Fix #10 and #11: provide ESM/CJS modules for Node/browsers

Test various bundling configurations with
Webpack, Rollup and esbuild and test the
resulting bundles.

Author: undecaf

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,30 @@
+---
+name: Bug report
+about: Create a report to help me improve barcode-detector-polyfill
+title: "[BUG]"
+labels: bug
+assignees: ''
+
+---
+
+**Describe the bug**
+
+A clear and concise description of what the bug is.
+
+**To Reproduce**
+
+A minimal working example that reproduces the behavior would be much appreciated.
+
+Or else the environment in which the behavior occurs needs to be specified:
+ - Which target environment (Node/browser/other)?
+ - Which type of modules (ESM/CommonJS/other)?
+ - Which framework(s)?
+ - Which devtools, including their configuration files?
+ - `package.json` content
+ - Any other context about the problem
+
+**Expected behavior**  
+A clear and concise description of what you expected to happen.
+
+**Screenshots**  
+If applicable, add screenshots to help explain your problem.

.testcaferc.json

@@ -0,0 +1,5 @@
+{
+  "src": "tests/bundling-browser.test.js",
+  "browsers": [ "chromium:headless" ],
+  "hostname": "localhost"
+}

Makefile

@@ -4,12 +4,13 @@ ZBAR_SRC = zbar-$(ZBAR_VERSION)
 SRC = src
 BUILD = build
 DIST = dist
-TEST = test
-TEST_TS = $(wildcard ./$(TEST)/*.ts)
-TEST_JS = $(patsubst ./$(TEST)/%.ts,./$(BUILD)/%.js,$(TEST_TS))
-TEST_COVERAGE = ./coverage
+INLINED = $(DIST)/inlined
+TESTS = tests
+TESTS_SRC = $(wildcard ./$(TESTS)/[0123456789]*.test.ts)
+TESTS_BUILT = $(patsubst ./$(TESTS)/%.ts,./$(BUILD)/%.js,$(TESTS_SRC))
+TESTS_COVERAGE = ./coverage
 
-EM_VERSION = 3.1.30
+EM_VERSION = 3.1.44
 EM_OPTS = --rm -w /$(SRC) -v $$PWD:/$(SRC) emscripten/emsdk:$(EM_VERSION)
 EM_DOCKER = docker run -u $(shell id -u):$(shell id -g) $(EM_OPTS)
 EM_PODMAN = podman run $(EM_OPTS)
@@ -29,7 +30,10 @@ EMCC_FLAGS = -Oz -Wall -Werror -s ALLOW_MEMORY_GROWTH=1 \
 	-s EXPORTED_FUNCTIONS="['_malloc','_free']" \
 	-s MODULARIZE=1 -s EXPORT_NAME=zbarWasm
 
-BUNDLES = $(DIST)/main.js $(DIST)/main.cjs $(DIST)/index.js
+LOADERS = $(BUILD)/zbar.js $(BUILD)/zbar.mjs $(BUILD)/zbar-inlined.js $(BUILD)/zbar-inlined.mjs
+
+BUNDLES = $(DIST)/main.mjs $(DIST)/main.cjs $(DIST)/index.js $(DIST)/index.mjs \
+	$(INLINED)/main.mjs $(INLINED)/main.cjs $(INLINED)/index.js $(INLINED)/index.mjs
 
 TSC = npx tsc
 TSC_FLAGS = -p ./tsconfig.test.json
@@ -41,35 +45,39 @@ ROLLUP_FLAGS = -c
 
 all: dist test
 
-test: dist $(TEST_JS)
-	jest --config ./jest.config.cjs --coverage
+test: dist $(TESTS_BUILT)
+	node --experimental-vm-modules node_modules/jest/bin/jest.js --config ./jest.config.cjs --runInBand --coverage
 
 dist: $(BUNDLES) $(DIST)/zbar.wasm
 
 clean-build:
-	-rm -rf $(DIST) $(BUILD)
+	-rm -rf $(DIST) $(BUILD) undecaf-zbar-wasm-*.tgz $(TESTS)/node_modules $(TESTS)/build $(TESTS)/package-lock.json
 
 clean: clean-build
 	-rm $(ZBAR_SRC).tar.gz
-	-rm -rf $(ZBAR_SRC) $(TEST_COVERAGE)
+	-rm -rf $(ZBAR_SRC) $(TESTS_COVERAGE)
 
