feat: opt in telemetry through fuelup

fuelup-init.sh

@@ -149,6 +149,9 @@ main() {
         add_path_message
     fi
 
+    # Prompt for telemetry
+    prompt_telemetry
+
     return "$_retval"
 }
 
@@ -182,6 +185,44 @@ fish_add_path ~/.fuelup/bin
 EOF
 }
 
+prompt_telemetry() {
+    # Skip if the file already exists (user might have already been prompted)
+    if [ -f "$FUELUP_DIR/.telemetry_opt_in" ]; then
+        return
+    fi
+
+    # Check if running in a non-interactive environment (CI/CD, Docker, etc.)
+    # If no terminal is available, default to telemetry disabled
+    if [ ! -t 0 ] && [ ! -t 1 ]; then
+        printf "0" >"$FUELUP_DIR/.telemetry_opt_in"
+        return
+    fi
+
+    cat 1>&2 <<EOF
+
+Telemetry helps improve the Fuel toolchain by collecting anonymous usage data.
+You can change this setting at any time by running:
+  fuelup telemetry enable   # to enable telemetry
+  fuelup telemetry disable  # to disable telemetry
+
+Would you like to enable telemetry? (Y/n)
+EOF
+
+    # Default to yes if user just presses enter
+    read -r answer </dev/tty
+    case $answer in
+        "n" | "N" | "no" | "No" | "NO")
+            printf "0" >"$FUELUP_DIR/.telemetry_opt_in"
+            printf "\nTelemetry disabled. You can enable it later with 'fuelup telemetry enable'.\n\n"
+            ;;
+        *)
+            printf "1" >"$FUELUP_DIR/.telemetry_opt_in"
+            printf "\nTelemetry enabled. Thank you for helping improve the Fuel toolchain!\n"
+            printf "You can disable it at any time with 'fuelup telemetry disable'.\n\n"
+            ;;
+    esac
+}
+
 get_architecture() {
     local _ostype _cputype
     _ostype="$(uname -s)"

src/commands/mod.rs

@@ -3,5 +3,6 @@ pub mod completions;
 pub mod component;
 pub mod default;
 pub mod fuelup;
+pub mod telemetry;
 pub mod toolchain;
 pub mod upgrade;

src/commands/telemetry.rs

@@ -0,0 +1,87 @@
+use crate::fmt::{bold, colored_bold};
+use crate::telemetry::{get_telemetry_status, set_telemetry_status, TelemetryStatus};
+use anyhow::Result;
+use clap::Parser;
+use tracing::info;
+
+#[derive(Debug, Parser)]
+pub enum TelemetryCommand {
+    /// Show the current telemetry status
+    Status,
+    /// Enable telemetry (opt-in)
+    Enable,
+    /// Disable telemetry (opt-out)
+    Disable,
+}
+
+pub fn exec(command: TelemetryCommand) -> Result<()> {
+    match command {
+        TelemetryCommand::Status => show_status(),
+        TelemetryCommand::Enable => enable(),
+        TelemetryCommand::Disable => disable(),
+    }
+}
+
+fn show_status() -> Result<()> {
+    match get_telemetry_status()? {
+        Some(TelemetryStatus::Enabled) => {
+            info!(
+                "Telemetry is {}",
+                colored_bold(ansiterm::Color::Green, "enabled")
+            );
+            info!("");
+            info!("Telemetry helps improve the Fuel toolchain by collecting usage data.");
+            info!("To disable, run: {}", bold("fuelup telemetry disable"));
+        }
+        Some(TelemetryStatus::Disabled) => {
+            info!(
+                "Telemetry is {}",
+                colored_bold(ansiterm::Color::Yellow, "disabled")
+            );
+            info!("");
+            info!("Telemetry is currently disabled. No usage data will be collected.");
+            info!("To enable, run: {}", bold("fuelup telemetry enable"));
+        }
+        None => {
+            info!(
+                "Telemetry status is {}",
+                colored_bold(ansiterm::Color::Yellow, "not set")
+            );
+            info!("");
+            info!("Telemetry preference has not been set. It will be disabled by default.");
+            info!("To enable, run: {}", bold("fuelup telemetry enable"));
+            info!("To disable, run: {}", bold("fuelup telemetry disable"));
+        }
+    }
+    Ok(())
+}
+
+fn enable() -> Result<()> {
+    set_telemetry_status(TelemetryStatus::Enabled)?;
+    info!(
+        "Telemetry has been {}",
+        colored_bold(ansiterm::Color::Green, "enabled")
+    );
+    info!("");
+    info!("Thank you for helping improve the Fuel toolchain!");
+    info!(
+        "To disable at any time, run: {}",
+        bold("fuelup telemetry disable")
+    );
+    Ok(())
+}
+
+fn disable() -> Result<()> {
+    set_telemetry_status(TelemetryStatus::Disabled)?;
+    info!(
+        "Telemetry has been {}",
+        colored_bold(ansiterm::Color::Yellow, "disabled")
+    );
+    info!("");
+    info!("Telemetry will no longer collect usage data.");
+    info!(
+        "To enable at any time, run: {}",
+        bold("fuelup telemetry enable")
+    );
+    Ok(())
+}

