PgMigrator
Runs database migrations for PostgreSQL projects that use Effect SQL.
This module reuses the shared SQL migrator and connects it to PostgreSQL. It
exposes the common migration helpers and adds run and layer functions
that apply pending migration files with the current SQL client. When schema
dumps are requested, it uses pg_dump and the usual process and filesystem
services.
Constructors
make
Creates a migrator that ensures the migrations table exists, runs pending migrations in a transaction, and optionally dumps the schema after successful migrations.
Signature
declare const make: <RD = never>({ dumpSchema }: { dumpSchema?: (path: string, migrationsTable: string) => Effect.Effect<void, MigrationError, RD>;}) => <R2 = never>({ loader, schemaDirectory, table }: MigratorOptions<R2>) => Effect.Effect<ReadonlyArray<readonly [id: number, name: string]>, MigrationError | SqlError, Client.SqlClient | RD | R2>Errors
MigrationError
Error raised while loading, validating, locking, or running SQL migrations.
Signature
declare class MigrationError extends MigrationError_base<{ readonly _tag: "MigrationError"; readonly cause?: unknown; readonly kind: "BadState" | "ImportError" | "Failed" | "Duplicates" | "Locked"; readonly message: string;}> { constructor(args: { readonly cause?: unknown; readonly kind: "BadState" | "ImportError" | "Failed" | "Duplicates" | "Locked"; readonly message: string; });}Layers
Creates a layer that runs PostgreSQL migrations during layer construction, including pg_dump-based schema dump support when requested.
Signature
declare function layer<R>(options: MigratorOptions<R>): Layer<never, SqlError | MigrationError, PgClient | SqlClient | ChildProcessSpawner | FileSystem | Path | R>Loaders
fromBabelGlob
Creates a migration loader from a Babel-style glob record, parsing keys such
as _<id>_<name>Js, _<id>_<name>Ts, _<id>_<name>Mjs, or
_<id>_<name>Mts and sorting migrations by id.
Signature
declare const fromBabelGlob: (migrations: Record<string, any>) => LoaderfromFileSystem
Creates a migration loader that reads a directory with FileSystem, imports
files named <id>_<name>.js, <id>_<name>.ts,
<id>_<name>.mjs, or <id>_<name>.mts, and sorts migrations by id.
Details
Requires a Path service appropriate for the migration directory's path
syntax. On Windows, prefer a platform-aware implementation such as
NodePath.layer; the core Path.layer uses POSIX semantics and does not
preserve Windows drive-letter paths.
Signature
declare const fromFileSystem: (directory: string) => Loader<FileSystem | Path>fromGlob
Creates a migration loader from a glob record of dynamic import functions,
parsing files named <id>_<name>.js, <id>_<name>.ts,
<id>_<name>.mjs, or <id>_<name>.mts and sorting migrations by id.
Signature
declare const fromGlob: (migrations: Record<string, () => Promise<any>>) => LoaderfromRecord
Creates a migration loader from a record of migration effects keyed by
<id>_<name>, sorted by migration id.
Signature
declare const fromRecord: (migrations: Record<string, Effect.Effect<void, unknown, Client.SqlClient>>) => LoaderModels
Loader type
Effect that resolves the available migrations for the migrator or fails with a
MigrationError.
Signature
type Loader<R = never> = Effect.Effect<ReadonlyArray<ResolvedMigration>, MigrationError, R>Migration interface
Metadata for a migration recorded in the migrations table, including its id, name, and creation timestamp.
Signature
interface Migration { readonly createdAt: Date; readonly id: number; readonly name: string;}ResolvedMigration type
Tuple produced by a migration loader, containing the migration id, migration name, and an effect that loads the migration implementation.
Signature
type ResolvedMigration = readonly [id: number, name: string, load: Effect.Effect<any, any, Client.SqlClient>]Options
MigratorOptions interface
Options for running SQL migrations, including the migration loader, optional schema dump directory, and migrations table name.
Signature
interface MigratorOptions<R = never> { readonly loader: Loader<R>; readonly schemaDirectory?: string; readonly table?: string;}Running
Runs PostgreSQL SQL migrations using the configured clients. Schema dumps use pg_dump and require child process, filesystem, and path services.
Signature
declare const run: <R2 = never>(options: Migrator.MigratorOptions<R2>) => Effect.Effect<ReadonlyArray<readonly [id: number, name: string]>, Migrator.MigrationError | SqlError, SqlClient | PgClient | ChildProcessSpawner.ChildProcessSpawner | FileSystem.FileSystem | Path.Path | R2>