feat(api): init rust rewrite

lib/libpk/src/_config.rs

@@ -0,0 +1,50 @@
+use config::Config;
+use lazy_static::lazy_static;
+use serde::Deserialize;
+use std::sync::Arc;
+
+#[derive(Deserialize, Debug)]
+pub struct DiscordConfig {
+    pub client_id: u32,
+    pub bot_token: String,
+    pub client_secret: String,
+}
+
+#[derive(Deserialize, Debug)]
+pub struct DatabaseConfig {
+    pub(crate) _data_db_uri: String,
+    pub(crate) _messages_db_uri: String,
+    pub(crate) _db_password: Option<String>,
+    pub data_redis_addr: String,
+}
+
+fn _default_api_addr() -> String {
+    "0.0.0.0:5000".to_string()
+}
+
+#[derive(Deserialize, Debug)]
+pub struct ApiConfig {
+    #[serde(default = "_default_api_addr")]
+    pub addr: String,
+
+    #[serde(default)]
+    pub ratelimit_redis_addr: Option<String>,
+
+    pub remote_url: String,
+}
+
+#[derive(Deserialize, Debug)]
+pub struct PKConfig {
+    pub discord: DiscordConfig,
+    pub api: ApiConfig,
+
+    pub(crate) gelf_log_url: Option<String>,
+}
+
+lazy_static! {
+    #[derive(Debug)]
+    pub static ref CONFIG: Arc<PKConfig> = Arc::new(Config::builder()
+    .add_source(config::Environment::with_prefix("pluralkit").separator("__"))
+    .build().unwrap()
+    .try_deserialize::<PKConfig>().unwrap());
+}