-$(TEST_JS): $(TEST_TS) $(BUNDLES) tsconfig.json tsconfig.test.json
+$(TESTS_BUILT): $(TESTS)/* $(BUNDLES) tsconfig.test.json jest.config.cjs .testcaferc.json
 	$(TSC) $(TSC_FLAGS)
 
-$(BUNDLES): $(BUILD)/zbar.js $(BUILD)/zbar.mjs $(SRC)/*.ts tsconfig.json rollup.config.js package.json
+$(BUNDLES): $(LOADERS) $(DIST)/zbar.wasm $(SRC)/*.ts tsconfig.json rollup.config.js package.json
+	mkdir -p $(DIST)/
 	$(ROLLUP) $(ROLLUP_FLAGS)
+	npm pack
 
 $(DIST)/zbar.wasm: $(BUILD)/zbar.wasm
 	mkdir -p $(DIST)/
 	cp $(BUILD)/zbar.wasm $(DIST)/
 
-$(BUILD)/zbar.wasm $(BUILD)/zbar.js $(BUILD)/zbar.mjs: $(ZBAR_DEPS) $(SRC)/module.c $(BUILD)/symbol.test.o
+$(BUILD)/zbar.wasm $(LOADERS): $(ZBAR_DEPS) $(SRC)/module.c $(BUILD)/symbol.test.o
 	$(EMCC) $(EMCC_FLAGS) -o $(BUILD)/zbar.js $(SRC)/module.c $(ZBAR_INC) $(ZBAR_OBJS)
-	$(EMCC) $(EMCC_FLAGS) -o $(BUILD)/zbar.mjs $(SRC)/module.c $(ZBAR_INC) $(ZBAR_OBJS)
+	$(EMCC) $(EMCC_FLAGS) -o $(BUILD)/zbar.mjs -sEXPORT_ES6 $(SRC)/module.c $(ZBAR_INC) $(ZBAR_OBJS)
+	$(EMCC) $(EMCC_FLAGS) -o $(BUILD)/zbar-inlined.js -sSINGLE_FILE $(SRC)/module.c $(ZBAR_INC) $(ZBAR_OBJS)
+	$(EMCC) $(EMCC_FLAGS) -o $(BUILD)/zbar-inlined.mjs -sEXPORT_ES6 -sSINGLE_FILE $(SRC)/module.c $(ZBAR_INC) $(ZBAR_OBJS)
 
-$(BUILD)/symbol.test.o: $(ZBAR_DEPS) $(TEST)/symbol.test.c
+$(BUILD)/symbol.test.o: $(ZBAR_DEPS) $(TESTS)/symbol.test.c
 	mkdir -p $(BUILD)/
-	$(EMCC) -Wall -Werror -g2 -c $(TEST)/symbol.test.c -o $@ $(ZBAR_INC)
+	$(EMCC) -Wall -Werror -g2 -c $(TESTS)/symbol.test.c -o $@ $(ZBAR_INC)
 
 $(ZBAR_DEPS): $(ZBAR_SRC)/Makefile
 	cd $(ZBAR_SRC) && $(EMMAKE) make CFLAGS=-Os CXXFLAGS=-Os \

README.md

@@ -1,6 +1,5 @@
 # A WebAssembly build of the ZBar Bar Code Reader
 
-![Install size](https://badgen.net/packagephobia/install/@undecaf/zbar-wasm?color=42cc24)
 ![Open issues](https://badgen.net/github/open-issues/undecaf/zbar-wasm)
 ![Vulnerabilities](https://snyk.io/test/npm/@undecaf/zbar-wasm/badge.svg)
 ![Total downloads](https://badgen.net/npm/dt/@undecaf/zbar-wasm)
@@ -15,6 +14,7 @@ of the [ZBar Bar Code Reader](https://github.com/mchehab/zbar) written in C/C++.
 
 + Provided as minified ES module, CommonJS module and plain script
 + Runs in modern browsers, in Node.js and also in workers
++ Deployment size approx. 330 kByte
 + Supports Code-39, Code-93, Code-128, Codabar, Databar/Expanded,
   EAN/GTIN-5/8/13, ISBN-10/13, ISBN-13+2, ISBN-13+5, ITF (Interleaved 2 of 5), QR Code, UPC-A/E.
 + Detects multiple barcodes per frame, also with different types
@@ -23,6 +23,8 @@ of the [ZBar Bar Code Reader](https://github.com/mchehab/zbar) written in C/C++.
   RGB/grayscale [`ArrayBuffer`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer) objects
 + Outperforms pure JavaScript barcode scanners
 
