feat: support custom build dir names and paths

Signed-off-by: Jonah Snider <[email protected]>

Author: jonahsnider

readme.md

@@ -4,7 +4,7 @@
 [![Build Status](https://github.com/pizzafox/netlify-cache-nextjs/workflows/CI/badge.svg)](https://github.com/pizzafox/netlify-cache-nextjs/actions)
 [![XO code style](https://img.shields.io/badge/code_style-XO-5ed9c7.svg)](https://github.com/xojs/xo)
 
-Cache the `.next` folder in Netlify builds.
+Cache the Next.js build folder in Netlify builds.
 A [Netlify plugin](https://www.netlify.com/build/plugins-beta/) which is [published on npm](https://www.npmjs.com/package/netlify-plugin-cache-nextjs).
 
 ## Usage
@@ -20,6 +20,20 @@ To install, add the following lines to your `netlify.toml` file:
 package = "netlify-plugin-cache-nextjs"
 ```
 
+And if you want to configure the plugin:
+
+```toml
+[[plugins]]
+package = "netlify-plugin-cache-nextjs"
+
+	# These options will cache the build directory at `${NETLIFY_BASE}/frontend/.next-build`
+	[plugins.inputs]
+	# The path to the build directory
+	build_dir_path = "frontend"
+	# Custom build directory if you aren't using `.next` (https://nextjs.org/docs/api-reference/next.config.js/setting-a-custom-build-directory)
+	custom_build_dir_name = ".next-build"
+```
+
 Note: The `[[plugins]]` line is required for each plugin, even if you have other plugins in your `netlify.toml` file already.
 
 ## Contributing

src/index.ts

@@ -7,31 +7,53 @@ interface NetlifyUtils {
 	};
 }
 
+interface NetlifyInputs {
+	custom_build_dir_name?: string;
+	build_dir_path?: string;
+}
+
 interface NetlifyOpts {
 	utils: NetlifyUtils;
 	netlifyConfig: {build: {base: string}};
+	inputs: NetlifyInputs;
 }
 
-const buildCachePath = '.next';
-const manifestPath = joinPaths(buildCachePath, 'build-manifest.json');
+function generateAbsolutePaths(options: Pick<NetlifyOpts, 'inputs' | 'netlifyConfig'>) {
+	/** The name of the build folder. `.next`, unless specially configured. */
+	const buildDirName = options.inputs.custom_build_dir_name ?? '.next';
+	/** The directory the build folder is in. Defaults to current directory, although some larger repositories might keep this in a `frontend` folder. */
+	const buildDirPathFromProject = options.inputs.build_dir_path ?? '.';
+
+	/** The absolute path to the build folder for Next.js. */
+	const absoluteBuildDirPath = joinPaths(options.netlifyConfig.build.base, buildDirPathFromProject, buildDirName);
+	/** The absolute path to the build manifest Next.js uses. */
+	const manifestPath = joinPaths(absoluteBuildDirPath, 'build-manifest.json');
+
+	return {
+		absolute: {
+			buildDir: absoluteBuildDirPath,
+			manifest: manifestPath
+		},
+		buildDirName
+	};
+}
 
 module.exports = {
 	name: 'cache-nextjs',
 	// Restore file/directory cached in previous builds.
 	// Does not do anything if:
 	//  - the file/directory already exists locally
 	//  - the file/directory has not been cached yet
-	async onPreBuild({utils, netlifyConfig}: NetlifyOpts) {
-		const directory = joinPaths(netlifyConfig.build.base, buildCachePath);
-
-		const success = await utils.cache.restore(directory, {
-			digest: [joinPaths(netlifyConfig.build.base, manifestPath)]
+	async onPreBuild({utils, netlifyConfig, inputs}: NetlifyOpts) {
+		const paths = generateAbsolutePaths({netlifyConfig, inputs});
+		const success = await utils.cache.restore(paths.absolute.buildDir, {
+			digest: [paths.absolute.manifest]
 		});
 
 		if (success) {
-			console.log(`Restored the cached .next folder at the location \`${directory}\``);
+			console.log(`Restored the cached ${paths.buildDirName} folder at the location \`${paths.absolute.buildDir}\``);
 		} else {
-			console.log(`Unable to restore the cached .next folder at the location \`${directory}\``);
+			console.log(`Unable to restore the cached ${paths.buildDirName} folder at the location \`${paths.absolute.buildDir}\``);
 		}
 	},
 	// Cache file/directory for future builds.
@@ -40,17 +62,17 @@ module.exports = {
 	//  - the file/directory is already cached and its contents has not changed
 	//    If this is a directory, this includes children's contents
 	// Note that this will cache after the build, even if it fails, which fcould be unwanted behavior
-	async onPostBuild({utils, netlifyConfig}: NetlifyOpts) {
-		const directory = joinPaths(netlifyConfig.build.base, buildCachePath);
+	async onPostBuild({utils, netlifyConfig, inputs}: NetlifyOpts) {
+		const paths = generateAbsolutePaths({netlifyConfig, inputs});
 
-		const success = await utils.cache.save(directory, {
-			digest: [joinPaths(netlifyConfig.build.base, manifestPath)]
+		const success = await utils.cache.save(paths.absolute.buildDir, {
+			digest: [paths.absolute.manifest]
 		});
 
 		if (success) {
-			console.log(`Cached the .next folder at the location \`${directory}\``);
+			console.log(`Cached the ${paths.buildDirName} folder at the location \`${paths.absolute.buildDir}\``);
 		} else {
-			console.error(`An error occurred and the .next folder at the location \`${directory}\` could not be cached`);
+			console.error(`An error occurred and the ${paths.buildDirName} folder at the location \`${paths.absolute.buildDir}\` could not be cached`);
 		}
 	}
 };