Can specify environment variables in client configuration

Cargo.lock

@@ -421,6 +421,7 @@ dependencies = [
  "futures-util",
  "include_dir",
  "jwt-simple",
+ "lazy-regex",
  "log",
  "mime_guess",
  "rand",
@@ -1211,6 +1212,29 @@ version = "0.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d4345964bb142484797b161f473a503a434de77149dd8c7427788c6e13379388"
 
+[[package]]
+name = "lazy-regex"
+version = "2.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b6b12f2eb6ed7d39405c5eb25a034b4c106a9ad87a6d9be3298de6c5f32fd57d"
+dependencies = [
+ "lazy-regex-proc_macros",
+ "once_cell",
+ "regex",
+]
+
+[[package]]
+name = "lazy-regex-proc_macros"
+version = "2.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f2496e5264069bc726ccf37eb76b9cd89406ae110d836c3f76729f99c8a23293"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "regex",
+ "syn",
+]
+
 [[package]]
 name = "lazy_static"
 version = "1.4.0"

Cargo.toml

@@ -26,4 +26,5 @@ rand = "0.8.5"
 base64 = "0.13.0"
 jwt-simple = "0.10.9"
 digest = "0.10.3"
-sha2 = "0.10.2"
+sha2 = "0.10.2"
+lazy-regex = "2.3.0"

src/data/client.rs

@@ -1,4 +1,5 @@
 use crate::data::entity_manager::EntityManager;
+use crate::utils::string_utils::apply_env_vars;
 
 #[derive(Clone, Debug, serde::Serialize, serde::Deserialize, Eq, PartialEq)]
 pub struct ClientID(pub String);
@@ -32,4 +33,14 @@ impl EntityManager<Client> {
         }
         None
     }
+
+    pub fn apply_environment_variables(&mut self) {
+        for c in self.iter_mut() {
+            c.id = ClientID(apply_env_vars(&c.id.0));
+            c.name = apply_env_vars(&c.name);
+            c.description = apply_env_vars(&c.description);
+            c.secret = apply_env_vars(&c.secret);
+            c.redirect_uri = apply_env_vars(&c.redirect_uri);
+        }
+    }
 }

src/data/entity_manager.rs

@@ -1,5 +1,5 @@
 use std::path::{Path, PathBuf};
-use std::slice::Iter;
+use std::slice::{Iter, IterMut};
 
 use crate::utils::err::Res;
 
@@ -87,6 +87,11 @@ impl<E> EntityManager<E>
         self.list.iter()
     }
 
+    /// Iterate over the entries of this entity manager
+    pub fn iter_mut(&mut self) -> IterMut<'_, E> {
+        self.list.iter_mut()
+    }
+
     /// Get a cloned list of entries
     pub fn cloned(&self) -> Vec<E> {
         self.list.clone()

src/main.rs

@@ -74,8 +74,9 @@ async fn main() -> std::io::Result<()> {
     let listen_address = config.listen_address.to_string();
 
     HttpServer::new(move || {
-        let clients = ClientManager::open_or_create(config.clients_file())
+        let mut clients = ClientManager::open_or_create(config.clients_file())
             .expect("Failed to load clients list!");
+        clients.apply_environment_variables();
 
         let policy = CookieIdentityPolicy::new(config.token_key.as_bytes())
             .name(SESSION_COOKIE_NAME)

src/utils/string_utils.rs

@@ -1,3 +1,4 @@
+use lazy_regex::regex_find;
 use rand::distributions::Alphanumeric;
 use rand::Rng;
 
@@ -9,3 +10,24 @@ pub fn rand_str(len: usize) -> String {
         .take(len)
         .collect()
 }
+
+/// Parse environment variables
+pub fn apply_env_vars(val: &str) -> String {
+    let mut val = val.to_string();
+
+    if let Some(varname_with_wrapper) = regex_find!(r#"\$\{[a-zA-Z0-9_-]+\}"#, &val) {
+        let varname = varname_with_wrapper.strip_prefix("${").unwrap().strip_suffix('}').unwrap();
+        let value = match std::env::var(varname) {
+            Ok(v) => v,
+            Err(e) => {
+                log::error!("Failed to find environment variable {}!", varname);
+                eprintln!("Failed to find environment variable! {:?}", e);
+                std::process::exit(2);
+            }
+        };
+
+        val = val.replace(varname_with_wrapper, &value);
+    }
+
+    val
+}