Merge pull request #2740 from lann/factors-spin-http

factors: Implement spin outbound http

crates/factor-outbound-http/Cargo.toml

@@ -9,9 +9,11 @@ anyhow = "1.0"
 http = "1.1.0"
 http-body-util = "0.1"
 hyper = "1.4.1"
+reqwest = { version = "0.11", features = ["gzip"] }
 rustls = "0.23"
 spin-factor-outbound-networking = { path = "../factor-outbound-networking" }
 spin-factors = { path = "../factors" }
+spin-telemetry = { path = "../telemetry" }
 spin-world = { path = "../world" }
 terminal = { path = "../terminal" }
 tokio = { version = "1", features = ["macros", "rt"] }

crates/factor-outbound-http/src/lib.rs

@@ -71,6 +71,7 @@ impl Factor for OutboundHttpFactor {
             component_tls_configs,
             self_request_origin: None,
             request_interceptor: None,
+            spin_http_client: None,
         })
     }
 }
@@ -81,6 +82,8 @@ pub struct InstanceState {
     component_tls_configs: ComponentTlsConfigs,
     self_request_origin: Option<SelfRequestOrigin>,
     request_interceptor: Option<Box<dyn OutboundHttpInterceptor>>,
+    // Connection-pooling client for 'fermyon:spin/http' interface
+    spin_http_client: Option<reqwest::Client>,
 }
 
 impl InstanceState {
@@ -156,6 +159,12 @@ impl SelfRequestOrigin {
     }
 }
 
+impl std::fmt::Display for SelfRequestOrigin {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}://{}", self.scheme, self.authority)
+    }
+}
+
 /// An outbound HTTP request interceptor to be used with
 /// [`InstanceState::set_request_interceptor`].
 pub trait OutboundHttpInterceptor: Send + Sync {

crates/factor-outbound-http/src/spin.rs

@@ -1,24 +1,84 @@
 use spin_world::{
     async_trait,
-    v1::http,
-    v1::http_types::{self, HttpError, Request, Response},
+    v1::{
+        http as spin_http,
+        http_types::{self, HttpError, Method, Request, Response},
+    },
 };
+use tracing::{field::Empty, instrument, Level, Span};
 
 #[async_trait]
-impl http::Host for crate::InstanceState {
+impl spin_http::Host for crate::InstanceState {
+    #[instrument(name = "spin_outbound_http.send_request", skip_all, err(level = Level::INFO),
+        fields(otel.kind = "client", url.full = Empty, http.request.method = Empty,
+        http.response.status_code = Empty, otel.name = Empty, server.address = Empty, server.port = Empty))]
     async fn send_request(&mut self, req: Request) -> Result<Response, HttpError> {
-        // FIXME(lann): This is all just a stub to test allowed_outbound_hosts
-        match self.allowed_hosts.check_url(&req.uri, "https").await {
-            Ok(true) => (),
-            _ => {
+        let span = Span::current();
+        record_request_fields(&span, &req);
+
+        let uri = req.uri;
+        tracing::trace!("Sending outbound HTTP to {uri:?}");
+
+        let abs_url = if !uri.starts_with('/') {
+            // Absolute URI
+            let is_allowed = self
+                .allowed_hosts
+                .check_url(&uri, "https")
+                .await
+                .unwrap_or(false);
+            if !is_allowed {
+                return Err(HttpError::DestinationNotAllowed);
+            }
+            uri
+        } else {
+            // Relative URI ("self" request)
+            let is_allowed = self
+                .allowed_hosts
+                .check_relative_url(&["http", "https"])
+                .await
+                .unwrap_or(false);
+            if !is_allowed {
                 return Err(HttpError::DestinationNotAllowed);
             }
+
+            let Some(origin) = &self.self_request_origin else {
+                tracing::error!(
+                    "Couldn't handle outbound HTTP request to relative URI; no origin set"
+                );
+                return Err(HttpError::InvalidUrl);
+            };
+            format!("{origin}{uri}")
+        };
+        let req_url = reqwest::Url::parse(&abs_url).map_err(|_| HttpError::InvalidUrl)?;
+
+        if !req.params.is_empty() {
+            tracing::warn!("HTTP params field is deprecated");
         }
-        Ok(Response {
-            status: 200,
-            headers: None,
-            body: Some(b"test response".into()),
-        })
+
+        // Allow reuse of Client's internal connection pool for multiple requests
+        // in a single component execution
+        let client = self.spin_http_client.get_or_insert_with(Default::default);
+
+        let mut req = {
+            let mut builder = client.request(reqwest_method(req.method), req_url);
+            for (key, val) in req.headers {
+                builder = builder.header(key, val);
+            }
+            builder
+                .body(req.body.unwrap_or_default())
+                .build()
+                .map_err(|err| {
+                    tracing::error!("Error building outbound request: {err}");
+                    HttpError::RuntimeError
+                })?
+        };
+        spin_telemetry::inject_trace_context(req.headers_mut());
+
+        let resp = client.execute(req).await.map_err(log_reqwest_error)?;
+
+        tracing::trace!("Returning response from outbound request to {abs_url}");
+        span.record("http.response.status_code", resp.status().as_u16());
+        response_from_reqwest(resp).await
     }
 }
 
