Return the appropriate HTTP status on client errors

1 files changed, 19 insertions, 11 deletions

diff --git a/guix-build-coordinator/client-communication.scm b/guix-build-coordinator/client-communication.scm
index d732f9f..c98d403 100644
--- a/guix-build-coordinator/client-communication.scm
+++ b/guix-build-coordinator/client-communication.scm
@@ -603,21 +603,29 @@
 
   (with-exception-handler
       (lambda (exn)
-        (render-json
-         `((error . 500))
-         #:code 500))
+        (cond
+         ((client-error? exn)
+          (render-json
+           `((error . ,(client-error-details exn)))
+           #:code 400))
+         (else
+          (render-json
+           `((error . 500))
+           #:code 500))))
     (lambda ()
       (with-throw-handler #t
         controller-thunk
         (lambda (key . args)
-          (match method-and-path-components
-            ((method path-components ...)
-             (simple-format
-              (current-error-port)
-              "error: when processing client request: /~A ~A\n  ~A ~A\n"
-              method (string-join path-components "/")
-              key args)))
-          (backtrace))))
+          (unless (and (eq? '%exception key)
+                       (client-error? (car args)))
+            (match method-and-path-components
+              ((method path-components ...)
+               (simple-format
+                (current-error-port)
+                "error: when processing client request: /~A ~A\n  ~A ~A\n"
+                method (string-join path-components "/")
+                key args)))
+            (backtrace)))))
     #:unwind? #t))
 
 (define* (render-json json #:key (extra-headers '())