT! Replaced on runs of cargo-raze
+"""
+
+package(default_visibility = ["//visibility:public"])
+
+licenses([
+    "notice",  # See individual crates for specific licenses
+])
+
+# Aliased targets
+alias(
+    name = "config",
+    actual = "@raze__config__0_11_0//:config",
+    tags = [
+        "cargo-raze",
+        "manual",
+    ],
+)
+
+alias(
+    name = "hyper",
+    actual = "@raze__hyper__0_14_12//:hyper",
+    tags = [
+        "cargo-raze",
+        "manual",
+    ],
+)
+
+alias(
+    name = "log",
+    actual = "@raze__log__0_4_14//:log",
+    tags = [
+        "cargo-raze",
+        "manual",
+    ],
+)
+
+alias(
+    name = "pretty_env_logger",
+    actual = "@raze__pretty_env_logger__0_4_0//:pretty_env_logger",
+    tags = [
+        "cargo-raze",
+        "manual",
+    ],
+)
+
+alias(
+    name = "prometheus",
+    actual = "@raze__prometheus__0_12_0//:prometheus",
+    tags = [
+        "cargo-raze",
+        "manual",
+    ],
+)
+
+alias(
+    name = "serde",
+    actual = "@raze__serde__1_0_130//:serde",
+    tags = [
+        "cargo-raze",
+        "manual",
+    ],
+)
+
+alias(
+    name = "tokio",
+    actual = "@raze__tokio__1_11_0//:tokio",
+    tags = [
+        "cargo-raze",
+        "manual",
+    ],
+)
diff --git a/common/rust/src/config.rs b/common/rust/src/config.rs
new file mode 100644
index 0000000..6d8fb33
--- /dev/null
+++ b/common/rust/src/config.rs
@@ -0,0 +1,41 @@
+use std::env;
+
+use config::{Config, ConfigError, Environment, File};
+use log::info;
+use serde::{Deserialize};
+
+
+#[derive(Debug, Deserialize, Clone)]
+#[serde(bound(deserialize = "T: Deserialize<'de> + std::default::Default + Clone"))]
+pub struct Settings<T> {
+    #[serde(skip_deserializing)]
+    pub config: T,
+    pub monitoring: crate::monitoring::MonitoringConfiguration,
+}
+
+impl<T> Settings<T> where T: Deserialize<'static> + std::default::Default + Clone {
+    pub fn new(service_name: &str) -> Result<Settings<T>, ConfigError> {
+        let mut default = Config::default();
+        // this file my be shared with all the components
+        default.merge(File::with_name("config/default"))?;
+        let mode = env::var("ENV").unwrap_or_else(|_| "development".into());
+        info!("Configuration Environment: {}", mode);
+
+        default.merge(File::with_name(&format!("config/{}", mode)).required(false))?;
+        default.merge(File::with_name("config/local").required(false))?;
+
+        // we can configure each component using environment variables
+        default.merge(Environment::with_prefix(&format!("NOVA_{}", service_name)))?;
+        let mut config: Settings<T> = default.clone().try_into().unwrap();
+
+        //  try to load the config
+        config.config = default.get::<T>(&service_name).unwrap();
+
+        // setup the logger
+        pretty_env_logger::init_custom_env(&format!("NOVA_{}_LOG", service_name));
+
+        // start the monitoring system if needed
+        crate::monitoring::start_monitoring(&config.monitoring);
+        Ok(config)
+    }
+}
diff --git a/common/rust/src/lib.rs b/common/rust/src/lib.rs
new file mode 100644
index 0000000..5122334
--- /dev/null
+++ b/common/rust/src/lib.rs
@@ -0,0 +1,4 @@
+/// This crate contains shared code in all the rust projects
+/// It contains utilities such as monitoring, logging and more.
+pub mod config;
+pub mod monitoring;
+\ No newline at end of file
diff --git a/common/rust/src/monitoring.rs b/common/rust/src/monitoring.rs
new file mode 100644
index 0000000..ded1d95
--- /dev/null
+++ b/common/rust/src/monitoring.rs
@@ -0,0 +1,60 @@
+use hyper::{
+    Response, Body, Request, Server,
+    header::{CONTENT_TYPE},
+    service::{make_service_fn, service_fn},
+};
+use std::net::ToSocketAddrs;
+use prometheus::{Encoder, TextEncoder};
+use log::{info,error};
+use serde::Deserialize;
+
+#[derive(Clone, Debug, Deserialize)]
+/// Options for the monitoring service
+pub struct MonitoringConfiguration {
+    enabled: bool,
+    address: Option<String>,
+    port: Option<i32>,
+}
+
+/// Handler for the hyper http server
+async fn serve_metrics(_request: Request<Body>) -> Result<Response<Body>, hyper::Error> {
+    let encoder = TextEncoder::new();
+    let metrics = prometheus::gather();
+
+    let mut buffer = vec![];
+    encoder.encode(&metrics, &mut buffer).unwrap();
+
+    let response = Response::builder()
+        .status(200)
+        .header(CONTENT_TYPE, encoder.format_type())
+        .body(Body::from(buffer))
+        .unwrap();
+    Ok(response)
+}
+
+/// Starts a monitoring server on the requested port
+pub fn start_monitoring(configuration: &MonitoringConfiguration) {
+    let config = configuration.clone();
+    tokio::task::spawn(async move {
+        if config.enabled {
+            let address = format!("{}:{}",
+                config.address.expect("a listening address must be specified for the metrics server"),
+                config.port.expect("a listening port must be specified for the metrics server")
+            );
+            info!("Starting monitoring server on {}", address);
+            
+            let listen_address = address
+                .to_socket_addrs()
+                .unwrap()
+                .next()
+                .unwrap();
+            let server = Server::bind(&listen_address).serve(make_service_fn(|_| async {
+                Ok::<_, hyper::Error>(service_fn(serve_metrics))
+            }));
+
+            if let Err(e) = server.await {
+                error!("failed to start the monitoring server {}", e);
+            }
+        }
+    });
+}
+\ No newline at end of file