From 7a370b50d75a20253f82ae005761c947000d45e2 Mon Sep 17 00:00:00 2001
From: Pedro Martin <pataruco@gmail.com>
Date: Tue, 19 Dec 2023 16:31:15 +0000
Subject: [PATCH] Draft handller for POST /order

---
 .../order-service/src/api/handlers.rs         | 63 +++++++++++++++++++
 .../order-service/src/api/server.rs           | 34 ++++++----
 rust-containers-k8s/order-service/src/main.rs | 10 ++-
 3 files changed, 92 insertions(+), 15 deletions(-)
 create mode 100644 rust-containers-k8s/order-service/src/api/handlers.rs

diff --git a/rust-containers-k8s/order-service/src/api/handlers.rs b/rust-containers-k8s/order-service/src/api/handlers.rs
new file mode 100644
index 0000000..83f9034
--- /dev/null
+++ b/rust-containers-k8s/order-service/src/api/handlers.rs
@@ -0,0 +1,63 @@
+use super::server::AppState;
+use crate::api::types::{InventoryResponse, OrderRequest};
+use axum::{debug_handler, extract::State, http::StatusCode, Json};
+use std::sync::Arc;
+
+pub async fn root() -> &'static str {
+    "Hello, World!"
+}
+
+pub async fn get_orders() -> &'static str {
+    "Hello, World!"
+}
+
+#[debug_handler]
+pub async fn create_order(
+    State(state): State<Arc<AppState>>,
+    Json(payload): Json<OrderRequest>,
+) -> Result<(), (StatusCode, String)> {
+    let query: Vec<(String, String)> = payload
+        .items
+        .iter()
+        .map(|i| ("sku".to_string(), i.sku.clone()))
+        .collect();
+    //  call inventory service;
+    // takes a request of a list of order line items, checks they are all in stock (http call to the inventory service) and if so, creates an order entry in the database
+    let client = reqwest::Client::new();
+    let all_in_stock = client
+        // TODO: update this url
+        .get("http://inventory-service/api/inventory")
+        .query(&query)
+        .send()
+        .await
+        .map_err(internal_error)?
+        .json::<Vec<InventoryResponse>>()
+        .await
+        .map_err(internal_error)?
+        .iter()
+        .all(|i| i.is_in_stock);
+
+    if all_in_stock {
+        // TODO: Update SQL  query
+        let row: (i64,) = sqlx::query_as("INSERT into sometable values ($1)")
+            .bind(150_i64)
+            .fetch_one(&state.pool)
+            .await
+            .map_err(internal_error)?;
+    }
+
+    Ok(())
+}
+
+/// Utility function for mapping any error into a `500 Internal Server Error`
+/// response.
+fn internal_error<E>(err: E) -> (StatusCode, String)
+where
+    E: std::error::Error,
+{
+    (StatusCode::INTERNAL_SERVER_ERROR, err.to_string())
+}
+
+pub async fn health() -> &'static str {
+    "ok"
+}
diff --git a/rust-containers-k8s/order-service/src/api/server.rs b/rust-containers-k8s/order-service/src/api/server.rs
index b52ff3e..da0d3af 100644
--- a/rust-containers-k8s/order-service/src/api/server.rs
+++ b/rust-containers-k8s/order-service/src/api/server.rs
@@ -1,21 +1,29 @@
-use axum::{routing::get, Router};
-
+use crate::api::handlers::{create_order, get_orders, health, root};
 use crate::config::Config;
+use axum::{routing::get, routing::post, Router};
+use sqlx::{Pool, Postgres};
+use std::sync::Arc;
+
+pub struct AppState {
+    pub pool: Pool<Postgres>,
+}
+
+pub async fn create(config: Config, pool: Pool<Postgres>) -> anyhow::Result<()> {
+    let state = Arc::new(AppState { pool });
 
-pub async fn create(config: Config) {
     // build our application with a route
-    let app = Router::new().route("/", get(root));
+    let app = Router::new()
+        .route("/", get(root))
+        .route("/health", get(health))
+        .route("/api/order", get(get_orders))
+        .route("/api/order", post(create_order))
+        .with_state(state);
 
     // run it
     //todo pass a port
-    let listener = tokio::net::TcpListener::bind(format!("127.0.0.1:{}", config.port))
-        .await
-        .unwrap();
-    println!("listening on {}", listener.local_addr().unwrap());
-    axum::serve(listener, app).await.unwrap();
-}
+    let listener = tokio::net::TcpListener::bind(format!("127.0.0.1:{}", config.port)).await?;
+    println!("listening on {}", listener.local_addr()?);
+    axum::serve(listener, app).await?;
 
-// basic handler that responds with a static string
-async fn root() -> &'static str {
-    "Hello, World!"
+    Ok(())
 }
diff --git a/rust-containers-k8s/order-service/src/main.rs b/rust-containers-k8s/order-service/src/main.rs
index 101b783..cf77b4b 100644
--- a/rust-containers-k8s/order-service/src/main.rs
+++ b/rust-containers-k8s/order-service/src/main.rs
@@ -1,5 +1,6 @@
 use dotenv::dotenv;
 use order_service::{api::server, config::Config};
+use sqlx::postgres::PgPoolOptions;
 
 #[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
@@ -8,7 +9,12 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
 
     println!("{:?}", config);
 
-    server::create(config).await;
+    let pool = PgPoolOptions::new()
+        .max_connections(5)
+        // TODO: paramterise this
+        .connect("postgres://commerce:commerce@localhost/order-service")
+        .await?;
+
+    server::create(config, pool).await?;
     Ok(())
 }
-