fix(api-server): Preserve original host header for proxied API reques…

…ts (#10082)

Co-authored-by: Daniel Choudhury <[email protected]>

CHANGELOG.md

@@ -1,6 +1,8 @@
 # CHANGELOG
 
 ## Unreleased
+- fix(api-server): Preserve original host header for proxied API requests
+Some apps rely on reading the host header(eg multi-tenant apps served over multiple subdomains).  This change forwards on the original host header on proxied Fastify requests, and the experimental SSR/RSC server
 
 - fix(context): Re-export context from graphql-server (#10117)
 

packages/adapters/fastify/web/src/web.ts

@@ -31,6 +31,13 @@ export async function redwoodFastifyWeb(
       prefix: redwoodOptions.apiUrl,
       upstream: redwoodOptions.apiProxyTarget,
       disableCache: true,
+      replyOptions: {
+        rewriteRequestHeaders: (req, headers) => ({
+          ...headers,
+          // preserve the original host header, instead of letting it be overwritten by the proxy
+          host: req.headers.host,
+        }),
+      },
     })
   }