[+] apply admin functions migrations for v5, fixes #1180 (#1181)

* Apply admin functions migrations for v5

* drop function `ensure_partition_metric_dbname_time` in v5 migration

for easier migration from v4.0.0 => v5.0.0

* Fix use `,` not `;`

* make linter happy

* fix tests

* make linter happy

* bump `sinkSchema` to the latest version

---------

Co-authored-by: Pavlo Golub <pavlo.golub@gmail.com>

Author: 0xgouda

cmd/pgwatch/version.go

@@ -8,7 +8,7 @@ var (
 	version      = "unknown"
 	date         = "unknown"
 	configSchema = "00824"
-	sinkSchema   = "01110"
+	sinkSchema   = "01180"
 )
 
 func printVersion() {

internal/sinks/postgres.go

@@ -603,6 +603,23 @@ var migrations func() migrator.Option = func() migrator.Option {
 			},
 		},
 
+		&migrator.Migration{
+			Name: "01180 Apply admin functions migrations for v5",
+			Func: func(ctx context.Context, tx pgx.Tx) error {
+				_, err := tx.Exec(ctx, `DROP FUNCTION IF EXISTS admin.ensure_partition_metric_dbname_time`)
+				if err != nil {
+					return err
+				}
+
+				_, err = tx.Exec(ctx, sqlMetricEnsurePartitionPostgres)
+				if err != nil {
+					return err
+				}
+				_, err = tx.Exec(ctx, sqlMetricAdminFunctions)
+				return err
+			},
+		},
+
 		// adding new migration here, update "admin"."migration" in "admin_schema.sql"!
 
 		// &migrator.Migration{

internal/sinks/postgres_schema_test.go

@@ -1,23 +1,62 @@
 package sinks
 
 import (
+	"context"
 	"testing"
 
 	migrator "github.com/cybertec-postgresql/pgx-migrator"
+	"github.com/jackc/pgx/v5"
 	"github.com/pashagolub/pgxmock/v4"
 	"github.com/stretchr/testify/assert"
 )
 
 func TestPostgresWriterMigrate(t *testing.T) {
+	oldInitMigrator := initMigrator
+	t.Cleanup(func() {
+		initMigrator = oldInitMigrator
+	})
+
 	a := assert.New(t)
 	conn, err := pgxmock.NewPool()
 	a.NoError(err)
 
-	// Expect migration table creation and migration execution
+	// Mock the migrator to use simple migrations for testing
+	initMigrator = func(_ *PostgresWriter) (*migrator.Migrator, error) {
+		return migrator.New(
+			migrator.TableName("admin.migration"),
+			migrator.Migrations(
+				&migrator.Migration{
+					Name: "Test migration 1",
+					Func: func(ctx context.Context, tx pgx.Tx) error {
+						_, err := tx.Query(ctx, "SELECT 1 AS col1")
+						return err
+					},
+				},
+				&migrator.Migration{
+					Name: "Test migration 2",
+					Func: func(ctx context.Context, tx pgx.Tx) error {
+						_, err := tx.Query(ctx, "SELECT 2 AS col2")
+						return err
+					},
+				},
+			),
+		)
+	}
+
 	conn.ExpectExec(`CREATE TABLE IF NOT EXISTS admin\.migration`).WillReturnResult(pgxmock.NewResult("CREATE", 1))
 	conn.ExpectQuery(`SELECT count`).WillReturnRows(pgxmock.NewRows([]string{"count"}).AddRow(0))
+
+	// Expect transaction for migration 1 execution
+	conn.ExpectBegin()
+	conn.ExpectQuery(`SELECT 1 AS col1`).WillReturnRows(pgxmock.NewRows([]string{"col1"}).AddRow(1))
+	conn.ExpectExec(`INSERT INTO`).WillReturnResult(pgxmock.NewResult("INSERT", 1))
+	conn.ExpectCommit()
+
+	// Expect transaction for migration 2 execution
 	conn.ExpectBegin()
+	conn.ExpectQuery(`SELECT 2 AS col2`).WillReturnRows(pgxmock.NewRows([]string{"col2"}).AddRow(2))
 	conn.ExpectExec(`INSERT INTO`).WillReturnResult(pgxmock.NewResult("INSERT", 1))
+	conn.ExpectCommit()
 
 	pgw := &PostgresWriter{ctx: ctx, sinkDb: conn}
 	err = pgw.Migrate()
@@ -52,7 +91,7 @@ func TestPostgresWriterNeedsMigrationNoMigrationNeeded(t *testing.T) {
 	conn.ExpectQuery(`SELECT to_regclass`).
 		WithArgs("admin.migration").
 		WillReturnRows(pgxmock.NewRows([]string{"to_regclass"}).AddRow(true))
-	conn.ExpectQuery(`SELECT count`).WillReturnRows(pgxmock.NewRows([]string{"count"}).AddRow(1))
+	conn.ExpectQuery(`SELECT count`).WillReturnRows(pgxmock.NewRows([]string{"count"}).AddRow(2))
 
 	pgw := &PostgresWriter{ctx: ctx, sinkDb: conn}
 	needs, err := pgw.NeedsMigration()

internal/sinks/sql/admin_schema.sql

@@ -94,4 +94,6 @@ CREATE TABLE admin.migration(
 INSERT INTO
     admin.migration (id, version)
 VALUES
-    (0,  '01110 Apply postgres sink schema migrations');
+    (0,  '01110 Apply postgres sink schema migrations'),
+    (1,  '01180 Apply admin functions migrations for v5');
+    -- apply new migration value to `sinkSchema` in `cmd/pgwatch/version.go` file as well