@@ -27,3 +87,93 @@ impl http_types::Host for crate::InstanceState {
         Ok(err)
     }
 }
+
+fn record_request_fields(span: &Span, req: &Request) {
+    let method = match req.method {
+        Method::Get => "GET",
+        Method::Post => "POST",
+        Method::Put => "PUT",
+        Method::Delete => "DELETE",
+        Method::Patch => "PATCH",
+        Method::Head => "HEAD",
+        Method::Options => "OPTIONS",
+    };
+    span.record("otel.name", method)
+        .record("http.request.method", method)
+        .record("url.full", req.uri.clone());
+    if let Ok(uri) = req.uri.parse::<http::Uri>() {
+        if let Some(authority) = uri.authority() {
+            span.record("server.address", authority.host());
+            if let Some(port) = authority.port() {
+                span.record("server.port", port.as_u16());
+            }
+        }
+    }
+}
+
+fn reqwest_method(m: Method) -> reqwest::Method {
+    match m {
+        Method::Get => reqwest::Method::GET,
+        Method::Post => reqwest::Method::POST,
+        Method::Put => reqwest::Method::PUT,
+        Method::Delete => reqwest::Method::DELETE,
+        Method::Patch => reqwest::Method::PATCH,
+        Method::Head => reqwest::Method::HEAD,
+        Method::Options => reqwest::Method::OPTIONS,
+    }
+}
+
+fn log_reqwest_error(err: reqwest::Error) -> HttpError {
+    let error_desc = if err.is_timeout() {
+        "timeout error"
+    } else if err.is_connect() {
+        "connection error"
+    } else if err.is_body() || err.is_decode() {
+        "message body error"
+    } else if err.is_request() {
+        "request error"
+    } else {
+        "error"
+    };
+    tracing::warn!(
+        "Outbound HTTP {}: URL {}, error detail {:?}",
+        error_desc,
+        err.url()
+            .map(|u| u.to_string())
+            .unwrap_or_else(|| "<unknown>".to_owned()),
+        err
+    );
+    HttpError::RuntimeError
+}
+
+async fn response_from_reqwest(res: reqwest::Response) -> Result<Response, HttpError> {
+    let status = res.status().as_u16();
+
+    let headers = res
+        .headers()
+        .into_iter()
+        .map(|(key, val)| {
+            Ok((
+                key.to_string(),
+                val.to_str()
+                    .map_err(|_| {
+                        tracing::error!("Non-ascii response header {key} = {val:?}");
+                        HttpError::RuntimeError
+                    })?
+                    .to_string(),
+            ))
+        })
+        .collect::<Result<Vec<_>, _>>()?;
+
+    let body = res
+        .bytes()
+        .await
+        .map_err(|_| HttpError::RuntimeError)?
+        .to_vec();
+
+    Ok(Response {
+        status,
+        headers: Some(headers),
+        body: Some(body),
+    })
+}

crates/factor-outbound-http/src/wasi.rs

@@ -86,6 +86,21 @@ impl<'a> WasiHttpView for WasiHttpImplInner<'a> {
         mut request: Request<wasmtime_wasi_http::body::HyperOutgoingBody>,
         mut config: wasmtime_wasi_http::types::OutgoingRequestConfig,
     ) -> wasmtime_wasi_http::HttpResult<wasmtime_wasi_http::types::HostFutureIncomingResponse> {
+        // wasmtime-wasi-http fills in scheme and authority for relative URLs
+        // (e.g. https://:443/<path>), which makes them hard to reason about.
+        // Undo that here.
+        let uri = request.uri_mut();
+        if uri
+            .authority()
+            .is_some_and(|authority| authority.host().is_empty())
+        {
+            let mut builder = http::uri::Builder::new();
+            if let Some(paq) = uri.path_and_query() {
+                builder = builder.path_and_query(paq.clone());
+            }
+            *uri = builder.build().unwrap();
+        }
+
         if let Some(interceptor) = &self.state.request_interceptor {
             match interceptor.intercept(&mut request, &mut config) {
                 InterceptOutcome::Continue => (),
@@ -149,6 +164,7 @@ async fn send_request_impl(
         config.use_tls = origin.use_tls();
 
         request.headers_mut().insert(HOST, origin.host_header());
+        spin_telemetry::inject_trace_context(&mut request);
 
         let path_and_query = request.uri().path_and_query().cloned();
         *request.uri_mut() = origin.into_uri(path_and_query);