From aa81c7f97976806a6f819d90634527039eee037c Mon Sep 17 00:00:00 2001
From: Pierre Hubert <pierre.git@communiquons.org>
Date: Tue, 19 Dec 2023 23:23:19 +0100
Subject: [PATCH] Improve app arguments management, can specify env file

---
 virtweb_backend/Cargo.lock        |  7 +++++
 virtweb_backend/Cargo.toml        |  1 +
 virtweb_backend/src/app_config.rs | 44 ++++++++++++++++++++++++++-----
 virtweb_backend/src/main.rs       |  3 +++
 4 files changed, 48 insertions(+), 7 deletions(-)

diff --git a/virtweb_backend/Cargo.lock b/virtweb_backend/Cargo.lock
index a984526..4cadb48 100644
--- a/virtweb_backend/Cargo.lock
+++ b/virtweb_backend/Cargo.lock
@@ -918,6 +918,12 @@ dependencies = [
  "subtle",
 ]
 
+[[package]]
+name = "dotenvy"
+version = "0.15.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1aaf95b3e5c8f23aa320147307562d361db0ae0d51242340f558153b4eb2439b"
+
 [[package]]
 name = "either"
 version = "1.9.0"
@@ -2644,6 +2650,7 @@ dependencies = [
  "anyhow",
  "bytes",
  "clap",
+ "dotenvy",
  "env_logger",
  "futures",
  "futures-util",
diff --git a/virtweb_backend/Cargo.toml b/virtweb_backend/Cargo.toml
index 2d096bf..03746f2 100644
--- a/virtweb_backend/Cargo.toml
+++ b/virtweb_backend/Cargo.toml
@@ -43,3 +43,4 @@ ipnetwork = "0.20.0"
 num = "0.4.1"
 rust-embed = { version = "8.1.0" }
 mime_guess = "2.0.4"
+dotenvy = "0.15.7"
\ No newline at end of file
diff --git a/virtweb_backend/src/app_config.rs b/virtweb_backend/src/app_config.rs
index 2afb8fa..4ce9bea 100644
--- a/virtweb_backend/src/app_config.rs
+++ b/virtweb_backend/src/app_config.rs
@@ -8,6 +8,10 @@ use std::str::FromStr;
 #[derive(Parser, Debug, Clone)]
 #[clap(author, version, about, long_about = None)]
 pub struct AppConfig {
+    /// Read arguments from env file
+    #[clap(short, long, env)]
+    pub config: Option<String>,
+
     /// Listen address
     #[clap(short, long, env, default_value = "0.0.0.0:8000")]
     pub listen_address: String,
@@ -20,7 +24,7 @@ pub struct AppConfig {
     ///
     /// Warning! These origins won't be usable for OpenID authentication,
     /// only for local auth
-    #[clap(long, env)]
+    #[clap(short = 'o', long, env)]
     pub additional_origins: Vec<String>,
 
     /// Proxy IP, might end with a star "*"
@@ -28,7 +32,7 @@ pub struct AppConfig {
     pub proxy_ip: Option<String>,
 
     /// Secret key, used to sign some resources. Must be randomly generated
-    #[clap(long, env, default_value = "")]
+    #[clap(short = 'S', long, env, default_value = "")]
     secret: String,
 
     /// Specify whether the cookie should be transmitted only over secure connections
@@ -36,11 +40,11 @@ pub struct AppConfig {
     pub cookie_secure: bool,
 
     /// Auth username
-    #[arg(long, env, default_value = "admin")]
+    #[arg(short = 'u', long, env, default_value = "admin")]
     pub auth_username: String,
 
     /// Auth password
-    #[arg(long, env, default_value = "admin")]
+    #[arg(short = 'P', long, env, default_value = "admin")]
     pub auth_password: String,
 
     /// Disable authentication WARNING! THIS IS UNSECURE, it was designed only for development
@@ -88,16 +92,16 @@ pub struct AppConfig {
     ///
     /// Warning! This directory MUST be changed if `/tmp` is not in the same disk as the storage
     /// directory!
-    #[arg(long, env, default_value = "/tmp")]
+    #[arg(short, long, env, default_value = "/tmp")]
     pub temp_dir: String,
 
     /// Hypervisor URI. If not specified, "" will be used instead
-    #[arg(long, env)]
+    #[arg(short = 'H', long, env)]
     pub hypervisor_uri: Option<String>,
 
     /// Trusted network. If set, a client from a different will not be able to perform request other
     /// than those with GET verb (aside for login)
-    #[arg(long, env)]
+    #[arg(short = 'T', long, env)]
     pub trusted_network: Vec<String>,
 }
 
@@ -108,6 +112,21 @@ lazy_static::lazy_static! {
 }
 
 impl AppConfig {
+    /// Parse environment variables from file, if requedst
+    pub fn parse_env_file() -> anyhow::Result<()> {
+        if let Some(c) = Self::parse().config {
+            log::info!("Load additional environment variables from {c}");
+            let conf_file = Path::new(&c);
+
+            if !conf_file.is_file() {
+                panic!("Specified configuration is not a file!");
+            }
+            dotenvy::from_path(conf_file)?;
+        }
+
+        Ok(())
+    }
+
     /// Get parsed command line arguments
     pub fn get() -> &'static AppConfig {
         &ARGS
@@ -227,3 +246,14 @@ pub struct OIDCProvider<'a> {
     #[serde(skip_serializing)]
     pub configuration_url: &'a str,
 }
+
+#[cfg(test)]
+mod test {
+    use crate::app_config::AppConfig;
+
+    #[test]
+    fn verify_cli() {
+        use clap::CommandFactory;
+        AppConfig::command().debug_assert()
+    }
+}
diff --git a/virtweb_backend/src/main.rs b/virtweb_backend/src/main.rs
index 401f0d4..00522ff 100644
--- a/virtweb_backend/src/main.rs
+++ b/virtweb_backend/src/main.rs
@@ -33,6 +33,9 @@ use virtweb_backend::utils::files_utils;
 async fn main() -> std::io::Result<()> {
     env_logger::init_from_env(env_logger::Env::new().default_filter_or("info"));
 
+    // Load additional config from file, if requested
+    AppConfig::parse_env_file().unwrap();
+
     log::debug!("Create required directory, if missing");
     files_utils::create_directory_if_missing(AppConfig::get().iso_storage_path()).unwrap();
     files_utils::create_directory_if_missing(AppConfig::get().vnc_sockets_path()).unwrap();