Node.js: Add code to handle separate shim modules.

Planend are the modules paper-jsdom and paper-jsdom-canvas, as shim modules that require and handle the dependencies as peer dependencies. Relates to #1252
paperjs · Mar 20, 2017 · 29de03d · 29de03d
1 parent 48e9ef6
commit 29de03d
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Showing 4 changed files with 72 additions and 41 deletions.
diff --git a/src/export.js b/src/export.js
@@ -35,8 +35,9 @@ paper = new (PaperScope.inject(Base.exports, {
 // If we're on node, require some additional functionality now before finishing:
 // - PaperScript support in require() with sourceMaps
 // - exportFrames / exportImage on CanvasView
-if (paper.agent.node)
+if (paper.agent.node) {
     require('./node/extend.js')(paper);
+}
 
 // https://github.com/umdjs/umd
 if (typeof define === 'function' && define.amd) {

diff --git a/src/node/canvas.js b/src/node/canvas.js
@@ -15,7 +15,7 @@
 // - Various Node Canvas methods, routed through from HTMLCanvasElement:
 //   toBuffer, pngStream, createPNGStream, jpgStream, createJPGStream
 
-module.exports = function(self) {
+module.exports = function(self, requireName) {
     var Canvas;
     try {
         Canvas = require('canvas');
@@ -26,13 +26,16 @@ module.exports = function(self) {
         // - On Node.js, it basically means the canvas is missing or not working
         //   which can be treated the same way.
         delete self.window;
-        console.info(
-                'Canvas module not found, running in a headless context.');
+        // Check the required module's name to see if it contains canvas, and
+        // only complain about its lack if the module requires it.
+        if (/\bcanvas\b/.test(requireName)) {
+            throw new Error('Unable to load canvas module.');
+        }
         return;
     }
 
-    var idlUtils = require('jsdom/lib/jsdom/living/generated/utils'),
-        HTMLCanvasElement = self.HTMLCanvasElement;
+    var HTMLCanvasElement = self.HTMLCanvasElement,
+        idlUtils = require('jsdom/lib/jsdom/living/generated/utils');
 
     // Add fake HTMLCanvasElement#type property:
     Object.defineProperty(HTMLCanvasElement.prototype, 'type', {

diff --git a/src/node/self.js b/src/node/self.js
@@ -13,11 +13,28 @@
 // Node.js emulation layer of browser environment, based on jsdom with node-
 // canvas integration.
 
-var self;
+var path = require('path');
+// Determine the name by which name the module was required (either 'paper',
+// 'paper-jsdom' or 'paper-jsdom-canvas'), and use this to determine if error
+// exceptions should be thrown or if loading should fail silently.
+var parent = module.parent.parent,
+    requireName = parent && path.basename(path.dirname(parent.filename));
+requireName = /^paper/.test(requireName) ? requireName : 'paper';
+
+var jsdom,
+    self;
 
 try {
-    var jsdom = require('jsdom');
+    jsdom = require('jsdom');
+} catch(e) {
+    // Check the required module's name to see if it contains jsdom, and only
+    // complain about its lack if the module requires it.
+    if (/\bjsdom\b/.test(requireName)) {
+        throw new Error('Unable to load jsdom module.');
+    }
+}
 
+if (jsdom) {
     // Create our document and window objects through jsdom.
     /* global document:true, window:true */
     var document = jsdom.jsdom('<html><body></body></html>', {
@@ -29,39 +46,9 @@ try {
         }
     });
     self = document.defaultView;
-
-    require('./canvas.js')(self);
-
-    // Define XMLSerializer shim, to emulate browser behavior.
-    // Effort to bring XMLSerializer to jsdom:
-    // https://github.com/tmpvar/jsdom/issues/1368
-    /*jshint -W082 */
-    function XMLSerializer() {
-    }
-
-    XMLSerializer.prototype.serializeToString = function(node) {
-        if (!node)
-            return '';
-        // Fix a jsdom issue where all SVG tagNames are lowercased:
-        // https://github.com/tmpvar/jsdom/issues/620
-        var text = node.outerHTML,
-            tagNames = ['linearGradient', 'radialGradient', 'clipPath',
-                'textPath'];
-        for (var i = 0, l = tagNames.length; i < l; i++) {
-            var tagName = tagNames[i];
-            text = text.replace(
-                new RegExp('(<|</)' + tagName.toLowerCase() + '\\b', 'g'),
-                function(match, start) {
-                    return start + tagName;
-                });
-        }
-        return text;
-    };
-
-    self.XMLSerializer = XMLSerializer;
-} catch(e) {
-    console.info(
-            'JSDom module not found, running in a headless context without DOM.');
+    require('./canvas.js')(self, requireName);
+    require('./xml.js')(self);
+} else {
     self = {
         navigator: {
             userAgent: 'Node.js (' + process.platform + '; U; rv:' +

diff --git a/src/node/xml.js b/src/node/xml.js
@@ -0,0 +1,40 @@
+/*
+ * Paper.js - The Swiss Army Knife of Vector Graphics Scripting.
+ * http://paperjs.org/
+ *
+ * Copyright (c) 2011 - 2016, Juerg Lehni & Jonathan Puckey
+ * http://scratchdisk.com/ & http://jonathanpuckey.com/
+ *
+ * Distributed under the MIT license. See LICENSE file for details.
+ *
+ * All rights reserved.
+ */
+
+module.exports = function(self) {
+    // Define XMLSerializer shim, to emulate browser behavior.
+    // Effort to bring XMLSerializer to jsdom:
+    // https://github.com/tmpvar/jsdom/issues/1368
+    self.XMLSerializer = function XMLSerializer() {
+    };
+
+    self.XMLSerializer.prototype = {
+        serializeToString: function(node) {
+            if (!node)
+                return '';
+            // Fix a jsdom issue where all SVG tagNames are lowercased:
+            // https://github.com/tmpvar/jsdom/issues/620
+            var text = node.outerHTML,
+                tagNames = ['linearGradient', 'radialGradient', 'clipPath',
+                    'textPath'];
+            for (var i = 0, l = tagNames.length; i < l; i++) {
+                var tagName = tagNames[i];
+                text = text.replace(
+                    new RegExp('(<|</)' + tagName.toLowerCase() + '\\b', 'g'),
+                    function(match, start) {
+                        return start + tagName;
+                    });
+            }
+            return text;
+        }
+    };
+};