fix(bootstrap): 迁库比对行数的 SQL 不再对常量排序报错，宿主机库能真正迁入 felis-postgres

# The units that write to the database from the host; the move stops them and starts

# again the ones that were running.

PG_MOVE_TIMERS=(felis-db-backup felis-offsite felis-update-check felis-watchdog)

# Each public table with its exact row count, one per line, in a collation-independent

# order, so the two servers' answers compare byte for byte.

PG_TABLE_COUNTS="SELECT c.relname || ' ' || (xpath('/row/n/text()', query_to_xml(format('SELECT count(*) AS n FROM public.%I', c.relname), false, true, '')))[1]::text FROM pg_class c JOIN pg_namespace s ON s.oid = c.relnamespace WHERE s.nspname = 'public' AND c.relkind IN ('r', 'p') ORDER BY 1 COLLATE \"C\""

# Each public table with its exact row count, one per line, in byte order of the table names

# whatever the servers' collations (relname is a name, which sorts in collation "C" since

# PostgreSQL 12), so the two servers' answers compare byte for byte. internal/pgint runs it

# on the oldest and newest server the installer meets; the shell tests stub psql.

PG_TABLE_COUNTS="SELECT c.relname || ' ' || (xpath('/row/n/text()', query_to_xml(format('SELECT count(*) AS n FROM public.%I', c.relname), false, true, '')))[1]::text FROM pg_class c JOIN pg_namespace s ON s.oid = c.relnamespace WHERE s.nspname = 'public' AND c.relkind IN ('r', 'p') ORDER BY c.relname"

PG_MOVE_STAGE=""

PG_MOVE_HBA=""

PG_MOVE_UNITS=()

//go:build pgint

package pgint

import (

	"context"

	"database/sql"

	"fmt"

	"os/exec"

	"slices"

	"sort"

	"strings"

	"testing"

)

// The row-count query deploy/bootstrap.sh runs on the host PostgreSQL and on felis-postgres

// when it moves the database into k3s, comparing the two answers byte for byte: every public

// table with its exact row count, one per line, in byte order of the table names. The shell

// tests stub psql, so this is the only place the SQL itself runs before a real host does.

func TestInstallerTableCounts(t *testing.T) {

	// bash reads the assignment the way the installer does, quoting and escapes included.

	out, err := exec.Command("bash", "-c", `eval "$(grep '^PG_TABLE_COUNTS=' "$1")" && printf %s "$PG_TABLE_COUNTS"`,

		"bash", "../../deploy/bootstrap.sh").Output()

	if err != nil || len(out) == 0 {

		t.Fatalf("reading PG_TABLE_COUNTS from deploy/bootstrap.sh: %v (%q)", err, out)

	}

	ctx := context.Background()

	// Tables the schema does not have yet but a migration may add: a name needing quotes,

	// which byte order puts before every lowercase one and a locale's order does not, and a

	// partitioned table.

	for _, stmt := range []string{

		`CREATE TABLE public."Pgint_Counts" (id int)`,

		`INSERT INTO public."Pgint_Counts" VALUES (1), (2), (3)`,

		`CREATE TABLE public.pgint_counts_parted (id int) PARTITION BY RANGE (id)`,

		`CREATE TABLE public.pgint_counts_parted_all PARTITION OF public.pgint_counts_parted FOR VALUES FROM (0) TO (100)`,

		`INSERT INTO public.pgint_counts_parted VALUES (1), (2)`,

	} {

		if _, err := db.ExecContext(ctx, stmt); err != nil {

			t.Fatalf("%s: %v", stmt, err)

		}

	}

	t.Cleanup(func() {

		_, _ = db.ExecContext(context.Background(), `DROP TABLE IF EXISTS public."Pgint_Counts", public.pgint_counts_parted`)

	})

	// One snapshot for the query and the counts it is checked against.

	tx, err := db.BeginTx(ctx, &sql.TxOptions{Isolation: sql.LevelRepeatableRead, ReadOnly: true})

	if err != nil {

		t.Fatal(err)

	}

	defer func() { _ = tx.Rollback() }()

	rows, err := tx.QueryContext(ctx, string(out))

	if err != nil {

		t.Fatalf("PG_TABLE_COUNTS: %v", err)

	}

	var got []string

	for rows.Next() {

		var line string

		if err := rows.Scan(&line); err != nil {

			t.Fatal(err)

		}

		got = append(got, line)

	}

	if err := rows.Err(); err != nil {

		t.Fatalf("PG_TABLE_COUNTS: %v", err)

	}

	names, err := publicTables(ctx, tx)

	if err != nil {

		t.Fatal(err)

	}

	sort.Strings(names) // byte order, what COLLATE "C" sorts by

	var want []string

	for _, name := range names {

		var n int64

		q := `SELECT count(*) FROM public."` + strings.ReplaceAll(name, `"`, `""`) + `"`

		if err := tx.QueryRowContext(ctx, q).Scan(&n); err != nil {

			t.Fatal(err)

		}

		want = append(want, fmt.Sprintf("%s %d", name, n))

	}

	if !slices.Contains(want, "Pgint_Counts 3") || !slices.Contains(want, "pgint_counts_parted 2") {

		t.Fatalf("the tables this test made are not what it counts: %q", want)

	}

	if !slices.Equal(got, want) {

		t.Fatalf("PG_TABLE_COUNTS returned\n%s\nwant\n%s", strings.Join(got, "\n"), strings.Join(want, "\n"))

	}

}

func publicTables(ctx context.Context, tx *sql.Tx) ([]string, error) {

	rows, err := tx.QueryContext(ctx, "SELECT tablename FROM pg_tables WHERE schemaname = 'public'")

	if err != nil {

		return nil, err

	}

	defer rows.Close()

	var names []string

	for rows.Next() {

		var name string

		if err := rows.Scan(&name); err != nil {

			return nil, err

		}

		names = append(names, name)

	}

	return names, rows.Err()

}