Add a function to select channel instances for a revision

guix-data-service/model/channel-instance.scm

@@ -23,7 +23,8 @@
   #:use-module (guix utils)
   #:use-module (guix-data-service model utils)
   #:use-module (guix-data-service model derivation)
-  #:export (insert-channel-instances))
+  #:export (insert-channel-instances
+            select-channel-instances-for-guix-revision))
 
 (define (insert-channel-instances conn
                                   guix-revision-id
@@ -50,3 +51,50 @@ VALUES "
             derivation-ids)
        ", "))))
   #t)
+
+(define (select-channel-instances-for-guix-revision conn
+                                                    commit-hash)
+  (define query
+    "
+SELECT channel_instances.system,
+       derivations.file_name,
+       JSON_AGG(
+         json_build_object(
+           'build_server_id', builds.build_server_id,
+           'status',  latest_build_status.status,
+           'timestamp',  latest_build_status.timestamp,
+           'build_for_equivalent_derivation',
+           builds.derivation_file_name != derivations.file_name
+         )
+         ORDER BY latest_build_status.timestamp
+       ) AS builds
+FROM channel_instances
+INNER JOIN derivations
+  ON channel_instances.derivation_id = derivations.id
+INNER JOIN derivations_by_output_details_set
+  ON derivations.id = derivations_by_output_details_set.derivation_id
+LEFT OUTER JOIN builds
+  ON derivations_by_output_details_set.derivation_output_details_set_id =
+     builds.derivation_output_details_set_id
+LEFT OUTER JOIN (
+  SELECT DISTINCT ON (build_id) *
+  FROM build_status
+  ORDER BY build_id, timestamp DESC
+) AS latest_build_status
+  ON builds.id = latest_build_status.build_id
+INNER JOIN guix_revisions
+  ON guix_revisions.id = channel_instances.guix_revision_id
+WHERE guix_revisions.commit = $1
+GROUP BY channel_instances.system, derivations.file_name
+ORDER BY channel_instances.system DESC")
+
+  (map
+   (match-lambda
+     ((system derivation_file_name builds-json)
+      (list system
+            derivation_file_name
+            (filter (lambda (build)
+                      (assoc-ref build "status"))
+                    (vector->list
+                     (json-string->scm builds-json))))))
+   (exec-query conn query (list commit-hash))))