Remove support for virtual storage scoped primaries in read-only metrics

This commit removes the support for virtual storage scoped primaries in the
read-only repository count metric to make future changes easier. Virtual
storage scoped primaries were deprecated in 13.12 and removed in 14.0.

Changelog: removed

3 files changed, 13 insertions, 85 deletions

diff --git a/cmd/praefect/main.go b/cmd/praefect/main.go
index 2418b8a90..a906ee21c 100644
--- a/cmd/praefect/main.go
+++ b/cmd/praefect/main.go
@@ -401,12 +401,7 @@ func run(cfgs []starter.Config, conf config.Config) error {
 	metricsCollectors = append(metricsCollectors, transactionManager, coordinator, repl)
 	if db != nil {
 		prometheus.MustRegister(
-			datastore.NewRepositoryStoreCollector(
-				logger,
-				conf.VirtualStorageNames(),
-				db,
-				conf.Failover.ElectionStrategy == config.ElectionStrategyPerRepository,
-			),
+			datastore.NewRepositoryStoreCollector(logger, conf.VirtualStorageNames(), db),
 		)
 	}
 	prometheus.MustRegister(metricsCollectors...)
diff --git a/internal/praefect/datastore/collector.go b/internal/praefect/datastore/collector.go
index 098c46dfb..3fdedc738 100644
--- a/internal/praefect/datastore/collector.go
+++ b/internal/praefect/datastore/collector.go
@@ -19,19 +19,17 @@ var descReadOnlyRepositories = prometheus.NewDesc(
 
 // RepositoryStoreCollector collects metrics from the RepositoryStore.
 type RepositoryStoreCollector struct {
-	log              logrus.FieldLogger
-	db               glsql.Querier
-	virtualStorages  []string
-	repositoryScoped bool
+	log             logrus.FieldLogger
+	db              glsql.Querier
+	virtualStorages []string
 }
 
 // NewRepositoryStoreCollector returns a new collector.
-func NewRepositoryStoreCollector(log logrus.FieldLogger, virtualStorages []string, db glsql.Querier, repositoryScoped bool) *RepositoryStoreCollector {
+func NewRepositoryStoreCollector(log logrus.FieldLogger, virtualStorages []string, db glsql.Querier) *RepositoryStoreCollector {
 	return &RepositoryStoreCollector{
-		log:              log.WithField("component", "RepositoryStoreCollector"),
-		db:               db,
-		virtualStorages:  virtualStorages,
-		repositoryScoped: repositoryScoped,
+		log:             log.WithField("component", "RepositoryStoreCollector"),
+		db:              db,
+		virtualStorages: virtualStorages,
 	}
 }
 
@@ -54,38 +52,8 @@ func (c *RepositoryStoreCollector) Collect(ch chan<- prometheus.Metric) {
 // queryMetrics queries the number of read-only repositories from the database.
 // A repository is in read-only mode when its primary storage is not on the latest
 // generation.
-//
-// There are two variants on the query:
-//
-// 1. virtualStorageScopedQuery considers virtual storage scoped primaries. Virtual storage's
-//    primary is stored in the `shard_primaries` table in the `node_name` column.
-// 2. repositoryScopedQuery considers repository specific primaries. Repository scoped
-//    primaries are stored in the `primary` column in the `repositories` table.
-//
-// Both queries cross-reference the `repositories` and `storage_repositories` tables
-// to see if the primary storage of the repository is on the latest generation. If not,
-// it's added to the returned count.
-//
-// The query operating on virtual storage scoped primaries will be dropped once the migration
-// to repository scoped primaries is finished.
 func (c *RepositoryStoreCollector) queryMetrics(ctx context.Context) (map[string]int, error) {
-	const virtualStorageScopedQuery = `
-SELECT repositories.virtual_storage, COUNT(*)
-FROM repositories
-LEFT JOIN shard_primaries ON
-	shard_primaries.shard_name = repositories.virtual_storage AND
-	shard_primaries.demoted = false
-LEFT JOIN storage_repositories ON
-	repositories.virtual_storage = storage_repositories.virtual_storage AND
-	repositories.relative_path = storage_repositories.relative_path AND
-	shard_primaries.node_name = storage_repositories.storage
-WHERE
-	COALESCE(storage_repositories.generation, -1) < repositories.generation AND
-	repositories.virtual_storage = ANY($1)
-GROUP BY repositories.virtual_storage;
-	`
-
-	const repositoryScopedQuery = `
+	const query = `
 SELECT repositories.virtual_storage, COUNT(*)
 FROM repositories
 LEFT JOIN storage_repositories ON
@@ -98,11 +66,6 @@ WHERE
 GROUP BY repositories.virtual_storage
 `
 
