go-pgkit

README

go-pgkit

PostgreSQL helpers for pgx: error checks, timestamptz converters, pool with retry, and migration runners (goose and golang-migrate).

Install

go get github.com/takuya-go-kit/go-pgkit

import "github.com/takuya-go-kit/go-pgkit/pgutil"
import "github.com/takuya-go-kit/go-pgkit/postgres"
import "github.com/takuya-go-kit/go-pgkit/migrator/goose"
import "github.com/takuya-go-kit/go-pgkit/migrator/migrate"

Subpackages

pgutil

• IsNoRows(err) — true if err is or wraps pgx.ErrNoRows
• IsPgErrorCode(err, code) — true if err is a PgError with the given SQLSTATE code
• IsPgUniqueViolation(err) — true if PostgreSQL unique violation (23505)
• IsForeignKeyViolation(err) — true if PostgreSQL foreign key violation (23503)
• IsNotNullViolation(err) — true if PostgreSQL not null violation (23502)
• PgErrorCode(err) — SQLSTATE code or ""
• TimestamptzToTime(t) — *time.Time or nil if invalid
• TimestamptzToTimeZero(t) — time.Time or zero if invalid
• TimeToTimestamptz(t) — pgtype.Timestamptz (invalid if t is nil)
• PtrTimeToTime(t) — dereference or time.Time{}

postgres

• Config — URL, MaxConns, MinConns, RetryTimeout; optional MaxConnLifetime, MaxConnIdleTime, HealthCheckPeriod, ConnectTimeout (0 = defaults)
• New(ctx, cfg) — create pgxpool with exponential backoff retry until Ping succeeds

migrator

Two runners in subpackages; use the one that matches your migration layout.

• goose.Run(ctx, connStr, migrationsPath) — pressly/goose: SQL files with -- +goose Up / -- +goose Down
• migrate.Run(ctx, connURL, migrationsPath) — golang-migrate: NNNNNN_name.up.sql / NNNNNN_name.down.sql; treats ErrNoChange as success. Note: The underlying library's Up() does not accept context; a migration in progress cannot be cancelled. For long-running migrations, consider setting statement_timeout at the session or DB level.

Example

pool, err := postgres.New(ctx, &postgres.Config{
    URL:     os.Getenv("DATABASE_URL"),
    MaxConns: 20,
})
if err != nil {
    log.Fatal(err)
}
defer pool.Close()

if err := goose.Run(ctx, connStr, "./migrations"); err != nil {
    log.Fatal(err)
}

var t pgtype.Timestamptz
err := pool.QueryRow(ctx, "SELECT created_at FROM users WHERE id = $1", id).Scan(&t)
if pgutil.IsNoRows(err) {
    return ErrNotFound
}
createdAt := pgutil.TimestamptzToTime(t)