Sending compute type from the environment instead of hardcoded string (#1504)

# What does this PR do?

Sending compute type from the environment instead of hardcoded string

Using env is slow, therefore getting it from global state instead.

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Fixes # (issue)


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router/src/server.rs

@@ -57,6 +57,7 @@ example = json ! ({"error": "Incomplete generation"})),
 async fn compat_generate(
     Extension(default_return_full_text): Extension<bool>,
     infer: Extension<Infer>,
+    compute_type: Extension<ComputeType>,
     Json(mut req): Json<CompatGenerateRequest>,
 ) -> Result<Response, (StatusCode, Json<ErrorResponse>)> {
     // default return_full_text given the pipeline_tag
@@ -66,11 +67,11 @@ async fn compat_generate(
 
     // switch on stream
     if req.stream {
-        Ok(generate_stream(infer, Json(req.into()))
+        Ok(generate_stream(infer,compute_type,  Json(req.into()))
             .await
             .into_response())
     } else {
-        let (headers, Json(generation)) = generate(infer, Json(req.into())).await?;
+        let (headers, Json(generation)) = generate(infer, compute_type, Json(req.into())).await?;
         // wrap generation inside a Vec to match api-inference
         Ok((headers, Json(vec![generation])).into_response())
     }
@@ -145,6 +146,7 @@ seed,
 )]
 async fn generate(
     infer: Extension<Infer>,
+    Extension(ComputeType(compute_type)): Extension<ComputeType>,
     Json(req): Json<GenerateRequest>,
 ) -> Result<(HeaderMap, Json<GenerateResponse>), (StatusCode, Json<ErrorResponse>)> {
     let span = tracing::Span::current();
@@ -230,7 +232,7 @@ async fn generate(
 
     // Headers
     let mut headers = HeaderMap::new();
-    headers.insert("x-compute-type", "gpu+optimized".parse().unwrap());
+    headers.insert("x-compute-type", compute_type.parse().unwrap());
     headers.insert(
         "x-compute-time",
         total_time.as_millis().to_string().parse().unwrap(),
@@ -339,6 +341,7 @@ seed,
 )]
 async fn generate_stream(
     Extension(infer): Extension<Infer>,
+    Extension(compute_type): Extension<ComputeType>,
     Json(req): Json<GenerateRequest>,
 ) -> (
     HeaderMap,
@@ -349,13 +352,14 @@ async fn generate_stream(
         event.json_data(stream_token).unwrap()
     };
     let (headers, response_stream) =
-        generate_stream_internal(infer, Json(req), on_message_callback).await;
+        generate_stream_internal(infer, compute_type, Json(req), on_message_callback).await;
     let sse = Sse::new(response_stream).keep_alive(KeepAlive::default());
     (headers, sse)
 }
 
 async fn generate_stream_internal(
     infer: Infer,
+    ComputeType(compute_type): ComputeType,
     Json(req): Json<GenerateRequest>,
     on_message_callback: impl Fn(StreamResponse) -> Event,
 ) -> (HeaderMap, impl Stream<Item = Result<Event, Infallible>>) {
@@ -368,7 +372,7 @@ async fn generate_stream_internal(
     let compute_characters = req.inputs.chars().count();
 
     let mut headers = HeaderMap::new();
-    headers.insert("x-compute-type", "gpu+optimized".parse().unwrap());
+    headers.insert("x-compute-type",compute_type.parse().unwrap());
     headers.insert(
         "x-compute-characters",
         compute_characters.to_string().parse().unwrap(),
@@ -557,6 +561,7 @@ async fn generate_stream_internal(
     )]
 async fn chat_completions(
     Extension(infer): Extension<Infer>,
+    Extension(compute_type): Extension<ComputeType>,
     Extension(info): Extension<Info>,
     Json(req): Json<ChatRequest>,
 ) -> Result<Response, (StatusCode, Json<ErrorResponse>)> {
@@ -645,12 +650,12 @@ async fn chat_completions(
         };
 
         let (headers, response_stream) =
-            generate_stream_internal(infer, Json(generate_request), on_message_callback).await;
+            generate_stream_internal(infer, compute_type, Json(generate_request), on_message_callback).await;
         let sse = Sse::new(response_stream).keep_alive(KeepAlive::default());
         Ok((headers, sse).into_response())
     } else {
         let (headers, Json(generation)) =
-            generate(Extension(infer), Json(generate_request)).await?;
+            generate(Extension(infer), Extension(compute_type), Json(generate_request)).await?;
 
         let current_time = std::time::SystemTime::now()
             .duration_since(std::time::UNIX_EPOCH)
@@ -729,6 +734,9 @@ async fn metrics(prom_handle: Extension<PrometheusHandle>) -> String {
     prom_handle.render()
 }
 
+#[derive(Clone, Debug)]
+pub(crate) struct ComputeType(String);
+
 /// Serving method
 #[allow(clippy::too_many_arguments)]
 pub async fn run(
@@ -935,6 +943,8 @@ pub async fn run(
         Router::new().route("/invocations", post(compat_generate)) // Use 'compat_generate' otherwise
     };
 
+    let compute_type = ComputeType(std::env::var("COMPUTE_TYPE").unwrap_or("gpu+optimized".to_string()));
+
     // Combine routes and layers
     let app = Router::new()
         .merge(swagger_ui)
@@ -944,6 +954,7 @@ pub async fn run(
         .layer(Extension(health_ext.clone()))
         .layer(Extension(compat_return_full_text))
         .layer(Extension(infer))
+        .layer(Extension(compute_type))
         .layer(Extension(prom_handle.clone()))
         .layer(OtelAxumLayer::default())
         .layer(cors_layer);