Refactor OpenAPI routes and add new handlers for documentation endpoints (#282)

* Refactor OpenAPI routes and add new handlers for documentation endpoints

- Updated the main application to integrate the OpenAPI router.
- Added handlers for OpenAPI JSON, ReDoc, and Scalar documentation endpoints in `openapi.rs`.
- Improved error handling for HTTP responses in the new handlers.
- Cleaned up code formatting in `main.rs` for better readability.

* fix compiler warnings

Author: omer9564

pdp-server/src/main.rs

@@ -15,7 +15,6 @@ use log::{error, info};
 use std::net::SocketAddr;
 use utoipa::OpenApi;
 use utoipa_axum::router::OpenApiRouter;
-use utoipa_scalar::{Scalar, Servable};
 
 #[tokio::main]
 async fn main() {
@@ -39,7 +38,6 @@ async fn main() {
             std::process::exit(1);
         }
     };
-
     // Initialize application state
     let state: AppState = AppState::with_existing_cache(&config, cache)
         .await
@@ -78,14 +76,13 @@ async fn main() {
 /// Create a new application instance with a given state
 pub async fn create_app(state: AppState) -> Router {
     // Create OpenAPI documentation
-    let (openapi_router, api_doc) =
-        OpenApiRouter::with_openapi(openapi::ApiDoc::openapi()).split_for_parts();
+    let openapi_router = OpenApiRouter::with_openapi(openapi::ApiDoc::openapi());
 
     // Create base router with routes
     Router::new()
         .merge(api::router(&state))
         .merge(openapi_router)
-        .merge(Scalar::with_url("/scalar", api_doc.clone()))
+        .merge(crate::openapi::router())
         .with_state(state)
 }
 

pdp-server/src/openapi.rs

@@ -1,3 +1,9 @@
+use crate::state::AppState;
+use axum::body::Body;
+use axum::http::StatusCode;
+use axum::response::{IntoResponse, Response};
+use axum::{extract::State, routing::get, Router};
+use http::HeaderValue;
 use utoipa::OpenApi;
 
 pub(crate) const HEALTH_TAG: &str = "Health API";
@@ -17,3 +23,95 @@ pub(crate) const AUTHZEN_TAG: &str = "AuthZen API";
     )
 )]
 pub(crate) struct ApiDoc;
+
+/// Handler for the OpenAPI JSON specification endpoint
+async fn openapi_json_handler(State(state): State<AppState>) -> impl IntoResponse {
+    let openapi_url = state.config.horizon.get_url("/openapi.json");
+
+    match state.horizon_client.get(&openapi_url).send().await {
+        Ok(response) => match response.bytes().await {
+            Ok(bytes) => match serde_json::from_slice::<serde_json::Value>(&bytes) {
+                Ok(json) => axum::Json(json).into_response(),
+                Err(_) => (StatusCode::INTERNAL_SERVER_ERROR, "Invalid JSON").into_response(),
+            },
+            Err(_) => {
+                (StatusCode::INTERNAL_SERVER_ERROR, "Failed to read response").into_response()
+            }
+        },
+        Err(_) => (
+            StatusCode::SERVICE_UNAVAILABLE,
+            "Horizon service unavailable",
+        )
+            .into_response(),
+    }
+}
+
+/// Handler for the ReDoc documentation endpoint
+async fn redoc_handler(State(state): State<AppState>) -> impl IntoResponse {
+    let redoc_url = state.config.horizon.get_url("/redoc");
+
+    match state.horizon_client.get(&redoc_url).send().await {
+        Ok(response) => {
+            // Extract content-type header before consuming the response
+            let content_type = response
+                .headers()
+                .get("content-type")
+                .unwrap_or(&HeaderValue::from_static("text/html"))
+                .clone();
+
+            match response.text().await {
+                Ok(text) => Response::builder()
+                    .header("content-type", content_type)
+                    .body(Body::from(text))
+                    .unwrap(),
+                Err(_) => {
+                    (StatusCode::INTERNAL_SERVER_ERROR, "Failed to read response").into_response()
+                }
+            }
+        }
+        Err(_) => (
+            StatusCode::SERVICE_UNAVAILABLE,
+            "Horizon service unavailable",
+        )
+            .into_response(),
+    }
+}
+
+/// Handler for the Scalar documentation endpoint
+async fn scalar_handler(State(state): State<AppState>) -> impl IntoResponse {
+    let scalar_url = state.config.horizon.get_url("/scalar");
+
+    match state.horizon_client.get(&scalar_url).send().await {
+        Ok(response) => {
+            // Extract content-type header before consuming the response
+            let content_type = response
+                .headers()
+                .get("content-type")
+                .unwrap_or(&HeaderValue::from_static("text/html"))
+                .clone();
+
+            match response.text().await {
+                Ok(res_text) => Response::builder()
+                    .header("content-type", content_type)
+                    .body(Body::from(res_text))
+                    .unwrap(),
+                Err(_) => {
+                    (StatusCode::INTERNAL_SERVER_ERROR, "Failed to read response").into_response()
+                }
+            }
+        }
+        Err(_) => (
+            StatusCode::SERVICE_UNAVAILABLE,
+            "Horizon service unavailable",
+        )
+            .into_response(),
+    }
+}
+
+/// Creates a router for OpenAPI documentation routes
+pub(crate) fn router() -> Router<AppState> {
+    Router::new()
+        .route("/openapi.json", get(openapi_json_handler))
+        .route("/redoc", get(redoc_handler))
+        .route("/scalar", get(scalar_handler))
+}