flat

interface FlatBarrelConfig {
    type: "flat";
    banner?: boolean | string;
    directories?: string | string[];
    files: string | string[];
    include?: string | RegExp | readonly (string | RegExp)[];
    exclude?: string | RegExp | readonly (string | RegExp)[];
    output?: string | ((directory: string) => string);
    extensions?: "auto" | false | Record<string, string>;
    resolveExports?: boolean;
    transformSources?: (sources: Source[]) => Source[] | Promise<Source[]>;
    transformBarrel?: (barrel: string) => string | Promise<string>;
}

This config creates classic barrel files, re-exporting all sources as-is.

Example

barrels.config.ts

import { defineConfig } from "@monstermann/barrels";

export default defineConfig([
    {
        type: "flat",
        files: "./src/utils/*.ts",
        output: "./src/utils/index.ts",
        removeExtensions: true,
    },
]);

src/utils/index.ts

// Generated by @monstermann/barrels
/* eslint-disable */
/* prettier-ignore */
// dprint-ignore-file
// biome-ignore lint: disable

export * from "./foo";
export * from "./bar";
export * from "./baz";

Options

banner

interface Config {
    banner?: boolean | string;
}

When enabled (as is by default), prepends a banner:

// Generated by @monstermann/barrels
/* eslint-disable */
/* prettier-ignore */
// dprint-ignore-file
// biome-ignore lint: disable

You can turn this off by setting it to false:

export default defineConfig([
    {
        banner: false,
    },
]);

Or define your own:

export default defineConfig([
    {
        banner: "// My custom banner",
    },
]);

directories

interface Config {
    directories?: string | string[];
}

Paths or globs to directories to create the barrel files in, by default set to process.cwd().

export default defineConfig([
    {
        // For each directory in "./src/utils/":
        directories: "./src/utils/*",
        // Find all immediate ".ts" files:
        files: "*.ts",
        // And create an "index.ts" in the respective directory:
        output: "index.ts",
    },
]);

files

interface Config {
    files: string | string[];
}

Paths or globs to include files from, relative to each directory.

include

interface Config {
    include?: string | RegExp | readonly (string | RegExp)[];
}

RegExps or globs to quickly filter files. The checks are made against resolved absolute paths.

exclude

interface Config {
    exclude?: string | RegExp | readonly (string | RegExp)[];
}

RegExps or globs to quickly exclude files. The checks are made against resolved absolute paths, for example to kick out all external dependencies:

source.ts

export * from "external-dependency";
export const foo = true;

barrels.config.ts

export default defineConfig([
    {
        type: "flat",
        files: "./source.ts",
        output: "./index.ts",
        // Extract all exports from "source.ts":
        resolveExports: true,
        // Kick out re-exported modules coming from node_modules:
        exclude: "**/node_modules/**",
    },
]);

index.ts

export { foo } from "./source.ts";

output

interface Config {
    output?: string | ((directory: string) => string);
}

The path to the file the barrel contents should be written to, relative to each directory, index.ts by default.

extensions

interface Config {
    extensions?: "auto" | false | Record<string, string>;
}

Controls how file extensions are handled when building import/export declarations, by default "auto".

export default defineConfig([
    {
        // Remove all extensions:
        extensions: false,
        // Remap specific extensions:
        extensions: {
            ts: "js",
        },
        // Decide based on `tsconfig` settings:
        // If `allowImportingTsExtensions` is turned on, leaves extensions as-is.
        // If `moduleResolution` is set to `bundler`, removes all extensions.
        // Otherwise eg. `ts` gets remapped to `js`.
        extensions: "auto",
    },
]);

removeExtensions

interface Config {
    removeExtensions?: boolean;
}

This allows you to remove all extensions, useful when tsconfig.compilerOptions.moduleResolution is set to bundler.

resolveExports

interface Config {
    resolveExports?: boolean;
}

Enabled by default when using { type: "namespace" } or { type: "record" }.

When enabled, will recursively extract individual export declarations from encountered files. This is necessary for some barrel types, but you can also use this to control what exactly is being exported instead of re-exporting all encountered files as export * from "file.ts".

source.ts

export const foo = true;

Before:

barrels.config.ts

export default defineConfig([
    {
        type: "flat",
        files: "./source.ts",
        output: "./index.ts",
    },
]);

index.ts

export * from "./source.ts";

After:

barrels.config.ts

export default defineConfig([
    {
        type: "flat",
        files: "./source.ts",
        output: "./index.ts",
        resolveExports: true,
    },
]);

index.ts

export { foo } from "./source.ts";

transformSources

interface Config {
    transformSources?: (sources: Source[]) => Source[] | Promise<Source[]>;
}

This allows you to modify the encountered files or exports before constructing barrel files.

See API/Guide for an overview!

transformBarrel

interface Config {
    transformBarrel?: (barrel: string) => string | Promise<string>;
}

This allows you to modify the created barrel contents before writing to disk.