[docs] init telemetry doc

Closes: aptos-labs#370

crates/aptos-telemetry/src/lib.rs

@@ -18,7 +18,7 @@ use uuid::Uuid;
 
 pub const GA_MEASUREMENT_ID: &str = "GA_MEASUREMENT_ID";
 pub const GA_API_SECRET: &str = "GA_API_SECRET";
-pub const APTOS_TELEMETRY_OPTOUT: &str = "APTOS_TELEMETRY_OPTOUT";
+pub const APTOS_TELEMETRY_DISABLE: &str = "APTOS_TELEMETRY_DISABLE";
 
 #[derive(Debug, Serialize, Deserialize)]
 struct MetricsDump {
@@ -39,8 +39,8 @@ struct Ip {
     origin: String,
 }
 
-pub fn is_optout() -> bool {
-    env::var(APTOS_TELEMETRY_OPTOUT).is_ok()
+pub fn is_disable() -> bool {
+    env::var(APTOS_TELEMETRY_DISABLE).is_ok()
 }
 
 async fn get_ip_origin() -> String {
@@ -55,15 +55,15 @@ async fn get_ip_origin() -> String {
 }
 
 pub async fn send_data(event_name: String, user_id: String, event_params: HashMap<String, String>) {
-    if is_optout() {
-        debug!("Error sending data: optout of Aptos telemetry");
+    if is_disable() {
+        debug!("Error sending data: disabled Aptos telemetry");
         return;
     }
 
     // parse environment variables
-    let api_secret = env::var(GA_API_SECRET).unwrap_or(constants::APTOS_GA_API_SECRET.to_string());
+    let api_secret = env::var(GA_API_SECRET).unwrap_or_else(|_| constants::APTOS_GA_API_SECRET.to_string());
     let measurement_id =
-        env::var(GA_MEASUREMENT_ID).unwrap_or(constants::APTOS_GA_MEASUREMENT_ID.to_string());
+        env::var(GA_MEASUREMENT_ID).unwrap_or_else(|_| constants::APTOS_GA_MEASUREMENT_ID.to_string());
 
     // dump event params in a new hashmap with some default params to include
     let mut new_event_params: HashMap<String, String> = event_params.clone();

developer-docs-site/docs/reference/telemetry.md

@@ -0,0 +1,34 @@
+---
+title: "Telemetry"
+slug: "telemetry"
+---
+
+At Aptos Labs, we develop software and services for the greater Aptos community and ecosystem. On top of community feedback, we use telemetry to help improve the decentralization of the network by understanding how our software is being deployed and run.
+
+The Aptos node binary collects telemetry such as software version, operating system information, and IP address. See [Types of information collected](#types-of-information-collected).
+
+The Aptos node binary does **not** collect personal information such as usernames or email addresses.
+
+Users can disable telemetry at any point. If telemetry remains enabled, Aptos node binary will send telemetry data in the background.
+
+# Disabling telemetry
+
+On macOs and Linux, you can disable telemetry by setting the `APTOS_TELEMETRY_DISABLE` environment variable to any value.
+
+```
+export APTOS_TELEMETRY_DISABLE=true
+```
+
+The above example only disables telemetry for a single session or terminal. To disable it everywhere, you must do so at shell startup.
+
+```
+echo "export APTOS_TELEMETRY_DISABLE=true" >> ~/.profile
+source ~/.profile
+```
+
+# Types of information collected
+
+* **Usage information** - Commands and subcommands that are run
+* **System information** - Operating system (Windows, Linux, macOS) and kernel information, CPU and memory utilization
+* **Software information** - Version of the Aptos node binary
+* **Node information** - Public IP address, number of inbound and outbound Aptos node connections

documentation/telemetry.md

@@ -0,0 +1 @@
+../developer-docs-site/docs/reference/telemetry.md