Refactor serveFile into separate functions for different use cases

server/actions/serveFile.js

@@ -20,32 +20,7 @@ const AutoIndex = !process.env.DISABLE_INDEX;
  */
 const MaximumDepth = 128;
 
-function rewriteBareModuleIdentifiers(file, packageConfig, callback) {
+function serveMetadata(req, res) {
-  const dependencies = Object.assign(
-    {},
-    packageConfig.peerDependencies,
-    packageConfig.dependencies
-  );
-
-  const options = {
-    // Ignore .babelrc and package.json babel config
-    // because we haven't installed dependencies so
-    // we can't load plugins; see #84
-    babelrc: false,
-    plugins: [unpkgRewrite(dependencies)]
-  };
-
-  babel.transformFile(file, options, (error, result) => {
-    callback(error, result && result.code);
-  });
-}
-
-/**
- * Send the file, JSON metadata, or HTML directory listing.
- */
-function serveFile(req, res) {
-  if (req.query.meta != null) {
-    // Serve JSON metadata.
   getMetadata(
     req.packageDir,
     req.filename,
@@ -72,16 +47,31 @@ function serveFile(req, res) {
       }
     }
   );
-  } else if (req.stats.isFile()) {
+}
-    // Serve a file.
+
+function rewriteBareModuleIdentifiers(file, packageConfig, callback) {
+  const dependencies = Object.assign(
+    {},
+    packageConfig.peerDependencies,
+    packageConfig.dependencies
+  );
+
+  const options = {
+    // Ignore .babelrc and package.json babel config
+    // because we haven't installed dependencies so
+    // we can't load plugins; see #84
+    babelrc: false,
+    plugins: [unpkgRewrite(dependencies)]
+  };
+
+  babel.transformFile(file, options, (error, result) => {
+    callback(error, result && result.code);
+  });
+}
+
+function serveJavaScriptModule(req, res) {
   const file = path.join(req.packageDir, req.filename);
 
-    let contentType = getFileContentType(file);
-
-    if (contentType === "application/javascript" && req.query.module != null) {
-      contentType += "; charset=utf-8";
-
-      // Serve a JavaScript module.
   rewriteBareModuleIdentifiers(file, req.packageConfig, (error, code) => {
     if (error) {
       console.error(error);
@@ -105,7 +95,7 @@ function serveFile(req, res) {
       // Cache modules for 1 year.
       res
         .set({
-              "Content-Type": contentType,
+          "Content-Type": "application/javascript; charset=utf-8",
           "Content-Length": Buffer.byteLength(code),
           "Cache-Control": "public, max-age=31536000",
           "Cache-Tag": "file,js-file,js-module"
@@ -113,15 +103,20 @@ function serveFile(req, res) {
         .send(code);
     }
   });
-    } else {
+}
-      // Serve some other static file.
+
+function serveStaticFile(req, res) {
+  const file = path.join(req.packageDir, req.filename);
   const tags = ["file"];
 
   const ext = path.extname(req.filename).substr(1);
+
   if (ext) {
     tags.push(`${ext}-file`);
   }
 
+  let contentType = getFileContentType(file);
+
   if (contentType === "application/javascript") {
     contentType += "; charset=utf-8";
   }
@@ -146,9 +141,11 @@ function serveFile(req, res) {
 
   stream.pipe(res);
 }
-  } else if (AutoIndex && req.stats.isDirectory()) {
+
-    // Serve an HTML directory listing.
+function serveIndex(req, res) {
-    getEntries(path.join(req.packageDir, req.filename)).then(
+  const dir = path.join(req.packageDir, req.filename);
+
+  getEntries(dir).then(
     entries => {
       const html = renderPage(IndexPage, {
         packageInfo: req.packageInfo,
@@ -174,6 +171,24 @@ function serveFile(req, res) {
         .send(`Cannot read entries for ${req.packageSpec}${req.filename}`);
     }
   );
+}
+
+/**
+ * Send the file, JSON metadata, or HTML directory listing.
+ */
+function serveFile(req, res) {
+  if (req.query.meta != null) {
+    serveMetadata(req, res);
+  } else if (req.stats.isFile()) {
+    const contentType = getFileContentType(req.filename);
+
+    if (contentType === "application/javascript" && req.query.module != null) {
+      serveJavaScriptModule(req, res);
+    } else {
+      serveStaticFile(req, res);
+    }
+  } else if (req.stats.isDirectory() && AutoIndex) {
+    serveIndex(req, res);
   } else {
     res
       .status(403)