Avoid erroring when processing emails again

These changes allow processing emails again, and just creating job and branch
entries where data is missing.

guix-data-service/jobs/load-new-guix-revision.scm

@@ -630,12 +630,15 @@ WHERE job_id = $1"
     "
 INSERT INTO load_new_guix_revision_jobs (git_repository_id, commit, source)
 VALUES ($1, $2, $3)
+ON CONFLICT DO NOTHING
 RETURNING id;")
 
-  (first
-   (exec-query conn
-               query
-               (list git-repository-id commit source))))
+  (match (exec-query conn
+                     query
+                     (list git-repository-id commit source))
+    ((result)
+     result)
+    (() #f)))
 
 (define (select-job-for-commit conn commit)
   (let ((result

sqitch/deploy/remove_duplicate_load_new_guix_revision_jobs.sql

@@ -0,0 +1,25 @@
+-- Deploy guix-data-service:remove_duplicate_load_new_guix_revision_jobs to pg
+
+BEGIN;
+
+DELETE FROM load_new_guix_revision_job_events WHERE job_id NOT IN (
+  SELECT MIN(id) FROM load_new_guix_revision_jobs
+  GROUP BY commit, git_repository_id
+);
+
+DELETE FROM load_new_guix_revision_job_logs WHERE job_id NOT IN (
+  SELECT MIN(id) FROM load_new_guix_revision_jobs
+  GROUP BY commit, git_repository_id
+);
+
+DELETE FROM load_new_guix_revision_jobs WHERE id NOT IN (
+  SELECT MIN(id) FROM load_new_guix_revision_jobs
+  GROUP BY commit, git_repository_id
+);
+
+CREATE UNIQUE INDEX ON load_new_guix_revision_jobs (
+  commit,
+  git_repository_id
+);
+
+COMMIT;

sqitch/revert/remove_duplicate_load_new_guix_revision_jobs.sql

@@ -0,0 +1,7 @@
+-- Revert guix-data-service:remove_duplicate_load_new_guix_revision_jobs from pg
+
+BEGIN;
+
+-- XXX Add DDLs here.
+
+COMMIT;

sqitch/sqitch.plan

@@ -17,3 +17,4 @@ load_new_guix_revision_job_logs 2019-06-21T14:33:09Z chris <chris@phact> # Add l
 change_load_new_guix_revision_job_logs_contents_to_be_nullable 2019-07-07T20:10:54Z Christopher Baines <mail@cbaines.net> # Change the contents field in the load_new_guix_revision_job_logs table\nto be nullable.\n\nwith '#' will # be ignored, and an empty message aborts the add.  #\nChange to add: # #\nchange_load_new_guix_revision_job_logs_contents_to_be_nullable #\nsqitch/deploy/change_load_new_guix_revision_job_logs_contents_to_be_nullable.sql\nsqitch/revert/change_load_new_guix_revision_job_logs_contents_to_be_nullable.sql\nsqitch/verify/change_load_new_guix_revision_job_logs_contents_to_be_nullable.sql
 fix_duplicated_licenses 2019-07-30T05:48:17Z Christopher Baines <mail@cbaines.net> # Fix duplicated licenses, and add constraints
 change_git_branches_primary_key 2019-08-05T18:57:41Z Christopher Baines <mail@cbaines.net> # Change the git_branches primary key to include the git_repository_id,\nas this will allow having the same branch in different repositories.
+remove_duplicate_load_new_guix_revision_jobs 2019-08-05T19:06:36Z Christopher Baines <mail@cbaines.net> # Remove duplicate load_new_guix_revision_jobs

sqitch/verify/remove_duplicate_load_new_guix_revision_jobs.sql

@@ -0,0 +1,7 @@
+-- Verify guix-data-service:remove_duplicate_load_new_guix_revision_jobs on pg
+
+BEGIN;
+
+-- XXX Add verifications here.
+
+ROLLBACK;

tests/jobs-load-new-guix-revision.scm

@@ -82,7 +82,24 @@
          ((id)
           (process-load-new-guix-revision-job id))))))
 
-   (exec-query conn "TRUNCATE load_new_guix_revision_jobs CASCADE")))
+   (exec-query conn "TRUNCATE load_new_guix_revision_jobs CASCADE")
+
+   (test-assert "test duplicate job handling"
+     (with-postgresql-transaction
+      conn
+      (lambda (conn)
+        (enqueue-load-new-guix-revision-job
+         conn
+         (git-repository-url->git-repository-id conn "test-url")
+         "test-commit"
+         "test-source")
+        (enqueue-load-new-guix-revision-job
+         conn
+         (git-repository-url->git-repository-id conn "test-url")
+         "test-commit"
+         "test-source")
+        #t)
+      #:always-rollback? #t))))
 
 
 (test-end)

tests/model-git-branch.scm

@@ -22,6 +22,25 @@
                                    id
                                    (current-date)))
         #t)
+      #:always-rollback? #t))
+
+   (test-assert "insert-git-branch-entry works twice"
+     (with-postgresql-transaction
+      conn
+      (lambda (conn)
+        (let* ((url "test-url")
+               (id (git-repository-url->git-repository-id conn url)))
+          (insert-git-branch-entry conn
+                                   "master"
+                                   "test-commit"
+                                   id
+                                   (current-date))
+          (insert-git-branch-entry conn
+                                   "master"
+                                   "test-commit"
+                                   id
+                                   (current-date)))
+        #t)
       #:always-rollback? #t))))
 
 (test-end)