parcel-plugin-externals - npm Package Compare versions

Comparing version 0.2.0 to 0.3.0-pre.20191112.1

CHANGELOG.md

 # parcel-plugin-externals Changelog
 
+## 0.3.0
+
+- Implemented a way to dynamically choose what (and how) to externalize (#4)
+- Fixed exception on browser property set to false (#6)
+
 ## 0.2.0
@@ -4,0 +9,0 @@

package.json

 {
   "name": "parcel-plugin-externals",
-  "version": "0.2.0",
+  "version": "0.3.0-pre.20191112.1",
   "description": "A plugin for Parcel to omit declared externals from being included in the emitted bundles.",
@@ -5,0 +5,0 @@ "main": "index.js",

README.md

@@ -78,2 +78,34 @@ # parcel-plugin-externals
 
+### Dynamic Dependency Resolution
+
+Sometimes you want to externalize a whole set of dependencies, potentially by a given rule, e.g., `react-*` or similar. For such cases you can also refer to a module that does the replacement rule determination:
+
+```json
+{
+  "externals": "./tools/ruleFactory.js"
+}
+```
+
+The rule factory module is just a simple Node.js module that exports a function:
+
+```js
+const rx = /node_modules\/react-(.*?)\//;
+
+module.exports = function(path) {
+  const result = rx.exec(path);
+
+  if (result) {
+    const suffix = result[1];
+    const name = suffix[0].toUpperCase() + suffix.substr(1);
+    return `react-${suffix} => React${name}`;
+  }
+
+  return undefined;
+};
+```
+
+What you need to return is either `undefined` (i.e., the module will not be externalized) or the replacement rule.
+
+**Remark**: If the rule does not contain the forward `=>` slash it will be interpreted as `returnValue => require('returnValue')`, where `returnValue` is the part returned from the function.
+
 ## Changelog
@@ -80,0 +112,0 @@

utils.js

@@ -17,7 +17,9 @@ const { readFileSync, existsSync } = require("fs");
       if (typeof moduleDefinition.browser === "string") {
-        return {
-          name,
-          rule,
-          path: resolve(moduleRoot, moduleDefinition.browser)
-        };
+        return [
+          {
+            name,
+            rule,
+            path: resolve(moduleRoot, moduleDefinition.browser)
+          }
+        ];
       }
@@ -28,6 +30,9 @@
           const desired = moduleDefinition.browser[repl];
-          replacements[resolve(moduleRoot, repl)] = resolve(
-            moduleRoot,
-            desired
-          );
+
+          if (desired) {
+            replacements[resolve(moduleRoot, repl)] = resolve(
+              moduleRoot,
+              desired
+            );
+          }
         });
@@ -38,7 +43,9 @@ }
         const modulePath = resolve(moduleRoot, moduleDefinition.module);
-        return {
-          name,
-          rule,
-          path: replacements[modulePath] || modulePath
-        };
+        return [
+          {
+            name,
+            rule,
+            path: replacements[modulePath] || modulePath
+          }
+        ];
       }
@@ -50,10 +57,18 @@ }
     });
-    return {
-      name,
-      rule,
-      path: replacements[directPath] || directPath
-    };
+
+    return [
+      ...Object.keys(replacements).map(r => ({
+        name,
+        rule,
+        path: replacements[r]
+      })),
+      {
+        name,
+        rule,
+        path: directPath
+      }
+    ];
   } catch (ex) {
     console.warn(`Could not find module ${name}.`);
-    return undefined;
+    return [];
   }
@@ -66,8 +81,23 @@ }
 
-function provideSupportForExternals(proto, externalNames, targetDir) {
-  const externals = externalNames
-    .map(name => resolveModule(name, targetDir))
-    .filter(m => !!m);
-  const ra = proto.getLoadedAsset;
-  proto.getLoadedAsset = function(path) {
+function wrapFactory(ruleFactory) {
+  return path => {
+    const rule = ruleFactory(path);
+
+    if (rule !== undefined) {
+      return `/${rule}.${extension}`;
+    }
+
+    return path;
+  };
+}
+
+function makeResolver(targetDir, externalNames) {
+  const externals = [];
+
+  for (const name of externalNames) {
+    const modules = resolveModule(name, targetDir);
+    externals.push(...modules);
+  }
+
+  return path => {
     const [external] = externals.filter(m => m.path === path);
@@ -79,6 +109,14 @@
 
-    return ra.call(this, path);
+    return path;
   };
 }
 
+function provideSupportForExternals(proto, resolver) {
+  const ra = proto.getLoadedAsset;
+  proto.getLoadedAsset = function(path) {
+    const result = resolver(path);
+    return ra.call(this, result);
+  };
+}
+
 function retrieveExternals(rootDir) {
@@ -95,8 +133,28 @@ const path = resolvePackage(rootDir);
       if (Array.isArray(externals)) {
-        return externals.concat(plain);
+        const values = externals.concat(plain);
+        return makeResolver(rootDir, values);
       } else if (typeof externals === "object") {
-        return Object.keys(externals)
-          .filter(name => typeof externals[name] === 'string')
+        const values = Object.keys(externals)
+          .filter(name => typeof externals[name] === "string")
           .map(name => `${name} => ${externals[name]}`)
           .concat(plain);
+        return makeResolver(rootDir, values);
+      } else if (typeof externals === "string") {
+        const externalPath = resolve(rootDir, externals);
+
+        if (!existsSync(externalPath)) {
+          console.warn(
+            `Could not find "${externals}". Looked in "${externalPath}".`
+          );
+        } else {
+          const resolver = require(externalPath);
+
+          if (typeof resolver === "function") {
+            return wrapFactory(resolver);
+          }
+
+          console.warn(
+            `Did not find a function. Expected to find something like "module.exports = function() {}".`
+          );
+        }
       }
@@ -103,0 +161,0 @@

New alerts

Dynamic require

Supply chain risk

Dynamic require can indicate the package is performing dangerous or unsafe dynamic code execution.

Found 1 instance in 1 package

Improved metrics

Total package byte prevSize

12953

increased by22.93%

Lines of code

226

increased by26.26%

Number of lines in readme file

119

increased by36.78%

Worsened metrics

Number of low supply chain risk alerts

5

increased by25%

No dependency changes