+:warning: v0.10.0 contains breaking changes regarding bundling, please refer to section [Bundling/deploying zbar-wasm](#bundling-deploying-zbar-wasm).
+
 
 ## Examples based on zbar-wasm
 
@@ -48,11 +50,11 @@ An example that scans a static image file:
 <!DOCTYPE html>
 <html>
 <body>
-  <img id="img" crossorigin="anonymous" src="https://raw.githubusercontent.com/undecaf/zbar-wasm/master/test/img/qr_code.png">
+  <img id="img" crossorigin="anonymous" src="https://raw.githubusercontent.com/undecaf/zbar-wasm/master/tests/img/qr_code.png">
   <pre id="result"></pre>
 
   <script type="module">
-    import * as zbarWasm from 'https://cdn.jsdelivr.net/npm/@undecaf/zbar-wasm@0.9.16/dist/main.js'
+    import * as zbarWasm from 'https://cdn.jsdelivr.net/npm/@undecaf/zbar-wasm@0.10.0/dist/main.js'
 
     (async () => {
       const
@@ -86,28 +88,28 @@ Almost identical to the snippet above, just replace the lines
 ```html
     ⁝
   <script type="module">
-    import * as zbarWasm from 'https://cdn.jsdelivr.net/npm/@undecaf/zbar-wasm@0.9.16/dist/main.js'
+    import * as zbarWasm from 'https://cdn.jsdelivr.net/npm/@undecaf/zbar-wasm@0.10.0/dist/main.js'
     ⁝
 ```
 
 with
 
 ```html
     ⁝
-  <script src="https://cdn.jsdelivr.net/npm/@undecaf/zbar-wasm@0.9.16/dist/index.js"></script>
+  <script src="https://cdn.jsdelivr.net/npm/@undecaf/zbar-wasm@0.10.0/dist/index.js"></script>
   <script>
     ⁝
 ```
 
 
-### Including zbar-wasm as ESM or as CommonJS module
+### Using zbar-wasm as an ESM or CommonJS module in Node.js
 
 Installing:
 
 ```shell script
-$ npm install @undecaf/zbar-wasm@0.9.16
+$ npm install @undecaf/zbar-wasm@0.10.0
     or
-$ yarn add @undecaf/zbar-wasm@0.9.16
+$ yarn add @undecaf/zbar-wasm@0.10.0
 ```
 
 Using:
@@ -117,42 +119,100 @@ Using:
 
 Please refer to the [API documentation](#api-documentation) for what can be imported/required.
 
-A simple Node.js example that scans a static image file:
+A simple ES module that scans a static image file:
 
 ```javascript
-const { createCanvas, loadImage } = require('canvas');
-const { scanImageData } = require('@undecaf/zbar-wasm');
+import { createCanvas, loadImage }  from 'canvas';
+import { scanImageData } from '@undecaf/zbar-wasm';
 
 (async (url) => {
   const
-    img = await loadImage(url),
-    canvas = createCanvas(img.width, img.height),
-    ctx = canvas.getContext('2d');
+          img = await loadImage(url),
+          canvas = createCanvas(img.width, img.height),
+          ctx = canvas.getContext('2d');
 
-  ctx.drawImage(img, 0, 0);
+  ctx.drawImage(img, 0, 0)
 
   const
-    imageData = ctx.getImageData(0, 0, img.width, img.height),
-    symbols = await scanImageData(imageData);
+          imageData = ctx.getImageData(0, 0, img.width, img.height),
+          // @ts-ignore
+          symbols = await scanImageData(imageData);
 
-  console.log(symbols[0].typeName, symbols[0].decode());
-}) ('https://raw.githubusercontent.com/undecaf/zbar-wasm/master/test/img/qr_code.png');
+  console.log(ssymbols[0]?.typeName, ymbols[0]?.decode())
+})('https://raw.githubusercontent.com/undecaf/zbar-wasm/master/tests/img/qr_code.png')
 ```
 
-### Bundling/deploying zbar-wasm
+For a CommonJS module, just replace the first lines with
 
-zbar-wasm loads the WebAssembly file `zbar.wasm` at runtime. `zbar.wasm` must be located in the same directory
-as the zbar-wasm `<script>` or module, be it on a file system or at a remote endpoint.
+```javascript
+const { createCanvas, loadImage } = require('canvas');
+const { scanImageData } = require('@undecaf/zbar-wasm');
+```
 
-This must be observed when bundling zbar-wasm or deploying it to a server:
 