src/fuelup_cli.rs

@@ -4,6 +4,7 @@ use crate::commands::{
     component::{self, ComponentCommand},
     default::{self, DefaultCommand},
     fuelup::{self, FuelupCommand},
+    telemetry::{self, TelemetryCommand},
     toolchain::{self, ToolchainCommand},
     upgrade::{self, UpgradeCommand},
 };
@@ -32,6 +33,9 @@ enum Commands {
     /// Manage your fuelup installation.
     #[clap(name = "self", subcommand)]
     Fuelup(FuelupCommand),
+    /// Manage telemetry settings
+    #[clap(subcommand)]
+    Telemetry(TelemetryCommand),
     /// Install new toolchains or modify/query installed toolchains
     #[clap(subcommand)]
     Toolchain(ToolchainCommand),
@@ -55,6 +59,7 @@ pub fn fuelup_cli() -> Result<()> {
             FuelupCommand::Update(update) => fuelup::update_exec(update.force),
             FuelupCommand::Uninstall(remove) => fuelup::remove_exec(remove.force),
         },
+        Commands::Telemetry(command) => telemetry::exec(command),
         Commands::Show => fuelup_show::show(),
         Commands::Toolchain(command) => toolchain::exec(command),
         Commands::Update => fuelup_update::update(),

src/lib.rs

@@ -16,5 +16,6 @@ pub mod settings;
 pub mod shell;
 pub mod store;
 pub mod target_triple;
+pub mod telemetry;
 pub mod toolchain;
 pub mod toolchain_override;

src/main.rs

@@ -3,6 +3,7 @@ use fuelup::{
     fuelup_cli,
     logging::{init_tracing, log_command, log_environment},
     proxy_cli,
+    telemetry::prompt_telemetry_if_needed,
 };
 use std::{env, panic, path::PathBuf};
 use tracing::error;
@@ -18,6 +19,10 @@ fn run() -> Result<()> {
         .and_then(std::ffi::OsStr::to_str)
         .map(String::from);
 
+    // Prompt for telemetry opt-in if needed (for both fuelup and proxy commands)
+    // This is a one-time prompt that creates the opt-in file
+    let _ = prompt_telemetry_if_needed();
+
     match process_name.as_deref() {
         Some(component::FUELUP) => {
             if let Err(e) = fuelup_cli::fuelup_cli() {

src/proxy_cli.rs

@@ -1,6 +1,7 @@
 use crate::{
     download::DownloadCfg,
     target_triple::TargetTriple,
+    telemetry::is_telemetry_enabled,
     toolchain::{DistToolchainDescription, Toolchain},
     toolchain_override::{ComponentSpec, ToolchainOverride},
 };
@@ -92,6 +93,15 @@ fn direct_proxy(proc_name: &str, args: &[OsString], toolchain: &Toolchain) -> Re
     cmd.args(args);
     cmd.stdin(Stdio::inherit());
 
+    // Set FUELUP_NO_TELEMETRY based on user's opt-in preference
+    // FUELUP_NO_TELEMETRY disables telemetry, so we set it when user has opted out
+    // and explicitly remove it when user has opted in (to override any inherited value)
+    if is_telemetry_enabled() {
+        cmd.env_remove("FUELUP_NO_TELEMETRY");
+    } else {
+        cmd.env("FUELUP_NO_TELEMETRY", "1");
+    }
+
     return exec(&mut cmd, proc_name, &toolchain_name).map_err(anyhow::Error::from);
 
     fn exec(cmd: &mut Command, proc_name: &str, toolchain_name: &str) -> io::Result<ExitCode> {