-	query := virtualStorageScopedQuery
-	if c.repositoryScoped {
-		query = repositoryScopedQuery
-	}
-
 	rows, err := c.db.QueryContext(ctx, query, pq.StringArray(c.virtualStorages))
 	if err != nil {
 		return nil, fmt.Errorf("query: %w", err)
diff --git a/internal/praefect/datastore/collector_test.go b/internal/praefect/datastore/collector_test.go
index 65248605e..edea5f409 100644
--- a/internal/praefect/datastore/collector_test.go
+++ b/internal/praefect/datastore/collector_test.go
@@ -3,7 +3,6 @@
 package datastore
 
 import (
-	"fmt"
 	"strings"
 	"testing"
 
@@ -57,17 +56,6 @@ func TestRepositoryStoreCollector(t *testing.T) {
 		},
 	}
 	for virtualStorage, relativePaths := range state {
-		demoted := false
-		if virtualStorage == "no-primary" {
-			demoted = true
-		}
-		_, err := db.ExecContext(ctx, `
-			INSERT INTO shard_primaries (shard_name, node_name, elected_by_praefect, elected_at, demoted)
-			VALUES ($1, 'vs-primary', 'not-needed', now(), $2)
-			`, virtualStorage, demoted,
-		)
-		require.NoError(t, err)
-
 		for relativePath, storages := range relativePaths {
 			if virtualStorage != "no-primary" {
 				_, err := db.ExecContext(ctx, `
@@ -93,31 +81,13 @@ func TestRepositoryStoreCollector(t *testing.T) {
 		virtualStorages = append(virtualStorages, vs)
 	}
 
-	for _, tc := range []struct {
-		desc              string
-		repositoryScoped  bool
-		someReadOnlyCount int
-	}{
-		{
-			desc:              "repository scoped",
-			someReadOnlyCount: 1,
-			repositoryScoped:  true,
-		},
-		{
-			desc:              "virtual storage scoped",
-			someReadOnlyCount: 2,
-		},
-	} {
-		t.Run(tc.desc, func(t *testing.T) {
-			c := NewRepositoryStoreCollector(logrus.New(), virtualStorages, db, tc.repositoryScoped)
-			require.NoError(t, testutil.CollectAndCompare(c, strings.NewReader(fmt.Sprintf(`
+	c := NewRepositoryStoreCollector(logrus.New(), virtualStorages, db)
+	require.NoError(t, testutil.CollectAndCompare(c, strings.NewReader(`
 # HELP gitaly_praefect_read_only_repositories Number of repositories in read-only mode within a virtual storage.
 # TYPE gitaly_praefect_read_only_repositories gauge
 gitaly_praefect_read_only_repositories{virtual_storage="all-writable"} 0
 gitaly_praefect_read_only_repositories{virtual_storage="no-records"} 0
 gitaly_praefect_read_only_repositories{virtual_storage="no-primary"} 1
-gitaly_praefect_read_only_repositories{virtual_storage="some-read-only"} %d
-`, tc.someReadOnlyCount))))
-		})
-	}
+gitaly_praefect_read_only_repositories{virtual_storage="some-read-only"} 1
+`)))
 }