Limit parallel network requests to a default of 10, and allow configuring it via a command line flag

Author: theRookieCoder

Cargo.lock

@@ -52,6 +52,7 @@ tokio = { version = "1.40", default-features = false, features = [
     "rt-multi-thread",
     "macros",
 ] }
+rustls = { version = "0.23", features = ["ring"] }
 clap = { version = "4.5", features = ["derive"] }
 clap_complete = "4.5"
 serde_json = "1.0"

Cargo.toml

@@ -15,6 +15,9 @@ pub struct Ferium {
     /// You can also use the environment variable `TOKIO_WORKER_THREADS`.
     #[clap(long, short)]
     pub threads: Option<usize>,
+    /// Specify the maximum number of parallel network requests to perform.
+    #[clap(long, short = 'p')]
+    pub parallel_network: Option<usize>,
     /// Set a GitHub personal access token for increasing the GitHub API rate limit.
     /// You can also use the environment variable `GITHUB_TOKEN`.
     #[clap(long, visible_alias = "gh")]

src/cli.rs

@@ -1,6 +1,6 @@
 #![expect(clippy::expect_used, reason = "For mutex poisons")]
 
-use crate::{STYLE_BYTE, TICK};
+use crate::{DEFAULT_PARALLEL_NETWORK, PARALLEL_NETWORK, STYLE_BYTE, TICK};
 use anyhow::{anyhow, bail, Error, Result};
 use colored::Colorize as _;
 use fs_extra::{
@@ -19,8 +19,6 @@ use std::{
 };
 use tokio::sync::Semaphore;
 
-const CONCURRENT_DOWNLOADS: usize = 6;
-
 /// Check the given `directory`
 ///
 /// - If there are files there that are not in `to_download` or `to_install`, they will be moved to `directory`/.old
@@ -115,7 +113,9 @@ pub async fn download(
         .expect("Mutex poisoned")
         .enable_steady_tick(Duration::from_millis(100));
     let mut tasks = FuturesUnordered::new();
-    let semaphore = Arc::new(Semaphore::new(CONCURRENT_DOWNLOADS));
+    let semaphore = Arc::new(Semaphore::new(
+        *PARALLEL_NETWORK.get_or_init(|| DEFAULT_PARALLEL_NETWORK),
+    ));
     let client = reqwest::Client::new();
 
     for downloadable in to_download {
@@ -126,6 +126,7 @@ pub async fn download(
 
         tasks.push(async move {
             let _permit = semaphore.acquire_owned().await?;
+
             let (length, filename) = downloadable
                 .download(&client, &output_dir, |additional| {
                     progress_bar

src/download.rs

@@ -38,12 +38,15 @@ use libium::{
 use std::{
     env::{set_var, var_os},
     process::ExitCode,
-    sync::LazyLock,
+    sync::{LazyLock, OnceLock},
 };
 
 const CROSS: &str = "×";
 static TICK: LazyLock<ColoredString> = LazyLock::new(|| "✓".green());
 
+pub static PARALLEL_NETWORK: OnceLock<usize> = OnceLock::new();
+pub const DEFAULT_PARALLEL_NETWORK: usize = 10;
+
 /// Indicatif themes
 #[expect(clippy::expect_used)]
 pub static STYLE_NO: LazyLock<ProgressStyle> = LazyLock::new(|| {
@@ -72,6 +75,8 @@ fn main() -> ExitCode {
 
     let cli = Ferium::parse();
 
+    let _ = rustls::crypto::ring::default_provider().install_default();
+
     let mut builder = tokio::runtime::Builder::new_multi_thread();
     builder.enable_all();
     builder.thread_name("ferium-worker");
@@ -138,6 +143,9 @@ async fn actual_main(mut cli_app: Ferium) -> Result<()> {
     if let Some(key) = cli_app.curseforge_api_key {
         set_var("CURSEFORGE_API_KEY", key);
     }
+    if let Some(n) = cli_app.parallel_network {
+        let _ = PARALLEL_NETWORK.set(n);
+    }
 
     let mut config_file = config::get_file(
         &cli_app

src/main.rs

@@ -2,7 +2,7 @@
 
 use crate::{
     download::{clean, download},
-    CROSS, STYLE_NO, TICK,
+    CROSS, DEFAULT_PARALLEL_NETWORK, PARALLEL_NETWORK, STYLE_NO, TICK,
 };
 use anyhow::{anyhow, bail, Result};
 use colored::Colorize as _;
@@ -34,7 +34,9 @@ pub async fn get_platform_downloadables(profile: &Profile) -> Result<(Vec<Downlo
     let mut tasks = FuturesUnordered::new();
 
     println!("{}\n", "Determining the Latest Compatible Versions".bold());
-    let semaphore = Arc::new(Semaphore::new(75));
+    let semaphore = Arc::new(Semaphore::new(
+        *PARALLEL_NETWORK.get_or_init(|| DEFAULT_PARALLEL_NETWORK),
+    ));
     progress_bar
         .lock()
         .expect("Mutex poisoned")
@@ -47,12 +49,12 @@ pub async fn get_platform_downloadables(profile: &Profile) -> Result<(Vec<Downlo
         .unwrap_or(20)
         .clamp(20, 50);
     for mod_ in profile.mods.clone() {
-        let permit = Arc::clone(&semaphore).acquire_owned().await?;
+        let semaphore = Arc::clone(&semaphore);
         let to_download = Arc::clone(&to_download);
         let progress_bar = Arc::clone(&progress_bar);
 
         tasks.push(async move {
-            let _permit = permit;
+            let _permit = semaphore.acquire_owned().await?;
             let result = mod_.fetch_download_file(profile.filters.clone()).await;
             let progress_bar = progress_bar.lock().expect("Mutex poisoned");
             progress_bar.inc(1);