-+ `@undecaf/zbar-wasm/dist/zbar.wasm` must be copied as-is (e.g. using [`copy-webpack-plugin`](https://www.npmjs.com/package/copy-webpack-plugin),
-  [`rollup-plugin-copy`](https://www.npmjs.com/package/rollup-plugin-copy), [`esbuild-plugin-copy`](https://www.npmjs.com/package/esbuild-plugin-copy)
-  or similar).
-+ `zbar.wasm` must be copied to the directory where the zbar-wasm module/the bundle containing that module is located.
-+ It should be served as `application/wasm` so that it can be compiled in parallel with being received 
-  by the browser.
+### Bundling/deploying zbar-wasm
 
+zbar-wasm delegates barcode scanning to the WebAssembly code in file `zbar.wasm`.
+This file is part of the package and can be provided at runtime in different ways:
+
++ It can be loaded from a CDN by browsers.
++ It can be bundled as an asset. That asset should be served to browsers as `application/wasm`
++ so that it can be compiled in parallel with being received.
++ zbar-wasm also provides modules that contain `zbar.wasm` as inline data. 
+
+The [package entry points](https://nodejs.org/docs/latest-v16.x/api/packages.html#package-entry-points)
+of zbar-wasm have been chosen so that bundlers will select the 
+appropriate module by default in most cases. `zbar.wasm` as inline data requires an
+[export condition](https://nodejs.org/docs/latest-v16.x/api/packages.html#conditional-exports)
+in the bundler configuration.
+
+The build process of zbar-wasm tests bundling with
+[Webpack](https://webpack.js.org/), [Rollup](https://rollupjs.org/) and 
+[esbuild](https://esbuild.github.io/) and also tests the resulting bundles.
+The bundler configuration files
+[`tests/{webpack,rollup,esbuild}.config.js`](https://github.com/undecaf/zbar-wasm/tree/master/tests)
+may be used as a reference of how to achieve a particular bundling result. They cover the following 
+combinations of platform, module type and `zbar.wasm` provisioning:
+
+<table>
+<thead>
+<tr>
+<th style='text-align: left;'>Platform &rarr;</th>
+<th colspan='2'>Node.js</th>
+<th colspan='2'>Browser</th>
+</tr>
+<tr>
+<th style='text-align: left;'><code>zbar.wasm</code>&darr;</th>
+<th>ESM</th>
+<th>CommonJS</th>
+<th>ESM</th>
+<th>Script</th>
+</tr>
+</thead>
+<tbody>
+<tr>
+<th style='text-align: left;'>from CDN</th>
+<td></td>
+<td></td>
+<td>:white_check_mark:</td>
+<td>:white_check_mark:</td>
+</tr>
+<tr>
+<th style='text-align: left;'>bundled</th>
+<td>:white_check_mark:</td>
+<td>:white_check_mark:</td>
+<td>:white_check_mark:</td>
+<td></td>
+</tr>
+<tr>
+<th style='text-align: left;'>inlined</th>
+<td>:white_check_mark:</td>
+<td>:white_check_mark:</td>
+<td>:white_check_mark:</td>
+<td>:white_check_mark:</td>
+</tr>
+</tbody>
+</table>
 
 ## API documentation
 
@@ -183,7 +243,7 @@ Prerequisites:
 + A Linux platform
 + GNU `make`, `tar` and `curl`
 + [Docker](https://www.docker.com/) or [Podman](https://podman.io/)
-+ [Node.js](https://nodejs.org/) v12+
++ [Node.js](https://nodejs.org/) v16+
 
 To build:
 

docs/example/index.html

@@ -63,7 +63,7 @@ <h5>Result</h5>
   </div>
 </div>
 
-<script src="https://cdn.jsdelivr.net/npm/@undecaf/zbar-wasm@0.9.16/dist/index.js"></script>
+<script src="https://cdn.jsdelivr.net/npm/@undecaf/zbar-wasm@0.10.0/dist/index.js"></script>
 <script src="js/main.js"></script>
 
 </body>

jest.config.cjs

@@ -4,8 +4,9 @@ module.exports = {
         'node_modules', 'dist'
     ],
     transform: {
-        '\\.wasm$': './test/jestFileTransformer.cjs',
+        '\\.wasm$': './tests/jestFileTransformer.cjs',
     },
     testEnvironment: 'node',
-    testTimeout: 15000,
-}
+    testTimeout: 5000,
+    testSequencer: './tests/testSequencer.cjs',
+}