Leonardo Devai
2665ea70b4
21 bite-sized beginner tutorials (Web Basics, APIs & Data), the 8-backend blog engine series, 4 blog frontends, 2 React starters, 3 NixOS desktops and 4 Rust API/pipeline boilerplates. Every folder is a complete, self-contained project with its own README. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01VGNxPf9PrSG2kzrxSvn45Y
44 lines
1,021 B
Go
44 lines
1,021 B
Go
package main
|
|
|
|
import (
|
|
"context"
|
|
_ "embed"
|
|
"errors"
|
|
"fmt"
|
|
"time"
|
|
|
|
"github.com/jackc/pgx/v5/pgconn"
|
|
"github.com/jackc/pgx/v5/pgxpool"
|
|
)
|
|
|
|
//go:embed schema.sql
|
|
var schemaSQL string
|
|
|
|
// openDB connects, waits briefly for Postgres to accept connections (useful
|
|
// under docker compose), and applies schema.sql — its statements are all
|
|
// idempotent, so this is safe on every start.
|
|
func openDB(ctx context.Context, url string) (*pgxpool.Pool, error) {
|
|
pool, err := pgxpool.New(ctx, url)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
for i := 0; ; i++ {
|
|
if err = pool.Ping(ctx); err == nil {
|
|
break
|
|
}
|
|
if i == 9 {
|
|
return nil, fmt.Errorf("ping: %w", err)
|
|
}
|
|
time.Sleep(time.Second)
|
|
}
|
|
if _, err := pool.Exec(ctx, schemaSQL); err != nil {
|
|
return nil, fmt.Errorf("apply schema: %w", err)
|
|
}
|
|
return pool, nil
|
|
}
|
|
|
|
// isDuplicate reports whether err is a Postgres unique-constraint violation.
|
|
func isDuplicate(err error) bool {
|
|
var pgErr *pgconn.PgError
|
|
return errors.As(err, &pgErr) && pgErr.Code == "23505"
|
|
}
|