Support storing when builds start

This isn't particularly accurate, what's actually being stored is the current
time when the record is inserted in to the coordinator database, but that
should happen just before the agent starts the build, so hopefully that's good
enough.

1 files changed, 53 insertions, 0 deletions

diff --git a/guix-build-coordinator/datastore/sqlite.scm b/guix-build-coordinator/datastore/sqlite.scm
index 88db088..db9f807 100644
--- a/guix-build-coordinator/datastore/sqlite.scm
+++ b/guix-build-coordinator/datastore/sqlite.scm
@@ -27,6 +27,8 @@
             datastore-new-agent
             datastore-list-agents
             datastore-find-agent
+            datastore-store-build-start
+            datastore-find-build-starts
             datastore-count-setup-failures
             datastore-list-setup-failures-for-build
             datastore-fetch-setup-failures
@@ -592,6 +594,57 @@ VALUES "
        (store-output-metadata db build-id output-metadata))))
   #t)
 
+(define-method (datastore-store-build-start
+                (datastore <sqlite-datastore>)
+                build-id
+                agent-id)
+
+  (call-with-worker-thread
+   (slot-ref datastore 'worker-writer-thread-channel)
+   (lambda (db)
+     (sqlite-exec
+      db
+      (string-append
+       "
+INSERT INTO build_starts (
+  build_id, agent_id, start_time
+) VALUES ('"
+       build-id "', '"
+       agent-id "', "
+       "datetime('now')"
+       ")")))))
+
+(define-method (datastore-find-build-starts
+                (datastore <sqlite-datastore>)
+                build-id)
+  (call-with-worker-thread
+   (slot-ref datastore 'worker-reader-thread-channel)
+   (lambda (db)
+     (let ((statement
+            (sqlite-prepare
+             db
+             "
+SELECT start_time, agent_id
+FROM build_starts
+WHERE build_id = :build_id
+ORDER BY start_time DESC")))
+
+       (sqlite-bind-arguments
+        statement
+        #:build_id build-id)
+
+       (let ((result
+              (sqlite-map
+               (match-lambda
+                 (#(start_time agent_id)
+                  `((start-time . ,(match (strptime "%F %T" start_time)
+                                             ((parts . _) parts)))
+                    (agent-id   . ,agent_id))))
+               statement)))
+         (sqlite-reset statement)
+
+         result)))))
+
 (define (insert-setup-failure-and-remove-allocation
          db
          build-id