feat: use clap to handle args and env vars

closes #2

Cargo.toml

@@ -8,6 +8,13 @@ description = "bwHC MTB-File REST Proxy für Kafka"
 
 # Dependencies
 
+[dependencies.clap]
+version = "4.5"
+features = ["derive", "env"]
+
+[dependencies.lazy_static]
+version = "1.4"
+
 [dependencies.log]
 version = "0.4"
 

README.md

@@ -13,7 +13,21 @@ Verwendung im Zusammenspiel mit https://github.com/CCC-MF/etl-processor
 
 ## Konfiguration
 
-Die Anwendung lässt sich mit Umgebungsvariablen konfigurieren.
+Beim Start der Anwendung können Parameter angegeben werden.
+
+```
+Usage: bwhc-kafka-rest-proxy [OPTIONS] --token <TOKEN>
+
+Options:
+      --bootstrap-server <BOOTSTRAP_SERVER>
+          Kafka Bootstrap-Server(s) [env: KAFKA_BOOTSTRAP_SERVERS=] [default: kafka:9094]
+      --topic <TOPIC>
+          Kafka Topic [env: APP_KAFKA_TOPIC=] [default: etl-processor_input]
+      --token <TOKEN>
+          bcrypt hashed Security Token [env: APP_SECURITY_TOKEN=]
+```
+
+Die Anwendung lässt sich auch mit Umgebungsvariablen konfigurieren.
 
 * `APP_KAFKA_SERVERS`: Zu verwendende Kafka-Bootstrap-Server als kommagetrennte Liste
 * `APP_KAFKA_TOPIC`: Zu verwendendes Topic zum Warten auf neue Anfragen. Standardwert: `etl-processor_input`
@@ -81,10 +95,10 @@ Resultierender Kafka-Record:
 
 #### Löschen von Patienten
 
-Anfrage auch hier mit **curl**:
+Anfrage auch hier mit *curl*:
 
 ```bash
-curl -v -u token:very-secret \
+curl -u token:very-secret \
   -H "Content-Type: application/json" \
   -X DELETE \
   http://localhost:3000/mtbfile/P1
@@ -112,4 +126,4 @@ In optionaler Verbindung mit [Key-Based-Retention](https://github.com/CCC-MF/etl
 letzte und aktuelle Record, hier die Information eines Consent-Widerspruchs, in Kafka vorgehalten.
 
 Trifft dieser Kafka-Record im [ETL-Prozessor](https://github.com/CCC-MF/etl-processor) ein, so wird dort ebenfalls eine
-Löschanfrage ausgelöst, da der Consent-Status den Wert `rejected` hat.
+Löschanfrage ausgelöst, da der Consent-Status den Wert `rejected` hat.

src/cli.rs

@@ -0,0 +1,30 @@
+use clap::Parser;
+
+#[derive(Parser)]
+#[command(author, version, about)]
+#[command(arg_required_else_help(true))]
+pub struct Cli {
+    #[arg(
+        long,
+        alias = "kafka-servers",
+        env = "APP_KAFKA_SERVERS",
+        default_value = "kafka:9094",
+        help = "Kafka Bootstrap Server"
+    )]
+    pub bootstrap_server: String,
+    #[arg(
+        long,
+        alias = "kafka-topic",
+        env = "APP_KAFKA_TOPIC",
+        default_value = "etl-processor_input",
+        help = "Kafka Topic"
+    )]
+    pub topic: String,
+    #[arg(
+        long,
+        alias = "security-token",
+        env = "APP_SECURITY_TOKEN",
+        help = "bcrypt hashed Security Token"
+    )]
+    pub token: String,
+}

src/main.rs

@@ -1,24 +1,28 @@
-use std::env;
 use std::time::Duration;
 
+use axum::{Extension, Json, Router};
 use axum::body::Body;
 use axum::extract::Path;
-use axum::http::header::AUTHORIZATION;
 use axum::http::{Request, StatusCode};
+use axum::http::header::AUTHORIZATION;
 use axum::middleware::{from_fn, Next};
 use axum::response::Response;
 use axum::routing::{delete, post};
-use axum::{Extension, Json, Router};
 use bwhc_dto::MtbFile;
+use clap::Parser;
+use lazy_static::lazy_static;
+use rdkafka::ClientConfig;
 use rdkafka::message::{Header, OwnedHeaders};
 use rdkafka::producer::{FutureProducer, FutureRecord};
-use rdkafka::ClientConfig;
 use serde::{Deserialize, Serialize};
 #[cfg(debug_assertions)]
 use tower_http::trace::TraceLayer;
 use uuid::Uuid;
 
+use crate::cli::Cli;
+
 mod auth;
+mod cli;
 
 #[derive(Serialize, Deserialize)]
 struct RecordKey {
@@ -26,10 +30,12 @@ struct RecordKey {
     patient_id: String,
 }
 
+lazy_static! {
+    static ref CONFIG: Cli = Cli::parse();
+}
+
 #[tokio::main]
 async fn main() {
-    let _ = bcrypt_hashed_token();
-
     #[cfg(debug_assertions)]
     {
         tracing_subscriber::fmt()
@@ -37,10 +43,8 @@ async fn main() {
             .init();
     }
 
-    let boostrap_servers = env::var("KAFKA_BOOTSTRAP_SERVERS").unwrap_or("kafka:9094".into());
-
     let producer: FutureProducer = ClientConfig::new()
-        .set("bootstrap.servers", boostrap_servers.as_str())
+        .set("bootstrap.servers", CONFIG.bootstrap_server.as_str())
         .set("message.timeout.ms", "5000")
         .create()
         .expect("Producer creation error");
@@ -60,7 +64,7 @@ async fn main() {
 
 async fn check_basic_auth(request: Request<Body>, next: Next) -> Response {
     if let Some(Ok(auth_header)) = request.headers().get(AUTHORIZATION).map(|x| x.to_str()) {
-        if auth::check_basic_auth(auth_header, &bcrypt_hashed_token()) {
+        if auth::check_basic_auth(auth_header, &CONFIG.token) {
             return next.run(request).await;
         }
     }
@@ -76,7 +80,7 @@ async fn handle_delete(
 ) -> Response {
     let delete_mtb_file = MtbFile::new_with_consent_rejected(&patient_id);
 
-    match send_mtb_file(producer, &dst_topic(), delete_mtb_file).await {
+    match send_mtb_file(producer, &CONFIG.topic, delete_mtb_file).await {
         Ok(request_id) => success_response(&request_id),
         _ => error_response(),
     }
@@ -86,7 +90,7 @@ async fn handle_post(
     Extension(producer): Extension<FutureProducer>,
     Json(mtb_file): Json<MtbFile>,
 ) -> Response {
-    match send_mtb_file(producer, &dst_topic(), mtb_file).await {
+    match send_mtb_file(producer, &CONFIG.topic, mtb_file).await {
         Ok(request_id) => success_response(&request_id),
         _ => error_response(),
     }
@@ -143,13 +147,3 @@ fn error_response() -> Response {
         .body(Body::empty())
         .expect("response built")
 }
-
-fn dst_topic() -> String {
-    env::var("APP_KAFKA_TOPIC").unwrap_or("etl-processor_input".into())
-}
-
-fn bcrypt_hashed_token() -> String {
-    env::var("APP_SECURITY_TOKEN").unwrap_or_else(|_| {
-        panic!("Missing configuration 'APP_SECURITY_TOKEN'. Provide bcrypt hashed token value.")
-    })
-}