aj0strow/jackc-pgx-migrate

simple migrations for jackc/pgx database client

Simple Migrations for jackc/pgx

Quick and opinionated migration framework. It only supports "up" migrations, PostgreSQL database, golang app, jackc/pgx database client, int64 migration keys. It will create a new database table migrations with primary key mts which stands for migration unix timestamp.

Shell command to create a new migration key:

$ date +%s

Go import path:

github.com/aj0strow/jackc-pgx-migrate

Example

package main

import (
  "context"
  "github.com/aj0strow/jackc-pgx-migrate"
  "github.com/jackc/pgx/v4"
  "log"
  "os"
)

func migrate() {
  conn, err := pgx.Connect(context.Background(), os.Getenv("DATABASE_URL"))
  if err != nil {
    log.Fatal(err)
  }
  defer conn.Close()
  
  m := migrate.Funcs{}

  m[1575346891] = func(ctx context.Context, tx pgx.Tx) error {
    return migrate.Run(ctx, tx, []string{
      `CREATE TABLE users (
        id SERIAL PRIMARY KEY,
        email TEXT NOT NULL
      )`,
      `CREATE UNIQUE INDEX users_email_key ON users (email)`,
    })
  }

  // etc

  err = migrate.Migrate(ctx, conn, m)
  if err != nil {
    log.Fatal(err)
  }
}

Simple Benefits

Complex migration updating lots of data:

  m[1577567921] = func(ctx context.Context, tx pgx.Tx) error {
    // do whatever you want
    store := &Store{Tx: tx}
  }

Simple migration running commands:

  m[1577567921] = func(ctx context.Context, tx pgx.Tx) error {
    return migrate.Run(ctx, tx, []string{
      `CREATE TABLE ...`,
      `CREATE INDEX ...`,
    })
  }

Shorthand for simple migration running commands:

  m[1577569133] = migrate.Commands(
    `CREATE TABLE ...`,
    `CREATE INDEX ...`,
  )

Log commands during a more complex migration:

  logger := log.New(os.Stdout, "", 0)

  m[1577567921] = func(ctx context.Context, tx pgx.Tx) error {
    return migrate.Log(logger).Run(ctx, tx, []string{
      `CREATE TABLE ...`,
      `CREATE INDEX ...`,
    })
  }

Log commands while running them:

  logger := log.New(os.Stdout, "", 0)

  m[1577571429] = migrate.Log(logger).Commands(
    `CREATE TABLE ...`,
    `CREATE INDEX ...`,
  )

Adding migrations from different parts of the app:

package subapp

import (
  "github.com/aj0strow/jackc-pgx-migrate"
)

func MigrateFuncs() migrate.Funcs {
  m := migrate.Funcs{}

  // add migration functions

  return m
}

package main

import (
  "github.com/aj0strow/jackc-pgx-migrate"
  "subapp"
)

func migrate() {
  m := migrate.Funcs{}
  for k, v := range subapp.MigrateFuncs() {
    m[k] = v
  }
  // add migration funcions
}

Running Tests

Create a new database:

$ createdb jackc_pgx_migrate

Set the database connection string before running tests:

DATABASE_URL=postgres://localhost/jackc_pgx_migrate go test .

It sets the search_path to 'pg_temp' to avoid cleanup between test runs.