Fix cache-control header for 404 requests (#1169)

Author: ije

server/router.go

@@ -1467,7 +1467,7 @@ func esmRouter(db Database, buildStorage storage.Storage, logger *log.Logger) re
 				case output := <-ch:
 					if output.err != nil {
 						if output.err.Error() == "types not found" {
-							ctx.SetHeader("Cache-Control", ccImmutable)
+							ctx.SetHeader("Cache-Control", fmt.Sprintf("public, max-age=%d", config.NpmQueryCacheTTL))
 							return rex.Status(404, "Types Not Found")
 						}
 						return rex.Status(500, "Failed to build types: "+output.err.Error())
@@ -1583,11 +1583,7 @@ func esmRouter(db Database, buildStorage storage.Storage, logger *log.Logger) re
 				if output.err != nil {
 					msg := output.err.Error()
 					if msg == "could not resolve build entry" || strings.HasSuffix(msg, " not found") || strings.Contains(msg, "is not exported from package") || strings.Contains(msg, "no such file or directory") {
-						if strings.HasPrefix(msg, "version ") && strings.HasSuffix(msg, " not found") {
-							ctx.SetHeader("Cache-Control", fmt.Sprintf("public, max-age=%d", config.NpmQueryCacheTTL))
-						} else {
-							ctx.SetHeader("Cache-Control", ccImmutable)
-						}
+						ctx.SetHeader("Cache-Control", fmt.Sprintf("public, max-age=%d", config.NpmQueryCacheTTL))
 						return rex.Status(404, msg)
 					}
 					return rex.Status(500, msg)