Refactor the fibers server starting code

More clearly split out the things that need to happen prior to run-fibers, and
the things that can happen after.

1 files changed, 35 insertions, 36 deletions

diff --git a/scripts/guix-build-coordinator.in b/scripts/guix-build-coordinator.in
index c7fbb1a..71111c0 100644
--- a/scripts/guix-build-coordinator.in
+++ b/scripts/guix-build-coordinator.in
@@ -467,51 +467,50 @@ processed?:      ~A
      (parameterize ((%show-error-details
                      (assoc-ref opts 'show-error-details)))
 
-       (let* ((agent-communication-thunk
-               (let ((agent-communication-uri
-                      (assq-ref opts 'agent-communication)))
-                 (match (uri-scheme agent-communication-uri)
-                   ('http
-                    (let ((host (uri-host agent-communication-uri))
-                          (port (uri-port agent-communication-uri))
-                          (chunked-request-channel
-                           ;; There are fibers issues when trying to read the
-                           ;; chunked requests
-                           (make-worker-thread-channel (const '())
-                                                       #:parallelism 8)))
-                      (lambda ()
-                        (simple-format #t "listening on ~A:~A\n"
-                                       host port)
+       ;; Create some worker thread channels, which need to be created prior
+       ;; to run-fibers being called.
+       (let ((chunked-request-channel
+              ;; There are fibers issues when trying to read the chunked
+              ;; requests, so do this in dedicated threads.
+              (make-worker-thread-channel (const '())
+                                          #:parallelism 8))
+             (substitutes-channel
+              (make-worker-thread-channel (const '())
+                                          #:parallelism 2)))
+
+         (start-hook-processing-threads build-coordinator)
+         (trigger-build-allocation build-coordinator)
+
+         (let ((finished? (make-condition)))
+           (call-with-sigint
+            (lambda ()
+              (run-fibers
+               (lambda ()
+                 ;; Start the agent messaging server
+                 (let ((agent-communication-uri
+                        (assq-ref opts 'agent-communication)))
+                   (match (uri-scheme agent-communication-uri)
+                     ('http
+                      (let ((host (uri-host agent-communication-uri))
+                            (port (uri-port agent-communication-uri)))
                         (http-agent-messaging-start-server
                          port
                          host
                          (assq-ref opts 'secret-key-base)
                          build-coordinator
-                         chunked-request-channel)))))))
-              (client-communication-thunk
-               (let ((client-communication-uri
-                      (assq-ref opts 'client-communication))
-                     (substitutes-channel
-                      (make-worker-thread-channel (const '())
-                                                  #:parallelism 2)))
-                 (lambda ()
+                         chunked-request-channel)
+                        (simple-format #t "listening on ~A:~A\n"
+                                       host port)))))
+
+                 ;; Start the client messaging server
+                 (let ((client-communication-uri
+                        (assq-ref opts 'client-communication)))
                    (start-client-request-server
                     (assq-ref opts 'secret-key-base)
                     (uri-host client-communication-uri)
                     (uri-port client-communication-uri)
                     build-coordinator
-                    substitutes-channel)))))
-
-         (start-hook-processing-threads build-coordinator)
-         (trigger-build-allocation build-coordinator)
-
-         (let ((finished? (make-condition)))
-           (call-with-sigint
-            (lambda ()
-              (run-fibers
-               (lambda ()
-                 (agent-communication-thunk)
-                 (client-communication-thunk)
+                    substitutes-channel))
 
                  (wait finished?))))
-            finished?)))))))
+            finished?))))))))))