add assetDir option

README.md

@@ -26,6 +26,13 @@ nunjucks: {
 
 ## Options
 
+### `assetDir`
+
+- Type: `string`
+- Default: `"public/assets"`
+
+Source directory to read assets from.
+
 ## Filters
 
 ### `assetUrl` filter

nunjucks.js

@@ -2,7 +2,9 @@ const crypto = require('crypto');
 const execSync = require('child_process').execSync;
 const fs = require('fs');
 
-const defaults = {};
+const defaults = {
+	assetDir: 'public/assets',
+};
 
 function wrapper(opt){
 	const options = Object.assign({}, defaults, opt);
@@ -26,20 +28,20 @@ function wrapper(opt){
 	}
 
 	function assetHash(asset){
-		const filename = `public/assets/${asset}`;
-		if (fs.existsSync(filename)){
+		const filename = getAsset(asset);
+		if (filename){
 			const data = fs.readFileSync(filename);
 			const hash = crypto.createHash('md5').update(data).digest('hex');
 			return `assets/${asset}?${hash}`;
 		} else {
-			console.log(`${filename} does not exist when trying to calculate asset hash.`);
+			console.log(`${options.assetDir}/${asset} does not exist when trying to calculate asset hash.`);
 			return `assets/${asset}`;
 		}
 	}
 
 	function sri(asset, algorithm){
-		const filename = `public/assets/${asset}`;
-		if (fs.existsSync(filename)){
+		const filename = getAsset(asset);
+		if (filename){
 			if (process.env.NODE_ENV === 'production'){ /* set in .gitlab-ci.yml */
 				const data = fs.readFileSync(filename);
 				const hash = crypto.createHash(algorithm).update(data).digest('base64');
@@ -48,10 +50,15 @@ function wrapper(opt){
 				return ''; /* SRI skipped for local builds */
 			}
 		} else {
-			console.log(`${filename} does not exist when trying to calculate SRI.`);
+			console.log(`${options.assetDir}/${asset} does not exist when trying to calculate SRI.`);
 			return '';
 		}
 	}
+
+	function getAsset(asset){
+		const filename = `${options.assetDir}/${asset}`;
+		return fs.existsSync(filename) ? filename : null;
+	}
 }
 
 module.exports = wrapper;